G8 Performance gears *POLL ADDED* VOTE...

[GM_Fan]

I contacted Richmond Gear today and asked if they would consider producing a performance ratio for us G8 owners. They said they weren't aware there was a demand. I asked them to stop by the forum and look around. If you want performance gears for your car post up and don't forget to contact them as well.

Face Book:

http://www.facebook.com/pages/Richmond-Gear/181251909330

EMail:
engineering@richmondgear.com


Phone: 864-843-9231

.

[r33pwrd]

I would be interested as long as there way a $$ savings over the full diff. (assuming I can find someone local to install)

I would send them a link to this thread to follow!

[SRG963]

I would be interested depending on cost....3.27 or 3.45 for me.


Edit: Just Voted for 3.27's

[GM_Fan]

I was thinking if we could get the gears without having to buy the whole Diff assembly it would be great in 3.45, 3.73, or 3.90 ratio.

[GM_Fan]

I would send them a link to this thread to follow!

:) I will do that.

[Voice of Reason]

I'd buy 3.27s from them today if my total out of pocket saved a good amount over a differential swap. Unfortunately they probably won't start with 3.27s if they do make gears for us so I'm probably going to have to go the more expensive route if I want to do the swap this spring.

[GeorgeInNePa]

The Camaro gears are in the $700 range, just to give you an idea.

Then it's plus parts and labor...

[2QUIK4U]

I would buy a set of gears if they were available. I have done a few gear swaps in the past. Not the most enjoyable process but even at $700 thats less than half the cost of a new diff. I would like the 3.45 ratio but I would take a 3.27 or even 3.70

[wnt2gofst]

HTC-ST7377/1.59.502.3 (67150) Opera/9.50 (Windows NT 5.1; U; en) UP.Link/6.3.1.17.0

[wnt2gofst]

I would buy gears as well. I know crazypaul said he can get gears from downunder for around 700 if remeber right. but you have frieght shipping on top that.
HTC-ST7377/1.59.502.3 (67150) Opera/9.50 (Windows NT 5.1; U; en) UP.Link/6.3.1.17.0

[r33pwrd]

The Camaro gears are in the $700 range, just to give you an idea.

Then it's plus parts and labor...

at that point I would just buy the diff and have a backup.... I cant image install being any less than 300 bucks for the gears?

[Voice of Reason]

With 3.27 gears you'll see 60mph at the top of second gear. With 3.45s it's closer to 55 at the top of second. I never checked 3.70s but it's got to be closer to 50mph. IMO that's too much shifting before 60mph for daily driving. And with our 1st gear ratio being 4.03 I think 3.45 or 3.70 final drive ratio will just result in tons of tire smoke on the street. On the strip it's different because sticky tires and track prep change the equation.

[Voice of Reason]

at that point I would just buy the diff and have a backup.... I cant image install being any less than 300 bucks for the gears?

I bet it's closer to $500. I think I saw somewhere that the bolts alone, which cannot be reused, are like $15-20 each, and theres like 8 of them.

The only way it would be worth while to me is if the gears were < $500. Otherwise like you said you may as well get a complete differential. That way if I ever sell the car I can put the stocker back in and recoup some of the cost. I'm sure I could easily sell a 30k mile 3.27 differential here for $800. I know I'd pay that right now.

[Devilish34]

Gears and a Diff the stock LSD has to go

[GeorgeInNePa]

With 3.27 gears you'll see 60mph at the top of second gear. With 3.45s it's closer to 55 at the top of second. I never checked 3.70s but it's got to be closer to 50mph. IMO that's too much shifting before 60mph for daily driving. And with our 1st gear ratio being 4.03 I think 3.45 or 3.70 final drive ratio will just result in tons of tire smoke on the street. On the strip it's different because sticky tires and track prep change the equation.

Rule of thumb for 3.70s is approx 500rpm higher that what you are running now.

If 80mph is 2000rpm in 6th, it will be 2500 with the 3.70s.

I was against the idea of 3.70s before, but now I think they are the way to go with this heavy pig, even with the gearing of the A6.

[Voice of Reason]

Now I'm second guessing 3.27 vs 3.45. I found this website and when I use 6200 as the redline 3.45s have 60mph at the top of second. Now if we stick with a 6000 redline 2nd gear ends 2mph earlier in each sceneario.

Here's the website: http://www.f-body.org/gears/


Rear / Speed at 6200
2.92: 42 71 110 147 198 252
3.27: 37 64 98 131 177 225
3.45: 35 60 93 124 168 213
3.70: 33 56 87 116 156 199

The reason I'm doing type of analysis and not how many rpms the engine is turning at highway speeds in 6th gear is because our 6th gear ratio of 0.67 makes any gear swap attractive. It's 1st and 2nd gears and how much traction and speed I can get out of them that I'm most concerned with.

[G8GT721]

^what figures do you type in the the 1st thru 6th catagories

[Voice of Reason]

4.03
2.36
1.53
1.15
0.85
0.67

[G8GT721]

would you want to pick your gears so your finish/trap at or near redline(6200)? For example if i trap at 120mph, should i choose 3.45's so i would finish at 6100rpm @120 in 4thgear

[2xd]

Richmond is looking for input on what new gears are needed. The have a facebook page:

http://www.facebook.com/pages/Richmond-Gear/181251909330

If you are on facebook check it out and make your requests there.

[travis gore]

I posted on facebook

[Ktlplxm]

I wouldn't go any higher than a 3.27 gear. Have you ever seen the fuel mileage in a M6 G8? Its atrocious, and they have a smaller 6th than we do.

[616 of 933]

I would want a set but I want to do other mods first. Gear would more then likely be the last thing I did. I still need alot of other things

[Ktlplxm]

Since this is a thread pretty much started to show interest to Richmond Gears the desire and demand for gear sets, it would be best for those that don't want them not to post. They will want as many positive responses as necessary. After all, they want to know who wants them and which gears they want, not who doesn't want them.

[Devilish34]

Can we add a poll to help as a post count??? Maybe list gear ratios wanted

[travis gore]

I have a response from richmond on facebook

Travis, what year model? If there is enough interest we would make them. I assume you are looking for a street gear.

[Ktlplxm]

I have a response from richmond on facebook

Travis, what year model? If there is enough interest we would make them. I assume you are looking for a street gear.

People will want the street series, NOT the race series. Race series are very loud even in race cars. You trade off comfort for strength.

[Ktlplxm]

If they need one relatively close I could even leave them my car for a week or two, but as I said before, I'm only interested in 3.27's

[SpeedRacerX]

Some data for those who like it and are considering this...

70 mph, 6th gear automatic, 2.92 stock = approx 1750-1800 rpm.
3.27 = 1960 rpm.
3.45 = 2068-2124 rpm.
3.70 = 2217-2281 rpm.
3.90 = 2337-2404 rpm.
4.10 = 2457-2527 rpm.

My test, 70 mph, 6th gear, rpms are 1750.
Drop into 5th gear at 70 mph, rpms are 2250/2300 which is about the same as a 3.70 gear. Seemed great to me and still easy on the motor. Dropping to 4th gear and cruise at 70 mph, rpms are 3025. This is too much; not ridiculous or crazy but not for a nice 4-door like this.

Gas mileage test:

6th gear, 1750 rpms, 3 reading average from DIC after fresh reset = 24.4 mpg ave (with my mods of course).
5th gear, 2300 rpms, 3 reading average from DIC after fresh reset = 21.5 mpg ave.

90% of my mileage is around town, local, and start stop so the highway loss does NOT bother me. I would bet my car will get better overall average gas mileage with the new gear just because it will take much less throttle input to move this thing 100 times a day.

3.70 gear for me!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Yes George, I've been saying it for 9 months. This big heavy pig needs the gear.

If I did a ton of highway driving, I probably wouldn't do more than a 3.27. Maybe the 3.45 is a good middle of the road ratio, which is about what's in most manual Vettes. Auto Vettes run smaller number ratios but then again they are 700-800 pounds lighter.

[SpeedRacerX]

So how do I say I'm interested? I do not use facebook.

[Voice of Reason]

SpeedRacer, I agree that 3.70s would be good for highway driving. But how will you be able to use 1st gear on the street? With our 4.03 first gear a 3.70 rear end would mean a 14.92 multiplication factor. For comparison, a 2010 Mustang GT 5 speed has a 3.34 first gear ratio. So to get the same multiplication factor it would take a 4.46 rear end in that car. You only ever hear people talking about that much gear on Mustang forums if it's a track car.

If I keep with the Mustang comparison, 3.27 gears for us is like 3.95 gears for them. And 3.45 for us is 4.16 for them.

I wish I could attach a spreadsheet here where I worked out some comparisons between my reference vehicle, my old 03 Cobra that made 450rwhp, and my G8. I took weight, rwhp, final drive ratio, and transmission ratio all into account to determine how the vehicles acceleration would compare with different rear end ratios. It's not an exact science, but it gives me a ballpark.

[edmanet]

I wouldn't go any higher than a 3.27 gear. Have you ever seen the fuel mileage in a M6 G8? Its atrocious, and they have a smaller 6th than we do.

I got 24mpg driving at roughly 70mph on the 500 mile trip from LIVERNOIS to my house with the 3.27 diff.

[jakesg8]

I've gotten 22mpg with 3.70's and a A6. But I've got a 6.2. The ? about 1st gear on the street. The 275-35-19 BFG Kdw2 help. But even before the gear with my convertor any stall would blow the tires off. 20 mph roll isnt a problem with the new tires. I wouldn't go back to 2.92 of 3.27. like speedracer said Heavy cars need gear!!!! I would have 4.10's if I could get them. I havent ran it in the 1/4 mile yet just the 1/8. That is going to change tomorrow!!

[Ktlplxm]

I got 24mpg driving at roughly 70mph on the 500 mile trip from LIVERNOIS to my house with the 3.27 diff.

3.27 is the way to go for me

[Devilish34]

3.27 is the way to go for me

If your car made any power you wouldn't need gears

[SpeedRacerX]

SpeedRacer, I agree that 3.70s would be good for highway driving. But how will you be able to use 1st gear on the street? With our 4.03 first gear a 3.70 rear end would mean a 14.92 multiplication factor. For comparison, a 2010 Mustang GT 5 speed has a 3.34 first gear ratio. So to get the same multiplication factor it would take a 4.46 rear end in that car. You only ever hear people talking about that much gear on Mustang forums if it's a track car.

If I keep with the Mustang comparison, 3.27 gears for us is like 3.95 gears for them. And 3.45 for us is 4.16 for them.

I wish I could attach a spreadsheet here where I worked out some comparisons between my reference vehicle, my old 03 Cobra that made 450rwhp, and my G8. I took weight, rwhp, final drive ratio, and transmission ratio all into account to determine how the vehicles acceleration would compare with different rear end ratios. It's not an exact science, but it gives me a ballpark.

So, can you share with us how a G8 would accelerate with 2.92, 3.27, 3.45, 3.70, 3.90, and 4.10??? I've been trying to figure this out for months.

To the point you made about first gear multiplication, how does your gear ratio acceleration spreadsheet account for traction or lack thereof?

[SpeedRacerX]

I've gotten 22mpg with 3.70's and a A6. But I've got a 6.2. The ? about 1st gear on the street. The 275-35-19 BFG Kdw2 help. But even before the gear with my convertor any stall would blow the tires off. 20 mph roll isnt a problem with the new tires. I wouldn't go back to 2.92 of 3.27. like speedracer said Heavy cars need gear!!!! I would have 4.10's if I could get them. I havent ran it in the 1/4 mile yet just the 1/8. That is going to change tomorrow!!

And I'm not building a track car, per se - other than maybe a visit or two per year. I can't afford a maggie or twin turbo and I won't be cracking the car open anytime soon for a CAM or Converter.

What I want is a daily-driven, mannerly, street sleeper that will surprise the crap out of unsuspecting Mustangs, BMWs, Lexus', Camaros, Challengers, Chargers, and maybe even some stock Vettes. Unless I was putting on a show, I wouldn't mash the gas with a 3.70 rear at a light anyway. I can't even do that today without wasting tires. That would be senseless. I'd rollout at 1/2 to 3/4 throttle, with wider rear tires I'm planning, and then bury it. The 3.70s should have me chirping and clicking through gears pretty quickly while keeping my power in the high end of the band...

Please convince me this isn't the way to go because I'm open to all suggestions.

[jakesg8]

I know how mine run's. She went 7.65 in the 1/8 with out taking out the seat and with me in it I'm 6'1 270.And that was before I tuned it. I do have long tubes OTR cai and a stall convertor. In my opinion thats pretty go for a DD.Hell it will out run my old 70 442 W30 and the W31. And those are the pinnacle of Muscle cars.And both of them have 3.91's in them and are lighter.

[Devilish34]

I know how mine run's. She went 7.65 in the 1/8 with out taking out the seat and with me in it I'm 6'1 270.And that was before I tuned it. I do have long tubes OTR cai and a stall convertor. In my opinion thats pretty go for a DD.Hell it will out run my old 70 442 W30 and the W31. And those are the pinnacle of Muscle cars.And both of them have 3.91's in them and are lighter.

7.65 was my 1/8 on a 11.87 run

[jakesg8]

7.65 was my 1/8 on a 11.87 run

But arent u and george pulling weight out.but it was 91 deg here with high humidity

[Devilish34]

[QUOTE=jakesg8;192107]But arent u and george pulling weight out.but it was 91 deg here with high humidity[/QUOTE

No I run stock weight and launch at 1000-1200 rpms. Last couple of times I had a 1/2 tank or better

[jakesg8]

[QUOTE=jakesg8;192107]But arent u and george pulling weight out.but it was 91 deg here with high humidity[/QUOTE

No I run stock weight and launch at 1000-1200 rpms. Last couple of times I had a 1/2 tank or better

I was coming out at 2000 2500 I had about the same amount of fuel.

[SpeedRacerX]

I know how mine run's. She went 7.65 in the 1/8 with out taking out the seat and with me in it I'm 6'1 270.And that was before I tuned it. I do have long tubes OTR cai and a stall convertor. In my opinion thats pretty go for a DD.Hell it will out run my old 70 442 W30 and the W31. And those are the pinnacle of Muscle cars.And both of them have 3.91's in them and are lighter.

Holy crap that is good! Considering my 1/8th with my mods was 8.6 (I would probably dyno same as a stock auto GXP). You are running almost 1 second less in the 1/8th!!!

If you remove the typical gain from the stall and LT headers, I'd say the gears alone make for a .5 to .6 second improvement in 1/8th time, let alone how it might help in the quarter. NICE!!!!!!!!!!!

[SpeedRacerX]

FWIW, while we all debate, there is not one person on either Forum running 3.45s, 3.70s, or 3.90s who has said they regret it.

[jakesg8]

FWIW, while we all debate, there is not one person on either Forum running 3.45s, 3.70s, or 3.90s who has said they regret it.

:woohoo:



Wait till the Camaro guys get those 4.10's Game over, cancel Christmas for us LOL

[Ktlplxm]

If your car made any power you wouldn't need gears

So with that line of thinking you need a what, 4.56, 5.14? :nah:

So, can you share with us how a G8 would accelerate with 2.92, 3.27, 3.45, 3.70, 3.90, and 4.10??? I've been trying to figure this out for months.

To the point you made about first gear multiplication, how does your gear ratio acceleration spreadsheet account for traction or lack thereof?

There's no way that it can. Wheelspin/traction are uncontrollable factors. Running a 3.42 gear in one car is identical to running it in another car, you just have to compare apples to apples. You never say running a 3.42 gear in 4L60E is like running a 3.93 in a T56. You might as well say they're identical except one is running a 25" tire and a 27" tire. It makes about as much sense as guys telling you a 4.10 isn't really a 4.10 gear unless its with X" height tire. It is what it is. Overall gear multiplication plays less of a factor in acceleration than traction does. If someone doubts that, look at grudge cars and the myriad vehicles with Powerglides.



FWIW, while we all debate, there is not one person on either Forum running 3.45s, 3.70s, or 3.90s who has said they regret it.

Maybe thats because the people that have already installed those care more about track times than they do driving. Its like the ones who run straight pipes and then say thats there is no drone and it isn't that loud. It's all relative to the end user.

[Voice of Reason]

Here's the chart I put together. I know this is not an exact science, and people much smarter than me are going to point out it's faults and I welcome it so that I can better understand what gear to pick for myself.
http://forum.grrrr8.net/picture.php?albumid=160&pictureid=853
So how do you read this thing?
Rows 1-9 show vehicle configurations along with transmission ratios and final drive ratio. I have my reference car, 4 configurations of the GT, a GXP, a 10 Mustang, and a GT500.
Line 11 is rwhp for each vehicle. Note that the GT is not stock here.
Lines 12-17 are trans ratio*final drive ratio*hp
Line 19 is vehicle weight with driver
Lines 20-25 are hp calculation above divided by weight. I'm trying to get all vehicles on a level playing field here by taking weight into consideration.
Lines 27-33 are my "end result". The Cobra is the reference vehicle so it accelerates at 100% through all it's gears. The rest of the percentages show me in relation to my Cobra how each car accelerates through it's gears. For example, the GT w 2.92s accelerates at 92.5% of the Cobra rate through first gear. Second pulls at 80.9% strength, third at 71.8%, etc. With 3.27s it will gave better pull in 1st gear at 103.6%. 3.70s will have much better pull at 109.3%.

Caveat: The following are not taken into consideration!
- Torque curve. The Cobra has a torque curve as flat as a table and it sits at 480rwtq where ours is no where near that. I am only using peak rwhp in my calculations.
- Traction
- What each vehicles maximum speed is at redline in each gear


Now I know that my Cobra had major traction issues in 1st gear with street tires, and still struggled with traction (on the street!) when I drove it with drag radials. So when I see those percentages for first gear get above 100% I get concerned.

[GeorgeInNePa]

FWIW, while we all debate, there is not one person on either Forum running 3.45s, 3.70s, or 3.90s who has said they regret it.

All and I mean ALL the Camaro guys(yes even the A6s) are salivating at the thought of 3.70, 3.90, and 4.10 gears for the 5th gen.

That car is with-in 150lbs of our car.

[familycaronROIDS!]

I am interested in 3.45 gears.....

[dv327]

I would like 3.45s!!!!!!!!!!

[G8GT721]

would you want to pick your gears so your finish/trap at or near redline(6200)? For example if i trap at 120mph, should i choose 3.45's so i would finish at 6100rpm @120 in 4thgear

does this make any sense?

[Devilish34]

So with that line of thinking you need a what, 4.56, 5.14? :nah:



That might help fix my back

[Ktlplxm]

only if you never plan on getting any faster. With a gear change , and traction, you should reach that speed faster, so if you choose to pick one that way, you should think ahead.

[Ktlplxm]

That might help fix my back

I can walk on it for ya. If 300+ lbs won't pop it your screwed lol

[Ktlplxm]

All and I mean ALL the Camaro guys(yes even the A6s) are salivating at the thought of 3.70, 3.90, and 4.10 gears for the 5th gen.

That car is with-in 150lbs of our car.

An overwhelming percentage of Al-Qaeda suicide bombers are willing to die to bang a bunch of redheaded virgins... doesn't make em right

[Devilish34]

I can walk on it for ya. If 300+ lbs won't pop it your screwed lol


no thanks fat ass...I'll stick with the red head and blond girls that I go to

[Ktlplxm]

no thanks fat ass...I'll stick with the red head and blond girls that I go to

always so mean. :windy:

[GeorgeInNePa]

An overwhelming percentage of Al-Qaeda suicide bombers are willing to die to bang a bunch of redheaded virgins... doesn't make em right

It's personal preference, just like converters.

;)

[GeorgeInNePa]

only if you never plan on getting any faster. With a gear change , and traction, you should reach that speed faster, so if you choose to pick one that way, you should think ahead.

For many, it's a viable option. $1K on a gear swap or $15K for a 427 on boost...

[Ktlplxm]

It's personal preference, just like converters.

;)

What they get to choose a preference of redhead blonde or brunette? Or do they choose between virgin and porn star?

Oh you're talking about the gears again, my bad

[GM_Fan]

I voted for 3.45 because that should be the minimun or it would be a waste of time to do less.

I'd vote for 3.70 if I had two choices.

[Ktlplxm]

For many, it's a viable option. $1K on a gear swap or $15K for a 427 on boost...

best part is I have no where near that in mine :)

but what I was trying to explain to him was if he wants to choose a gear to put him at redline going through the traps, he needs to take into account he will be accelerating quicker, and will be at a higher speed when he goes through the lights, so that should be taken into consideration.
Never questioned the viability of the gear swap. But you are correct in my method: more power on tap, less gear necessary, less gear equals lower rpm at cruise which gives greater driveability

[616 of 933]

How can i find out RPM's with the different gears at 60 MPH with the stock tire size

[Voice of Reason]

How can i find out RPM's with the different gears at 60 MPH with the stock tire size

Read my posts on page 2 of this thread. There's a link to a website that will give you some info

[Ktlplxm]

ong way to do it but effective


RPM= (mph x trans gear ratio x rear gear ratio x 336)/26.73

lets say you want to find out the rpm for 60 mph with a 3.42 in 6th:
RPM= (60 x .67 x 3.42 x 336)/26.73
RPM= (43436.74)/26.73
RPM= 1625.02

[616 of 933]

http://www.csgnetwork.com/rearendgearcalc.html


i found this one wise going to long way

[616 of 933]

after looking at some numbers I think for me is either 3.70 or 3.90

[-Ray-]

I wouldn't go any higher than a 3.27 gear. Have you ever seen the fuel mileage in a M6 G8? Its atrocious, and they have a smaller 6th than we do.

This.

[SpeedRacerX]

Just got back from a high school ice hockey game. As I watched the Zamboni crawl around I couldn't help but wonder what it's final drive ratio is? :)

I think it does 0-2 mph almost instantaneously.

[99-LS1-SS]

I wouldn't go any higher than a 3.27 gear. Have you ever seen the fuel mileage in a M6 G8? Its atrocious, and they have a smaller 6th than we do.

I drove to Texas (~1100 miles) and averaged 21.5 MPG and 72 MPH. The 3.70 M6 gear CLEARLY wasn't made for mileage. Sometimes I wish 3.45-3.50 gear in my car.

[deputycrawford]

If 99LS1SS got 21.5 on a trip then I am going with 3:70 gears. Come on guys, we got these cars for speed. Don't start counting milage now.

Jerry

[jakesg8]

I know if I wanted mileage. I would of bought a 4cyl Cobalt:hang:

[-Ray-]

If 99LS1SS got 21.5 on a trip then I am going with 3:70 gears. Come on guys, we got these cars for speed. Don't start counting milage now.

Jerry

I counted mileage since the day I bought my G8. My company payed me to drive my car. The better the mileage it got the more money in my pocket.
I already drive a Silverado that gets low mileage.
I didn't get it for speed. It may be fast, but that's not why I bought it.

[Devilish34]

I counted mileage since the day I bought my G8. My company payed me to drive my car. The better the mileage it got the more money in my pocket.
I already drive a Silverado that gets low mileage.
I didn't get it for speed. It may be fast, but that's not why I bought it.

When you retire can I have your job lol

[-Ray-]

When you retire can I have your job lol

You can have it after I get back from Phoenix next week.

[GeorgeInNePa]

I counted mileage since the day I bought my G8. My company payed me to drive my car. The better the mileage it got the more money in my pocket.
I already drive a Silverado that gets low mileage.
I didn't get it for speed. It may be fast, but that's not why I bought it.

Blasphemer! Heretic!

Burn the witch!!!




:spank:

[-Ray-]

Lol

[99-LS1-SS]

Blasphemer! Heretic!

Burn the witch!!!




:spank:



I know if I wanted mileage. I would of bought a 4cyl Cobalt:hang:

LOL! These^

[SpeedRacerX]

OP - did you post or think about posting this on the other Forum also? There are "gear-heads" over there too you know and it might help give Richmond a better sampling?

[99-LS1-SS]

I think he did and it was removed because someone complained.

[SRG963]

I think he did and it was removed because someone complained.

It's still there.....just the NSV link was edited out.
http://www.g8board.com/forums/showthread.php?t=27922

[GM_Fan]

If there were performance sets sitting on self in Aussie Land somewhere we'd be buying them. I made the same point on another board.

Since there are a couple hundred thousand cars over in the US, Australia, Europe, Saudi Arabia and counting I'm sure someone could produce a few thousand sets and sell them.

[Ktlplxm]

I drove to Texas (~1100 miles) and averaged 21.5 MPG and 72 MPH. The 3.70 M6 gear CLEARLY wasn't made for mileage. Sometimes I wish 3.45-3.50 gear in my car.

I would sell the car if I got that mileage lol
21.5 x 18.5 gallons = 397.75 miles to a tank
30 x 18.5 gallons = 555.00 miles
157.25 difference
Hmmm. @ 1 tank a week I save 5.25 gallons (give or take a .5) Over a year thats 273 gallons. $3 per gallon.... $819.00, 5 years worth of payments, $4095.00. If a GXP cost $6000 more (on the pontiac site) thats..$10,095.00...
Bet you could buy a big shortblock and a blower for that
Why is a GXP a good option again? hahaha

Sorry brandon, had to do it


I know if I wanted mileage. I would of bought a 4cyl Cobalt:hang:
I enjoy my mileage. 20 or so city, 30 highway at 75-80 mph.
If speed were my primary concern I would have bought a Vette.

[familycaronROIDS!]

3.45-3.70 for me. Just cant decide between the 2... most likely 3.70

[Devilish34]

I would sell the car if I got that mileage lol
21.5 x 18.5 gallons = 397.75 miles to a tank
30 x 18.5 gallons = 555.00 miles
157.25 difference
Hmmm. @ 1 tank a week I save 5.25 gallons (give or take a .5) Over a year thats 273 gallons. $3 per gallon.... $819.00, 5 years worth of payments, $4095.00. If a GXP cost $6000 more (on the pontiac site) thats..$10,095.00...
Bet you could buy a big shortblock and a blower for that
Why is a GXP a good option again? hahaha

Sorry brandon, had to do it



Always so mean

[99-LS1-SS]

M6!

[GeorgeInNePa]

I would sell the car if I got that mileage lol
21.5 x 18.5 gallons = 397.75 miles to a tank
30 x 18.5 gallons = 555.00 miles
157.25 difference
Hmmm. @ 1 tank a week I save 5.25 gallons (give or take a .5) Over a year thats 273 gallons. $3 per gallon.... $819.00, 5 years worth of payments, $4095.00. If a GXP cost $6000 more (on the pontiac site) thats..$10,095.00...
Bet you could buy a big shortblock and a blower for that
Why is a GXP a good option again? hahaha

Sorry brandon, had to do it


I enjoy my mileage. 20 or so city, 30 highway at 75-80 mph.
If speed were my primary concern I would have bought a Vette.

How many kids can I fit in the backseat of a Vette?

;)

[edmanet]

How many kids can I fit in the backseat of a Vette?

;)


Three if you pile them just right!!!

[Keith2]

I'm interested in a 3.45... However, the 3.70 sounds good too.. Trying to decide what would work best with my 3200 stall.

[99-LS1-SS]

3.70s will be steep with the gearing of the A6.

[Ktlplxm]

How many kids can I fit in the backseat of a Vette?

;)

Ewww...... kids
Thankfully have none of the little tax exemptions

[Devilish34]

Ewww...... kids
Thankfully have none of the little tax exemptions

Yes one of you is enough

[edmanet]

Ewww...... kids
Thankfully have none of the little tax exemptions

Hell they're not little.....One of mine is 25 and counting.

[Ktlplxm]

Yes one of you is enough

No argument here

[GeorgeInNePa]

Yes one of you is enough

Especially since he's big enough to be two...

:rofl:

[jakesg8]

3.70s will be steep with the gearing of the A6.

Brandon, Its not bad at all. I've had them in for 6 months now. I've driven my car to Knoxville from Florida 3 times with them.I have no regrets of putting them in.I wish you guys could drive my car. That would put all this discussion to rest.

[SS Enforcer]

You won't go any harder with 3.7's over the 3.45's at the track due to the fact the A6 is so lowly geared in the first place. I have driven both and there isn't much difference really. In a bolt on car just raise the rev limiter and trap around 6600 rpm in 3rd with the stock 2.92's.

cheers

[Ktlplxm]

Brandon, Its not bad at all. I've had them in for 6 months now. I've driven my car to Knoxville from Florida 3 times with them.I have no regrets of putting them in.I wish you guys could drive my car. That would put all this discussion to rest.

I doubt seriously that it would put the discussion to rest. It would just go to show that some people have different views on what is tolerable and what is driveable in a vehicle. If he already has 3.70's in his M6 car and thinks they are too steep for highway gears, then there is no way he would feel differently about them in a A6 car. Glad to hear you enjoy them though. I remember how much I disliked 3.73's in A4 F-bodies. They worked well at the track, but sucked on the highway at cruising speeds, and once a car car made any real power, they were completely unnecessary (you could go just as fast with 3.23's or 3.42's)

[GM_Fan]

The GTOs have 3.46 gears from the factory for the 6 speed and 4 speed auto.

The 6 speed automatic of the G8 with 3.45 gears would be a good match. IMO

[Voice of Reason]

The GTOs have 3.46 gears from the factory for the 6 speed and 4 speed auto.

The 6 speed automatic of the G8 with 3.45 gears would be a good match. IMO

The difference here is in transmission ratios. The GTO's 4 speed automatic transmission (as well as the LS1 fbody autos) has the following ratios:

1st 3.06
2nd 1.63
3rd 1
4th 0.7

That means a G8 with 3.45s would have a comporable ratio to a GTO with 4.54s for 1st and 2nd gears. They must have sourced our 4.03 1st and 2.36 2nd gear ratios from trucks designed to pull up tree stumps or something, because they make any comparisons with other cars just wacko.

And for another comparison, 6 speed manual GTOs have the following ratios:
2.97:1 2.07:1 1.43:1 1.00:1 0.84:1 0.57:1

[Ktlplxm]

The difference here is in transmission ratios. The GTO's 4 speed automatic transmission (as well as the LS1 fbody autos) has the following ratios:

1st 3.06
2nd 1.63
3rd 1
4th 0.7

That means a G8 with 3.45s would have a comporable ratio to a GTO with 4.54s for 1st and 2nd gears. They must have sourced our 4.03 1st and 2.36 2nd gear ratios from trucks designed to pull up tree stumps or something, because they make any comparisons with other cars just wacko.

And for another comparison, 6 speed manual GTOs have the following ratios:
2.97:1 2.07:1 1.43:1 1.00:1 0.84:1 0.57:1

I think what most of us are looking at are the final gear ratios, not the initials. Going solely by initial gears we have plenty with the 2.92. Our first gear is ridiculously steep. It was designed so that you could run a very modest tail gear and still have enough "get-up and go".

Numerically the 3.45 seems to be the most practical:
In a 6L80E it yields a 13.89 and 2.30 G.M for first and last gears respectively. In an GTO or Fbody thats like having a 4.54 gear through first gear and then having a 3.28 gear to cruise with. Whereas:
The 3.27 yields 4.30/3.11
The 3.70 yields 4.86/3.52
The 3.90 Yields 5.13/3.72
The 4.10 yields 5.39/3.90
Hopefully this breakdown will give some people a little perspective. No matter what, RICHMOND WE NEED GEARS

[edmanet]

I think what most of us are looking at are the final gear ratios, not the initials. Going solely by initial gears we have plenty with the 2.92. Our first gear is ridiculously steep. It was designed so that you could run a very modest tail gear and still have enough "get-up and go".

Numerically the 3.45 seems to be the most practical:
In a 6L80E it yields a 13.89 and 2.30 G.M for first and last gears respectively. In an GTO or Fbody thats like having a 4.54 gear through first gear and then having a 3.28 gear to cruise with. Whereas:
The 3.27 yields 4.30/3.11
The 3.70 yields 4.86/3.52
The 3.90 Yields 5.13/3.72
The 4.10 yields 5.39/3.90
Hopefully this breakdown will give some people a little perspective. No matter what, RICHMOND WE NEED GEARS

Good easy to understand info.

[GM_Fan]

Great data ktlplxm.

[GM_Fan]

So who has went the extra mile and made a contact attempt?

[Voice of Reason]

Well, I just bit the bullet and ordered a 3.27 differential. I've been on the fence between 3.27s and 3.45s for longer than this thread has been going and I just got my last bit of info tipping me in my final direction. My tune is with Livernois and I checked to see if they have tuned any 3.45s yet and as of today they have not. To me, because they have tuned for 3.27s and because the A6 GXP comes with them from the factory as a good tuning reference, I don't want to risk months of back and forth trying to get the car to drive properly under normal every day driving conditions.

I'm relieved actually. The allure of better performance with 3.45s is what has kept them in the running for so long. But the decision to go with 3.27s I'm confident will keep with what this car (for me) is all about. 99% daily driver with civil manners that is faster than 95% of the cars on the road around me.

[Ktlplxm]

So who has went the extra mile and made a contact attempt?

I'm only a few hours from richmond and have sent them an email, but haven't heard anything back. Lots of times emails get "spammed" because of the spelling of my account name (same as on here)

[GRRRR8]

I think what most of us are looking at are the final gear ratios, not the initials. Going solely by initial gears we have plenty with the 2.92. Our first gear is ridiculously steep. It was designed so that you could run a very modest tail gear and still have enough "get-up and go".

Numerically the 3.45 seems to be the most practical:
In a 6L80E it yields a 13.89 and 2.30 G.M for first and last gears respectively. In an GTO or Fbody thats like having a 4.54 gear through first gear and then having a 3.28 gear to cruise with. Whereas:
The 3.27 yields 4.30/3.11
The 3.70 yields 4.86/3.52
The 3.90 Yields 5.13/3.72
The 4.10 yields 5.39/3.90
Hopefully this breakdown will give some people a little perspective. No matter what, RICHMOND WE NEED GEARS

All this goes out the window once you put a 28 inch slick on the car. :cheers:

[Ktlplxm]

All this goes out the window once you put a 28 inch slick on the car. :cheers:

Not when compared to a 4L60E with 28" tires, but if someone needs that figured out I can do it as well. The factory 26.73 doesn't lose as much height due to sidewall squat as a 28" slick does. While the slick is supporting weight it sits closer 27.25-27.50 (and that is going on the faith that the tire is actually 28" to begin with). Take that into account along with the fact that most people aren't going to drive on the slick, the slick argument becomes a moot point as far as the cruising numbers are concerned. On average the fully 28" tall tire compared to ours only increases the mph at cruise by 2.75-3.0mph which isn't much of rpm increase. :sad:

[GRRRR8]

I am not most people. It will cut the 3.70 a little bit and thats enough for me.

[jakesg8]

I am not most people. It will cut the 3.70 a little bit and thats enough for me.

:charlie3: I love my 3.70's

[Ktlplxm]

I am not most people. It will cut the 3.70 a little bit and thats enough for me.

For the other people who may want the difference in RPM between a 28" and a factory height w/ a 3.70 tail gear:

28" tire, 3.70 tail gear, @ 70mph = 2073rpm
Factory Tire, 3.70 tail gear, @ 70mph = 2171rpm

The 28" tall tire saves you 98 rpm fully inflated
Under vehicle weight (where the height is closer to 27.5) it turns 2110 rpm and thus saves you 61 rpm

I know some people don't like doing the math and I'm bored, so there ya go

[GeorgeInNePa]

Well, I just bit the bullet and ordered a 3.27 differential. I've been on the fence between 3.27s and 3.45s for longer than this thread has been going and I just got my last bit of info tipping me in my final direction. My tune is with Livernois and I checked to see if they have tuned any 3.45s yet and as of today they have not. To me, because they have tuned for 3.27s and because the A6 GXP comes with them from the factory as a good tuning reference, I don't want to risk months of back and forth trying to get the car to drive properly under normal every day driving conditions.

I'm relieved actually. The allure of better performance with 3.45s is what has kept them in the running for so long. But the decision to go with 3.27s I'm confident will keep with what this car (for me) is all about. 99% daily driver with civil manners that is faster than 95% of the cars on the road around me.

Talk to edmanet about that...

[SpeedRacerX]

OP: thank you for spearheading this. Important topic to many.

Since this is not Richmond's thread and they are not a vendor yet, I don't think I'll be offending anyone by asking this...

Given what a whole new diff costs ($1600-$1800 approx), what price do you think the ring & pinion gear sets need to be offered at for it to be worthwhile to buy the R&P and then have the install done?? Assuming you won't be doing the R&P install yourself.

Another way of asking it is...at what price point does it stop making sense to go this route and just install the whole diff?

I'm thinking...unless the R&P is less than $700.00, maybe even less than $600, it might not make sense.

Please chime in with your thoughts. Actually, this would be good feedback for Richmond so they know not only the interest level but also the price point people are willing to pay.

[Ktlplxm]

OP: thank you for spearheading this. Important topic to many.

Since this is not Richmond's thread and they are not a vendor yet, I don't think I'll be offending anyone by asking this...

Given what a whole new diff costs ($1600-$1800 approx), what price do you think the ring & pinion gear sets need to be offered at for it to be worthwhile to buy the R&P and then have the install done?? Assuming you won't be doing the R&P install yourself.

Another way of asking it is...at what price point does it stop making sense to go this route and just install the whole diff?

I'm thinking...unless the R&P is less than $700.00, maybe even less than $600, it might not make sense.

Please chime in with your thoughts. Actually, this would be good feedback for Richmond so they know not only the interest level but also the price point people are willing to pay.

A ring and Pinion, regardless of what rear end housing it actually fits, is essentially the same. A few dimensions are changed, but overall very similar. Having said that, considering almost all the other rear ends in the world (with the exception of a handful) have a ring and pinion price range of 150-300 it really doesn't make much sense for it to be vastly higher. Six hundred should be the max. IMO

[GeorgeInNePa]

The new Camaro gear set has a MSRP around 700 and is currently being sold at just over 600.

Take that for what it's worth. It is what it is...

[Voice of Reason]

OP: thank you for spearheading this. Important topic to many.

Since this is not Richmond's thread and they are not a vendor yet, I don't think I'll be offending anyone by asking this...

Given what a whole new diff costs ($1600-$1800 approx), what price do you think the ring & pinion gear sets need to be offered at for it to be worthwhile to buy the R&P and then have the install done?? Assuming you won't be doing the R&P install yourself.

Another way of asking it is...at what price point does it stop making sense to go this route and just install the whole diff?

I'm thinking...unless the R&P is less than $700.00, maybe even less than $600, it might not make sense.

Please chime in with your thoughts. Actually, this would be good feedback for Richmond so they know not only the interest level but also the price point people are willing to pay.

That played into my reasoning for buying a complete differential. Right now I'm out of pocket about $1850 for a diff/shipping insurance + $90 for poly bushings. When I sell the car (because I won't drive it forever) I'll swap back to stock and sell the 3.27 diff for $1000. For a grand I think I'd have plenty of people interested in a <30k mile differential that offers a jump in performance. So in the end my out of pocket costs will be around $940, or not much more than what the Camaro R&P are going for alone.

[GeorgeInNePa]

That played into my reasoning for buying a complete differential. Right now I'm out of pocket about $1850 for a diff/shipping insurance + $90 for poly bushings. When I sell the car (because I won't drive it forever) I'll swap back to stock and sell the 3.27 diff for $1000. For a grand I think I'd have plenty of people interested in a <30k mile differential that offers a jump in performance. So in the end my out of pocket costs will be around $940, or not much more than what the Camaro R&P are going for alone.

Just one thing. Don't buy parts dependent on what you might be able to sell them for.

If GM brings this over as a Chevy, even just as a cop car, there's a chance there will be more choices for parts in the future.

There is a possibility your diff will be worth nowhere near $1000.

But I hope it will be, because that will mean mine is too. ;)

[GM_Fan]

Chevy could help solve our problems by selling thousands of police cruisers with performance gear sets here in the US. Should make over the counter purchases easier and people looking forward to finding salvage yard gold or buying a retired police car.

[GM_Fan]

I touched base with Richmond today. They haven't made any commitment to make any G8 ratios, but if somebody would buy 40 -50 sets they would get right on them they told me...I wish a sponsor could put some leverage behind this.

Can't say we haven't been trying.

[Voice of Reason]

If/when anyone gets tired of waiting for Richmond I can comment on how quickly you can get a complete diff from JHP. I ordered on their website exactly a week ago today. They waited for the charge to clear until Wednesday to ship it out via DHL. And the DHL guy delivered it to my house this morning. It traveled from Australia to California to Ohio to Central Illinois in less than 6 days. Now that's fast!

I'm installing it this weekend along with BMR's diff and cradle bushings, BMR Trailing Arms, and BMR Toe Rods. I won't be able to really tell how traction is in 1st until April when I switch back to my summer rims/tires, but I'll be able to report back how everything else goes with the install and initial driving impressions.

[GM_Fan]

That is fine if you want 3.27 or 3.7 gears I guess. Once somebody gets around to producing gears we won't have to buy an entire diff from 1/2 way across the world.

[Ktlplxm]

That is fine if you want 3.27 or 3.7 gears I guess. Once somebody gets around to producing gears we won't have to buy an entire diff from 1/2 way across the world.

Maybe not, but if they charge outrageously for the gears, the entire diff is still a better deal. If GM itself will ever come off the hip with the GXP units the problem would be solved easily.

$1800 to my door for a whole piece is much better than $600-700 for just a gear plus install, especially when no one really knows how noisy the gears may be.

***yes I know some don't mind gear whine, but others do***

[GeorgeInNePa]

If/when anyone gets tired of waiting for Richmond I can comment on how quickly you can get a complete diff from JHP. I ordered on their website exactly a week ago today. They waited for the charge to clear until Wednesday to ship it out via DHL. And the DHL guy delivered it to my house this morning. It traveled from Australia to California to Ohio to Central Illinois in less than 6 days. Now that's fast!

I'm installing it this weekend along with BMR's diff and cradle bushings, BMR Trailing Arms, and BMR Toe Rods. I won't be able to really tell how traction is in 1st until April when I switch back to my summer rims/tires, but I'll be able to report back how everything else goes with the install and initial driving impressions.

Good luck with it and be sure to get a new tune for the gear change.

[Voice of Reason]

Good luck with it and be sure to get a new tune for the gear change.

Yep, it's on my list to request the tune change this week. I PM'd with edmanet and I'm hoping that his issues were because he's pushing a lot more power than I am. If not then :boxing:

[Ktlplxm]

Yep, it's on my list to request the tune change this week. I PM'd with edmanet and I'm hoping that his issues were because he's pushing a lot more power than I am. If not then :boxing:

Its in the trans tune which can be bitch to perfect. It may take a few tries to get everything just right, but it can be done

[jakesg8]

I finaly got mine nailed down. It just takes time:cheers:
Anyway there are factory tunes for the 3.27's GXP. If anyone needs one I have one on my HP tuner
And yes the 3.70s with an A6 are a Bitch.