Opinion: GXP>GT or GT>GXP?

['02 ws6]

There seems to be a pretty big debate going on over on ls1tech but under a thread about the IRS, so I'll ask here.

What's everybodies take on the GXP and GTs?

Is the GXP worth the extra $8-10k with the LS3, brakes, interior, exterior, wheels, etc.

The main thing is everybody throws out the, "I'll throw a Maggie on the GT, make up the cost of the GXP, and dust it."

My opinion is the GXP, with the LS3 outperforming the L76 by over 60rwhp in pure stock form, with the added braking stability, and all the amenities IS worth the extra dough.

My arguement is the Maggie'd GTs I see throw down 440rwhp, that is bolt on territory for the GXP, so would you rather have an FI car w/ stress on the engine (no matter how the tune/install is) or NA when the output is the same?

If the Maggie offsets the cost, GXP owners will spend $2k (est) to get up to the same level.

Now knowing that the L76 and LS3 are almost one in the same, and theoretically you COULD pull the cam and DOD lifters, swap in LS3 valvetrain and be set, maybe lacking 20-30hp due to .2 displacement of LS3, and M6 trans (less parasitic drivetrain loss) due to the intake/heads being the same, but honestly who's going to spend money to do a cam swap and not go radical?! :)

CAI and tune is puting them in cammed GT territory @ 390rwhp compared to 400-410 I see on cammed GT's.

From what I'm seeing from the GXP's I gotta say that it's well worth the money.

[GRRRR8]

It just seems with the lower cost of the GTs its a better deal if you want to go mod crazy, BUT the GXPs are way down from the originally estimated price. I just want to see one on the street. :devil:

[wreckwriter]

GXP engine will be stronger (i.e. harder to break) due to lack of AFM.

[MANOFSTEEL69]

Unless you remove the AFM ;) Bang for modable buck the G8 wins hands down. Our brakes are more than adequate, and I don't see it making that much of a difference. Auto vs manual option....At the strip less chance with the auto of a missed shift, possibly resulting in a major breakdown. No orange color with the GXP like the auto show one....IOM with the 08 GT...I win. :)

[GeorgeInNePa]

A used GT is the hands down best bang for the buck.

A 360hp car with 10K or so on the clock for around $20K? Are you kidding me?

Spend $5K on a forged 416 or 427 short block, put a respectable (not crazy) cam in it, have your heads ported, port the intake and TB, add some headers... You see where I'm going with this?

;)

[99-LS1-SS]

I like the GXP because of the slightly better starting place with the LS3.

[Devilish34]

GXP engine will be stronger (i.e. harder to break) due to lack of AFM.

Exactly even though I (well my wife) broke a 6.2 in less than 8k two exhaust valves snapped while driving our old 07 Yukon Denali to Walmart. But that engine is a beast. I miss that SUV sooo much :( punks in mom and dads Maxima
never knew what hit them when a 6000lb suv smoked them. Oh and I hate her RX400h :puke: sooo much. The 6.2 is a solid motor and I would feel better even with past experience running it balls out over the L76 not that it will stop me :devil: But $ for $ the GT is a better IMO

[xfactor]

For me it was the manual transmission. I always said that if my Grand Prix was rear wheel drive, a V8, and had a manual transmission it would be the perfect car. I also said that I would keep my 99 Grand Prix for 10 years. Well, Pontiac must have had a microphone in my car because the GXP came out just in time. In fact, I had my Grand Prix 10 years and 2 weeks and then replaced it with the GXP. It's like going from a Big Wheel to a Dirt Bike:)

[norm8332]

If you have the cash get the GPX. It is a better starting point for sure. If you can afford it start with the GXP.

That said you could get nearly 500whp from the GT for about $8500 while keeping AFM.

['02 ws6]

A used GT is the hands down best bang for the buck.

A 360hp car with 10K or so on the clock for around $20K? Are you kidding me?

Spend $5K on a forged 416 or 427 short block, put a respectable (not crazy) cam in it, have your heads ported, port the intake and TB, add some headers... You see where I'm going with this?

;)


See now your talking!:woohoo:

I'm waiting the day where someone has a TSP - Texas Giant cammed/l92 headed 414cid monster, idling like a big block, in a GT!:)

[Eidolon]

I would say GXP>GT for several concrete reasons. That is, these are the reasons I would buy the GXP instead of the GT.



Default suspension tuning is tighter and sportier. You can certainly get the same or better with the GT, but you have to spend additional monies.
Manual transmission. For me, this is a big one. I want to have the control and pleasure of rowing my own gears. Heel-and-toe, anyone?
Brakes.
The difference between the GXP and GT in this regard cannot be overstated, and it has nothing to do with braking distances. I wouldn't expect to see a difference in stopping distance from 60 mph because that will be more tire limited, nor will most of us explore the heat capacity of the stock rotors/pads in even the GT. No, what makes the difference is the feel of the brakes in the GXP. In the GT that I test-drove, the brake pedal was old-Buick-squooshy, with no increase in pressure as you pushed it to the floor. I came to a hard stop at a light in the GT simply because I had no idea how to modulate the brake pedal because it was so lacking in feel. Oh, but the brake pedal in the GXP... Now that was a nice brake pedal. Light effort, solid bite, and good linear increase in resistance as I pressed it toward the floor. I knew how that pedal would control the car the instant I used it.
If you want to add forced induction, the LS3 block is stronger. As I recall, they're actually sharing this block with the LS9 engine, now, so you're getting the LS9 block without the LS9 Roots-type supercharger. So the LS3 should handle forced induction very well. No idea if the same block is used with the L76; and take this particular point with a grain of salt!
Even if you don't intend to add FI, the character of the LS3 bone stock is immensely meaner and more downright evil in demeanor than the L76 in the GT. I remember when I test-drove the GT, when it was idling the car was quite settled. When the GXP idles, however, the entire car settles, and then shakes as the engine idles; settles, then shakes. The engine is tuned to run in higher RPMs, and so it idles roughly. The entire car literally shakes with the waiting power under the hood. I love it. And the tone of the engine... A roaring crescendo of sonorous fury. Again, love it.

So yeah, I would say the GXP>GT. But one could certainly modify the GT to have the exhaust and idle character of the GXP, and you can add FI to the GT to more than match the stock output of the GXP. There's no difference in tires or really in the interior, and the brake rotors are already sufficient in the GT, as most any review of the G8 GT you can find online will attest.

So if I had to boil it down, there are two reasons I would (and WILL) get the GXP instead of the GT: manual transmission, and the greatly improved brake pedal feel. If I can add a third reason, the power surplus at stock tunings is it.

Oh, and I like the subtle change in looks of the GXP better. :)

[GeorgeInNePa]

See now your talking!:woohoo:

I'm waiting the day where someone has a TSP - Texas Giant cammed/l92 headed 414cid monster, idling like a big block, in a GT!:)

If my house would sell, you'd get to see what a 416 would do in a black GT.

;)

Click the WANT! in my sig.

[99-LS1-SS]

I remember when I test-drove the GT, when it was idling the car was quite settled. When the GXP idles, however, the entire car settles, and then shakes as the engine idles; settles, then shakes. The engine is tuned to run in higher RPMs, and so it idles roughly. The entire car literally shakes with the waiting power under the hood. I love it. And the tone of the engine... A roaring crescendo of sonorous fury. Again, love it.


I like the way the LS3 shakes at idle. It makes me feel like I have a baby cam in there.

[flomofo]

The GT shakes as well actually. My GT does anyway.

[-Ray-]

They all shake. LOL

[99-LS1-SS]

Dammit! I thought I was special! :(

[bigtreepu]

You are special.....It's just not in the "only my car shakes like a badass engine is underneath the hood" kind of way. lol.
Anyway, Dollar for dollar they are both awesome cars. If you need a manual and like the better suspension and much better brakes, then a GXP is in order. If not, go w/ the GT.
~Matt

[p71]

when I am done throwing the extra 8K at the car the GXP will not touch me in a straight line or around corners. It will be close but not a match in braking and apperance... the interior on the GXP may be a little nicer...

Still no manual though.

[nosbusa1500]

If your looking to have one of the fastest G8's around, then I would pick up a used GT for around 20k. Throw in a crate motor, supercharger, or both. If you don't like the GT, then I would find a good deal on the GXP.

In my area the GXP's are going for sticker and over in some cases. Me personally I'm not going to spend 50k plus for a GXP & mods. For that type of money I would buy an 09 CTS-V if available.

[99-LS1-SS]

.. the interior on the GXP may be a little nicer...

Still no manual though.

Only the embroidery on the seats.

[99-LS1-SS]

You are special.....It's just not in the "only my car shakes like a badass engine is underneath the hood" kind of way. lol.

~Matt

LOL! Thanks.....uh....:wacko:

[p71]

Only the embroidery on the seats.

nah, you also get the $5,000 dash...

[99-LS1-SS]

Yeah, I forgot about that.