Lower Panel Modification

[GRRRR8]

This panel is located underneath the air intake system. By modifying this panel it drastically increases the amount of air to your air intake kits. Appox. time to perform mod. 1.0 hrs Necessary tools: Utility knife or drill holes and use hacksaw blade with handle.

http://i295.photobucket.com/albums/mm132/charlesvanwormer/DSC03660-1.jpg

[SRG963]

Another Dimension to GRRRR8's Wonderful Lower Panel Mod.

I would suggest you cut from the top of the panel, inside the engine bay if you are able. This way you can tell where you are cutting and the exact size you need.

Instead of cutting out the lower panel completely, you can cut 3 or 4 lines into the panel forming an "H" like shape. You can then fold the front piece back and out of the way, and use the back plastic lip for a little scoop action. Granted your opening will not be a large as the original GRRRR8 LPM, but this will allow you to fold the plastic back for winter weather conditions. You can also place a piece of plastic/rubber over the LPM (from inside the engine bay) to cover the opening for bad weather conditions.


http://i297.photobucket.com/albums/mm227/srg963/P6270042.jpg

http://i297.photobucket.com/albums/mm227/srg963/P6270041.jpg



and here's a pic from inside the engine bay from above looking at the panel you cut (from top)
http://i297.photobucket.com/albums/mm227/srg963/2317806CopyofairinletLarge.jpg
the factory snorkel sits right above this panel. as you can see I cut from the bottom :(
http://i297.photobucket.com/albums/mm227/srg963/P8130082.jpg
see DIY for the factory snorkel mod.

[GRRRR8]

That works too!

[Chewy]

Another Dimension to GRRRR8's Wonderful Lower Panel Mod.

Instead of cutting out the lower panel completely, you can cut 3 or 4 lines into the panel forming an "H" like shape. You can then fold the front piece back and out of the way, and use the back plastic lip for a little scoop action. Granted your opening will not be a large as the original GRRRR8 LPM, but this will allow you to fold the plastic back for winter weather conditions. You can also place a piece of plastic/rubber over the LPM (from inside the engine bay) to cover the opening for bad weather conditions.</div>
This is something I plan to do when I get mine. My plan is to make it so I can drop something down there so not to suck up snow in the winter.

I would also like to look into using some aluminum sheet on a brake and bend something into a scoop and mount it under there. We'll see what can be done.

[allencga]

Bet you could build an electrical mechanism that could be controlled from the drivers seat that could be used to deploy a door in the panel downward like a mini scoop. It could be retractable in wet weather the keep water from getting drawn into the intake. If the door was hinged along its back edge closest to the tire, an electric solenoid or similar could be used to open it downward at maybe a 20 degree angle to act as an air scoop.

[GRRRR8]

Hey Allen&#33; I am thinking of doing a vacuum operated actuator. As it goes wide open, a door opens and at slow speeds it shuts. Water is not an issue. Its too far from the inlet. Some are worried about snow packing up in there in bad weather.

[wreckwriter]

<div>
(GRRRR8 @ Aug. 13 2008,2:30)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">Hey Allen&#33; I am thinking of doing a vacuum operated actuator. As it goes wide open, a door opens and at slow speeds it shuts. Water is not an issue. Its too far from the inlet. Some are worried about snow packing up in there in bad weather.</div>
You could use the motor and actuator from an old vacuum headlight system I bet. Its an interesting concept.

[GRRRR8]

Looking at the ones from a Cowl-Induction hood.

[allencga]

That vacuum actuator concept is a good idea, and you could use a small solenoid valve(egr solenoid?) in the vacuum line to control exposure to manifold vacuum. you could spring load the hinge to close the door automatically when vacuum is cut off. Don&#39;t think snow will be too big a problem as long as you don&#39;t go plowing through snow banks, but vacuum hoses and actuator may need to be protected from icing in cold weather. Spring to close flap will need to be fairly strong as ram air will tend to force the flap open. The points of attachment for the hinge will need beefing up too. What about sheet aluminum for the door/flap? Think someone else may have mentioned that.

[GRRRR8]

For those that dont Allen I have known him for 12 years. Very smart&#33; He sees things much like I do. I had him come to Ga while I was there and now I am back in Tx. Wish he was here. I could come up with an idea and he would be the one to fab it up. Get your ass home Allen&#33;

[Tommy G]

Has anyone thought of using NACA ducting for this? Its the same as what NASCAR uses for fresh air intake.

I was thinking that you could make something out of one of these:

http://www.stockcarproducts.com/brkduct.htm

or this?

http://www.pegasusautoracing.com/productselection.asp?Product=3629

http://www.pegasusautoracing.com/Images/L/3629.JPG

How about this:

1. cut a hole in the stock plastic to fit one of those NACA duct openings
2. get some stainless hardware cloth, cut to fit over sized around the intake the duct
3. sandwich the hardware cloth between the opening in the stock plastic opening and the NACA duct
4. drill holes for your favorite mounting - speed clips, rivets, machine screw etc.

Then you would have a 3" or dual 3" or 4" duct delivering fresh air directly to your CAI! The hardware cloth would also prevent road debris from getting in too easily. Thoughts?

[GRRRR8]

It just hang down too far. Very limited clearance. I might try and see if I can recess something like that, but it might not be a DIYer project.

[Tommy G]

Not sure you get what I'm saying. NACA ducts do not protrude from the exterior. They are designed to draw air in without sticking out and have a flush fit w/the exterior bodylines. There would be no protrusion, just flush with the lower under air dam where you guys have already cut out.

all from wiki: http://en.wikipedia.org/wiki/NACA_duct

Ferrari has used it extensively:

http://upload.wikimedia.org/wikipedia/commons/thumb/3/3e/Ferrari_F40_in_IMS_parking_lot.jpg/800px-Ferrari_F40_in_IMS_parking_lot.jpg

And jet engine cowling:

http://upload.wikimedia.org/wikipedia/en/d/de/NACA_submerged_inlets.JPG

[wreckwriter]

I think this would work. All we need is a duct to connect to the triangular lower "snorkel" thing of the Roto-Fab and to this on the bottom end. Yea, we could just add these and improve flow but with a duct it would be so much more.

Can these be had?

[Steve]

looks interesting

[Tommy G]

Just google naca duct. Lots of suppliers for for the duct and high quality hose. The first link I posted has a 4 x 6 intake with 3" or 4" hose connection that would fit with room to spare. If I had a stack of different sized NACA intakes, I would try to find one that fit perfectly in that lower panel. Obviously I do not have a stack of different sized NACA intakes, its hard to tell what would fit properly.

This is just an idea that I had floating around for awhile. I was considering using the stock airbox. I'm hoping that the 4" tubing would fit around the inlet with a little modification after removing the factory tube that protrudes forward from the stock airbox.

[wreckwriter]

I think it has possibilities. i used to work on aircraft, have seen thousands of these things but never knew the name nor thought of it for this application.

[GRRRR8]

Great idea! I am going to get some measurements and follow up.

[Steve]

Some more:
http://www.racerpartswholesale.com/product/2146/Naca_Ducts2
http://www.racerpartswholesale.com/product/2139/Naca_Ducts2
http://www.racerpartswholesale.com/product/2148/Naca_Ducts2
http://www.racerpartswholesale.com/product/2141/Naca_Ducts2
http://www.racerpartswholesale.com/product/2147/Naca_Ducts2

Would think a 'single' hose setup should be sufficient when you look at how
relatively small the inlet area is on the Roto-Fab?

Always had something like this is mind so i'm glad i'm not the only one :)
Now who's gonna be the first to try?

[wreckwriter]

Some more:
http://www.racerpartswholesale.com/product/2146/Naca_Ducts2
http://www.racerpartswholesale.com/product/2139/Naca_Ducts2
http://www.racerpartswholesale.com/product/2148/Naca_Ducts2
http://www.racerpartswholesale.com/product/2141/Naca_Ducts2
http://www.racerpartswholesale.com/product/2147/Naca_Ducts2

Would think a 'single' hose setup should be sufficient when you look at how
relatively small the inlet area is on the Roto-Fab?

Always had something like this is mind so i'm glad i'm not the only one :)
Now who's gonna be the first to try?

How would you even hook up a 2 hose? I think it needs to be ducted to the intake, not just fed into the compartment, to be most effective.

[GXPaycheck]

I found a couple of marine type clamshell vents which should fit over the holes I drilled in the lower panel.
Marinco #n10873, abs plastic. Should be enough to guide some cool air into the intake compartment. Also say a snorkle type vent at the boat shop that looks interesting. Might hang a tad too low though. Can't wait to get home and see how it fits!
:repair:

[Steve]

How would you even hook up a 2 hose? I think it needs to be ducted to the intake, not just fed into the compartment, to be most effective.


yeah no idea - you'd have to basically merge them.. seems a little silly.
I'll probably try one of those ducts, get some hose, and just run it up to the bottom of the roto-fab, somehow attach & seal it and call it good enough.
Just not sure what kind & size to get.

[wreckwriter]

yeah no idea - you'd have to basically merge them.. seems a little silly.
I'll probably try one of those ducts, get some hose, and just run it up to the bottom of the roto-fab, somehow attach & seal it and call it good enough.
Just not sure what kind & size to get.

Me either yet. The triangular shape of the inlet on the RF makes it all challenging.

[JDP G8GT]

You know GRRRR8 has to be excited about those wholesale tiewraps!!!:rofl:

[GRRRR8]

Man! I am going to be 60 and still hear about my ties! I am going to put clothes pins on something to get you to forget! LOL

[G8GTlawride]

Has anyone thought of using NACA ducting for this? Its the same as what NASCAR uses for fresh air intake.

I was thinking that you could make something out of one of these:

http://www.stockcarproducts.com/brkduct.htm

or this?

http://www.pegasusautoracing.com/productselection.asp?Product=3629

http://www.pegasusautoracing.com/Images/L/3629.JPG

How about this:

1. cut a hole in the stock plastic to fit one of those NACA duct openings
2. get some stainless hardware cloth, cut to fit over sized around the intake the duct
3. sandwich the hardware cloth between the opening in the stock plastic opening and the NACA duct
4. drill holes for your favorite mounting - speed clips, rivets, machine screw etc.

Then you would have a 3" or dual 3" or 4" duct delivering fresh air directly to your CAI! The hardware cloth would also prevent road debris from getting in too easily. Thoughts?

I have been wondering where to find these! I have looked at ducting companies for the flange to attach to the lower panel and either a stainless flexible duct or a silicone one to attach to the air box ( I want to retain the stocker). Remove the factory ducting and rivet solid plate over odd shape hole and then fit this type flange or a plain duct flange. Run the flexible ducting to the NACA duct that is attached to the lower panel. Possible? From the pics I see about the panel mods, it looks to be a straight shot from the air box to the panel and not very long. Only one bend, at the box. Would a 3" duct be enough though on an enclosed box, either stock or Roto?

[GRRRR8]

Most cold air/ram air systems use 4-5 inch dia hose. I will be looking for 5in on one of those ducts.

[G8GTlawride]

I think this would work. All we need is a duct to connect to the triangular lower "snorkel" thing of the Roto-Fab and to this on the bottom end. Yea, we could just add these and improve flow but with a duct it would be so much more.

Can these be had?

I do not have one of the intakes you have so bear with me. But, can't you just block the triangle off with a flat piece of plastic and then re-configure with a round flange? Cut the new hole the size of the duct you want to run.

BTW, how did you fare with the storm? It stalled over Titusville where I am and caused the roof to leak over the kitchen. Now need to fix roof and new drywall!

[GRRRR8]

I am going to use a heat gun a 2 rings to reshape it then attach hose. I saw this AM about your roof. That sux! I had the same exact thing happen in Ga. We had a lot of rain today, all day!

[G8GTlawride]

Great idea! I am going to get some measurements and follow up.

Since you have intimate knowledge of these lower panels and that area in general, What size hose would adapt to the factory air box, using a custom flange? And what are the dimensions of the area you cut out of the lower panel to expose the filter to fresh air?

Don't want to order several diff sizes if you know what I mean. I'm thing the small square one with the 4" hose nipple would work.

[G8GTlawride]

Sorry for the grammer! The dripping water from the roof leak into my kitchen has me going NUTS!

[GRRRR8]

I would say if you could get a 5 that I know for a fact is plenty up to 500/500. The reason I know is I had an ATR set up on my Buick and was 5in. If you block the fender in let in the box definitely use a 5in.

[G8GTlawride]

I would say if you could get a 5 that I know for a fact is plenty up to 500/500. The reason I know is I had an ATR set up on my Buick and was 5in. If you block the fender in let in the box definitely use a 5in.

Thank you. What are the dimensions of the area you are cutting out of the lower panel? It looks irregular but large enough to accommodate at least the
4" flange, maybe 5. The mounting flange could certainly encroach on the other side of the frame rail as long as the inlet is in the area where the hose needs to be.

[GRRRR8]

That 1 alum duct is almost the exact shape. I would say 4 x 6 easily will fit.
If you have to use the 3in hose, keep the fender inlet open for sufficient low speed air flow.

[todds87ss]

How would you even hook up a 2 hose? I think it needs to be ducted to the intake, not just fed into the compartment, to be most effective.

use caution when direct ducting...water needs to have a place to go. If the easiest place to flow is into the air inlet, that's where it will go. Then...bye bye motor...:stretcher:

[wreckwriter]

use caution when direct ducting...water needs to have a place to go. If the easiest place to flow is into the air inlet, that's where it will go. Then...bye bye motor...:stretcher:

Keep in mind this will be close to 2 feet, straight up. I don't really think this is likely to occur unless you're trying to ford a river.

[todds87ss]

Keep in mind this will be close to 2 feet, straight up. I don't really think this is likely to occur unless you're trying to ford a river.

Talk to all the folks who've had hydrolocked motors with fast toys ram air, and driven into water just to the opening 10 or so inches (...if the throttle opens, 14 inches of vacuum will draw water up 14 inches and that makes 24 inches total. It will actually pull water up farther since the Internal Combustion motor is a positive displacement pump.

Most good ram air systems have a place for water to go in this instance. I would never completely seal one off, at the risk of the motor. No benefit and a lot of risk. I say no benefit to sealing up because we are not talking about a closed system. The inlet side is open to the bottom of the car, so the ideal gas law does not apply. Your power increase will be max as long as your inlet is at least as large as all of the openings combined. Using 6 square inches for the throttle inlet pipe, add all of the other openings. If I was to fab up a box, I would leave a 2 square inch opening near the top but under the filter elevation. Then cut a 10 or so square inch opening, perhaps larger to take advantage of the stagnation pressure at the front of the air dam.
just my .02:twocents:

[G8V8]

Good write up Todd. In another thread I posted that I thought a tube from the lower panel up to and surrounding the triangular inlet of the Roto-Fab but not sealing against it would be a good idea. I thought the gap between the larger round tube and the triangular inlet would make a sort of vacume break that would prevent water from being drawn up that high while not having much effect on the inlet air given the large pipe and cut out size relative to the size of the vacume break.

[wreckwriter]

Sounds like you know what you're talking about and we should drop this line of thinking.

[todds87ss]

Good write up Todd. In another thread I posted that I thought a tube from the lower panel up to and surrounding the triangular inlet of the Roto-Fab but not sealing against it would be a good idea. I thought the gap between the larger round tube and the triangular inlet would make a sort of vacume break that would prevent water from being drawn up that high while not having much effect on the inlet air given the large pipe and cut out size relative to the size of the vacume break.

sounds about right to me...

[blackbirdws6]

Why not some solenoid type setup with a WOT activation switch like a nitrous system?

[Panther 2]

:cd:Blackbirdws6, good to see you here.

[Featherburner]

Why not some solenoid type setup with a WOT activation switch like a nitrous system?
Damn Brian, where have you been.

[roSSco]

I did this today and used a 4" hole saw I had from another project. It worked great! or is that GRRRR8? :D

http://www.anotherls1.com/pics/G8/DSCF0395.JPG

http://www.anotherls1.com/pics/G8/DSCF0396.JPG

[roSSco]

I made a scoop tonight and came up with a way to block the hole. I'm pretty proud of myself. :D

I took some cardboard and made a pattern. Then cut the pattern out on some thin sheet aluminum.

5.5" long
http://www.anotherls1.com/pics/G8/DSCF0399.JPG

5.5" at the "rear".
http://www.anotherls1.com/pics/G8/DSCF0400.JPG

9.5" at the "front".
http://www.anotherls1.com/pics/G8/DSCF0401.JPG

Bent to shape...4" in the center section to match the hole.
http://www.anotherls1.com/pics/G8/DSCF0402.JPG

On the car.

http://www.anotherls1.com/pics/G8/DSCF0397.JPG
http://www.anotherls1.com/pics/G8/DSCF0398.JPG

Now the plug.

I kept the piece that was cut out and placed a thin strip of metal ~1" wide and 6.25" long and drilled 3 holes. One at each end and one in the center. I decided to mount the center with a wingnut so I could fish it into the hole more easily. I then attached the nuts with the bolts and secured the nuts with J.B. Weld. Waited for it to dry and now I can fish it into the hole and secure it via 2 holes that correspond to the bolt locations. I hope to have pics of it installed tomorrow night (it's supposed to rain). ;)
Here's a couple of pics of the plug off of the car.
Bottom view.
http://www.anotherls1.com/pics/G8/DSCF0404.JPG

Back view.
http://www.anotherls1.com/pics/G8/DSCF0405.JPG

[SRG963]

I made a scoop tonight and came up with a way to block the hole. I'm pretty proud of myself. :D

As you should be...looks like a lot of work.

Have you stuck your hand out of the window while driving 60 MPH? How about 80? 90? How did it treat your hand at that speed? What do you think the wind will do to a scoop at that speed? Do you have tire protection for screws? LOL

The good news is that the scoop is not necessary. I used part of the oem plastic panel to form a scoop when I did mine (see picture below), and after a couple weeks, I straightened it back out just to a hole. Reason? I was finding rocks, leaves, and all sorts of other shit trapped to my filter. I had also make a panel to block off such things from making it past my filter into my engine bay which was luck.

http://i297.photobucket.com/albums/mm227/srg963/P6270042.jpg

The CAI's don't need a scoop, just some fresh air. The air will find it's way into that hole at speed.

I really like your hole and plug Idea though....very smart!

[wreckwriter]

I agree with SRG, I think the scoop will blow down and off at speed.

[roSSco]

Top speed so far is 75mph and all is well. :D

I also drove in torrential rain for 15 miles at highway speed w/o any problems. ;)

[MtbDoc]

I realize that all of you N/A guys are moving past this approach, but given the intake for the Maggie, I am thinking through how to improve airflow. As I noted in another thread, I really don't believe that there is much to be gained by changing out the airbox (to a RotoFab, for example), PROVIDED that the inlets to the stock box are opened up.

QUESTION: how would you think this would work best to allow improved airflow THROUGH the stock setup (perhaps w/ a K&N filter)? Simply cut some holes in the stock one? My contention is that the RotoFab helps mostly through a smooth, curved hard pipe, coupled with a higher flowing box. Given that the Maggie pipe has to be used, it seems that the stock box (with some holes opened up) + lower panel mod would do fine.

Of course, I suppose I ought to hook up a vacuum gauge to the airbox and run the car; make the mods and repeat. See what is what.

THOUGHTS???

[PantherGTBlack]

I agree with SRG, I think the scoop will blow down and off at speed.


Or it will get molested by those damn driveway curbs, the rolled that evil kinevil used for ramps, lol.

[MtbDoc]

I realize that all of you N/A guys are moving past this approach, but given the intake for the Maggie, I am thinking through how to improve airflow. As I noted in another thread, I really don't believe that there is much to be gained by changing out the airbox (to a RotoFab, for example), PROVIDED that the inlets to the stock box are opened up.

QUESTION: how would you think this would work best to allow improved airflow THROUGH the stock setup (perhaps w/ a K&N filter)? Simply cut some holes in the stock one? My contention is that the RotoFab helps mostly through a smooth, curved hard pipe, coupled with a higher flowing box. Given that the Maggie pipe has to be used, it seems that the stock box (with some holes opened up) + lower panel mod would do fine.

Of course, I suppose I ought to hook up a vacuum gauge to the airbox and run the car; make the mods and repeat. See what is what.

THOUGHTS???

Come on guys, someone have a look AND comment on this!

[Gearhead]

I just did the lower panel mod by drilling numerous holes below the CAI filter to allow improved air flow. I understand the benefit on paper. Has anyone done a before and after at the dyno or track? Just checking to see if anyone has numbers showing whether it really makes any difference up top?

Jim

[roSSco]

I made mine so it could be completely blocked off. I intend to make some back to back runs soon.

[Gearhead]

Cool. Please post any results you see. I'm just curious if it's worth a tenth or a mph.

[T1000]

Hey guys new to the board, but a quick question with the snorkel and lower panel mod do you need to retune the car or disconnect the battery for the computer to re-learn?

[GRRRR8]

No, you are good to go!

[T1000]

Thank you, I just recently purchased a G8, going to do this mod this weekend. Thanks again.

[MIEngineer]

I may mess around with this in the spring:

I have a two channel hand held data logging thermocouple set up that drops into excel...also a manometer that can do the same.

I was planning on playing around with the temps in the stock airbox against the Rotofab against my SLP intake [unless i sell the SLP by then]. Just bought them to test out some ideas against ambient / engine bay temps. Since it is two channel, i can just do straight temperature differentials for the systems.

Should be fun...

Also if you guys want to plug a hole [i like that idea vs cutting out the entire area], you could plug any size hole by just cutting some scrap black plastic from a junkyard, or thin metal/aluminum or plexiglas even...just go 1" oversize than the hole, use two pieces and sandwich the opening in the middle. This idea works for any size/shape hole too...just leave extra around the edges [if you didn't cut out everything to the edge in the panel]. Line it with self adhesive thin rubber or foam so it seals it a bit if you want.

If you run a large tube from a duct up and worried about sucking up water [as I've seen happen to a lot of friends cars over the last 15 years]...you could use something like what AEM offers:

http://www.aemintakes.com/air_bypass_valve.htm

Just some ideas for those worried about weather conditions.

[-Ray-]

I'm willing to swap my modified lower panel for a stock one. No longer using a RF for a CAI.

[WickedMom]

I'll swap with you ray. I just got a brand new lower panel and I lost my modded one to the mattress


Sent from my insanely great iPhone 4s using Tapatalk

[STL_G8GT]

I'll swap with you ray. I just got a brand new lower panel and I lost my modded one to the mattress


Sent from my insanely great iPhone 4s using Tapatalk

Giving it all up on the mattress, huh.

[GRRRR8]

Just an FYI: there is a thread where I tested this with a thermocoupler and the results. IATs dropped way faster with the mod. If you block off the inner fender so the hot air from the radiator/fans cant get to your CAI it is even better.

[MIEngineer]

Interesting...

Have a link ?

[edmanet]

Just an FYI: there is a thread where I tested this with a thermocoupler and the results. IATs dropped way faster with the mod. If you block off the inner fender so the hot air from the radiator/fans cant get to your CAI it is even better.

I have this mod. It works. ; - )

[-Ray-]

It does work. I just have a Vararam now and don't need to the modified panel.

Sending you a text Jessika.

[MIEngineer]

I'm not saying it doesn't :) Call it my inner nerd that just wants a reason to mess with the intake systems...