Did you guys put the black plastic underpan thingey on after your install? Seems like it would keep alot of heat in the engine compartment? I can't decide if I want to keep it or take it off. Any suggestions.

 

I kept the pan after going FI. Seems like it does more good than harm.

 

I think its more for splash/rock protection then anything. I would keep it on, especially if you have an aftermarket intake that is outside the airbox and exposed.

 

Besides protecting your oil pan from rocks ect..., it may actually help more air go through the radiator.

 

I'd leave it on as well. Helps with protection from rocks, debris, and road kill. Also helps with aero, and keeping the air from pinballing all over the underside of the engine bay.

 

keep it on for sure. Just experiment on your own by simply going 80 mph to see why. The effects of the underpannel are extremely noticable. I hate driving without one on my car.

Frankly, a flimsy peice of plastic will not protect much. It's all about the aero difference.

 

The stocker is a flimsy POS, after several on/offs it gets warped, or maybe the high speed runs helped distort it Regardless Id run one over nothing. I run a TS front lip that runs all the way under the engine bay....

 

i ended up destroying my plastic undertray.. it isnt the best out there but it is better than nothing.. once i destroyed it, it was time for the arc undertray.. has not broke nor will it ever unless i do something reaaaly stupid

 

also, it forces air thru the IC/radiator, instead of around/under it. Air wants to flow thru the least resistance, and its easy to go around a radiator then thru it without the tray

 

definatly should run it... i mean to run mine but every time i put it on i end up taking it right back off to do something so i havent had it on there for a while now... it can actually help underhood temps anyway, it will force more air to pass around your engine

 

I wish the TS lip/diffuser combo was available for the G. There are plenty of G35 guys that have been threw numerous stock undertrays, and have given up. The only other option is the ARC underpan, but I haven't heard enough on this to be convinced it works any better than the stock undertray.

 

I'm actually looking into having an aluminum underpan fabricated for my car to extend all the way to the back bumper. We'll have to have cut outs for the mufflers, and maybe in a couple of other places. But overall, it should improve the aerodynamics and help me get some additional down force. As I noted in my thread, I'm ceramic coating the entire exhuast system to keep temperatures under control.

I've been talking with Paul at New Wave Fabrication in Boynton Beach, FL. He is a very nice guy, very knowledgable and is reasonably priced. He makes fuel tanks and surge tanks for GT40 replicas, as well as a bunch of other stuff. He also is going to fab a custom search tank for me. I like AAMs, but kind of pricey.

 

i allso dont like the factory one, after opening, u just cant return like it
was befor

Alberto, do u have a pic of that lip ?

 

keep us posted on your undertray thingy. If the price is good, I would be interested in having your shop make one for me too.

 

Will do.

 

i've been running without one for awhile now as i was under the impression that with the heat of being FI, it would allow excess heat to escape the engine better, instead of being trapped in without a way to escape.. hmmm seems from what you guys are saying i was mislead...

 

In a perfect world, run it. In reality, many/most cars I see don't run it. I have driven my Z plenty with and without it, and don't see much difference. Our drag car does not run it, though it does have a good deal of undercarriage covered with an aluminum catch pan.

 

i havent run one for bout 10k miles, drove to florida and back no problems.

 

I always have my pan on. It gives a descent amount of structural support to the front bumper. It also plays a large part in the aerodynamics which is more important the faster you go. It is a ***** getting that thing off just to change the oil.

 

I don't use it at all. After I replaced my front bumper with a C-West N1 it became a major pain in the a$$. I had to fabricate a piece of plastic to make it attach to the front bumper like it does to the stocker and it ripped out at the attachment points. I then figured that it was old anyway and bought a new one from OEM, failed in a week. All I can think is that the N1 scoopes in way more air than stock and ripps the plastic at the attachment points, and let me tell you when the front half pop's out and folds under you don't hear it untill you slow down and it's really ugly sounding.

I've been running without it for about a year now, never an issue. If failing was not an issue I'd keep it, I'd get an ARC if it was not so friggen expensive. A little PITA to remove for oil change but I'd keep it anyway, never took me more than 15 minutes to change the oil anyway.