mark21742

I have the tunnel and floor cut out of my 04 GTO right now and getting ready to install a full ten point cage to go with my new back half 9" Ford rear and 4 link.....


My question is when I run all my new floor bracing and cage supports and framerails I was thinking of laying the new floor from under the car so the dupports would all be on the inside and give me a flat underside......do you guys think this would give any gains or faults?

ANTICOP RAM AIR

iTrader: (7)

probably not.. just making a flat center section wont do anything, you would have to do the rear valance, fender wells and anywhere else that would create drag. It will look nice though.

mark21742

See, that's what I was thinking, thin aluminum cover under the trans tunnel, engine compartment and run all the way under the back of the car....on jackstands with the suspension fully extended the only place the hangs below the floor is the bottom of the 9" pumpkin since I raised everything up for the big new tires to fit up in the quarters and have the car for level......right now I'm running a 31-18.5 15, but setup to take a 33-22.5 15 when these tires wear out.

chuntington101

one thing to think about would be cooling air! if you flat florr the car where is the engine bay air going to go? Is it just going to stack up in the engine comartment and thus slow air through the rad / intercoolers??.

Flat floor should make the car more slippy but you have to allow the hot air out the engine bay. Ventted hood & cut out behind front wheels can be used to help evacuate the hot air. This in itself can help the aerodynamics of the car and also help suck air through the engine bay if done correctly....

Chris.

mark21742

I have been thinking about the cooling.....mostly thinking hood vents towards the back of the engine bay....two large ones, one on each side.....think that would give enough airflow?

chuntington101

I would keep tehe air vents as far forward as possiable! As you start to approach the windshield area you go the higher the air presure. So when you start curtting holes in that area you get reverse airflow which is not going to help shifting air out from under the hood! lol

If you look at race cars they all tend to run the hood vents far forward. They do often run vents form the rad to the hood. as said this really helps with airflow over the car. You could also use a front spliter to help feed cool air to the rad! both the top side and the bottom side could be used to pull more air into the rad.

I guess you need to understand the ccooling requirements. If you can get away with little tyo no air entering the front themn you might as well do that! you only want to duct or move the air that you really need to. Whats the use of the car (guessing drag race)?

chris.

mark21742

Basically building a full on drag car that I can enjoy driving on the street when I get the urge.

I figured is ask this here and now because at the moment the car has no floor in it from just below the firewall to the back bumper. I back halfed and rubbed the GTO with a Ford 9" solid axle, 4.56 gears and 4 link, and am finishing the installation of my NHRA legal 10 point cage.

3 speed manual, 12.5:1 pump gas 408 stroker, 255/263 .624/.624 115 lsa cam.

chuntington101

I say if you can do it right you might as well do it! Would look really cool and its not going to do any harm.

Oh and be sure to post up some pics!

mark21742

The kids are leaving tonight and the wifey works, so its garage night for me! I hope to get the floor and trans tunnel fabbed and in tonight

chuntington101

You better post pics! lol

mark21742

The main floor/ tranny tunnel skeleton is finished with the exception of front just behind the shifter to under the dash, so after nap time I'll cleanup the firewall and weld in four short peices of small angle iron.