Intake ideas

Have read several treatises on relative high pressure areas in the wheel well, especially at the top and top/rear of the tire.

With all the projects trying to get cooler air from the fender well, but still dealing with hot air intruding into the fender from the engine compartment, I wonder if anyone has considered pulling air from the wheel well directly via piercing the fender liner? This should be cooler air than the inner fender, and the relatively higher pressure air could help with induction.

One would probably want to create some louvers and a baffle to eliminate any water induction, but I think it could be very do-able, even via a ducted extension from the stock airbox possibly.

Al

Seems like an easy enough experiment. Mount the intake filter close to the fender, cut the vents in the fender, but block off for the first test run, measure IAT. Then open the vents and retest IAT.

I have a concern about this mod: I don't believe the pressure under the front fenders is greater than the pressure under the hood. The reasoning is that the pressure under the hood comes from air being fed through the front intake, through the radiator, etc. That air gets trapped and really has nowhere to escape, even with the cowl seal removed. It may go out the bottom of the car near the rear of the engine bay, not sure.

The wheel wells don't get quite as much air, imo. They get more than enough to supply the intake, but not enough to displace the engine bay pressure. This is speculative, but here's an instance of RX-7 owners trying our experiment is reverse: cutting vents in their fender linings to let engine bay air escape into the wheel wells. One guy even claimed reduced acceleration times due to less drag!

http://www.rx7club.com/3rd-generation-specific-1993-2002-16/how-mesh-fender-liner-inserts-engine-bay-889283/

"Way back in 1995 when I did a lot of testing on my first FD, I had found that cutting both of those wheel well areas out and replacing the plastic with an open wire screen, actually reduced my 60 - 160 MPH acceleration times a full 1.5 seconds. That is a HUGE gain in anyone's book. It was tested 4 times and results were consistent.

Thus, my conclusion is that removing those liners drop pressure build up inside of your engine compartment which, also should allows for a much better exchange of air as it is allowed to flow through instead of being trapped underhood."

Understandably, there could be differences between an RX-7 and Riviera. Who knows, maybe you're onto something?

That's actually really interesting. I can't wait to see where this goes.

I'd consider doing it at some point - not to feed the intake, but to relieve high pressure from under the hood; also to assist with brake cooling.

http://www.thirdgen.org/techboard/brakes/689320-brake-cooling-through-rad.html

isn't the ultimate solution simply relocating the turn signals and use the space made as air ducts?

Yes, but if you do it 'simply', it's going to look ugly, imo. To do it right, it would involve a new design, bumper work, and re-fabricated signal lens (lots of work).

If you think about how the factory would do it, they probably wouldn't change the signal locations, because there's only a need for intake on one side of the car. For example MB modified the fender of the 250D Turbo by adding these vents. It makes sense: nice and high to avoid water intake, and it pulled air from the side rather than the front. They understood how the cold air intake principle works - pulling from the side means less water and debris ingested, and there's really no such thing as "ram air". An FI engine's intake is going to suck in more air than any frontal intake duct will cram into it.

nah, just put mesh in place of the turn signals, a thin porous sponge to catch/break up moisture behind that, find/make a NACA duct to route the cool air, then mod the side lamps into turn signals and you're all set.

Added to my previous post. ^^^

Yeah, I guess you could change the corners into signals. Nice idea if you won't miss the side illumination feature. I say do it, charlieRobinson!

I think on 2 or 3 occasions, I have appreciated my side lamps.

It's taking me forever to do anything with this car. slow but sure process, tho.

Hey Greg What size tubing did you use to be able to use the original opening? Im thinking about going FWI finally. I've got the gutted Stock with K&N currently

Hey Ruben. I used the parts I had to eventually make a fwi. I bought this ducting that is 4inches in diameter. http://www.spectreperformance.com/index.php/catalog/air-intake-components/air-ducting-components/4-duct-components/air-duct-hose-4-o-d-black.html

It comes with 2 threaded couplers. You will want to attach one to the side that you want to attach to the throttle body. the other side of the ducting you sort of screw into the hole in where the airbox used to be. The tricky part to explain is how you get the 4 inch ducting with the coupler on to fit on the 3.5in throttle body. When you buy a spectre cone filter you you get a coupler that goes inside the filter to fit it to a 3.5 in ducting. You take out that coupler and put that in the coupler that goes over the throttle body. Then you place the 4 in filter over the ducting that is in your fender well.

That spectre ducting you have is ~3.5" ID. The OD is 4".

Part # : 9751
Application:
Air Duct Hose - Black - 4" O.D.

yall should know what youre getting unlike me who wasnt paying attention.

chitown_riv98 wrote:

Hey Greg What size tubing did you use to be able to use the original opening? Im thinking about going FWI finally. I've got the gutted Stock with K&N currently

You can just go to Lowes/Home Depot and pick up some drain tubing (make sure to get the NON-perforated). It's ~$10 for 10ft and works just as well. You can also just get some PVC piping and make your own. It's smoother, so it should allow slightly better flow but the drain tubing looks better and is easier to work with.