Marlon

Looks to me that the air intake is sucking a lot of hot air even if the car is flying down the road. That area on the deck lid looks like it might have a pretty good laminar flow down the rear window onto the deck lid. Looks like one could fabricate a little rubber inlet that you can merely slide into your existing 2" X 4" inlet to catch that high flow of cool air. The thing would 'face' up and nearly touch the underside of engine deck lid screen, sort of like the square rubber air intake on the drivers side of the deck lid. The actual opening might be on the order of 3" X 6" or so. You might have a small hole in the bottom so rain and water would drain. You would get cool, outside air no matter what your speed regime was. After the oil thermostat opens, it's always cooler outside the engine compartment than inside it. You would definitley be changing your air filter much more frequently though. Seems like it might be pretty easy to fab up out of thin plstic or aluminum to start with ...maybe we can get a rubber or plastic molding company to make them. Or maybe not..

AOW162435

Marlon,
There is an intake 'trumpet' available through Porsche, part number: 993.110.360.51. I think it's meant to mate with the underside of the RS tail - but you could always use it as a starting point for your idea:





Andreas

Pete Lech

Item # 13 is used on Turbos and AeroKit cars with a fixed tail.

My understanding is that for the moveable tail cars, the air flow hits the raised curtain and is reflected into the opening on the sports intake. If the tail is not extended, you do not have room for #13.

There is an intake temperature test on p-car.com at
http://p-car.com/diy/intake/

TargaTango

Marlon,

I had some similar thoughts. I now have a RS Cub Sport tail and thought it would be a great idea to fabricate ducting from the left side air intake to the engine air intake, but the following thread made me realise life is not so simple:

https://rennlist.com/forums/964-forum/277537-air-intake-temperatures-with-a-cup-drilled-airbox-versus-a-stock-airbox.html

Andreas,

Interestingly, I spoke with my mechanic about the RS intake trumpet. He had not seen any fitted to the 993 RS's which have come through his shop in Hong Kong. He promptly opened the lid on an RS with a Club Sport tail sitting nearby and sure enough it had no air scoop.

JasonAndreas

The intake trumpet was only used on the turbo models.

Wilder

Interesting indeed. A buddy and I were talking about such contraption this past weekend. It would look exactly like part 13 but sit flush with the grille.

The question is: what would be more effective in terms of feeding cold air into the intake, air reflecting off the spoiler wall or air funneled through the duct assuming that part #13 can be cut to sit flush with the grille?

Is there any way to test the efficiency?

Marlon

This is a no brainer, Sunset: "Hello, Phil - I need one 993.110.360.51 pls, yes, UPS Ground is fine, Thx..."

Peter R.

Didn't the nice bloke at p-car.com do a temperature measurement on intake air ?

Anyhoo, I use an open Fabspeed lid. I figure if there's any cold air around it's gonna get sucked in.

Peter R.

Marlon

Yes - he did. On average OAT is 10 deg. cooler than engine bay air. Guestimate is 1% power increase for each 1% inlet temp decrease. 10 degrees = 10% - that my friends, is tangible power to the rear end. For 55 bucks?!?!?

NP993

So based on your math, if I dyno my car on a 70-degree day and it puts out stock horsepower, on a 60-degree day it'll put out 310 horsepower? Do you have one of those internal BS meters? They look like this:

jimbo3

P-Car says change of 10 degrees F in temp = 1% change in HP (2.8 BHP). Realistically, 5 degrees is probably the typical improvement your going to have in intake temp in a NA 993, so it's worth about 1.4 HP. Doesn't seem like much, but there are a lot of folks who paid a lot more for HP mods and gotten less than that!

TargaTango

Suggest people read the link I posted above. Here it is again

http://forums.rennlist.com/rennforu...ad.php?t=277537

Marlon

This forum is full of armchair 'experts', handling dynamicists & Porsche reverse engineers, etc - what's a little more BS to further obfuscate the truth I'd rather have a few extra real HP to the rear end than the Mattel sound of Power any day...

jimbo3

To each, his own. Seems like alot of time and money for one theoretical HP, though. I'd rather !!

TheOtherEric

Lol, pot meet kettle, kettle meet pot.

As an FYI, my data logged testing at speed showed a couple hp loss with the RS snorkel versus the open (cup) airbox due to the added flow restriction. That appears to contradict your 'expert' conclusion.