Actually the factory intake is not that bad. I see many gripes about the "restrictive” intake.
I have looked over my 91, and assuming you have a good air cleaner, the two main restrictions are the AFM (which most of us are stuck with) and the HOOD PROP.

I have yet to see a post about the hood prop.
It stows DIRECTLY IN the intake path.
I removed the stock prop.
To hold the hood up I use an aluminum tube.
It stows in the groove behind the snorkel on the fan shroud.

It has been the first mod done on my last two 7's.

 

Wow... that's... creative. I would never have thought of that.
Any weight savings with that? (hehe) I jest.
Any noticable increase in response/power?

 

It saves maybe a pound.

It big deal is the stock prop blocks about 20% of the stock intake path.
It's easy to overlook when the hood is up.

 

I understand that... but does it give you any seat-of-the-pants power?

 

THis has to be some of the dumbest **** i have ever heard.

-Chris

 

no its not, it really does make sense coause when the hood is down there is no wher for the air to go except right past the prop.

 

I guess you could use a manometer or a magnahelic gauge to prove your theory. However, I would try to prove it. Placing the hose behind the area in question.

James

 

it is interesting, but how much of a difference does it really make? If it really was blocking 20% of the intake it should make a feelable... is that a word.... difference.

 

Steps for getting more power.... via intake design

1. remove washer bottle assembly. Enlarge stock 1.5" hole to 3"
2. Buy a conical filter and adapter (s5 guys dont need adapter)
3. Build cold air box
4. Remove passenger side brake duck
5. Run a high quailty 3" tube from passenger brake duct inlet on bumper to your new cold air box.

Simple. Effective. Cheap power.

-Markus

 

If you really want to get technical Remove the coolant from flowing around your TB. This really..really helps. You may have some problems in colder area's IE: (Northern regions of america) When you first start you car in the morning (you'll have to help it idle to warm up)

Again. Simple. effective. Cheap power

-Markus

 

you can always get an early 86 coolant overflow bottle. (like my car) and it installs directly behind the leading coil on the fender wall.

 

really?
I just may have to do that!!!

 

Just some info on the factory system from my experience:
Must agree that the factory intake system can't be that restrictive. I've cut holes the box, cut the top out of the box, and experienced virtually no change in boost or performance. '89TII Bonez DP, Bonez Hi Flow cat, original factory Y pipe and muffers. The car runs @ 7/7.5 lbs which is to be expected. Installed a reprogrammed ecu and out of the box it topped @ 11 lbs. If the factory intake system was that restrictive, I could have never pulled 11. The car has cold air via the factory system, emissions legal (cat and air pump), fairly quiet, and the boost right where I want it.

 

you know i could see if you said something like removeing something thats directley in the intake path(secondary throttle plates), or if you said something like honeing out the intake. but the hood prop?

-D

 

I salute your effort and question your math. 20%, NFW!

 

in all honesty i dont think the prop rod does much, because the intake isnt really functioning like a ram air system, using just intake vacuum, its gonna pull air from whatever direction it can, around the rod, i could be wrong and you may pick up 30 whp but thats my humble opinion

 

How did you do your calculations, that the little tiny 7/16-1/2" diameter hood prop is blocking 20% of your intake?

Ohh ****

you know your hood is block 11876% of your air flow

 

this is ridiculous. I've heard that many S4 owners are cheap...but come on!

 

Amen to that!

But we're not cheap, we're just broke!

 

What is it blocking? The air would flow around it anyway.

 

I must agree that the hood prop would block nothing, the air would go around it with ease, and like someone said its not a ram air setup so its using vacuum to suck air in. This means that the air is just gonna get sucked all around the prop.

If you want a really good cold air intake setup then cut a hole in the sheet metal beside the Rad and re-route the intake into there. My buddy had that setup for his TII and this winter after a nice highway jont if you pulled over and felt the intake it was all stone cold and there was almost frost forming on the filter. Works like a charm.

later
-Justin

 

i feel dumber for even reading all this...This definatley takes the cake>

OH BOY

 

 

I just logged back on & it looks like some people need a visual aid.
Pictures to come..

Until then the stock intake snorkle gets its cold air from the gap between the hood & the top of the radiator support brace.
That gap is 1-3/8" when the hood is down and the stock prop rod takes 5/16" of that.
Feel free to do the math.

 

It's hard to believe that you could represent all the S4 community, what with your $500 7GMTE engine, and all. There's a joke if I ever heard one.