dogfish246

That is true! They made the C4 so good from the factory that there is no need for an intake, exhaust, etc... I wonder what the surface area comparison is???

HONDOBUCK

It is in fact a C5 air cleaner system and my vette is an 86. I removed the upper air bafle as you can see in the picture and I run my car with out it. I took a rubber 3 inch hose clamp or what ever its called sause i cant remember right now and then I put it to the MAF sensor. The sensor is about 3 inch coming out so I just tightened the hose clamp on the boot down tight. Next I ran a pipe (in the pic its plastic) but I changed it to A metal pipe that was 3 inch that I bent in a vise so it would clear the hood and I put it in the other side of the boot and fastend it down. Then I used a 90 degree rubber pipe thing (whatever) and went of the end of the pipe with that. Then on the down end of the 90 I put the Air cleaner T and it works great. It catches so much air because its down infront of the air conditioning condenser and about 3 inches above the lower air baffle underneath. Sorry if its confussing but im trying my best I hope this helps you a little Cause it was pretty simple to do. But U will have 2 remove the upper air baffle or u can just cut a hole in it i guess but then it would be for waste if u ever changed your mind. Let me know how things went

93lt1fun

http://www.slponline.com/view_produc...50&BIG=21050-1

SLP used to make the same cold air intake (see link above and pics below) for the '92-'96 but, it appears they changed to the 3-cone setup and raised the price $130 from $199 to $329 for a less efficient unit in my opinion.
http://www.slponline.com/view_product.asp?P=21028v

I prefer the older version which I've had installed for 16 years. It mountes in the stock location using stock mounting poinst and it is truly getting cold air from under the front bumper where the radiator and A/C condenser get their cold air. The housing also and shields the incoming air within the housing as it goes into the enginer compartment and TB. The 3 cone version and others, including home cut-out versions have their filter element exposed to the engine heat so there is no way they provide as cold an charge or ram air effect older SLP unit.

I also have seen the bumper intake versions and they appear to be good also.

I can't say how much my SLP cold-air intake helps but, based on the track times in my signature I think it's working OK!

PLRX

I use the Vortex Ram Air on both Vettes. It sucks the air from the outside/radiator shroud.

aboatguy

Have you datalogged your car???? If you have does it show a positive pressure at speed?


Mike

LT4BUD

For my 1996 Corvette the K&N filter is 33-2035
Part 33-2035 Product Specifications
Product Style: Panel Air Filter
Height: 1.063 in (27 mm)
Outside Length: 17.563 in (446 mm)
Outside Width: 10.625 in (270 mm)Filter Material: Cotton Gauze
Filter Re-Oiling Amount: 2.84 oz (84 ml)
Weight: 2.1 lb (1 kg)
Product Box Length: 11.06 in (281 mm)
Product Box Width: 1.88 in (48 mm)
Product Box Height: 17.81 in (452 mm)

For a 1997 Corvette the K&N filter is 33-2111
Part 33-2111 Product Specifications
Product Style: Panel Air Filter
Height: 1.125 in (29 mm)
Outside Length: 16.063 in (408 mm)
Outside Width: 8 in (203 mm)Filter Material: Cotton Gauze
Filter Re-Oiling Amount: 1.82 oz (54 ml)
Weight: 1.8 lb (0.8 kg)
Product Box Length: 8.31 in (211 mm)
Product Box Width: 1.75 in (44 mm)
Product Box Height: 17.19 in (437 mm)

Area of 1996 C4 is 17.563*10.625=186.6 square inches
Area of 1997 C5 is 16.063*8=128.5 square inches

186.8 divided by 128.5 equals 1.452

So the c4 air filter cross section is 45.2% greater than the C5 air filter cross section.....

dogfish246

Nice! You would think that the C5 would have more surface area...

SloRvette

The '90 up air filter assembly was designed for the ZR1's. My '85 has the Forced Air set up and there's no ram air effect with it. I actually think the filter is too small (there's a restriction indicated by the MAP values). Putting a '90 up radiator support and air filter housing is on my list of things to do.

LT4BUD

The real question is where is the restriction......air cleaner, housing/plumbing, throttle body, MAF.....

Back to the OP's question, I think MAP readings have been overlooked by just about everyone as a key indicator if you are getting maximum performance from the engine..

The OP was looking for a positive pressure from a ram effect, but just maintaining pressure with increasing rpm is the first step...

The few MAP loggings I have seen posted ALL droop with increasing RPM..

PLRX

No, never done it

SloRvette

The restriction is either the filter or the housing. The car trapped 129 and change with a 92 kpa value thru the lights on a day where key on / engine off map value was 103 kpa. No maf, 1650 cfm throttle body. Taking the forced air cover off and running a cut lid didn't make a difference. Air cleaner to TB duct is a sheet metal aluminum piece that won't collapse.

aboatguy

I concur with all three of your observations...

I'm just perplexed why no one has actually posted 0 pressure loss or postive pressure datalogs over the years....which is the reason for my post.

I have a feeling that the ram air intakes don't actually provide ram air ...if they did the manufacturers would have posted the logs. Usually the answer is you can't see the ram air affect on a dyno (true statement) however, you can see the ram air affect at speed and datalogging is so SIMPLE an old Boatguy can do it.


So back to the question does anyone have a datalog showing positive pressure.......or no pressure drop at speed?????



Mike

Aardwolf

I would be happy to test mine once the engine is back installed. I'm pretty new to tuning though, what do I look for? Mine is an '88 for reference, and I have a front license plate scoop. I have a laptop and intend to try tuning, so I downloaded TunerPro RT.

CAJUN C4

My 95' came with one of these. Really a nice Intake.

aboatguy

See the 30.52 HG on top of data log and the map 30.41? That is the calibration difference of my two sensors with engine off...so if at speed my map stayed within .11 of the baro I'd know that there was no pressure drop...



Anyway on this 6900+ rpm screen shot (same datalog) I'm showing a pressure drop of about 2"




I don't know if the older C4s can datalog this info however, the later ones can so if there was a true ram air intake one would think that the manufacturers would have posted proof...







Mike

Aardwolf

Got no map, sorry.

rickneworleansla

I've done tons of data logs but never bothered to compare it to the stock setup. Here's mine below. Too bad they dont make these anymore.

LT4BUD

[QUOTE=rickreeves1;1574090155]I've done tons of data logs but never bothered to compare it to the stock setup. QUOTE]

I don't think the OP needs a comparison to stock, the question is does anyone have a ram input where MAP actually increases with speed....you could do this at the track comparing say 6000 rpm in first gear to 6000 rpm in 4th gear...or similar where the main variable is speed..

aboatguy

[QUOTE=LT4BUD;1574090386]Correct!


Or MAP readings at speed with a low pressure differential from BARO reading (IE no loss).


Rick what does your MAP reading look like at on a high speed run?

rickneworleansla

That shouldnt be a problem. I should probably clean the filter first its been a while. So exactly what data should I get? Speed?, rpm?, gear?, cruise?, WOT?, etc..


Here's the only one I could find on my computer right now. This was when I was working out the bugs after my cam install. This may even be one where I still had a leak at the back of my intake, not sure. 65mph isnt much help. I'll try and get some new data.