Just curious if anyone knows how restrictive it is on a speed-density car with a mild 355 (HSR, mildly ported 180cc protoplines, comp cams 224 @ .050) My air box is gutted below the filters. I just wanna know if its worth my time to build a custom CAI, or if its only worth a couple of hps if I should just stick with what I have. I looks pretty restictive IMO

 

Sorry the car is a 91 z28, TPI airbox

 

You know, I don't think anyone makes an aftermarket replacement for it. That might tell you something right there. Or it could just be there's no way to build one that flows any better and still fits under the stock hood. Getting rid of the stock system of baffles below the filters (and maybe hooking them up ram-air style with some home duct work) seems to be the big upgrade.

 

I've read somewhere that, even though that looks REALLY restrictive.. it's actually not at all, and it flows more air than the throttlebody can handle, i think

I think, anyways. I don't remember the details. But it's not as restrictive as it looks

 

hmmm...but what about a 58mm throttle body? Doesn't the factory TB flow around 670 cfm? and a 58mm around 1000 cfm? I hope its not as restrictive as it looks, I dont want to relocate my battery for a homemade CAI...

 

The dual snorkle on the TPI flows around 700 cfm.

 

that airbox is very restrictive, swappin from stock TB to 58mm with stock airbox, you will hardly see a difference....i don't think it even flows 700cfm like what a previous post said..i heard more like 500-600 CFM...that is pathetic....K&N makes a filter for the TB, but it sucks warm engine air, but I would say yes its worth makin your own custom air intake system....big upgrade over stock...

 

gerry-rig a cheap cai out of some dryer hose and see what the difference is at the track or SOTP

it may be more than you think

 

will a modified one fit under the hood, my 87 has little clearance between the airlid and the hood....

 

Thanks for the replys. I think I'm gonna try rigging something temporary and see what kind of gains I get. If I get a chance, I might even go to the dyno and do back to back with the airbox, and then open TB. If I get to the dyno, I'll post the results for future reference.

 

Really??!? That's kinda wild, because I did the same thing on my T/A (made a CAI from rigid 3" tube & a K&N, removed MAF screens, & ported the upper plenum), & about the only difference I noticed was that the engine would rev more freely... (Do you happen to have the month & year that was in? Was it the "Blue Thunder" car?)

I really didn't notice any SOTP difference, & I would think that 20-40 hp would be fairly noticeable...

(Hopefully my next round of mods - heads, cam & intake - will give me some more noticeable gains...)

 

slp sells one, but you have to relocate the battery and the fuel canister. i was going to use 3" exhaust tubing and have it follow the stock routing both with obviously bigger tubes. then it was going to go through the grille with 2 3" cone filters. but then i got lazy and never did it. i also had the hood clearance cause i had a 3" cowl