Okay, check it out. I opened my airbox lid and have a K&N filter. I ported my MAF removing the metal in the way (also polished metal housings) and removed plastic stud from sides of actual sensor. Kept the screeen on. Now I'm installing pacesetter headers (shorty headers) painted with thermal sleeves.

estimates I have read say that a MAF P&P and opened air lid with k&N filter can give 20rwhp. I have heard the headers can give around 20-25rwhp. Would it be out of the question to say I could have 350hp at the crank when it's all said and done? Also, would using a TB airfoil give anything? Jegs says that they give 11rwhp. My goal is 350-360 solid hp at the crank.


1994 corvette coupe


[Modified by sstcorvette, 7:25 AM 10/31/2003]

 

Well.....

The more your engine needs the extra air to make HP the more benefits you'll gain from the cut lid and the K&N. But it's a good place to start but don't expect anything spectacular.

Shorties headers will give you some if they are equal length tubes. If not, you might as well stick with what you have. You already have tubing manifolds, just not equal length tubes. Longtube headers would probably give you 20HP but I'm not sure about shorties.

A good investment would be the Desktop Dyno 2000. It will tell you about what you can expect from certain mods. Mine said my cam gave me an extra 50HP and I believe it. The cam in C4's are pretty whimpy.

Think of the engine as an air pump. The more air you can get into and out of the motor, the more HP you're going to make. But all the air in the world won't do anything unless the valves stay open long enough and open far enough to get the air to the cylinders. This is where you should make you first major mod, IMO. Once you have the cam, then you can start porting things and/or replace them with good aftermarket pieces like maybe a Mini-Ram, larger runners and a 52mm throttle body. Then the HP starts climbing quickly. Headwork makes BIG jumps in HP.

BTW, the airfoil is pretty much a gimmck. Don't waste your money.

Hope this helps,

BIG JIM

 

I'll take a stab at this, the caveat being that its from what I've gathered here at the CF since joining last summer. Your mods as you state them might get you about 20-25 chp, not rwhp. Subtract approx. 15% (manual) to 18% (auto) to account for accessory/drivetrain loss:

MAF: 5chp
K&N/open lid: about 5chp, maybe a couple more
Shorty headers: about 10chp

LT headers are superior to shorties.

You didn't mention anything about the rest of your exhaust. The L98 responds well to a full-out exhaust upgrade, not entirely sure about LT1. But I think its pretty safe to say you should also look into this part also.

I'm still fairly early in the learning curve, so you may take what I've said with a grain of salt. The real pros no doubt will chime in and provide real world info, with dynoed rsults. There are alot of guys here who are outstanding, you joined the right place to get to the bottom of whatever you might encounter. Good luck! :seeya

 

Here's my estimate:

Shorty headers = 5 hp
K&N + cut lid = 5 hp
MAF porting = 1 hp
TB airfoil = 0 hp

Those magazine numbers are pure BS. You're looking at 270 rwhp. Why do you care about crank HP? That's meaningless in my book.

 

Here is something for you to consider. I have an LT4 with Hot Cam, corsa exhaust, SLP claw intake system, throttle body coolant bypass. I made only 316 hp and 306 torque on dynajet dyno.

This weekend I have bolted on tpis Long tube headers and hi flow cats. I should be able to get numbers next week. The guys that run the garage also have LT4's (as well as C5's). They realized a 10% increase in torque and HP with their header installations. Forget the dime store numbers printed in promotional ads. If you want HP and Torque you have to open her up so she can breathe!

 

That kinda sux. I was hoping 330hp at the crank. I'm trying to get it up to LT4 stock hp without cam, roller rockers, or head porting. I'm lazy and want to squeeze what I can out of this car before I sell it.

 

makes NO sense...

 

Sure it does. I want to do fairly easy uninvolved modifications(no cam install, no head work, etc) but get gains up to my goal so when I sell it, it will be easier to sell (with slightly higher output, and hardly any work on my part). Around here it will sell better if it is a little *hot*. I just don't want to put lots of effort into it.

 

Install a set of cut-back AC Delco plugs (details on my site, see sig. below) and do a 160 deg stat & chip. These should be worth about 15chp.

You might get 10chp from the cut lid with K&N; do a good cat-back along with the shortie headers for a little more push.

And don't foreget the AFPR to add a little more fuel to that increased air flow.

 

I disagree. This never holds true. Perhaps, if you spend $1000 on it, it may be worth $500 more, but it is never worth it, especially when you include time and labor.

If you want to do easy stuff to raise it's selling price, detail it inside and out. Fix small interior things that are broken/non functional. Fix minor leaks, and change the noticeable fluids (brake fluid, motor oil).