Just put my IROC on the dyno for the first time today. I never thought I'd do it because it's just my beater car and I've never really had any intentions of doing anything with it (motor wise) so dynoing a pretty much stock 3rd gen just felt kinda silly.

But since one of the car clubs I'm in was having a get-together and we got a $50/2 dyno pulls deal at this perfomance shop, I figured why not. I'd dyno the car just for sh*ts and giggles.


Here are the details of the motor.

- 1988 L98 with 180,000km on the odometer

- SLP headers
- Dynomax cat-back
- Crane 1.6 RR
- A pair of factory replacment K&N filters


That's it and that's all.

All else is 100% stock. The runner's, plenum and intake base are all 100% stock. Heads and cam, all stock.

Basically, just an exhaust and rockers and the car made 212 hp and 290 lb of torque at the wheels .

I'm happy considering how little I've done to the car. I've got AS&M runners on the way and I'll be upgrading to a full 3" exhaust pretty soon (my current Dynomax is some strange size like 2 7/8 or something weird- not even a full 3" )

. I'm absolutely positive I'll put out in the area of 230-235hp and 310-315lb of torque at the wheels with those two extra mods alone. Can't wait. With an aftermarket intake base, and ported plenum, this car will really wake up. I'm guessing well over 250 at the wheels and in the area of 340 torque.

So what do you guy's think? 212/290 for 3 mods. Sounds good? I'd really like to hear what others have dyno'd with similar mods or what you guy's would reccomend I do next....

Here are a few pic's I snapped of my car. (excuse all the dirt, it rained all night long and I didn't have time to wash the car this morning )

 

sounds pretty good man..i got mine dyno'd today but i have a converter and didnt lock it up and so my numbers seem really low...and the dyno didnt read the run till near 4000rpms so my torque is LOW as well.

i had 200whp at 4200 and 261 tq at 4000, but i know i'm near 300 down at the 3000rpm range

i have just full exhaust as well and gutted air intake

 

not bad numbers for as little as you've done, dirt or not that's a sharp looking car. Sounds like you've still got some free mods to do as well. Bump the timing a couple degrees (or chip it) do the T/B coolant bypass and you'll get a bit more.

 

I was there witnessing this Dyno day as my car is still in the shop. Phil, LT1FUN, already has the TB bypass, don't know about the timing though. I have a vid of the dyno run, it's not the best quality but it's something you guys can watch. The day was awesome! So many nice cars...

I wanted mine so badly

 

could you post the dyno chart graph please, i want to compare it to mine. mine started recording at like 3800rpms so i just wanna see how your tq at that rpm compares to mine

 

looks nice LT1, once my runners get in i going to dyno mine aswell.
cant wait to get those runners

what are your track times?

 

Thanks Steve for posting the video. I've got to go out and buy a Firewire cable to hook up my DV camcorrder to my PC so i can uplad the video's I took for everyone to see.

When that dude was dynoing my car, I swear I thought he was going to blow the motor. He wouldn't take his damn foot off the gas!!! He just kept going and going and going, I felt like saying sh*t dude, the cars TPI, WTF are you trying to do

He was reving the thing to the freakin' moon. He must have thought he was still in that Vtec car and tried to spin the motor to 9000rpm, I swear.

Yeah, I do have the throttle body coolant bypass but I don't think that would have made much of a difference.

What is surprising (and what's got me thinking) is that on the second run, I picked up 6 HP at the wheels just by removing the two K&N filters. That's a lot of HP.

I'm really starting to wonder how much the stock plastic intake plenum is costing me. I'm considering making up some sort of cold-air induction set-up using 3-4" pipeing and one of those big conical air filters. I'd probably pick up quite a bit.....

 

did you gut the stock airbox? i'm surprised that the filters held back that much power.

gives me an idea next time i'm at the track. i almost took them out but it was about to rain so i just left them in and went home. i wasnt gonna get that last run in

 

Yeah, that was one of the first things I did. I cut out the baffles before I put in the K&N's. I was surprised too when I picked up 6 at the wheels by removing the filters. I'm guessing it has more to do with the air plenum itself than the filters. I mean, they're K&N's so it's not as if they should be that much of a restriction, especially on a car under 300hp.

I was looking at the air box today and it's actually very restrive when you look at it from the side. At one point it's crushed down to about 1"
That cant be good for airflow...

 

Should make a system similar to mine dude, cost me $2 bucks, lol! I'll be making another one once I get the car back and using my front fog light hole as a ram air duct. Should work nicely, and hopefully I pick up the same if not more power than you got with just your air filters removed.

 

Sounds good LT1. Makes me feel good about getting home and putting on the Hooker 2055s, high flow CAT, Hooker CAT back and of course the AS&M runners. My IROC has 165k on it. Id like to dyno it b4 and after the mods. Hopefully Ill be home in the next month to get it all done.

 

Yeah, imagine what this stock L98 would do with a bigger exhaust system and ported plenum/AS&M runners. I wonder what I'd dyno?

 

I would venture that your well over 300 hp w/ what you have done.