rock582

I have a 85 Iroc with a 87 L98 out of a vette, we pulled the motor thats why I'm sure. Its bone stock

Dad has a 99 GTP with the 3.4 setup with all supporting mods.

He said I'd kill him off the line but he thinks he would comeback around me.

What do you guys think?

midias

What trans / rear do you have what are supporting mods?

budfreak1

iTrader: (7)

He'll end up with the win on this one. What are you running for a ECM in the IROC?

T/Atime

should be a couple of 14second cars going at it.

i think the iroc will get the upper hand, providing its running tip top. i would do a small burn out to clean up the tires first then let em have it!

from factory are those gtp's 15second cars?

T/Atime

i guess these guys have raced by now its been a few days. whats the results?

budfreak1

iTrader: (7)

From what I've read and seen, the mods he is describing for the GTP would probably put it in the 13's (14 sec. car from factory). If he's not running the 87 vettes ECM, then it's not running right because the 305 TPI ECU in his IROC will not run the motor right at all. In all reality, due to some wiring differences I think he would need his stock ECM with a custom tune from somewhere like pcmforless if he didn't use the wiring and ECM from the vette.

T/Atime

wow, those gtp's have some go! now i wanna race one, lol.
budfreak, nice car btw. i like the direction your car is taken. how do you like the quality of the hood, looks sharp!

rock582

Thanks for the responses.

Yes i do have the ecm from vette we bought the whole car for 700 bucks.

I have 3.42 rear out of a 4th gen.

His suppporting mods are slp cai, down pipe, Ubend delete, ZZP pcm, colder plugs, 3.4 pulley. Probably more i cant think of them all.

Hes wanting to go with a 3.1 pulley after he does his intercooler but hes thinking he may need heads or head work to do it without knock.

Hes always scanning for knock

Well anyway we went about 10pm that supercharger loved the cool air that night.

3rd honk and yes i blasted him off the line. He slowly launched his car, hes scared of breaking tranny.

Bit it was all over with by 50 or maybe a little more, he was around me and pulling. we shut down then.

No need in abusing engine when the point is proven

UnderCover89TBI

iTrader: (25)

got smoked! haha. j/k sounds fun althought I do not condone street racing but it sounds to me like you guys had it under control

rock582

Yeah no need to go to any insane speeds when the point is done. Lol hes faster. This actually his acct. He was using to find my car, and do some research lurking around. I need to get some pics up.

He wants te get me as quick as him at the track, depending on track and weather hes run 8.6 to high 8 till he broke his first tranny.

Oh thats in the 1/8 mile of course.

Thirdgen89GTA

iTrader: (5)

Pretty much what I expected to happen. Anytime you do a pulley with a supercharged GTP its gonna go alot faster.

BigWhiteGTP

Yeah, pullied GTPs are no joke for a TPI car. Mine was low 13's high 12's@105 with the following mods: 3.25 pulley, fenderwell intake, 1.9 rockers, ported exhaust manifolds, 3" downpipe, cutout, and a custom mail order tune. This was back in 2004 before I crashed it.

I wanted to do a 2.9 pulley, TOG headers, and an alky injection with a new tune.

A stock GTP puts down 190-200whp and 270wtq. With just a pulley/intake/ubend removed, they put down around 230whp/310wtq.

Thirdgen89GTA

iTrader: (5)

The 3.9L n/a's on the G6's are pretty good too, but nowhere near as easy to add more power unlike a S/C GTP. the NHRA calcs based on my Trap speed say the car is making between 240-250hp at the crank, and with the 6spd thats probably a 15% loss for about 210whp. Its a heavy car, pretty much the same weight as my GTA.

budfreak1

iTrader: (7)

Thank you. The hood is very nice. It could fit a little bit better, but I think that can be remedied and I just can't figure out how (I'm not a body man and I've made all the adjustments and changes I can figure out to make).

rock582

Would the stock heads breath with headers and a new tune and maybe rockers at a 3.1 pulley without knock? I was going to intercool it but if i can get by without it. Friend of mine blew his up, never scanning for knock. He threw on a 3.4 pulley and let it go at that.

Thirdgen89GTA

iTrader: (5)

You need to keep it cool first and foremost. You can run the 3.1 pulley just fine as long as you have a good tune. Detonation is your enemy. You can also look into an alky injection kit.

You will have trans problems eventually though.

rock582

Yeah as my son said earlier I've already broken one. Thats why I won't full bore launch the thing anymore, its also my daily driver. My wife drives a 07 gxp, thought that would be fun but almost no aftermarket for it. My GTP would bust its ***.

What would be the best banf for the buck for my son exhaust? I know the TPI isn't a great breather but i have seen fast TPI's before.

Thirdgen89GTA

iTrader: (5)

The Vette L98?

There are many things you can do. I'm a big proponent of a HSR swap. Simply because of the huge power gains. The peak power gain is small, but the extra 1000rpm of power you get above 4500rpm really wake the car up and make it more fun to drive. But I have an LT1 and I love its powerband. I really don't notice the missing torque. Sure, its gone on paper but I hardly notice it because of the way an LT1 likes to rev. Even with a small cam an LT1 will pull hard to 6k, HSR's are the same way. And with the right cam and heads they'll pull even higher.

skiroulertx447

I raced a coworker in his gtp with my Z28, both cars had mild mods on them, they were side by side, but whenever mine shifted it would pull away a little.

BigWhiteGTP

Get right out of town!! Can you tell that story again? Kidding. A good running L98 with the right mods will still hang with a mildly modded GTP. But in terms of $/hp the GTP starts shining very quickly.

skiroulertx447

we raced a couple times on some roads in mexico and he claimed i jumped on him, but it was pretty close, the l98 pulled a little better though, especially at lower rpm after shifting.


My "l98" isn't an l98 though, 350 block from 1968 with 487 heads and unkown cam right now...