This is in regards to my '89 IROC.

I recently finished up an engine rebuild on my L98 in my IROC. It's the original engine, and I rebuilt it with the same heads and stock (new) cam. The only "improvements" over stock are the double-roller timing chain, hyperkineutic pistons, chrome-moly rings, and Clevite 77 bearings. The heads were rebuilt, but no modifications made (except for new valves where needed). Obviously, my plan was not to build a hot-rod or anything that's going to achieve a certain 1/4 mile time--I just was looking for the kind of "fast" that this thing had off of the showroom floor. But, I never got to drive this car before the rebuild, so I don't really have anything to compare it to.

It just doesn't seem quite as powerful as I would have thought. I know people say that the L98 has a lot of "tire burning" torque--but I stepped on the gas today from a stop and I didn't even break the tires loose. Also, if I'm on the highway going 55MPH and I want to pass somebody, I'll get it to downshift into third and just gradually pull past. Mabye I was being unrealistic, but I would expect that it would feel a little more "agressive" (not that I want to be an aggressive driver--but just to know that it will push me back in my seat every now and then). Is this just because I'm running a 2.77 rearend, or is something wrong?

Also, I'm wondering, theoretically, shouldn't I be making close to the power that this car would have had off of the showroom floor?

I know this is somewhat vague and tough to communicate just by "seat-of-the-pants" feeling--but I just thought I'd ask to see if anybody can agree/disagree. It would be nice if I could get this thing dynoed, but I don't know who can do that...

Thanks

 

TPI's are not known for their top end power, though from 55mph you should still have plenty of power left. If you have good tires, you shouldn't be able to smoke them by just flooring it, though I can, and I blame it on bad suspension.

I have plenty of go from 55mph, enough to overtake most cars before they know I'm coming, but after 100mph L98's don't do so well. Part of it is because you can't shift into OD at WOT. That issue can be fixed though.

Actually, I can't go anywhere right now, my engine and my tranny had a dissagreement, and the tranny lost. ^_^ Thats ok, I got a new room mate for the engine already in the garage. Just waiting for a good time to drop it in.

 

What size tires do you have?

 

They would be BFG G-force KDWS 245/50/16's, not the best tire by anymeans but they are a good tire.

While my car has some "mods" if you could call them that, its not something that would provide even a 10 or 15hp gain.

3" catback, and 1.6 rollers that I got for free with the reman. Like I said, maybe 10hp gain if I'm lucky.

 

I would say something went wrong during the rebuild. Even though it was just a stock rebuild, you should be able to leave a little bit of rubber by punching it from a stop, even though the L98 had like 325ft/lbs or something, they should be able to do that. Maybe he assembled your bottom end tight or something...

 

Yeah, I thought that it was supposed to be relatively easy to light-up the tires on this car. They will both spin if I torque-brake, but that's about it. Even stock, the 300+ ft/lbs of torque come low enough that I think I should be able to spin them without going WOT.

RE: the tires-- They're brand-new Yokahoma YK420s all the way around. P245/50R16.