Ok guys and gals. Got a few questions. My formula has alot of highway miles on it....there highway..but still alot of miles. Dont know the exact figure off the top my head but its right around 135000. I was thinking of putting a set of SLP runners and a set of headers on as well...but ive heard from several people that with a motor with that many miles on it would up the chance of me burning something out. A few people said that if i wanted better off the line acceleration.....to get my gears changed out. Right now i believe im running the 273s. Does anyone have any info on this or any other suggestions. Im trying to get as much off the line acceleration as i can without spending a reall lot...but not going cheapo with things either. Thanks

 

I don't see why there would be a problem, those mods are "good" for an engine.

 

The odometer rolled over to 143,600 when I pulled the Camaro into the garage to do my mods in Nov '01.

Reads right around 154k now.

 

If the car is properly taken care of, 135k isn't alot of miles.

Get the headers. Do gears, but no more than 3.42s. And forget those runners. Without substantial mods to the rest of your car, they will do absolutely nothing for it. They are not a single-item bolt-on kind of thing like an ignition coil or something; whatever good they do is as part of a system. Spend your money on something that will get results.

 

As long as you don't do something to goof with the compression you should be OK. I wouldn't go changing heads without a rebuild though.

 

3 years ago i rebuilt the engine in my 1st Trans-Am, with 217,000 miles, it still had the cross hatch in the cylinders and good compression befor the rebuild. my current T/A has 208,000 and good compression and would not think anything of to put headers or any other bolt on, besides if the engine dies you still have the goodies to put a new one if needed. just my 2 cents.

 

Why not? It can ONLY help things to have properly functioning cylinder heads.

 

Anything you can do to improve the breathing ability of an engine can only help it. Start by "uncorking" the exhaust, i.e. Headers, 3" cat back system & high flow Cat. Then work on getting more air into the engine. The easier it breathes the better it is for the engine and it'll more power, easier.

 

I just know from experience of friends that new heads on a worn bottom end will cause the bearings to fail. I believe it has to do with increasing compression. It is only like that on an old bottom end though.

 

The thing that usually kills bottom ends when you put new heads on them, isn't the heads themselves, or the compression, or anything else mechanical.... it's usually the enthusiastic test-driving that always seems to follow the swap. If the owner doesn't start abusing the car, there's no problem.

 

Then why swap haeds if you can't have fun with your car?

 

I think RB meant ABUSE, more so than enthusiastic. Even a brand new engine won't last long if all you do is put the pedal to the metal.

New heads will help any shortblock that isn't already toast.

 

Still with that many miles I wouldn't put new heads on the motor unless they are the exact heads that it had on it before.

 

I would.

Oh, that's right, I did...

 

LOL

Anyway... i think what some of you are trying to get at by saying that you should not add new heads to an un-rebuilt motor is that it would be a bad idea because it would introduce unfamiliar stresses to the aging and probably worn out parts, which could have catastrophic results. I'm really not sure which side to take, because i've heard good arguements for both sides, but mainly it depends on the condition of the motor, and the owners driving style i guess.

 

Well I'm gonna find out, adding new heads and cam to an L98 with over 200k. If it does fail, which I doubt it will(I have faith in my old iron) a ZZ4 shortblock is just a few $$$$ away