Headers, bolt-ons , and maybe a cam for my bird. It's got 109,xxx on it. It has a little knock when I first start it and the temp is freezing cold. She still pulls strong and runs fine. Go for putting the parts on?

 

Absolutely! The knock on startup is most likely the well known LT-1 piston slap issue; It's very common.

My car has 119K miles on it, and I have to issues reving it up to 6k with the mods in my sig (headers are going on next)

If you take care of it ... (change oil, replace air filter, etc...) and resolve issues as soon as they arise, it'll be fine with headers and bolt ons (as long as you don't consider NoS a bolt on )

Thomas.

 

never herd of the well known lt1 piston slap. ls1 yes but not lt1.

say do the headers and bolt ons, but i would hold off on the cam till you figure out why its knocking.
if its a slight tick, it might just be the injectors.

 

Huh, I'm surprised you haven't heard of this with an LT-1.

Mine has always done it (even when it had 70k miles), my buddies '97 SS also does it, and my Brother's '97 Z did it too. It's a rapping sound above 2k rpm or so, from the motor when it's cold. I just keep the RPMs below 2k for the 1st 10 miles or so in the morning.

Thomas.

 

nope never have herd that.

i know the stock throw out bearings will make a rattling noise.

 

Ummm my blazer knock's when it's cold' it's not piston slap it's rod knock...

 

Personally, I would do the headers and other bolt-ons, but hold off on the cam.

 

Agreed

 

I don't think a cam at 109k miles will be a problem, as long as it's installed properly and the supporting hardware is replaced with quality stuff (lifters, pushrods, springs, etc ...) ... and as long as you don't plan on spinning a stock 109k miles bottom end to 7k RPMs

But, I haven't done a cam in a high mileage LT1 before, and there are reports of cam bearing failures after a cam swap on a high mileage LT1.

If you really want to make an informed decision, do a search for "cam bearing failure" and see what you find.....

Thomas.

 

Thanks a bunch guys.

 

sure

 

<---- Has never heard of LT1 piston slap either.

 

that knock when its cold is most likly the lifters has trouble geting the cold oil into the lifters

 

my first 93 did it only in the winter when it was ice cold...it was a slight tap. I sprayed 150 shot on that engine at 130k miles..almost 2 bottle a week..and i prolly went through 30 bottles of 100 shot..never had an issue with the engine.

 

Lifter's tap, rod's knock, exhaust tick's..