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Old 09-18-2010   #37
Pete
 
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Join Date: Dec 2003
Location: Chicagoland,IL
Posts: 2,667
Default Re: An enigma insues...

Tyler, i don't think there is a differance in the lifters.
There is a differance in valve lengths.
http://www.zr1netregistry.com/ZR1_specs.htm#9

Yes,your are right about leak down this is why i say she is a finicky girl there is alot of things one needs to know/check.
Once you crank her a bunch or run her for a few minutes lifters will bleed down.

What stinks is if one screws up it can cost some real $$$$ which will make taking it to a tuner in the first place a bargain.


Pete




Quote:
Originally Posted by Tyler Townsley View Post
Couple of things that need mentioning here. 1. You can use 90-92 lifters in all years without modifications HOWEVER you cannot use 93-95 lifters in 90-92 without cutting the valve stem slightly. The later lifters are taller than the earlier lifters. So if you do a valve job on an early engine and replace the lifters with the later design you have just created a nightmare for yourself. 2. When you do the leakdown test time will effect the compression and leakdown. JL long ago told me a leakdown test on a LT-5 is a crapshoot because you can get one set of figures with an engine with lifters that have bled down and another set for one with pumped up lifters so they never depended on leakdown info on LT-5s.

Tyler
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