918 install???
09-09-2009, 07:10 PM
#1
918 install??? Am adding 918 springs to the LS1,[2001] heads on the LQ4. [2005].
I found the "2 piece" stem seals on the 01 heads. [Seal, and the spring seat are seperate.] The new seals are 1 pc w/ the spring locator on the seal.
The 918 base ID is bigger than the original LS1 spring, and is "sloppy" on the locator.If I use the 1 pc seal deal, the "slop" on the locator gets worse. Spring ID is .882. The original locator is .850, but the new seal/locator is only .788. I'm thinking these are out....
The cam is at .581 lift, leaving approx .115 clear B4 coil bind. If I use the CC locators,[Pt# 4705], they are .060 thick, vs .020 on the stamped locators now on the heads.
Using the CC locators is obviously going to shorten the coil bind to about .075..OK/No??
What's the "norm" for installing the 918's?
Also, I found no chain tensioner on the ft of the engine. [Chain seems loose to me]. This engine has only 15K on it, and had not been apart, prior to my acquiring it.
Should there be a tensioner? SD parts indicates there's 1 available, and is listed for 2005 and newer engines.
I see alot of discussion on chains. NE1 have a particular favorite?
[The car, [55 Chevy], is not a racer, but may get a 1/4 run, on occasion.]
NE advice is appreciated!
I found the "2 piece" stem seals on the 01 heads. [Seal, and the spring seat are seperate.] The new seals are 1 pc w/ the spring locator on the seal.
The 918 base ID is bigger than the original LS1 spring, and is "sloppy" on the locator.If I use the 1 pc seal deal, the "slop" on the locator gets worse. Spring ID is .882. The original locator is .850, but the new seal/locator is only .788. I'm thinking these are out....
The cam is at .581 lift, leaving approx .115 clear B4 coil bind. If I use the CC locators,[Pt# 4705], they are .060 thick, vs .020 on the stamped locators now on the heads.
Using the CC locators is obviously going to shorten the coil bind to about .075..OK/No??
What's the "norm" for installing the 918's?
Also, I found no chain tensioner on the ft of the engine. [Chain seems loose to me]. This engine has only 15K on it, and had not been apart, prior to my acquiring it.
Should there be a tensioner? SD parts indicates there's 1 available, and is listed for 2005 and newer engines.
I see alot of discussion on chains. NE1 have a particular favorite?
[The car, [55 Chevy], is not a racer, but may get a 1/4 run, on occasion.]
NE advice is appreciated!
09-09-2009, 08:16 PM
#2
Chuck,
I put 918's in my heads using the stock locator/seal combo. Didn't notice any slop in the fit...
I used a Rollmaster double chain and ported stock LS-6 pump. That combination did require clearancing the cover. My engine ('03 Corvette) didn't have the tensioner and the block was not drilled for it. The Rollmaster chain is tight! We'll see how it plays out next teardown...
Russ
I put 918's in my heads using the stock locator/seal combo. Didn't notice any slop in the fit...
I used a Rollmaster double chain and ported stock LS-6 pump. That combination did require clearancing the cover. My engine ('03 Corvette) didn't have the tensioner and the block was not drilled for it. The Rollmaster chain is tight! We'll see how it plays out next teardown...
Russ
Thanks, all. 
