I'm planning on using a Comp 212-218, 488/495 on 112 centers in my friends 97 half ton. I'm hoping it'll have a somewhat noticeable idle without destroying all the bottom end. He does what a converter also though. I'm thinking I can use this cam with some .050 extra installed height keepers and have adequate seal clearance. My main question is what's the best spring to run with stock retainers, if possible. Comp say use 915's but I don't know if they'll work with stock retainers or not. Since the cam doesn't approach .600 lift, a less expensive spring with adequate tension would be nice especially if they'll work with the stock retainers. Any clues? I don't know the diameter or the installed spring height. As you might've guessed, I've never had the valve covers off one of these engines but I'd like to have all the correct parts when I do take them off.

 

The yellow LS6 springs are good to .57 lift, and are like $50 for a set from SDPC. They will work with stock retainers.

 

everyone will say just go with the 915's or the 918's so you dont have to machine anything and with the +.050 lock you can run more than .500 lift safely. That is what I will be running with a little bigger of a cam in my obs 99.

 

They will work with teh stock GEN 3 retainers, but the GEn 1/2 valves stems are of a different diameter than the GEn 3 valves.

You can use teh LS6 springs but should get the Beehive reatainers to run them. tehre is a GEN 1/2 and a GEN 3/4 retainer kit.

peace
Hog

 

Oh yeah I didn't see he was talking about a 97. Just assumed it was a GENIII. My bad.

 

Along with what everyone else is saying, you may can use LS6 springs and maybe not be able to, due to interference between the O.D. of the guide and I.D of the spring, as the tolerance is so close, coupled with slight variations in machining tolerances of the factory heads. The Comps have a slightly bigger I.D., which will fit with ease.

 

That's confusing me. What difference does the valve stem diameter have to do with the retainer fitting the spring? If both the stock springs and the beehive springs are the same size at the retainer, I would think the stockers would work. Thanks for everyones input.

 

I would think that you would have to have a diff valve lock or that they would not fit right.

 

The valve stem diameter's are not the same between the LS type motors and the traditional small blocks. As Hog has said, Comp has hybrid retainers that will mate the LS type springs with the older style valve stem size. As far as the locks are concerned you would use the ones designed for a regular small block in the offset of your choice.

 

You cant use the GEN 3 retainer on a GEn 1/2 valve stem.....

TYhe GEN 3 and Beehive retaibners AND springs are teh shape of a Beehive, the top coils has a much smaller diameter than the bottom coils, therefore a special small diameter retainer is used.
A Gen 1/2 engine uses valvbesprings that have all its coils the same diameter therefore a GEn 3/4 or Beehive retainer will not fit with a GEN 1/2 spring.

This article will give you a visual. the GEn 3 engines use a Beehive style spring.
http://www.corvettefever.com/techart...vespring_info/

You can use the LS6 spring in a Vortec head but you will need to use the appropriate Beehive retainer, as the stock Vortec retainer is much too large to work with the spring..

i would use the 26915 Beehive springs with teh steel retainers in a Vortec application.

Beehive springs and retainers will be good for .530" lift on stocl L31 heads.


Stock locks can be used with all.

peace
Hog