3.4L Valve spring question...need advice

[viper98885]

I recently had my 3.4L heads ported and polished with a 5-angle valve job done with flow charts. I kept the stock valves and I am planning on keeping the stock cam in it for now until someone can start reprogramming the V6 computers again for an aggressive cam. I have roller tip 1.6 rocker arms now, but will be switching to the full rollers when the heads are installed. My question is whether or not I should replace the valve springs with some LT1 springs now or wait until I do the cam job. I am planning on replacing them no matter what but would like some input about whether I should use the stock spring rate or upgrade to the LT1's. Thanks in advance

[MustangEater8251]

You are still using the cas iron head right?

Basicaly a direct palgarism from some stuff I read up on.

production Valve springs and reatainers are satisfactory for hydraulic camshaft prfiles with .420-inch or less maximum lift. Chevy dual valve spring PN 330585 and aluminum retainer PN 330586 can be sued with mechanical cams with .560-inch or less net valve lift. this spring is 1.379-in in diameter , and produces 135 pounds of seat pressure at an installed heright of 1.72_in. v6.60 cylinder heades must be modified to accomodate this spring by enlarging and deepeneing the valve spring pockets. Instal aftermarket vavle stem seals for oil contorl when suing these springs.

Jsut some extra info. [img]smile.gif[/img] If you are using the stock cam I think you should be alright, but you mihgt want to consider putting new ones in if the stock ones are tired. Anyone have any info about how long it takes for stock valve springs to start not working to fll potential? If I do head work i was thinking of replacing my own at least.

[GordSipko]

Don't use any more spring than what is required for the specific camshaft. Use the spring recommended by the cam grinder.

There are no gains from using more spring. The downside is small power loss because of more friction and higher wear rate on cam lobes, lifters and all valve train components.

[viper98885]

For the time being, I will be using the stock cam until computer reprogramming is available again. I guess that at this time, I will use the Comp Cams 802-12 springs. Thanks for everyone's help!

[ May 28, 2002: Message edited by: viper98885 ]</p>