1bdbrd

iTrader: (1)

im going to be running a cc306 (230/244 .544/.576 112LSA) cam in my L98 with trick flow 23° heads and a converted lt1 intake. im kind of confused though about the valve springs. i have a few picked out based on advice ive read in the LT1 section on cz28.

i have about 3 choices:

Comp 918 beehive springs-several say they run these with little problem even on bigger more radical cams than the 306. they are also claimed to be lighter which helps eliminate valve float at higher rpms. problem is, they are expensive.

Comp 987-these are a dual valve spring design but are much heavier than the 918. they are also the cheapest at 85 bucks a set.

Crane 10308-havent read much of anything about these. i know these will work though as a few have said they ran them at one point with the same cam.

the car will have stock replacement new LT1 OEM lifters from GMPP, comp 1.6 pro mag roller rockers, hardened custom length pushrods, GMPP guide plates and the aforementioned trick flow heads. any thoughts?

Dragonfire383

Personally I like the advantage of the "beehive" style springs, Your less likely to run into coil bind, which is something you'll want to check. Secondly, you'll want to make sure that the heads can support that lift. I also suggest calling the CAM manufacturer and see what they recommend: too much spring can lead to excess valve train wear and eventually failure, Too little equals valve float, and possible engine trouble. Good luck

PS. this is an edited post.

1989GTATransAm

iTrader: (3)

My vote goes for the Comp 918's. Has many advantages over conventional springs. Valve springs are only part of the equation. You should use a stiff rocker arm such as the Comp Pro Magnum and a stiff pushrod such as the Comp High Tech or other similiar pushrod. You don't want the pushrod to act like a pole vault.

racermike

Another spring to consider is the Comp 26981 which is a 1.25" beehive.It is a replacement for those who don't want to machine their heads. From Summit it is supposed to be shipping on 5/03/06.
I agree about using quality pushrods and rockers. Mike

1bdbrd

iTrader: (1)

i was kinda leaning towards the 918 springs myself as well. and ya i would run pro mag rockers and hardned pushrods with it as well. the heads can support the cam as they are trick flow 23° heads.

89gta383

iTrader: (5)

I don't think the beehives are worth the price, I would run the 987's and some titanium retainers. Both of those are still cheaper than the beehives alone.

1bdbrd

iTrader: (1)

what is the valvetrain weight going to be like with 987s and ti retainers compared to 918s with regular retainers?

89gta383

iTrader: (5)

Don't know, you could find it on the web somewhere, but unless you plan on spending lots of time above 6500-7000 rpm, I wouldn't worry about it, it's not that critical.