I would like to know if i can get springs that will work with the stock lt1 heads , without maching the heads, is there a package deal with everything needed? I went to Norwalk last night (saturday 10 th) .....time to upgrade! Black Vette took me by a hair

 

You can order the EX-612 set of valve springs from Combination Motorsports, they work with the stock heads with no machining involved.

-B

 

Crane springs 99893 will also work.

 

Call Comp cams. I am using 918 springs for an LS1 on my car, they are good for something like .620 lift.

I am very happy with them.

 

ex-612 is what i used on stock heads it will fit right,call combination motorsports.

 

Hey Blown383 and Twister.....did you guys get everything with them, like new keys and stuff?

 

crane 10308 kit will work..thats what i used. Come with shims, locks, and retainers.
Marcin

 

yes it comes with valve springs, chromoly retainers and 7 degree locks.

 

So you are running the CC306 on stock heads?

 

i ran a 12.7 @ 115 with a 2.2 60' on street tires with CC306 and stock heads and not even all the boltons

 

right now i got ported heads but before i ran it in stock heads plus pcmforlless tuning for 3 months never had any problems.

 

Hey twister... How much did they cost????

 

i paid $104.97 for the ex-612kcm valve spring kit at combination motorsports.

 

All stock LT1 , except for the underdrive pulley,TB bypass,hypertech power programming,K&N air,170 T-stat,Nitrous is there but not completed,
I've heard that the hypertech programming will have to go from some people and others say it'll be ok, ??? listen for detonation i guess.
It runs low 14's now, I want low 13's, will the cc306 do it or is that too much for not having headers , heads and fuel sys upgrades ,inj's pump...
The added parts and software took off a little over .70 seconds of my 1/4 mile

Within a year i hope to add 373 rear gears ,headers , higher flow inj's and fuel pump, and some year a good set of heads and a blonde

 

You'll definately need headers at the least. But you still wont get the optimum performance outta the cam, in fact not even close with stock heads. You need to get some headers before a cam buddy.