Hi Guys,

I am putting my LQ4 into my 74 camaro with a 02 Z06 cam & valve springs turbo 400, with 3.73 gears. I have 2 engine build books on LS motors.

Neither of these books address's adjustments on the factory roller rockers. My friend who is super experienced on building small block chevys, but has no LS experience looked at my factory rockers and claims the LS rockers are not adjustable and I have to get roller rockers to put a Z06 cam in. But I know a lot of guys are running after market cams with the factory rockers.

My noob question is where is the adjustment? Is it just getting the right length pushrod to match the cam lift and the hydraulic roller lifters take up the slack? So the key is the proper length pushrod with no rocker adjustment?

I know this sounds dumb but where is the rocker adjustments for valve lash etc? After market roller rocker have the surrounding nut with the allen bolt in the center to lock it down for adjustment. I am quite sure I dont need aftermarket roller rockers for a street/strip cam.

Sorry, I am brand new to installing a cam and adjusting valves on the LS motor with factory roller rockers.

Hpbob1

 

Long story, short.... Yes. Correct pushrod length, torque rockers to 22lb/ft.

 

Hi SweetS10V8,

So when installing a aftermarket cam into my LQ4 the only adjustment in the valve train (besides upgrading the valve springs) is the proper length pushrods and then torqueing down the rockers to 22ft lbs?? Just need to be sure. My small block chevy steeped engine builder friend is very skeptical on that. But again he has never done a LS motor with a hydraulic roller cam. I have heard of guys running up to 590 or 600 lift with stock rockers.

Hpbob1

 

Your rockers will be fine and if you haven't milled the heads down anything crazy or decked the hell out of the block a stock length 7.4 pushrod should work just fine for you. Only time you need to worry about changing length is with certain small baseline ground cams, and when you start changing geometry on the engine setup milling heads, block surface, etc.

 

Hi WYATT318MOPAR,

Wow so your saying even when installing a higher lift aftermarket cam I dont need to change pushrod length to adjust for the increased cam lift???

I am having a mental block on understanding this. Doesnt the higher lift of the cam lobes come into play here? I do plan to upgrade to beefier wider pushrods.

Amazing, so the hydraulic roller lifters somehow make up and adjust for the higher lift of the cam? About to order my cam and still a confused newbie in this area on LS motors.

Hpbob1

 

With a low lift cam 7.400 could be fine, more lift you add smaller base circle becomes, generally around .600" lift you need 7.425 pushrods.
You will need better vavle springs, something like PAC 1218 are best springs for up to .600 lift. Factory replacement too, works with stock retainers.

Factory rockers people have taken to .660" lift no problem.

Fraser

 

the factory rockers are good enough and lighter then some of the aftermarket rockers they sell, mine are running at .610 lift with no issues yet. i have a smaller base circle so my pushrod length is 7.425. tighten up the rockers till there is zero lash (spinning the pushrod should get hard to turn) then count how every many turns you make till the torque wrench clicks at 22 ft lbs ideal would be from 1/2 turn to 1 full turn (somebody correct me if i am wrong here)

 

Your post says Z06 cam that is far from high lift, lift doesn't have any affect on pushrod length it is all determined by the baseline that the cam is ground on typically the larger the cam the smaller the baseline in order to gain lift and still be able to fit the cam through the actual bearing and install it. This is the same principle on any pushrod engine not just LS series. I am not sure what your talking about when you say, "beefier wider pushrods" hardened chromoly is the way to go. Your pushrod length determines the preload that is put on your hydraulic lifter and it acts as a take up device for slack in the system keeping constant pressure on both the cam and rocker arm not allowing the components to chatter as many adjustable setups do when not properly setup