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we’ve started on my camaro project the timming is off a little bit, my neibor dosent know if the cam is hydrolic or not is there a way to find out with out taking off the heads, it has roller rockers, it dosent sound bad but he thinks the lifters need ajusting but dosent know which cam it has thanks for looking

If you don’t know, then it’s probably hydrolic.

What timming is off? The ignition timming or the cam timming?

Roller rockers do not require roller lifters. However hydrolic lifters don’t need to be ajusted.

Who assembled this engine? I am worried that someone milled heads or something, and didn’t make the appropriate ajustments to the valvetrain geometry (pushrod length or something).

The number of people who have a self “rebuilt engine” that runs poorly because the timing needs adjusted is truly amazing.

There maybe some mechanics dislike not being able to alter the engine ignition timing (not refering to the OP) but I liked being able to tell the customer that the timing was not adjustable (when applicable). End of story.

If your rockers have adjusters on the ends with studs and nuts, you definitely have solid lifters. There are other ways to adjust solid lifters, but none so gender-specific. The manual should be able to identify what should be in there. I forgot which Camaro you have. If you have the manifold off, you should be able to see the lifters. Removing a pushrod will allow you to see the lifter with a flashlight. If you can see a little metal clip around the oil hole in the center of the lifter, you have hydraulic. No clip? Solid. If you never heard the lifters clacking when the engine is cold, you have hydraulic.

About the best way to tell is by removing a valve cover and checking to see if there is any clearance between the rocker arm roller and the valve stem.
With a solid lifter cam there should be some additional clearance.
With a hydraulic cam there should be no clearance at all.

Of course, this only applies if they were adjusted properly to begin with.
Next step would be to remove a rocker arm and extract a valve lifter. This can be done with a lifter extraction tool which is usually available for a pretty reasonable price at many auto parts stores.

If I remember correctly, this is an 80 model Camaro and ignition timing has a bit of leeway on these cars. If it’s running poorly the timing may not be the issue as a little bit off should not make much of a noticeable difference.

I have tried to tell people for many years that in order for timing to make a difference in idle quality (not speed) the timing must be way off,the same goes for over heating,Idle speed is easily affect by a small as 2 degrees of timing change.

We had a SAAB 900 that at times showed starter heat soak symptons,The Service Manager had me moving the timing 2 degrees retarded from the factory spec. thinking it would fix it,what a idiot,he was later fired for his “liquid lunch” habit.

thanks for your reply the neibors son came down today it is a solid cam had it running like a top in less than an hour, couple of valves to tight

I think I can count on one hand the number of sharp service managers and service writers I’ve been around.
Most of them, especially the serv. manager types, generally cause me to pull more of my hair out because of blatant ignorance.