Thread: Timing Problem with GM Crate Engine

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I have a technical question on a GM Crate Engine that I purchased about a year ago. I’ve just got around to installing in a Camaro that I am restoring.

The car is not street worthy (no windows, no lights, no tag, etc.) at this point so I am unable to actually drive it anywhere for mechanical assistance.

The engine is a 350 HO Deluxe (330 HP) – P/N 12496968

The problem I am having is that I can’t get the timing to set where it needs to be – 10 degrees BTDC at 700 rpm.

The have tried setting the timing with the rotor pointing directly at the #1 cylinder (with piston at TDC) as well as 1 notch forward and 1 notch back.

It runs best directly pointed at #1 but I don’t have enough slack in the distributor (retard or gain) to get it to 10 degrees – the range I can make is 8 degrees after top dead center to 0 degrees (and 0 is reached with the vacuum canister on the distributor bumped against the intake manifold). The idle is rough and the engine sounds like its missing. I did drive it a short way down my street and it ran very sluggish.

I have replaced the distributor (HEI), plug wires, and plugs – none of these have helped the situation.

I am looking for technical insight on what else could cause the problem I have described.

Thanks in advance for any help you can provide.

Rocky Phillips

I'm not sure what you mean by "one notch."

Pull your distributor out and rotate it one tooth clockwise. That will give you enough room to further advance the timing.

I just got around to putting in my 9 month old GM crate (the 290HP version) into my '69 Camaro too.

Have you adjusted the valves properly with the engine running? I was just able to get my engine to idle at a low enough RPM to adjust the valves and it made a really big difference. My #2 intake was way too tight, once I backed it off the idle smoothed right out.

I've tried moving the distributor up one tooth and back one tooth - which helped me to obtain an initial timing of 10 degrees BTDC but the the engine did not run good at either position.

I have also set and reset the valves on two occassions but it did not resolve anything.

you might want to check to see if the cam was dialed in. my crate had the same problem. it was 3 degrees off.