I am at my wits end on this one.

I recently finished a head and cam swap and I can not get the base timng set.

The aftermarket ECM I am using lets me lock timing at 10 degrees BTDC. By doing this it does not advance the the timing at all when locked. Stays at 10 degrees BTDC. This is the same thing as disconnecting the bypass wire on a stock TPI car.

Now the problem I am having is that there is no way the car will start if I do it as descibed in my manual for the ECM nor will it start mechanically set at 10 degrees BTDC (ex, set balancer 10 degrees BTDC to zero on tab, then line up rotor with cap post for number one cyliner). This worked beatifully with the previous heads and cam and using a triggle angle of about 80.

It will start though at 35 degrees BTDC with no problem with a trigger angle of about 45-55. This is not right by anymeans. Yes I went to a larger cam but come on the car should at least atempt to start with only 10 degrees BTDC.

Something is not right and I am out of ideas at this point.

What I do know:

Cam was degreed in and was right on the money, no advance or retard.

Cam is installed straight up (dot to dot) no advance or retard.

Distributor is in correctly not 180 out.

Ignition module and distributor are good.

Coil and pickup coil are good as well.

When the car does start up and I am looking at 35-40 degrees advanced BDTC with a timing light and timing locked at 10 degrees via the ECM it sounds great with very very little back fire through the exhaust. Throttle respnce is awesome and just overall sounds like it should.


Any thoughts or suggestions?


Thanks

 

Uh...maybe you could let us know what setup you're using?

Have you contacted the manufacturer?

 

Sounds like you have a stock balancer and a replacement timing cover.

The mark on the stock balancer is expecting the timing mark to be at about 12:30.

The tab on a typical aftermarket TC puts 0° at about 1:30.

That's about 30° difference.

"The simplest expanation that fits all the facts is usually the right one."
— Occam, ancient Greek philosopher, from back when the timing mark was on the flywheel instead of the balancer

 

Nope, aftermarket balancer that puts the timng mark around 2 oclock, and an aftermarket timing tab that bolts to the timing cover. This was used before with my previous combo with no problems.