I am at the finishing stages of my 355 tpi install. I am having trouble with backfiring, which i am assuming is a timing issue?

We unplug the est, set the timing to multiple different settings between 0 and 10 to try and find out where it idled best. After shutting it down, reconnect the est, upon start up it backfires like crazy and advances the timing around 20 degrees.

The car will not back fire if i keep the est unplugged, and runs much better with it unplugged.

Any suggestions?

 

try checking your knock sensor

 

Knock sensor is new, i did wonder about the possibility of the open header causing false readings.


Anyone else wanna take a stab at it?

 

bump for you

 

anyone.......anyone..........

 

Did you verify that balancer and timing tab are matched?

In other words, when engine is at TDC with a degree wheel mounted, does balancer show 0 degrees?

If balancer or timing chain cover has been changed, timing might be off because of that.

 

Its a brand new balancer, and the motor was built just a week ago with the cam installed straight up.

 

There are different balancers with different TDC marks.

There are different timing chain covers with different timing indicator locations.

If they are not matched and you did not check it with a degree wheel when building the motor, then this could be your problem.

I would install a piston stop with motor at BDC, spin it around easily until it stops, and mark balancer at 0 degrees on timing tab. Next spin it around the other way until it stops, and mark balancer again at 0 degrees on timing tab. Halfway inbetween the two marks is TDC on the balancer. Measure it, split the nuts and mark the balancer there. See if it corresponds with the timing mark already on your balancer. If not, that is the actual TDC mark for your pointer.

An example, I installed a fluidampner balancer on my engine, an early 90's roller motor, and it was not even close. Fit the application, but marked for a different timing tab location.