Ok right at the top I did not assemble the engine it is supposed to be a 408 stroker the owner purchased the short block assembled by an unknown party. The goal of the 71Boss 351 is as stock appearing as possible so stock exhaust manifolds,complete stock exhaust stock numbers correct damper.
The damper has had the offset weight machined out so the Assumption was the engine is internal balanced so a non counter weight flywheel was purchased.
Now a few problems I’ve found.
First on first fire up it leaked like a sieve, upper half of rear main backward….
Got that fixed and started again.
Setting floats
Verify idle
Alt charging
Set base timing
Rolled throttle off idle to about 2000-2500 and the engine just chugged and shook…..
I looked at timing again a verified it was only 25-30deg total.
After talking with an engine builder friend he tossed out rotor phasing. I set up to test and at base 15 deg the rotor was well past the No.1 post….hum.
The vacuum is disabled on this correct,less Pertronics, date coded distributor so the timing plate was locked incorrectly.It is important to the owner that the correct date coded vacuum can be in place even though it doesn’t work.
I reset the phasing and frankly it was much better I was able to verify total timing all in at 2800,36deg.
But still that growl /shake ….
In the past I have mistakenly installed a 28inoz flywheel on a 50inoz engine it didn’t growl but did feel like it was going to jump off the jack stands at 3000rpm.
I’m open to any suggestion at this point.
I feel the engine needs to come out but just want to ensure it’s not a tune issue of some kind.
Easy things first.
I’m going to pull the starter and ensure there is no counter weight on flywheel,I put it on but didn’t take note because ,well “that’s the right one”.
Next pull clutch…..
Beyond that any ideas?
Thanks for your help I know there are some very knowledgeable builders here that’s why I’m asking.
