my77stang

also make sure your using correct balancer and flywheel / flexplate for the later model 5.0

the early motors were 28 oz and the later model (anything with a one piece rear main seal) have a 50 oz balancer and flywheel / flexplate

JamesW

That's one thing nice about going efi...and using all the 5.0 parts. No messing with distributor, timing cover, pulleys, flexplate or flywheel, etc....

bl28ma

I had to get the correct flex plate (50oz) for my setup. I had the rotating
assembly checked and balanced with the 66 harmonic balancer. I'm putting the front end (timing cover) of the 66 on the 87 block. I put a stage 1 trick flow cam in it. And using a pertronix distributor.

my77stang

wait you had it balanced with a 28oz balancer and a 50oz flywheel? what-the-huh?

bl28ma

Yes, I'm using the 66 harmonic balancer up front and a 50 oz flex plate. The speed shop had to add weight to harmonic balancer. I took the rotating assembly to them to do this. They say it's within a gram.

my77stang

within a gram should be fine up to 6000 maybe 6500 with stock rod bolts. for the record, the single greatest thing any of you can do while building a small block ford is to upgrade the rod bolts. drilling them out to 3/8 takes too much meat away - but going with stronger 5/16 bolts so VERY HIGHLY reccomended especially if your planning to build horsepower with your new motor.

just my 3 cents =)