How to date a late 80s 5.0 HO motor?

Are there casting numbers (or other clues) for dating a late 80s 5.0 HO long block without surgery? For some reason the harmonic balancer is dated E4xxx (84) but it has a Roller cam firing order and I was told the motor is late 80s. I'm trying to finger out if it has forged pistons (88-89)

Look for a date code on the block near the starter...

Does it have the air intake on it? Speed density was 86-88, MAF was 89+.

Originally Posted by PaceFever79

Are there casting numbers (or other clues) for dating a late 80s 5.0 HO long block without surgery? For some reason the harmonic balancer is dated E4xxx (84) but it has a Roller cam firing order and I was told the motor is late 80s. I'm trying to finger out if it has forged pistons (88-89)

Hate to always be the one that brings this up...but, with any car - especially Mustangs, after the first year or so on the road, there will almost always be some modifications. We are 20 years into the cycle for the early 4-eye Mustangs, I seriously doubt if there are any "stock" foxbody Mustangs left.

Add in the fact that you can mix 'n match most 302 blocks, heads, intakes - means you need to know your stuff when its time to go "yarding".

yep

Originally Posted by Beoweolf

We are 20 years into the cycle for the early 4-eye Mustangs, I seriously doubt if there are any "stock" foxbody Mustangs left.

Oh there still are some out there. Recently there was a 79 pace car on Ebay with only 108 miles on it!

The drivetrains in my 79 and 84 stangs are 99% original. The 79 has 39k with just the muffler an tailpipe replaced. The '84 has had the carb rebuilt, AC upgraded, exhaust replaced, and a few suspension mods; aside from the carb that's external stuff, so I consider the drivetrain stock.