difference between the OHC 3.9 & 4.0 blocks

[Anonymous]

Does anyone know if the 3.9 is is the same block as the 4.0 , does it have
the same bore potential as the 4.0 or are they more limited, thanks

 

[Anonymous]

3.9 pistons were a small diamater to the 4.0 engine. For my 4.0 EF engine I used ACL race series 3.9 pistons with a 1mm oversize. they were almost a streight fit, and the engineer siad all that was really needed was a light hone but I got him to do it propelly. I've got a very good articille in a Performance engines mag that goes really indepth into a 3.9/4.0 engine build-up (STD specs but lots of extra info on performance upgrades).
I would post it but don't really want a copy right law suit against me, but if you want email me and I'll scan it a send it to you.
snailracing@lycos.com