Hi all...

Just had a new diff put in my car... Its from an ED. (My cars an EA S)

The car seems to pull a lot harder however, doesnt seem to have as much pickup as before. Would it be the Diff that has caused this>

At the same time as the diff, i also had the head replaced due to a rather large crack.

I think, but correct me if im wrong that a new head should not have this affect.

the ed diff may have different gearing to the ea which could effect the way your car excelerates

EAs had a low gearing diff... eg a 2.97:1 in a fairmont ghia manual... and they were 25 spline. The EDs are 28 spline, and are a minimum of 3.08 for the base models. But depends on the model...and the engine... if its a V8 LSD, it'll be a 3.27:1 V8 diff, with the XR6 LSDs, or the Fairlanes, and Fairmonts with LSD it was a 3.23 (i6).
So I would say that the gearing has changed.
Did you change the drive shaft aswell? or the flange on the diff?

As for the head... EFs had a better flowing head, but unless its an XR6 head, it shouldn't make that much of a difference, unless the crack was a substantial power loss.

Cheers