Installed a 4.10... observations.

[Ccmano]

Hey folks,

As some may know I bought a very low mile 4.10 pumpkin from LocoBob (thank you for a great deal!) and installed it this past week. Since I'm still unemployed, it gave me something to do in my spare time.

It turns out it's one of those "why didn't I do this earlier" mods. It really improves the drivability of the Z, especially around town. I literally have to re-learn driving the car, it's that different. Around corners it does require more carefull throttle application. Needless to say the change in the felt acceleration is very noticable in all gears. Haibeck states it gives an 18% improvement in usable torque in all gears. I now believe him.

I didn't take any pictures of the install (probably should have) but I will relate some observations of the process. It's not difficult, just time consuming, especially when your doing it for the first time like me. As in all things of this nature, next time I'll do it in half the time.

I took the time to replace all the rear suspension bushings since most everything was apart. Another very worthwhile job. Now that the bushings are in, you can really feel the difference. 20yrs is a long time for rubber. I went with "PST" polygraphite bushings to minimize squeek. So far they are as advertised. They sell a kit for the rear only for $95. The rear end really feels solid now. With the exception of the diff carrier bushings they are all very straight forward in terms of the removal and install. The carrier bushing threw me for a loop until I realized that the outer metal sleaves had to be removed to install the new ones. Half an hour with a hacksaw, punch and hamer and they were both out with no damage to the carrier.

I cleaned everything, especially the mess from the leaky halfshaft yoke seal. Ultimately I found that steam cleaning with some help from "PurplePower" cleaner was the way to go. I picked up a handy little steam cleaner made by McCulloch on sale at Harbor Freight for $79. It had good reviews on the net and while not nearly as effective as a commercial steam jenny, working together with the cleaner it gave very good results.

While I was in there I also replaced the halfshaft U-joints (actually found a bad one) and installed C-beam plates. All of this went without a hitch. I did find that installing the C-Beam plates on top of the beam was a little tricky due the tight quarters and my large hands.

I remembered to mark all the rear alignment adjusters so that they could be put back where they were upon reassembly. This at least gives you a basic alignment. I have an appointment on Monday to get a full 4 wheel alignment, the front needs it anyway.

I worked with the car on jack stands and found the job to very do-able that way other than the soreness of my 55yr old body from all the up and down and working over my head.

So, for those of you thinking about doing this mod, I hope this gives you some more insight into the process and the results.

H