mckay

I have a 65 with 2.80:1 ratio 8" rear. I want to upgrade the gears. Suggestions of what I should do and why.

1. Upgrade pumpkin to 4:11.
2. Swap rear for 8.8" rear. (what is a good swap: requires very little modification/fabrication?)

3. Other suggestions?

Thanks

humpbackshooter

Is yours a 4 lug? Are you going to 5 lug if it is 4 lug?

Hump.

Starfury

We definitely need more information to help you out.

What engine/cam?

What transmission?

What kind of driving do you do? In-town? Freeway? Combination? Street/Strip?

mckay

my main question is Is it better to swap entire rear end for a 9" or just to replace the pumpkin with the gears that i want? I have a 4 speed manual but thats all i know about it. That i will upgrade.

I have realized 4.11 is a little agressive for what i want. it will be street highway driven. i dont plan on racing it. i found that with a 0.63 5th gear and 3.80 rear i can get get 70 mph at 2200 rpm or 2000rpm with 3.55.
it is a 5 lug

racer_dave

Its easier/cheaper to just change the gears. It isn't hard to do, but you have to be comfortable doing the mechanical stuff. I'd swap to a track loc diff as well since it will be apart. Sure a 9" is a lot stronger, but the 8" is fine for most street cars, even if they've had some HP increase in the engine.

mckay

What would be the advantage of going to a 9"?
Why stay not stay with 8" (money aside)?

fastbackford351

I kept my 8" and recently ditched my factory peg leg 2.80's and installed a 3.26 tracloc setup and I couldn't be happier. It didn't kill the highway cruising with excessive rpms but gave a nice additional low end boost.

The best part is now I can lay two strips of rubber instead of only one and looking like the loner with the boner.

Gun Jam

im running a t5 with .63 od and 3:80 trutrac diff and an 8" diff. I have no complaints about any of that stuff. Im making about 290hp and 300ftlbs at the wheels and the 8" has been fine

-Gun

Starfury

I'd only recommend a 9" if you really need the extra torque capacity. I have a pretty stout 331 and my 8" handles it just fine.

An 8.8" is a good upgrade for a 67-68 car (and possibly 69-70?) because the width is just about perfect. Anything else will require some engineering to get it to fit properly. Since you have a '65, if you were going to swap I'd just recommend a 9".

mckay

Thanks, I think im going to this route. I have already found a 3.80 with trutrac that I think I will purchase.