ballajb

I am doin the EFI swap into my Mustang. I have a built motor that will put out maybe around 325rwhp. Will my 8 inch rear end stand up to this power?

fakesnakes

Avoid slicks and continuous clutch dumps and you will be fine as long as it is in good working order.

Starfury

+1

With a good 4-pinion diff, you'll be just fine on the street.

dcohen

8in's are a lot tougher than some people think

are you going to rebuild it or leave it stock?

jspagna1

Ya you should be fine. Anything with 400+ horsepower is when the 8" may be an issue. I've had an 8" in my car with 3.55's and slicks for the last 11+ years and so far so good. But my cars an automatic and I don't beat the **** out of it regularly.

ballajb

Yea I do plan on building the rear end over, but not right now because of how much I spent on building up my motor and the cost of parts for the efi swap. So I was just wondering if it would last for a couple of months or so or if it was something I needed to do right now. I was looking at mustang unlimited site and the posi unit and diff is like $400 and then I was thinking some 3.80 gears they had for like $184. The gears in the rear end now are 3.00's

Starfury

Nah, it'll be fine until you can update the diff/gears.

When you do swap, however, you'll need to factor in labor cost. That, or buy an entire third member ready to bolt in. Setting up gears in a rear end isn't extremely complicated, but it requires special tools, is very easy to screw up, and isn't something I'd recommend most people attempt on their own. Either way, you're usually looking at $800-1k, unless you can find a really good deal on one.

68dustin

i'm in your same boat... i have a pretty build motor around those hp #'s and i already blew an 8" apart. I then rebuilt it and have the stronger casing with 4:11's and a stick with slicks. So far so good, I drive the **** out of it banging gears as hard as i can. However im looking to upgrade to something stronger since im now installing 10lbs of boost to it. If i were you dont waste your money on the 8" and go with something bigger. I can now count up to about 1200 bucks that i have spent on the 8". At the time "yeah i thought i would be happy with 340 or so hp.. but now look.. i got bored and am going with more power." Soon or later you will upgrade to more power....

ballajb

Yea, I just didnt want to fork out any more money right now after all I spent on the motor and the things for the conversion. I just wanted to be able to relax with this rear end even though I know I wouldnt feel all the power I want since it has 3.00 gears. But yea that is a good idea for me to just look into a 9inch instead of puttin money into this 8inch

68dustin

ive been looking into the 8.8's. ive had good reviews as well as bad.. but they are cheap and easy to find. Also they are stronger than the 8"