How strong is the stock rear end?

[spiers]

Hey I have an 88 Mustang GT with the stock rear end still. I am about to put in some 4.30 gears and Hoosier radials... I am just wondering how long I should expect the stock rearend to hold up :??: I plan to run high 11's NA for now and hope to get some 1.6 60fts. And sooner or later high 10's on N20.

It has about 100k miles and also if theres anything cheap I can do to strengthen it for now I am open to suggestions, but I am on a budget.

Thanks

 

[FISHTAIL]

That depends. It depends on your cars weight, power level, and trans type. Assuming your at or near full weight, making good power and running a stick car with drag radials, I'd say your rear probably won't live very long.

If your running an auto, with E.T. streets at a lower power level in a lighter vehicle, then they'll live longer. There really isn't anything "cheap" you can do to help much, but the upgrade to 31 spline isn't all that expensive, so it all depends on your definition of cheap.

If you can afford it, i'd go 31 spline in the rear with C-clip eliminators and forget about it.

 

[spiers]

Right now the car is about 3400# raceweight, 375rwhp, 6speed manual. Keep in mind the car sees occasional track time but most action is on the street. Hoosier DOT 315/30/18 and 275/50/15

Later I plan to add a 150 shot and upgrade to 31spline but I was just wondering how long it would last for now...

 

[FISHTAIL]

Hard to say man. You might get lucky, and you might not.

 

[blownfox]

Right now the car is about 3400# raceweight, 375rwhp, 6speed manual. Keep in mind the car sees occasional track time but most action is on the street. Hoosier DOT 315/30/18 and 275/50/15

That is pretty close to my old setup (370 with a T-56), but my rear tires were 275 on 17's. My ear end is still together and was for the most part stock. I do have moser axles ans a auburn differential.

 

[spiers]

Would it most likely be the diff or the axles to fail first ??

 

[93sspcoupe]

Would it most likely be the diff or the axles to fail first ??

axles for sure lol. btw why you gonna use a 430 gear? are you gonna turn it 7k? if your only gonna turn it 6200 use a 373 at most. i imagine your setup is a hci 331. i have a hci 347 making less power than yours and its got a 355 gear.

 

[spiers]

I got a good deal on the 4.30... Im going to turn it ~6500 and using a gear calculator showed these will be perfect. My setup is a little different than yours lol.

So lets just say I had better axles from Moser already and threw them in and kept the stock posi unit... would this hold up to some 1.6 60fts and low 12s/high 11s??

Also the gears are Ford Motorsports brand, are these known to be a better brand?

 

[93sspcoupe]

i know your setup is different lol. the stock axles will hold 1.6 sixty foots. but your gonna be on borrowed time. i wouldnt buy stock spline moser axles. just do 31 spline axles and carrier. you can get a 31spline carrier from a v8 explorer also. i'm running stock ranger axles in mine and they held 1.6 sixty foots, and there still intact lol

i like the ford racing gears myself.

 

[spiers]

Cool I guess I will just run it til it breaks then do the Explorer carrier and 31spline axles. Hopefully that will hold up to some high 10s with a 6 speed

 

[spiers]

I can get Moser axles for $100.... thoughts ??

 

[rustyruststang8]

Cool I guess I will just run it til it breaks then do the Explorer carrier and 31spline axles. Hopefully that will hold up to some high 10s with a 6 speed

thiss what i got with 373s and a 100 shot it works out well. i spent 100 on the axles and 50 on the carrier.

 

[93sspcoupe]

I can get Moser axles for $100.... thoughts ??

if you can get them that cheap you may as well use them. but they will still be on borrowed time lol. are you gonna be doing a 6500rpm dump on spray or what? how do you plan on leaving the line?

 

[spiers]

Well its a 6 speed and I will have Hoosier radials and you know my power level so... Ill be dumping it wherever it need be. I just figured if the stock axles were the weak link then some Moser's for 100 would be a good idea and then wondering how much abuse the posi will take.

But I spoke to a local drivetrain shop who specializes in differentials and manual trannys, and works with a lot of mustangs... says at my level I should be perfectly fine with stock axles/diff. Says unless I am running 10.50s or better dont worry about it. Says he has had them in 10 sec cars with a manual tranny.