Just wondering, what type of hp can a 28 spline axle take(4bolt)?? IS there a magical #? Im wondering if i should invest in a 31 spline and convert to a 5 bolt pattern, within the next 5 years im hoping the mustang will be pushing between 450-500hp (yes 5 years, damn budget).

 

I have had my stock axels in the car since I built it. I have gone a best of 10.90 's on the same axels. I have just recently upgraded to 31 spline axels just for the simple fact I dont know how much more they will take. I also stepped up the power level so I think I need them. Hope this helps.

 

I appreciate your reply, but you didnt give me any idea as to how much hp you were pushing.

 

im guessing 450+

 

I have seen stock motors break axles if your planing on running sticky tires. It all depends on how much rpm you leave the line with

 

This is somewhat an answerless question. I have run 10's with stock axles and on the other end of the spectrum I have seen 12-second stangs break them. There is no ‘magical number’ and no matter how many guys tell you they ran quick with them it doesn't guarantee you won’t break yours. Also if it was a indeed a ‘number’ it would be a ‘magical torque figure’.

The best bet it always seems is to find another housing that can be built as you can afford it and pull yours when the time comes. You can then sell it and recuperate some of the money you spent on the other one. The nicest route is to get lucky and find one that is already done right with very little time on it and save a few bucks in the process.

We had a car that ran 10.60's @127 for a season that used stock axles & the original posi (both had 115,000km on them) and that was with an EFI 306 with a 150 shot. The best 60' with that combination was a 1.47.

The only reason I can see this thing lived at all was the due to the fact the car was relatively light and it was an automatic. How long it will live will be based more on the weight of the car, the rpm of the launch and how much it actually hooks.

 

I agree with 82306 on this, there really is no magic number. I was running 26X8.5 MT Drags with a five speed and I was leaving at about 4500 rpm.