which housing is stronger???? 99 or 03/04??

[THEWOODKING]

i hav a 99 cobra and are wanting to do an eaton swap so the power would be about 470hp 420tq. would building my rear end with a 31 spline trac lok and 31 spline axles both out of a 04 cobra be sufficient for that ideal power??? also is the 99 differential housing the same/weaker than the 03/04 housing???

 

[sur_real1]

I don't believe there is a difference in the actual housing. They are built out of the same material, only difference is what is inside from what I understand.

 

[99riocobra]

yea, from what i have read it seems the dif housing is the same from 99-04.

 

[no_slow_svt]

I don't believe there is a difference in the actual housing. They are built out of the same material, only difference is what is inside from what I understand.

you guys are both right on.

the 03/04 have 31 spline guts with better haft shatfs. the housings themselfs are the same

J

 

[brkntrxn]

03/04 diff guts and 03/04 halfshafts will handle that power... as long as you are not stupid with it. I have well over 600hp and I have yet to break a halfshaft in my 99 with an 03 setup.

On the other hand, I have 340 or so hp in the 01 and have broken two halfshafts.

LOL, depends on how you treat the IRS and nothing more. Your feet will determine the life of that rear end.

 

[THEWOODKING]

would the 03 setup handle that power if i were to do all the recommended brace and bushings??? i want the rear to be able to handle that power and be reliable

 

[brkntrxn]

What are you going to do with the car? And how are you going to treat it? To answer your question, a fully bushinged and braced 03 IRS will take more abuse than a stock 99 IRS. However...

Like I said above, how you treat the IRS is what ultimately determines whether or not something breaks. The 28 spline 99 IRS will live with lots of power under the hood as long as you don't "shock" the driveline... meaning, hard launches and shifting and wheel hopping.

It is not just drag racing that breaks the halfshafts... in fact, the two I broke on our 01 were no where near a race track. It is all in how you treat them. If you are prone to dumping a clutch at 6,000 rpm, it doesn't matter if you have an Eaton posi and Moser 31 spline straight axles, something is going to break sooner or later.