Question about HP and relation to tranny/rear.

[Fett]

Someone at work brought up an interesting point today....one that I didn't think I would be facing so soon.

With my mystery nitrous shot, I went from a 13.1 to an 11.8. So now I begin thinking of what I might break. I have used a few different online calculators to see roughly what kind of power I am pushing...I know the calculators aren't accurate, but I guess they give me a round-about idea. With a 3200 lb car, it takes roughly 350+rwhp to run 11.8....assuming it takes more Tq, I wonder how long my WC T5 and my 28 spline rear is going to hold up. Mind you, this is also my daily driver...so I don't want to find myself with a lot of down time.

I think I have a line on a 31 spline rear chunk, and a set of 31 spline axles that are for a 79-93 8.8 Mustang with rear drum...which I plan on keeping. So I think I have my rear end solved. I am assuming that I would be better served to also put in some tq-boxs as well. I have Steeda tubular lowers and some Steeda boxed uppers with urethane bushings and Steeda full length subframe connectors. So I am thinking that the 32 spline axles and chunk plus tq-boxes would pretty much assure me that I won't break anything. But what about the T5?

I dump the clutch at 5000rpms and spray at WOT from the hole...with my slicks, I wonder how long the T5 and KC clutch will hold up. I don't go to the track every weekend...but enough to want to try to not break something.

I didn't think I would have to worry about having too much power for a LONG time, and I don't know if I really need to worry about it yet. But I still plan on getting rid of my stock heads and get a better cam...so I want to get more power from the motor...plus the nitrous. Basically I am hoping for 11.50s. But either way, I don't want to break anything NOW.

Am I worried about nothing?

 

[86bluecobra]

Personally I know what your talking about. I'm in the same boat. I have had 6 T-5's in my car. I keep buying 300 dollar used ones from other mustangs that have already been beaten on. Finally I got a freshly rebuilt WC t-5 and have had no problems for 2 years. The TKO 500 or TKO 600 would be the way to go if you never wanted to worry again.


Now about the rear end. I also have stock axles and 2 years ago I snapped one. Once again I went to the bone yard and pulled one out of a 5.0L and haven't broken anything yet. I will at some point upgrade to 28 spline moser axles. I really don't see the need to change my carrier and everything else when it wasn't the spline that let me down it was the axle itself. I think that 28 spline aftermarket axles will work just fine for the power our 2 cars are making.

Now about your clutch. I also have tha same clutch you have. I don't really like it. I want the center force dual friction again. That being said the stronger the clutch you get the more likely to damage the tranny and rear end you are. So really its a catch 22.

 

[BlooDReigN]

I'm kinda worried about this as well...How long was it before you finally snapped one of your axles?

In the beginning of May I'm hoping to run my car @ the track with a set of slicks on, and I'm kinda worried about destroying an axle. I'm not worried about my TKO...but I'm quite scared for the rear end.

 

[RYC CUKR]

is the 31 spline chunk that you have a big pin (high torque, 7/8" I believe) or the standard pin, 3/4" pin? If it is the standard pin you can actually swap the spider gears and guts out of the 31 spline chunk into the 28 currently in your car and not have to worry about setting backlash, and shimming the diff so it has the correct wear pattern. This is especially nice if you have gears that you want to keep and not have to swap to the new diff and have them set up properly. This only works if its a standard pin diff.

On transmissions and clutches. Until you upgrade the trans do not upgrade the clutch. The clutch is kinda the fusible link in the driveline. It should slip before you actually break something in the driveline. A fresh WC t-5 would probably give you some cushion. If you want to do it yourself you could get a kit from g force or astro. I have heard good things about both.

It would be nice to have the parts in the garage ready to JIC for both the rear and the trans.

 

[Fett]

I got my 31 spline chunk today, it is from an IRS Explorer. I wanted to redo my clutches anyway and re-shim them, so I will rebuild the chunk before doing the install. I should be getting my 31 spline Moser axles tomorrow, they are stock length, 5-lug...so I will not have any brake issues. It should be a simple install. Then I won't have to worry about the rear end for a LONG time.

I am not going to touch my tranny right now, I figure if I do break something...it should still be driveable to a point. So I will cross that bridge when I get to it.

 

[millhouse]

Just something to keep in mind….when your tranny finally lets go (and it will), it will be virtually worthless. I'd say sell it while it still can bring in some money…and it will allow you to recouped some of the cost to switch to an alternative tranny.