How much HP is the stock 5sp tranny good for?
12-09-2004, 07:17 PM
#1
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How much HP is the stock 5sp tranny good for?
With all this talk of strokers and SC kits, what about the rear end? On the heels of Mark A imploding a tranny, what is the stock box really good for in HP before one has to think about upgrading?
12-09-2004, 07:27 PM
#2
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You have to remember the forces I put through my tans would be nearly impossible to duplicate on a street car. I have never heard of a gear failure on a street driven car.
12-09-2004, 10:00 PM
#4
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That's one of the reasons I don't plan on going for the mondo rubber on my stroker. There has to be fusible link somewhere, I'd rather have it be in rear tire rubber than trannys, axles, drive shafts (already broke on of those).
12-09-2004, 10:21 PM
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Originally Posted by atb
That's one of the reasons I don't plan on going for the mondo rubber on my stroker. There has to be fusible link somewhere, I'd rather have it be in rear tire rubber than trannys, axles, drive shafts (already broke on of those).
Especailly with a stroker!
12-10-2004, 01:23 AM
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There's more to it than just saying the transmission will be good for "X" amount of power. Stickier tires will be harder on the transmission. How the car is used will have an effect. The temperatures that the transmission sees will affect it. How a particular driver drives will make a difference. Where in the RPM range the engine makes power is yet another factor.
12-10-2004, 01:23 PM
#7
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Failure of trans has nothing to do with HP....it is all about Torque.
I have shred two gear boxes on the street...3/4th gears. When the tires "hook" up at the torque peak, bad things happen.
Of course, you could use 225 or 255/275 and have "safety valve", but then you lose traction and maximum acceleration!
The failure is a function of gearbox temperature...since it is alum, it expands with heat and the gears begin to spread, add torque, and the spreading become greater...thus "knocking off" some teeth.
Practical limit appears to be no more than 450 ftlbs tq.
Think hewland...
Regards,
Marc
I have shred two gear boxes on the street...3/4th gears. When the tires "hook" up at the torque peak, bad things happen.
Of course, you could use 225 or 255/275 and have "safety valve", but then you lose traction and maximum acceleration!
The failure is a function of gearbox temperature...since it is alum, it expands with heat and the gears begin to spread, add torque, and the spreading become greater...thus "knocking off" some teeth.
Practical limit appears to be no more than 450 ftlbs tq.
Think hewland...
Regards,
Marc
Last edited by Fastest928; 12-10-2004 at 02:05 PM.
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12-10-2004, 02:00 PM
#8
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Shane wrote:
True, but a 255 R-compound is a couple notches below the monster Goodyear slicks that Mark A is running.
Dude, I just want to be able to steer the back of my car like your S/C'd wonder did. Who'd a thunk that a 2.20 geared A/T could dance like that?
-Adam
Yeah we all know your just dying to get some mor r-compound tires to run at SRP. Especailly with a stroker!
True, but a 255 R-compound is a couple notches below the monster Goodyear slicks that Mark A is running.
Dude, I just want to be able to steer the back of my car like your S/C'd wonder did. Who'd a thunk that a 2.20 geared A/T could dance like that?
-Adam
12-11-2004, 05:13 AM
#10
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a "drifting" 928.....would be cool to see, but I feel sorry for the guy that owns it.....damm that would be stupid expensive...tires/clutch/drivline-axles/tranny...scary thought......drifting seems like a good sport for an old school solid rear axle car (think mustang) to me
12-11-2004, 11:22 AM
#11
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Hi Mark
I have hundreds of sets of Hewland straight cut gears, Mark if you need any. X-tract and Emco as well! I don't believe that to be the solution, however. The countershaft provides too much movement and withoug redesigning it and the bearing carriers, It don't think you can stop the flex. Really not that many people could ever use them let alone those that need them actually spend the money.
Good luck.
I have hundreds of sets of Hewland straight cut gears, Mark if you need any. X-tract and Emco as well! I don't believe that to be the solution, however. The countershaft provides too much movement and withoug redesigning it and the bearing carriers, It don't think you can stop the flex. Really not that many people could ever use them let alone those that need them actually spend the money.
Good luck.
12-11-2004, 11:48 AM
#12
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Originally Posted by IcemanG17
a "drifting" 928.....would be cool to see,
http://www.rieseler-online.de/timo/D...llenge2003.htm
Some others shots:
http://www.brautigam.de/racing/driftchallenge2003/
12-12-2004, 02:21 AM
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Hey Jim what are you talkin about I've been checking out this drifting thing pretty hard, and I haven't seen any porsche's out there. If you've see anything please tell me where, I gotta see it.
