Porsche tranny ?

Sounds like Marty is thinking about an engine transplant?

Marty,   Call Mike at "Rancho"....   He's very knowledgeable on these transmissions and can give you the most accurate SWAG....

I believe this will provide the answers you seek.
http://rennsportsystems.com/le...ons-clutchessscluct/

Realistically, as much as you want to throw at it, Marty.

You've got that right - in terms of power and money.

I've seen a couple of 930's running 915 transaxles and pushing over 400hp and 350 ft. lbs. of torque and the 915 survived.  These were both road-course cars but they had "gentlemen drivers" who only moderately pushed them.  On the street, I'm sure they would survive for years.

Angela might be a better person to ask, but I think that the bearing structure/placement on a 915 can handle more torque than the gears can.  The usual failure mode for excessive power (over 500 hp, say) is stripped gear teeth.  The synchros hold up (for the most part, but they get burnt from overheating), the bearings hold up, but the gears get ripped apart.  One quickly learns, with a very high powered engine, NOT to do hole-shots (Blasting off the line in first) because the first gear is machined onto the mainshaft and cannot be replaced without replacing the shaft - a pretty expensive first gear, IYAM.

"Reving pretty high" is an interesting question, since the transaxle can usually handle spin speeds in excess of what the engine usually produces, but as the input shaft rpms increase it becomes harder for the synchro rings to do their line-up thing to transition from gear to gear, so the transition speed will slow down - especially as the transmission oil gets hot and thins out.  That's why the later 915 transaxles have external oil coolers and some have pumps to circulate the oil much faster to keep it cool.

So, the short answer is yes, they can handle input shaft speeds up to around 11,500 rpm, but not regularly.  24 hours of racing and reving to 8,500 rpm shift points (or more) and the 915 will essentially be toast and need a complete rebuild.  Same for the latest versions being run in GT3 cars (which can handle more than 700 hp).  Watch the Rolex 24 hours and see how many Porsches drop out due to transaxle problems towards the end of the race.

This help?

Yes, thanks.

What is the maximum wing velocity of an African Sparrow?

150 strokes per second...much slower than a Mexican Green Head Humming Bird ?

"150 strokes per second...much slower than a Mexican Green Head Humming Bird ?"  ...but slightly quicker than Pee Wee Herman.

I have several 915 based cars out there with 250-275 hp, and they're all holding up well. They see "spirited" driving, but don't get beat on too badly.

We have 350ish hp going through a 915 with added pump and cooler and it DOES get the snot beat out of it (track only car, 8500 redline) and it has held up for 5+ years...

While sitting in a movie theater....

And I thought "Porsche tranny" was going to feature a photo of Vince and Gerd entwined and almost naked......in a Speedster!

Between Ron and Danny I've lost interest in breakfast!