Trans/clutch options for 860hp Cobra?

[750hp]

I am preparing to fit my old Vortech supercharged motor from a previous Cobra. Back when I built the old car, I chose the easy option and fitted a bulletproof auto trans.

This time around, I want a 5 speed that will have reasonable manners on the street. Is it unrealistic to expect a TKO600 and McLeod twin plate clutch to live with 860hp/705tq on street tires?

If any "street" trans is on borrowed time, is it a better option to go straight to something like a GF5R and a lightweight flywheel and small double/triple plate clutch?

I'm willing to go straight to a dog gear trans if I must, but I'm interested in how hard a traction limited, lightweight street car can be on a street trans.

[marcocsx3121]

The clutch should be OK, since I'm running a McLeod twin in my Corvette at 798 hp at the wheels. While I can't comment on the TKO, I would assume that the "street" tires would act as a safety valve and blow off before much damage could be done to the drive line.

[patrickt]

Originally Posted by marcocsx3121

While I can't comment on the TKO, I would assume that the "street" tires would act as a safety valve and blow off before much damage could be done to the drive line.

If "x" hp/tq will break your street tires loose, then all you really need for a clutch is, say, "x" plus 20%, right? Right now, with my measly little 475HP, "weak sister" FE, if I'm just slowly going down the street, or parking lot, and I give it more than half throttle, my Yokohamas just break right loose and spin and my POS Centerforce clutch holds just fine. Sooooo, if I had an additional 300HP on my engine, why would the situation be any different?

[blykins]

I offer "prepped" TKO 600's with about 700-725 lb-ft capacity. I would go this route with a McLeod RST clutch kit. I put this very combination behind my big inch Boss 9 engines with around the same hp/tq ratings and much heavier cars.

[ERA Chas]

Originally Posted by patrickt

Right now, with my measly little 475HP, "weak sister" FE, ...

Where did you find 75 more HP??

[patrickt]

Originally Posted by ERA Chas

Where did you find 75 more HP??

It always had it... I just downplay my numbers.

[patrickt]

I remember having a conversation with the ERA gang about the size of the u-Joints, both on the drive shaft and the four on the ERA rear. The long and the short of it was that the rear drive shaft u-joint was smaller than the front because, if something went really, really wrong, you would prefer to have that one blow rather than the front -- 1310 verus 1330, if I recall.... So, putting in a "monster" clutch, when the tires break loose well below "moderate" clutch holding levels is like putting in a monster front u-joint on the drive shaft, while the rear u-joint is still a 1310. No?

[750hp]

Thanks for the input. Brent, please feel free to PM me if it's more appropriate to discuss details away from the forum, but I'm keen to hear your thoughts around cryo treatment and faceplating options and prices.

[blykins]

Faceplating is not necessary, but we do a lot of stuff to them. Price is $3299 for a "Pro" TKO 600.

What's done: Includes Sure Shift upgrade, bronze shift fork pads, cryogenically treated gears, includes re-shimming. The 1st-4th gears, sliders, and hubs are REM finished.

These are rated and dyno tested for about 770 lb-ft.

If you think you would need more than that, the Magnum T-56 starts at about 700 lb-ft capacity and the same processes can be applied to increase torque capacity. However, I'm not a Mag fan....just too expensive, too heavy, too big, too everything. Also, in a lot of applications, the midplate needs to be modified, especially when using a twin disc clutch kit. That adds about another $300-350 to the bill on top of everything else.

[scottj]

Originally Posted by patrickt

If "x" hp/tq will break your street tires loose, then all you really need for a clutch is, say, "x" plus 20%, right? Right now, with my measly little 475HP, "weak sister" FE, if I'm just slowly going down the street, or parking lot, and I give it more than half throttle, my Yokohamas just break right loose and spin and my POS Centerforce clutch holds just fine. Sooooo, if I had an additional 300HP on my engine, why would the situation be any different?

You don't say what gear, but if a top gear roll-on breaks the tires loose, then yes the POS Centerforce should still hold... in that situation.





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[paulmartin]

how can anyone handle 850hp in a cobra..?......
oh yeah its the guys who end up upside down in a ditch or in a tree

[750hp]

Paul, thanks for your constructive and insightful opinion. Your own post about your driving style might provide some indication about why you made a d!ckhead comment, but a little restraint can go a long way, regardless of power levels;

Quote:
Originally Posted by paulmartin
i get a lousy 6 -8 mpg , 347 stroker ,4x 50mm ida webers , 205 AFR heads , and i like to floor it.....TRYING TO FIND IMPROVEMENT