Hello, i was just wondering how much power a 700R4 (With a B+M Shift Kit) cna handle? I got a 383 motor on the stand (See signature) that puts out approx 500 HP and 525 Lb Ft (Add 150 on each side for a cheater shot now and then). Is there anyway my 700R4 and 10 Bolt can handle it even after i switch to a 3.73 gear? Ive considered putting in a Gear Vendors gear splitter unit as well. Am i better off switching to a TH400 and a 12 bolt?

Thanks for any info, Mike

 

Your tranny will probably go BOOM. You can help the situation with cooling which, I'm told, is the main reason for failure. I'm sure someone will post with a 700 that has run deep in the tens for years, but I think that would be the exeption, not the rule. I 've always heard the built 700's are good to about 450 horse but it depends. Those pro tour guys run tires that don't hook, so there 700's live longer, but if your car hooks up the 700 is doomed for sure

 

Yeah i suspected that, its gonna more of a Auto-cross/street car that is built for handling and lots of high end speed. Ive got a remote Trans cooler with its own fan that is supposed to drop the running temp 100 degrees on the list. Im only running P275ZR17 Rear rubber so the likleyhood of me hooking the car on a WOT dead stop launch is next to none. Alot of the dragsters around here run 700R4s for the lockup and they run dual coolers and a fairly thin ATF so the converter slips before any metal gives way but i didnt know what would happen in a street car.

 

You must have quite a cam in there for 500hp. If you haven't dynoed it then you maybe over estimating the horsepower. If you are making that kind of horse power and want a steet car thats kind of a contradiction. I doubt you can run power brakes at idle with the cam to make that kind of horse power. So my guess would be if you built that or bought it off somebody that has never had it dynoed, you maybe over estimating the hp rating. A 500hp engine is not friendly with gas for street purposes. And yes, the 700 is a little sketchy behind that kind of power. But if you don't plan on putting a set of slicks on it and hitting the strip, the 700 could handle 2000hp. Its all in how you use and abuse the tranny and rear. The ten bolt is not a strong rear end no matter what you put in it. You can use all the best parts, but the ring gear is so small and weak that it will fail with high hp and alot of traction.

 

Get a pro-built tranny and it will last. The 10-bolt will also, depending on how you hook it up. Drag radials will be ok.

There are lots of guys on here running built 700r4's with stock rears making power with no problems, myself included.

 

"the 700 could handle 2000hp." on drugs maybe! When setup right they can handle up to about 625 HP, after that.......

 

If it is going to produce that much power(FYI, I think a 150hp shot of N02 will give you around 300 of torque)--like he said above it's not really a street engine. Maybe street-strip or something. Obviously don't care about mileage. Why not run a th400/th350 and ford 9 inch/12 bolt chevy rear. That much power requires the rest of the drivetrain to be strong. I have no doubt Pro-Built can build a great 700r4, but if you don't need overdrive....

 

I'm talking about 2000 hp from stop sign to stop sign....not on the drag strip.....how stupid do you think I am. If you have a pro streeter but have all kinds of horsepower in your blown 502 but never race it and only have it for show, the 700 would handle that. Plus I have seen it done. But no, of course it won't handle 2000hp on the track or hammering the throttle all the time, and abusing the hell out of it. The saying was only for example purposes.

 

The motor is loosley based on what Hot Rod did with the Vortech 383 crate motor in their March 2002 issue. Specs are:

Torquer heads, 2.02 Intakes/1.6 Exhausts
SRP Forged Aluminum Pistons for 9.7:1 Comp Ratio (.030 Over)
Forged 3.75" Stroke (400 SB) with 350 Mains (383 CID)
Forged Aluminum Rods, 1.6:1 Ratio Roller tip Rockers
Edelbrock RPM AirGap Intake and 750CFM Carter AFB
Custom Grind cam, 250/253 Duration at .050, .554/.560 Lift

This is the exact same specs as the engine i built for my friends 81 Z-28, that motor idles a little sloppy but acceptable with about 11 inches of vaccum at 900 RPM. This motor was tested on the local engine dyno at 485 HP@6000, and 505 Lb Ft @4250.

This test was run with open headers so id imagine only 420 ish HP and 430 Lb Ft with street exhaust.

The lockup will be kept because of the 3.73 (or 4.10 Gear if i can find speedo gears). The 3.73 will force the tranny to run faster for a given speed and its a law of physics that as mechanical part rotate faster they can transmit more power, so i ll use the lockup to save gas and also (I hope) the trannsmission.

Another question now: Since the 7.5 inch 10 Bolt is obviously not up to the task, what can i easily put in? Is it possible to modify and move all the suspension and drive points from the little 10 to a early 10 bolt or a 12 bolt? What will the 9 bolt rears hold?

PS. It uses 91 Octane with Corn Ethanol and one bottle of octane booster per tank