I have always believed that a 700r4 beefed up can handle some serious power(500lbs of torque and up) but now I just don't know. My beefed up tranny that cost me a good amounth of money just gave out behind a 454BBC. I was told by a tranny shop that my best bet would be a 400 with a 10% lower first gear and 6% lower second gear which they can build for me. I am thinking if I should go with the 400 or just rebuild the 700r4 , I kind of like the overdrive. Altough I can go with overdrive for the 400 from Gear Vendors. Any replies would be greatly appreciated .

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383 86 Camaro Z28
10.5:1compression Dart Pro 1 Aluminum heads 215cc>2.05/1.60 valves,400 steel crank,cam specs:224/234 at 050 525/525 lift,3500 stall converter,shift kit,3.42 gears,770 Holley Avenger,Victor Jr. Intake,true dual exh,Hooker headers with 40 series Flowmasters,MSD Coil and Module.ALSO SECOND GEN Z28---mods:454 BBC,.546 max lift(doug herbert cam ) 750 Holley vac sec. ,Edelbrock Performer manifold,Holley electric fuel pump,Hooker headers,Flowmaster mufflers,beefed up 700r4 tranny, 3.90 gears, powertrax unit, B&M console shifter.

 

As long as you get the tranny rebuilt with heavy duty internals it can handle the power. I believe I read somewhere that some people have 700r4's behind BBC..

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'86 IROC
T-TOPS, TINTED WINDOWS, BRAKE LIGHT BLACKOUTS
GM GOODWRENCH 350
EDELBROCK TES HEADERS
FLOWMASTER, NO CAT
EDELBROCK 600CFM CARB.
KN AIRFILTER
ACCEL HEI DISTRIBUTOR
160* Stat
2:73 GEARS
Rebuilt 700R4, with manual valve body
B&M Megashifter, 5" Autometer Tach w/shift lite
Soon to be installed
3:73 Richmond Gears and 3" Hooker Aero Chamber
Corvette Servo & .500 boost valve
15.61@ 95.2mph G-Teched, 1-2 shift slippage, and just replaced a burnt plug wire
"There is nothing more addicting than speed"

 

For driving around on the street it'll be fine but I doubt it will last long at the race track. I didn't like the gear ratio of a 700R4 or the fact of the extra weight and gears I don't need.

I currently run a TH350 tranny and want to go to a powerglide. For what it would cost to bullet proof a 700R4 I could probably build 3 TH350's. The reason I didn't go with a TH400 is that it's bigger and heavier.

GM always put TH400's behind big blocks especially the 454 but then they were also supposed to last the life of the vehicle.

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Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z SuperPro ET Bracket Race Car
461 naturally aspirated Big Block

Best ET on a time slip: 11.242 altitude corrected to 10.89
Best MPH on a time slip: 121.52 altitude corrected to 125.89
Altitude corrected rear wheel HP: 497.9
Best 60 foot: 1.546

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

I guess I want to have my cake and eat it to. I want to be able to take my car to the track and also drive it on the highway. I may be asking for to much. Am I?

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383 86 Camaro Z28
10.5:1compression Dart Pro 1 Aluminum heads 215cc>2.05/1.60 valves,400 steel crank,cam specs:224/234 at 050 525/525 lift,3500 stall converter,shift kit,3.42 gears,770 Holley Avenger,Victor Jr. Intake,true dual exh,Hooker headers with 40 series Flowmasters,MSD Coil and Module.ALSO SECOND GEN Z28---mods:454 BBC,.546 max lift(doug herbert cam ) 750 Holley vac sec. ,Edelbrock Performer manifold,Holley electric fuel pump,Hooker headers,Flowmaster mufflers,beefed up 700r4 tranny, 3.90 gears, powertrax unit, B&M console shifter.

 

Talk to this guy= www.pro-built.net

He can build you a 700R4 that can handle 600hp with a 1 year warranty.

 

If you want to keep overdrive behind a big block, your best bet would be a 4L80e. You need the electronic controller for it though...

I don't personally trust a 700, nor a 350 for that matter, for long life behind a big block... I don't care how 'well built' it is, it's like defying the laws of physics. The only reason drag racers put 350's behind big blocks is for less drivetrain losses.

 

well as far as transmissions go maybe we've gotten lucky, but l've got a 90 IROC with a stock 700R4 trans, it puts out on juice over 400 HP, and has 71,000 on the clock, it still shifts as firm as when the day l bought it, my brother's got a 87 berlinetta with a stock 700R4 trans and its got a ZZ4 motor in it, and it shifts great still, now obviously this is a huge difference in HP and torque when compared to a BBC, but thats been our experience with 700R4s.

my brother's also got a 71 monte carlo with a 468 BBC, it puts out over 500 HP and runs with a stock TH350 trans with a shift kit and 3,000 RPM stall. still shifts really firm and has run smooth, run after run.

 

"My beefed up tranny that cost me a good amounth of money just gave out behind a 454BBC."

Out of curiousity, what "gave out"?

How was it built?

 

They wont hold up to power.
I tried 2 different built 700`s and both blew up.
I refuse to listen to any else that it will work, however id be more than happy to prove them wrong if they give me a trans to try to prove ME wrong.
My car only makes 300 RWHP and 410 RWTQ on motor....but on spray it makes 450 RWHP and OVER 700 RWTQ......I couldnt start the dyno low enough to get the highest figure.

The most recent trans lasted about 3 months, roughly 40 or 50 motor passes, roughly 20 nitrous passes, several 2 foot wheel stands, apx 5000 street miles driven EVERY DAY everywhere. Would go somewhere between 10.70 & 11.20 depending on the track and weather.
Ripped the crossmember out of the frame 2 times too.
First thing the trans did was in the middle of a nitrous pass it just went into a free rev....i had to put it in neutral and back in D to get it to go again.
From that point at random times the trans would just go into a free rev when i was accelerating, usually went into a free rev when i hit a bump and would go under its own power if i let out for a sec and let the revs come down....it wasnt slipping at all, I had a trans temp gauge hooked upto it and it NEVER heated up untill the day it blew up big time....it would run normall around 170 or lower all the time.
The day it blew up, I pulled off my street on the main road and got in the gas slightly because of traffic....I hit a bump and BLAMO!!! big bang clunk boom.
I was in overdrive and it did the same thing my last trans did....it felt like 2 gears were engaged in OD, kind of a binding feeling.
Then I put it in 1, then upshifted to D, had D for about 100 feet. So i stopped and put it in 2 and had it till i got around the corner. Then D was engaging and disengaging....then i only had 1st....then i had nothing excpet park and neutral.
Shut the car off for a minute and started it back up and had reverse, so I drove it home in reverse.
Now the trans is on my lawn.
Id really love to find a sure fire bullet proof (to a point) 700-R4 or atleast take it for a year or 2 before needing to be gone through.
The overdrive and 1st gear are great, but the drop between 1 & 2 suck.

 

On the cover of a recent Hot Rod magazine (September, or August?) is a red '65 Impala SS. It has a nice 454 in it, goes on the power tour, and runs 14's at Bandimere.

It has had a $600 rebuild TH700 in it for the last 3 years.

Some may not consider that "serious" horsepower, but it's at least respectable. The tranny has given him exactly zero problems, though.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4. 2.93 limited slip. Cat-back from '91 GTA, ZZ3 intake, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/'87 LB9 block, ZZ3 cam, ported World 305 heads, Hooker headers & y-pipe, 3" Catco cat & 3" cat-back, Spohn SFCs).
57 Bel Air, my 1st car. '66 396, 9.7 CR forged TRWs, Weiand Action+, Edelbrock 1901 Q-Jet (Holley 3310 on the way), GK 270 cam, Magnum rockers, Jacobs Omnipack, 1-3/4" Hedders & 3" Warlocks, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, MegaShifter, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Idles smooth @ 600 RPM in D. Best 15.02/95.06 @ 5800' Bandimere (corrected 13.93/102.4 @ sea level).

 

Transfixleo I spoke a bit to soon. My tranny was checked out and it did not give out like I had initially suspected. I feel kind of stupid really , it turns out the TV cable was not adjusted properly and I overreacted . A lesson learned. Now the tranny is working real good. I thanked the guy from the tranny shop cuz he could have lied about it and I could have paid some good money for another overhaul. Total cost 35.00 for the diagnosis and adjustment of the TV cable. After all this I am still nervous about really getting on it with this engine making over 500lbs of torque.

 

It's not the HP that will kill the tranny but the torque. A big block produces much more torque than a small block ever will. Add all that into a heavy car and it multiplies the chance of a failure.

 

If you are worried then a TransGo Reprogramming Kit is in order. Also, to save you $35 in the future print this out:

To adjust the TV Cable skip the book method and do this: Press the D button on the adjuster and loosen the cable setting. Now, have someone floor the gas pedal while you check to see if the throttle plate is open all the way. Usually they are off a little and will wiggle. Do whatever you have to do to get it open solid. Now, with the pedal still floored, press the D button and pull the cable casing (the black tube) back as hard as you can and release the button. You now have the engine, tranny and gas pedal all in sync at WOT. Mark the cable so if for some reason it gets moved you can know where to put it again. The problem with the 'self adjust method' is that it bends things and puts them permanently out of whack. It is also the full TV setting, which is theoretically what the GM method does.

 

This may sound dumb but should I pull the black tube back toward the firewall or the front of the car?

I usually push in the D button and get someone in the car to floor it and then let go. What does pulling this back do?

 

Pull it back towards the firewall.

------------------
'86 IROC
T-TOPS, TINTED WINDOWS, BRAKE LIGHT BLACKOUTS
GM GOODWRENCH 350
EDELBROCK TES HEADERS
FLOWMASTER, NO CAT
EDELBROCK 600CFM CARB.
KN AIRFILTER
ACCEL HEI DISTRIBUTOR
160* Stat
2:73 GEARS
Rebuilt 700R4, with manual valve body
B&M Megashifter, 5" Autometer Tach w/shift lite
Soon to be installed
3:73 Richmond Gears and 3" Hooker Aero Chamber
Corvette Servo & .500 boost valve
15.61@ 95.2mph G-Teched, 1-2 shift slippage, and just replaced a burnt plug wire
"There is nothing more addicting than speed"