Will a 700 live behind astout BBC?

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Will a 700 live behind astout BBC?

Postby pdq67 » Thu Feb 16, 2017 8:25 pm

Just how much hp/t will a built 700 auto tranny take behind a stout BBC??

I'm talking 496" to 540" BBC, 700 and more hp and whatever t that equates to!

Or should you just step up to one of the 4L80 type trannies instead and not worry about it?

Real slicks and geared to GO!! 3400 pound 1st Gen. Camaro car.

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Re: Will a 700 live behind astout BBC?

Postby 77cruiser » Fri Feb 17, 2017 9:43 pm

4L80 the 700 won't do it.
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Re: Will a 700 live behind astout BBC?

Postby F-BIRD'88 » Thu Feb 23, 2017 6:57 pm

Th400. A overdrive is near useless in a car with a radical hot rodded motor like that.
It does not really do you any good overall.

Such a cammed up motor wants to be running at about 3000 rpm at free way speed.

So a Th400 3 speed auto trans gets it done.

Won;t even get into the fact that such a powerfull motor will eat a th700r4
MANY times over. How may times are you going to rebuild/replace that eaten trans
before the $$$$ pain in the back pocket convinces you you're spending twice what ever you think you will save with overdrive.
This is a transmission that was designed to work behind a 300 to 340HP engine with about 370FT/lbs torque. It is a weak transmission for your

The early mid 60's B O P Switch Pitch torque converter th400's are very cool. Can be built on a Chevy th400 case
Now you got a cool HD hi perf high power capable trans that can take the BBC power.
And deliver impressive perf and efficiency.

With your Camaro and 3.31 gears and purpose, don't waste your time or money on a OD transmission.

Better to put some budget (67++CC chamber) aluminum heads on that 325" SBC to drop the compression ratio
and SUPERCHARGE it. Now you got 600-HP yet sips fuel when cruising (relative) cause when off the boost its still a relatively mild 325 CID engine. The car is lighter weight with the lil blown SBC. Even this combo does not need a OD trans to cruise nice and give you real neck strain when you hammer on it.
The Magnuson MP122 hh (Trick Flow or Edelbrock SBC KIT) lil blower is a bolt on.
Ya it will make that much power with high boost and intercooling.
Much better use of the money.

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Re: Will a 700 live behind astout BBC?

Postby pdq67 » Fri Feb 24, 2017 10:37 am

Back when I ordered my car in Oct., '66, I wanted the old 3-speed stick OD but GM quit selling them in something like '64 or '65 or so.

So had to settle for my M-20 Muncie.

And as far as an OD auto tranny, I would go with a built 2004R, (R4?), from the real Art Carr... But it will be pricey!! Art said one can be built to hold something like BBC 700Hp and the T that goes with it....

And I keep biting at Autogear and them not wanting to make a real 5-speed Muncie, He, He!! And they put up with me. I even said that I would help design it for free.....

Autogear's good people by me..................

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Re: Will a 700 live behind astout BBC?

Postby Speedbump » Fri Feb 24, 2017 11:15 am

I just went to a bunch of trouble to change my switch pitch TH-400 with DNE overdrive (my first idea) to a 4L80E built by Joel on Joy with a HD lock up converter and a TCI controller. The difference is astounding. So I completely disagree with F-Bird based on experience. Mine is a 505 CID BBC with a tunnel ram and a 240's @ .050 cam. The truck is SO much more fun to drive and the freeway cruise is great due to the lock-up converter. TCI gives you lots of options with the touch of a button on the console. It did cost a bunch for top notch stuff but I don't regret anything other than I wish I had thought of the 4L80 before the expensive TH-400 experiment. By the way, I have a killer switch/pitch chevy 400 with an A-1 converter and a DNE overdrive/custom shifter for sale if you want.
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Re: Will a 700 live behind astout BBC?

Postby F-BIRD'88 » Fri Feb 24, 2017 12:12 pm

When the "Wow I got a new tranny" physiological novelty wears off you will find that overall you spent a lot of money for nothing. The switch pitch th400 will out live you.
Cannot tell you any thing about a DNE2 except you rally don't need it.
You won't drive FAR enough often enough to pay for it.
Better to just get 2 different size rear car tires. Tall 29" 70 series for "cruising"
Short 26" stickies for Drag racing. This effectively changes the gear ratio for the purpose.
For pennies on the dollar.

Keep the M-20 and supercharge that 325" SBC.

The th700r4 is a dog of a transmission even when "built" with all the hop ups and premiere
hard parts... With mild 3.31:1 rear gears you just don't need overdrive.
The new GM th 80LE trans is a better trans than the th700r4/th60Le and GMPP does have a new series of high perf high stall torque converters for it. But the price of admission is huge.

You already have the right trans the manual m-20 4 speed.

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Re: Will a 700 live behind astout BBC?

Postby Speedbump » Fri Feb 24, 2017 6:48 pm

"When the "Wow I got a new tranny" physiological novelty wears off you will find that overall you spent a lot of money for nothing. The switch pitch th400 will out live you."

I'm offering real world experience which is, by nature, somewhat slanted but when is the last time YOU did this swap or built a quality street rod? Your opinion is based on what?

"You won't drive FAR enough often enough to pay for it."

If that was the major reason for buying speed parts, this forum wouldn't exist.
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Re: Will a 700 live behind astout BBC?

Postby lefty o » Fri Feb 24, 2017 7:36 pm

the Art Carr ( cpt, not the current art carr shop)2004R, is a very nice transmission that will shrug off your little 325.

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Re: Will a 700 live behind astout BBC?

Postby pdq67 » Sat Feb 25, 2017 3:42 am

I have installed 29.5" tall Firestone Town & Country mud and snows on my car as well as my stock D-70/14" 25.3" or so dia. Firestone Redlines. I did have to raise my coil-over, overload shocks up about 4.5" or so though for my M and S's...

The tall mud and snow tires would do 145 mph or so at speed! Been there, done that! Trooper Beale couldn't unhook from his radar tripod quick enough to catch me before I hit the south end of Macon, MO. Late for my car pool on the railroad back then. 20 or so miles at 145 back about the early summer of '67....

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Re: Will a 700 live behind astout BBC?

Postby F-BIRD'88 » Sun Feb 26, 2017 11:04 am

Then you know how effective a difference in rear tire diameter has on net gear
ratio and engine cruise rpm at typical hi-way speeds.

Thinking more of say a P265 70r15 or P255-70r15 Cooper Cobra
for rear "cruiser tires". Will also have pretty good overall traction than a short street radial as there is more tread length contact.

You don't want to adjust ride height with the shock absorbers.
You want to support the weight of the car with the springs
( a add on AIR SPRING is great for adjusting ride height and load
capacity ( stuff in the trunk).
The shocks are for dampening springs, not supporting the car weight.

You will also notice that the car rides a lot nice with the 70 series tires too.

Then use a short sticky street/drag tire for drag P235-60-15 (8.5x26x15)
Effective and a fraction of the price of overdrive.

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Re: Will a 700 live behind astout BBC?

Postby pdq67 » Sun Mar 05, 2017 1:30 am

What does a good B/W T-85, 3-speed stick OD sell for?

And who sells them?

And I am surprised that somebody through the years hasn't hung just the OD unit off the front of the rear end's pumpkin.

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Re: Will a 700 live behind astout BBC?

Postby pdq67 » Tue May 02, 2017 2:10 pm

pdq67 wrote:What does a good B/W T-85, 3-speed stick OD sell for?

And who sells them?

And I am surprised that somebody through the years hasn't hung just the OD unit off the front of the rear end's pumpkin.

pdq67


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