I am re-doing my 68 SS I have a Shafiroff 540 dynoed at 714 hp @ 6500 & 655 lb ft. I want to run an overdrive auto with a manual valve body. I don't know who to trust or which tranny to run(700R4 4L80E...) I have been out of hot rodding for a while & got the bug again real bad. I also want to know if anyone makes a posi unit that will hold up in my 12 bolt. If not I might get a dana 60 or 9 inch. Or even spool it

Definitely a 4L80E over ANY 700R4. Its not even worth a technical analysis, the 700 isn't a reliable trans even when paired with much less power. I know of no 600+ torque applications that have successfully run a 700R4. The 700 doesn't take well to larger sized torque, or to high rpm either. The 4L80E is a descendent of the TH400 and can be built to hold much more power than you have.

Others will have to tell you about the posi, but at that power level if you are pounding on it I would reccomend a spool in the 12 bolt.

Thomas

I run a powertrax in my 12-bolt. 5 years and 450+ passes on it.

You might want to look into a 200-4r with all billet internals. The buick GN guys run them, and I know for a fact that if properly built, they will handle a lot of torque. Several 9 sec cars run them.
Steve

T400 & Gear Vendors possibly.

My vote would be a properly built 4L80E (you get a higher stall converter to lock under WOT, its just you need a $$$ converter), where you can use a computer to set shift points, firmness, blah blah, and just make sure the converter is good.
You can also get "de-computerized" 4L80E's with full manual valvebodies. If you are using a non-stock shifter (I expect you will be) this would be the cheapest option.
I have a TH400 and GV. Its OK but the integration is not there, the shift in time for OD seems to vary too much if you ever needed to go into OD while racing (I know it sounds silly to some, but people do it sucessfully).
A 4L80E, properly built and not abused would be your optimal pick, I would think. The GV installation was not as easy as it could have been, I had to have the floor cut to fit it and a custom crossmember made.
I had the GV in place but couldn't get the pinion angle right, so I had a shop take a look at it and they ended up cutting a 1'*1" hole in my floor that they raised up 1/4"... I was't thrilled with the method, but you can't tell its been done unless you look under the car,

hth

Matt

I think that a well built 200-4R is a much better choice than the bulkier and much heavier, (i hear about 240 pounds) 4L80E. I also think you will have to do a lot of cutting on the transmission tunnel to get a 4L80E in there.

No expert here but considering your looking for an oeverdrive leads me to believe this is a street car. I bet you'll be spending some serious coin getting an overdrive slushbox to hold up in that car if it's going to be used hard. You could row your own gears with a TKO600 for much less money, no high dollar converter to heat up and destroy either.

Check Tom's Differentials (http://www.tomsdifferentials.com) for a lot of performance Eaton Posi Units. I believe they have 5 or 6 different ones for a 12 bolt in both 30 and 33 spline. I'm sure they can make a recommendation for your power level.

The only people I know who have had success with 700R4s are pushing a lot less weight than you will, or at less torque. Art Carr (http://www.artcarr.com) has some 4L80Es that would stand up to your power, but quite pricey and require a core charge.

When previously faced with a similar dilemna, I opted out for the TH400. By the time I spent all the dollars on a 4 speed automatic that could handle the torque, I was in the realm of a clutchless G-Force (http://www.g-forcetransmissions.com/tran_g101.asp) or Jerico.

TH-400 and Gear Vendor. That is what I have in my Chevelle...can handle 1000 HP and a blast to drive smile.gif

I have a 4L80E in my 66 Chevelle. Stock tranny,Trans-go full manual valve body kit, 9 1/2" 2800 stall Precision Industries billet single disc lock-up converter,Hurst ratchet shifter. It works great. I put one small dent in tunnel to clear cooler line fitting, moved stock rear mount back, drilled new holes. That's it. It is expensive & it's heavy. Suppose to be good for 900 HP. That covers most of us.

Originally posted by Bomber '67:
Definitely a 4L80E over ANY 700R4. Its not even worth a technical analysis, the 700 isn't a reliable trans even when paired with much less power. I know of no 600+ torque applications that have successfully run a 700R4. The 700 doesn't take well to larger sized torque, or to high rpm either. The 4L80E is a descendent of the TH400 and can be built to hold much more power than you have.

Others will have to tell you about the posi, but at that power level if you are pounding on it I would reccomend a spool in the 12 bolt.

Thomas I have ran 2 bowtie overdrive 700R4's in my chevelle and my wifes camaro. I run High 11's and was recently dyno'd at 472rwhp and 670tq with a spike to 730 when the converter flashed. I have ~500 qtr mile passes on it. The camaro runs low 11's with over 1000 passes on it.

Also, the camaro has a brute force posi, again over 1000 passes and she runs wheels up on every launch and no issues. Spools are dangerous, I see so many cars get in real trouble at the track when there's traction issues. We've never been even slightly out of control in poor track conditions yet even slower cars have hit the wall! If you are going to run it on the street a spool in my opinion should never even be considered.

Lee

Originally posted by mph131:
I am re-doing my 68 SS I have a Shafiroff 540 dynoed at 714 hp @ 6500 & 655 lb ft. I want to run an overdrive auto with a manual valve body. I don't know who to trust or which tranny to run(700R4 4L80E...) I have been out of hot rodding for a while & got the bug again real bad. I also want to know if anyone makes a posi unit that will hold up in my 12 bolt. If not I might get a dana 60 or 9 inch. Or even spool it That engine combo makes so much torque,why do you even need an overdrive trans? What rear gear were you considering?

I was thinking of a 3.73 I want to be able to cruise on the highway. Do you think I can use a 3.55 and a turbo 400?

I run a 3.42 gear a TH400 and a 4400 9" converter. 3200 RPM at 65 with a 27" rear tire diameter (295/50/15).

Still works pretty good at the strip.

The guy who did my cam swap runs a 4L80E behind a procharged mopar engine making 1200+ ft-lbs of torque on a conservative dyno.
He uses one of the "de-electricked" versions. Its stuffed up in his car with a big kevlar tranny jacket, the car has a full stock interior + cage and does regular 160+ mph 1/4 runs.
A guy who hangs at the local car show has a 70 SS with a ram jet 502 and 4L80E that he said required nothing fancy to fit it in there.
My gear vendors took quite a bit of work to get it to fit in right. If I were to do it again, I would do a 4L80E, but that is me.
I won't ever break the gear vendors, and coupled with a TH400 that is easy to rebuild if it ever breaks, its a stout combo.
Its cheaper than a beefed and properly convertered electronic 4L80E, but probably not all that much cheaper, if it is cheaper, than the no-electronics 4L80E.

Matt

Originally posted by MadMarv:
The guy who did my cam swap runs a 4L80E behind a procharged mopar engine making 1200+ ft-lbs of torque on a conservative dyno.
He uses one of the "de-electricked" versions. Its stuffed up in his car with a big kevlar tranny jacket, the car has a full stock interior + cage and does regular 160+ mph 1/4 runs.
A guy who hangs at the local car show has a 70 SS with a ram jet 502 and 4L80E that he said required nothing fancy to fit it in there.
My gear vendors took quite a bit of work to get it to fit in right. If I were to do it again, I would do a 4L80E, but that is me.
I won't ever break the gear vendors, and coupled with a TH400 that is easy to rebuild if it ever breaks, its a stout combo.
Its cheaper than a beefed and properly convertered electronic 4L80E, but probably not all that much cheaper, if it is cheaper, than the no-electronics 4L80E.

Matt Would that be Scott at SDCE?

Jody

Please consider a Real Art Carr 200 tranny built by Art Carr that's built to the level you want..

Bruce, (WE4), may be able to help too?

I have faithfully tried to keep the post about trying to make a 700 live alive and it's just not happening... Yet anyway???

And I went so far as to get a price quote a while back from Art b/c of my 496 and me being worried about what will hold it after I break my M-20...

pdq67

Lee, keep in mind that with your same converter that mph131's 655 flywheel torque will be multiplied easily beyond the 670 rwtq you achieved, and that it would spike into the 800's.

Lee, I'll have to respect what you have done - but at the same time I'll say that you are on a small island of guys who have a 700R4 alive after 500 passes in your Chevelle and 1,000 passes in your Camaro. I have never seen a 700R4 that didn't need a refreshening after a regular season of ~ 250+ passes. I've also never seen a 700R4 with any reliability in a middle heavyweight Chevelle that was quicker than mid 11's. I run a Bruce Toelle Billet 200 4R in my '65, and I do know that his 200 4R's are in some 9 second cars. I know of exactly zero 9 second cars with any type of 700R4.

The beauty of a 4L80E is that virtually ANY shop can set it up for a high power application. I might have mentioned a billet 200 4r, but that was not what he was choosing between. Besides, a fully billet 200 4R is more money than a non-computer 4L80E - and there are probably only a half dozen shops that can properly setup a 200 4R. Your success with a Bowtie Overdrives 700R4 goes beyond anything that company would promote for its product.

Spools are safer on a drag car than any regular posi outside of a locker, and the reduction in differential rotating mass contibutes to lower e.t's. Spools make a drag car feel like it is on rails compared to a posi, because a posi in a high powered application has a hard time laying down even power to both rear wheels for the entire length of the track. I've driven spools on the street on a limited basis, definitely not for everyday driving, and they are fine unless you do something stupid.

Thomas

I will echo what everyone else has recommended. Either go with a built up 2004R (I suggest Bruce @ Performance Transmissions) or a 4L80E.

A TH400/Gear Vendor combo will also work but you won't get the added bonus of a lockup converter and in the end it will probably cost just as much if not more money than either of the above two options. However, it would be neat to run a TH400 Switch Pitch with a GV unit behind it...

You won't need a "brain box" with the 2004R if that plays into your decision at all. Personally, I would go for the 4L80E just for the electronic controller because it makes it VERY easy to define transmission behavior-- no futzing around in the valve body or with the TV cable and governor. Just plug the laptop in and fix what you don't like.

Oh, and MadMarv... when you say the guy who did your cam swap with the Procharged Mopar with the 4L80... you don't mean Scott Dickenson of SDCE, do you? Sure sounds like him. Tell him I said hi next time you see him. He's helped me with all my blower stuff, designed my cam, made my intake, etc. I really want to meet the guy face to face one day, he's a kick to talk to over the phone. Super nice and knowledgeable guy!

Troy

Yeah it was scott. I just don't use his name on the boards because of a minor tiff. He knows his stuff though.

Matt

Thanks for all the replies. I was curious about a cross member for a 4L80E? I think that's what I'll wind uo using with a full manual valve body. I also plan on using Torque Tech's full 3.5
inch exhaust. Do I need a custom crossmember that will leave room for the pipes? I have access to a welder plasma cutter and steel if needed.

Before you make a descision Call Bruce at performance transmission and have a talk with him about the 2004r vs. the heavy 4L80E.
http://www.ptsnctb.com/

I run a 200 4R behind my BBc, I am no where near your power level, I know the 200 4R can be built to handle that much power, but for how long??????

If you want some reliability, get a built THM400 and put a Gear Vendors unit on it. You will be happier in the long run!

Another option if you'd be willing to put brand F parts in a Chevy.

http://www.ckperformance.com/ford_aod.html

http://www.ckperformance.com/

Give Chris a call he's put a few AOD's in GN's.

I have a close friend that has a '66 Bel Air with a Shafiroff 540, T-400, and a 9" Ford with 3.50 gears and a locker. It has an ATI converter that flashes to just under 3800. It also has 295x65 Drag Radials which are over 29" tall.
It drives GREAT on the street, cruises decently, and is just awesome at full throttle. And the NX 300hp system makes it a real animal.
Nice thing is it's about as durable as an anvil.

I believe with as much torque as that 540 makes, just use a T-400, 3.42-3.55 gears, a tall tire, and a real good converter. It'll cruise great and you can spend the money you saved on other go-fast parts.

Randy

That was the point I was trying to make,also. With an engine making that much torque,a 3.08 cog would probably work great. Remember,the more torque & hp,the less gear you need.

Doesn't that burn up the tranny? Having the stall speed so much higher than cruising RPM?

I have a 2500-3000 stall and 4.11's. I want to swap to a 3.00 or 3.10 gear in the Currie 9" instead of a big dollar tranny since the TH350 works so damn good. Granted I am only making about 550lb-ft, but more will come pretty easily with my mild 454 combo.