Tough Overdrives-Do you have one?

The price of gas is nuts! Is anyone running an automatic overdrive that takes a beating in a heavy car? I've heard a lot of guys say a 700R4 won't take 450+ hp if you beat on them, but I'm sure if they can be modified to take more abuse, someone would know. I have a 57 Ford with 10" cheater slicks so weight is an issue. Thanks.

 

go the phoenix transmissions in weatherford texas ( on line) and he has the deal for you up to 1000 hp in 700r4 and aod ford as well as others we have purchased three 700/s and one aod from him they have worked great

 

if im right about whos car this is, youre running a 383 sbc so hence the 700R4 in a ford being easier than aod.

anything can be modded to take more abuse, and the 700R4 is no exception. ppl always talk trash about the 200R4 being junk...while to a degree this may be true...but they sure didn't have a problem when the buick engineers mated them to the intercooled 86/87 3.8 grand nationals...i have see 10 sec GNs with modded 200Rs behind them, so in essence, anything is possible.

if money isnt an object...try looking up gear vendors. its a bolt on o/d so you can keep your HD TH350/400 and actually can be set up to split every gear making a 6 spd with 6th as like .75 or something similar od...supposedly keeps your gas prices down and your car in the powerband for better 1/4s...never had one, never had the money for one lol...

 

I need to do a tech write up on what I did, but here the short rundown.

I'm running a very high horse stroker motor in my '58 Chevy street truck. With wicked low gears. I can seriously tear people up on the street. But forget getting on the highway even for an intersection hop cause I have to rap it out huge.
What are my options......regear and loose the street fighter advantage not a chance. Continue to smoke TH350's, doesn't sound so great. Or run a 700r4 or 4L80, maybe the 4L80 if it weren't for the cost. Gear Venders, too pricey.
Heres what I did. I already had a way beefy TH400 that will handle the ponies but ****s for anything over 55mph for any duration. I went with the gearvendors approach, but did my own. I took a mid '70's Ford 3 speed ****** that had the AUX overdrive on the back of it. I rebuilt that unit, and fabbed adapter plates to mount the AUX O/D unit to the back of my TH400. Then I tracked down a Cadillac TH400 for the tailshaft, they are way longer. I then had the caddy tailshaft respined to fit the Ford AUX O/D box. The long and short of it, I now have 6 forward gears, as I can now gear split. My effective highway ratio is now substantially higher with a 22% O/D.

Added benefit, you have to have the unit disengaged to use reverse. So as long as I pull into a spot, its kinda like an anti theft device. Even if they get it running and in reverse odds are against them figueing out how to get it to actually backup.

 

How bout a 4L80E? 'spensive ****ers but tough as nails.

 

A point of interest here for the SBC guys....

If you O/Drive your sbc car /or increase tire height and get the cruise range RPM down to say 2000RPM you will most likely LOSE gas mileage....it will breathe better and achieve better mileage above 2500-to 2800 RPM.

 

Definately, but you can run the 4L80 and not need the computer. You're limited to the early '90s Chevy 3500 C/K trucks and vans for them though.
4L80E has the E for electronically controlled shifts or '93 and up.
I've heard of them in some 2500's but do not know what build dates that this happened as most got the 4L60's

If anyone has better facts please chime in.

EDIT: also on the 4L80E's can easily be banged up if they aren't set up right. As in you'll start to slam shifts and studder start. Not good stuff.

 

GM still uses the 4L80E in big non-deisel trucks and vans. Stand alone computers are available to make them function. Thes computers also let ya tune the trans where you want it. You can change shift point, shift firmness, converter lock-out, etc. 'Spensive, but cool.

 

A TH200-R4 is a stronger trans once built up than a TH700-R4. It has fewer problem areas and a fully built one will take 1200hp turbocharged buicks running 8's at 3500lbs!

Art Carr makes killer ones.

 

Choprods has a good point.

My 88 Mustang GT with 5.0 liter & 5 speed got better mileage on a long cross country trip running 4th gear instead of 5th.
Running 70-75 mph the long and sometimes subtle desert upgrades will drag the vacuum down too low in 5th.

Put a vacuum gauge in the car and pay attention to what it's telling you.

 

I don't need overdrive, because I have 2.75 gears, and a switch pitch converter in the TH400. Works great for driving around, and trips too, although having 700 ft lbs torque to get the thing moving off the line is a big help.

on the vacuum thing...if the engine is making a lot of vacuum, then it is not making power efficiently, because most of the power is being used to overcome engine friction. For maximum economy you want the engine spinning low rpm and have the throttle open some. I did the experiments in college on the dyno, while building our high mileage car. But this does require a short duration cam, so the engine is working well at low rpm.

 

I don't want to hijack this post, but am in the middle of deciding what cam to put in my car, and your post got my attention. I'm using a Mopar 440/TF727, 27" tires, and 2:48 gears. Should I keep the duration pretty tame? How low? Thanks in advance for any help.

 

hmmmm...I'm running a mild blown big block, cam has about 230 degrees at .050 lift. The converter will stall at 2000 or 3000 at the flip of a switch. At 75mph I'm turning 2500 rpm.

With the gears you have, and no blower, it'll be a slug off the line, but still you need to match the cam and converter. You probably won't want more than 2000 rpm stall, so keep the cam to perhaps 220 @ .050 or less. Probably be worth talking to a cam company.

 

I don't think you will actually gain that much in fuel economy, your engine will just be happier and live longer. It will take a ****load of gas at a 1-2 mpg increase in economy to offset a $1500+ ****** swap.

 

And don't forget they have a dual bellhousing pattern, both Chevy and BOP...

I like the TH200R4 a lot.... it's also the same size as the TH350 making that swap really easy...

 

interesting comments on a wide variety of ******s

 

What O/D unit, R-10 or R-11. I could see the R-11 from the B.W. T85 ****** holding up but the R-10 wouldn't

 

You guys definately have some good points. I'm planning on a blower and some better heads soon so that Pheonix Transmissions sounds interesting. I'll look into that TH200-r4 also. I'm glad some guys that have been running them gave their opinions. There are alot of racers I know that insist the overdrives won't hold up, it's good to read otherwise.You just can't believe everything you read in the speed shop catalogs these days, you know? InDaShop, that combination of yours is just plain impressive. Thanks.

 

Hummmm, this is were I get them confused. The R-10 has the long tail shaft, correct? And the R-11 is the short one. I am using the short tailshaft one.

No, I'm just cheap and prefer to spend money on other ****. And this old racer I know from Kansas City gave me the idea. Then my cousin who builds adapter plates to mate NP203-NP205 transfer cases to make doublers for offroaders helped with the plates. Then resplineing a shaft.
I'm in for under $1g for my whole setup, built to the hilt 400, resplining the shaft was $180, and my time on the mill carving some aluminum. Watch for a tech thread. I really need to take pics, and show how I did it.
Its definately not rocket science.

 

In da shop, You definitly need to help your HAMB brothers out and do a tech post on how you did this conversion. The price of gas is NOT going down and having an OD trans that can take some torque is most welsome.


Frank

 

I run a 700R4 behind my 454, with about 450 hp and probably around 500 ft-lb torque. I broke one 700R4, bought second one from Phoenix trans and it's held up so far. Have a higher stall converter with lock-up still. If I did the car over I would spend the money for the 4L80E. Because I still fear the 700R4 is not really up to the strength I desire. The cost of two 700R4's kind of equals the cost of one 4L80E.

BTW, my 454 also broke two turbo350's when i was drag racing it, the intermediate sprags. Even though they were supposed to be the good hardened ones. My feeling is that Turbo350's are not strong enough for a strong big block. I switched to a PG and had no problems. Engine is same in my 38 except for smaller carb now and more closed exhaust. I consider the 700R4 about similar strength to the Turbo350, that's why above I still fear the 700R4 strength and durability.
I am interested to get some of the trans guys opinions, Crosley or Shifts what do you say?

 

the guts in a 700 are pretty much the same size as the 350, so you're right about them being the same strength.

also the 4L80E is mostly a TH400. I've never broken a 400 with my blown big block, but I do have to work on it now and again....but at least it's relatively cheap and easy to work on.

 

InDaShop...the an***heft thing is so true and funny. When I first wired up the fact od on my Merc, I must have done it wrong and it didnt disengage @ lower speeds, so when I parked...I was in OD. Well...one cruise nite, I pull in to a spot head in, go up till my tires hit the little cement stopper, and shut it off. What a surprise when I went to leave. Oops....I ended up having to jolt the car forward, up halfway onto the median to yank the OD cable and disengage it, then roll backward...what a fool I felt like. Almost had to get a running car towed out of a parking spot lol.....

Back to the matter at hand, sorry for the O/T....

 

The 4L80E is a pretty tough trans. There are a few standalone aftermarket controlers for them on the market these days too. All the adjustments of a shift kit by setting some controls on the box. Not traditional, or cheap, by a longshot, but very durable.

I also have a (top secret) overdrive type contraption in the works. I'll post about it when I get it finished...

 

Is a manual swap out of the question? When upgraded with Viper spec parts, the T56 6 speed is about as tough as they get, and both 5th and 6th are overdrive gears, plus they're realitivly easy to find in junkyards, and the LT1 Camero/firebird units have the standard Chevy bellhousing.

The T5 5 speed is even easier to find and much cheaper, but to upgrade it to T56 strength costs almost as much as a built T56, so it's kind of a bust.

 

Not sure, the Chevy R10 is short, on a ford they may have been long. I had a T85N from a 67 pickup and it was huge, bolt on rear yoke too. Borg Warner made almost all of them and I think there might even be R8-9 units from old 6 banger ramblers or something. They almost all use the same solenoids and other parts.

 

700 ****** is easy to break if you try...input shafts , out put shafts , planetary units, the aluminum input drum, drive shell