I've decided to take the plunge this winter and install a 700R4. I'm looking for recommendations from the forum about what manufacturers/models I should be looking at or avoiding and any other tips or tricks you might suggest. I see some fairly positive stuff about Bow Tie, but who else is worth looking at?

It is going into an '81 with the stock 2.87 rear end (at least for this year) and a mildly upgraded 350 that is probably putting out 325hp or so at the crank. I know that I will need a shortened drive shaft and a new cross member, stall convertor, shift lever gate/indicator, TV cable and carb bracket. Anything I'm forgetting?

The car only has street use and I have no plans for doing otherwise.

 

Dont know if he ships but try Ron at TRC trans in Chatsworth Ca. Noone has broken one of his 700rs..been a customer sinc ethe 80s.
Hes a racer himself, runs an honest biz. doesnt gouge and stands behind his work. Builds his own converters

 

You dont need the tv braket. It fits right where the 350 kickdown cable goes.
I will post more info later.
BTO crossmember is perfect.
Install a cooler.
Shftworks makes the shifter kit. Buy direct.

 

I thought you could get a short tail shaft so you didn't have to shorten the drive shaft?

 

In a lower power application I would recommend the th200r4 . Other than the different transmission crossmember it is a direct replacement. Better 1st gear ratio. It also uses less hp.

 

I ageee with the above, but I also think to leave it alone, a 287 rear ratio is basically it's own overdrive right there, and for a normal street car, it's the way to go, my '72 350 car had a 336 ratio and I felt necessary to go over drive here in Florida, where at 80 mph we shift into o/d do the math on the ratios....60% o/d vs 336 to 287 and type of driving/distances involved....

 

I agree, that without a rear gear change OD would be about worthless.

 

My 3.08 gear at 80 MPH is 3600 rpm , 80 mph is pretty normal on I-75 and I-71 these days in the Dayton / Cincinnati , 2.87 would still not be enough . I'm switching my 80 T-350 out for 4L70 and don't plan on changing the 3.08 gears at this point

 

I love the 700R4 conversion in my C3... if I had it to do over again, I would purchase the transmission from one of the many
vendors available to us on line... and do the install myself.

my locally built/installed R4 finally works OK, but the installation was crap, they used a truck case rather
than the car version, I've had many leaks, adjustments, and other repairs to complete after the "so called local expert" worked on the car,
that the whole conversion experience was awful...

At $2300.00 It was not an inexpensive modification, and I got screwed.. choose your transmission shop carefully would be my advice.
mardyn

 

Truck case is stronger, and a win.$2300 is not out of line.
That being said, leaks are not a good sign.
However, I did adjust the governor 3 times to get the shift where I liked it.
It goes with the territory.

 

I like the 3.08 with 700r.
I might tip a shade lower next time.

 

You do not want...or need....an overdrive automatic trans in a car with a 2.87 rear gear. You will not be able to leave the car in Drive range until you get past 40 mph. Even then, it may do some 'lurching' when you need to apply light throttle for going up hills or under mild acceleration which does not cause a downshift.

I'm at a loss for understanding what you think an O/D transmission will do for your car. As is, you get over 20 mpg on the highway and cruise in relative comfort...compared to other C3's with 3.36 or higher (numerically) rear gear. Leave the O/D tranny swaps to those who actually need it. You really don't.

 

I'm not terribly disappointed with the truck housing... but they require specific converter dust shield, what I got
was a hacked up stamped steel cover barely attached with incorrect hardware....

I expected more for my money than the poorly executed conversion that I've now been correcting for the past two years.

Don't get me wrong here... I love the 700R4 conversion in my C3, it makes the car much more user friendly as we've all
become very accustomed to the overdrive gear/RPM spread since inception.

mardyn

 

That sucks. Mine came with the proper cast alum cover the later trucks had. Very strong.

 

Depends on what the tune of your engine works out to be. I would be looking at the camshaft specs, this is what I did when I put a 200R4 in my '70. You need to have your top gear rpm in the usable range of the camshaft. I tried the 2004R with the existing 3.08 diff but found I was turning too low rpm at our highway speed (60 mph) and running off the bottom of the camshaft power range so I changed to a 3:55 diff ratio which is fine.
Interestingly though, I have a C4 that runs a 2.59 diff and that is behind a 700R4 and this works okay - the benefit of computer control and fuel injection.

 

It'll get him around 2,000 rpms at 80 MPH (assuming 27" tires) which puts it on par with a lot of modern vehicles. Not sure what's wrong with that.

DC

 

i'm in the same boat as Haggish, i have a 700r4 behind a strong 350 with 3.08 rear.
in O/D with torque converter locked up at 110km/h (70 mph), i was only about 100-150 rpm above the bottom of the cam range, makes it a bit sluggish for overtaking..
so thinking of going to a 3.36 rear to bump it up a couple of hundred further into the cams range.

 

My C3 has the factory 3.55 rear. I installed a 700R4 years ago (maybe 10 yrs by now), been running fine. With the 3.55, it's a good combo.

 

At this point, I’m not really after the 700r4 for the overdrive gear. I’m after it for the deeper first two gears. I want something that will make for a bit more fun off the line and stoplight to stoplight. I’ve done all of the engine mods that I want to at this point, so I was looking elsewhere for grunt. The 2.87 rear and 700r4 is the same as the factory set up for the ‘82, so I don’t think the engine will lug, though of course it won’t be in the peak of the power band at highway speeds.

The long term view is likely a new set of rear gears in the 3.55 area. I don’t want to change the rear gears first, because I don’t want to be revving at 3500 on the highway for a couple years while I save up the cash for a new transmission.

So...back to the 700R4 recommendations...

bg2bird, thanks for the hints, I think my 350c has a cooler already, but I guess I will need to run new lines. I hadn’t thought of that. I don’t know if I can use the existing cooler.

mardyn, I do have some local rebuilders around me, but was wary of using them because it was tough to know much about the quality of the work they were doing, I was already leaning towards one of the online vendors who seem to be doing a lot of this work and have a bit of an established reputation. What you are saying confirms my suspicions.

cusineartvette, I’ll call up TRC and see what they have to say, especially about shipping.

 

i’m not seeing that in any of the specs I’m looking at Len. It looks like neither the short nor the long tail shaft for the 700 makes for the same length as the 350. Maybe I’m missing something?