700r4 good with 3.73 rear gears ???

If you have MCSS why step back to 700-r4? It's heavier & has heavier parts to try to rotate so it soaks up a little more power and fuel to run, has too low of a first gear for a powerful motor in a light gbody, has a less than ideal gear change from 1st to 2nd and does not have as tall of an overdrive. Plus you have to have your drive shaft cut to make the conversion work and the MCSS already came with the 200-4r. On top of that they cost the same to build up to withstand the same power.

I know back in the day the garden variety 700-r4 was a little stronger than the garden variety 200-4r and many shops didn't know how to build a performance 200-4r but sheesh we have had the internet a long time now seems like the info should have made its way around.

PS. Pat have you ever got a time slip on a bat out of hell yet?

I had a 700R4 in my car with 3.73's works great!! But I now have a 5 speed which is better

I think 3.73 with an overdrive are about the max you would want for a car that is driven daily at highway speed.

When it comes to the gear change from 1st to 2nd, its not as dramatic as people say it is. People are relying on the "numbers" without having the experience of driving one. The first gear of the 700r4 easily compensates for the minor gear drop from 1st to 2nd compared to the tighter gear ratio from 1st to 2nd in the 200-4r. It's mostly a matter of opinion, when I calculated the costs of building either one up to par, the 700r4 was $600 cheaper than the 700r4. Nowadays, the parts for the 700r4 are parts coming from the 4L60. Over half the parts that went in to my trans were labeled 4L60 and the parts were much cheaper compared to the same parts for a 200-4r. I managed to get the trans, correct driveshaft, and shifter from a buddy for $150, so it wasn't as costly for me as it may be for others.

Hasn't been a thousand miles yet, so no I have not gone to the track. I'm just telling you it accelerates like a bat out of hell and if you don't believe me than you can just sit back and wait till I go to the track. Ask other members on this forum, Jbreau, jrm81bu, and others run the 700r4 with great success on the street and track.

A good way to tell if you have a posi is to pop the differential cover and look into the third member. Right in the center where the spider gears are, there is an "S" clip in there. That is a dead giveaway. Not all monte carlo ss's came with a limited slip diff. I came across an 87' monte carlo aerocoupe in the yards once and it had an open 3.73 diff.

Another way is to just spin the wheels. They both turn in the same direction. Some of the them came with springs and clutches.

If your looking for a 7.5 posi, I've found in the yards a lot of the mid to late 80's caprices had a lot of limited slips as standard equipment. Unsure of type of carrier caprices had, 2 carrier or 3, more than like a type 2 carrier which means you won't be able to go bigger than a 3.23 gear.

I am running 4.10 gears with my 700r4 and in o/d im running 2300-2500 at 60-65 mph give or take......If your looking for a posi unit, you can still use your existing gears..No need to get new ones. Like Pat said, pull your cover or jack up the rear end and put the car in neutral and manually spin a wheel, if the other side spins in the same direction you have posi...Or better yet, do a brake stand and see if you have the one wheel peel or two strips