kaiserbud

I think I will be converting from TH400 to a 700R4!!! I was checking the CF on pros/cons.... I do not think there will be a definitive answer - almost like the Big Block/Small Block debate.......

I found conflicting posts on the ease to install the 700R4. I guess that is one of my concerns... ...

But another reason for my post is gearing. I see two sides to the gearing issue. My motor is a 427 /500hp hydraulic roller w/a 373 rear gear. I would rarely hit the strip - general pavement pounding.. and maybe some autocrossing. Its fun to smoke the tires, but I don't know if I would 'want' to do that 'all' the time. My enjoyment is the quickness from a 30mph roll

The 2004r has more even gear intervals, and higher OD. The 700r4 has the really high 1st gear and a 2nd gear that is not so 'progressive'. Either OD is a godsend to me. I noted the gear ratios below - just fyi - but why couldn't someone change the gears in a 700R4??

TH350 2.52:1 1.52:1 1:1 N/A
TH400 2.48:1 1.48:1 1:1 N/A
700R4 3.06:1 1.63:1 1:1 -0.70:1
2004R 2.74:1 1.57:1 1:1 -0.67:1

TimAT

The gears in the trannys are pretty well set by design. Diameter of the planetary sets and physical room inside the case. When I went to GM's school on the 700 about a hundred years ago, they gave the 1st gear ratio at 3.06, then said it doubled thru the convertor, because it's unlocked in 1st, making low's effective ratio 6.12. If that won't get you rolling, someone tied a chain to your car.

Other tranny's were used in more applications, so some were built with different ratio's. THe 400 comes to mind- they used it from vettes to 1=ton trucks and motorhomes that needed a lower 1st gear.

markdtn

THe install is fairly straightforward. You need a tubular or modified crossmember and shorten your driveshaft. If you have a TH400 you need a different yoke. A 4-sp or TH350 yoke is the same as a 700R4.

I have TPI fuel injection and 3.7 gears. I do find 1st to be useless. I would consider a swap to a different rear eventually. I have a 3.36 that I will eventually swap to.

ajrothm

FYI

This week I called Art Carr about their 200R4. There is a kit that comes together, its an 800hp rated 200R4, custom 9.5" converter, tranny cooler, dipstick and tube for $2400. They also sell the Painless wiring lock up harness for the converter lock up which will make a 3500 stall NICE on the freeway.

That is the route I am going. It fits in the TH400 location without mods to the crossmember and more efficient then a Th350.

jdmick

I put in a 700R4 but that was mainly because I got one fairly cheap and my rear ratio is 3.36. With the kind of power you have along with a 3.73 rear I think a well built2004R would better serve you. No crossmember or driveshaft mods and a taller first gear. Not that the 700 install is particularly difficult but why mess with those things if you don't have to. Either way you will love the overdrive.

kaiserbud

Yes - the OD...... You know - I never considered making a rear end change.... I guess before I did that I could spend more $$ on the tranny. But the bank account may hold me to the 700R4

I have seen multiple posts saying there is and isn't mods to the underbody.... is there or isn't there.

I ddi not know that the 460LE was the 700R4 - what is the scoop there? Was the 460LE the evloution of the 700R4?

kaiserbud

I understand your points and agree - I contacted the other CF member that I was working with to buy his 700. He was real understanding about my decision and going with a 200. I will have to wait a while longer - but it will be worth it.

Buffalo Dude

Go 200-4R. It almost installs itself. Almost.

Seriously, if I had to swap another trans I could probably do it in the span of a day now that I know what I'm looking at. See my profile for my 200-4R swap.

redwingvette

Go 200-4R. It almost installs itself. Almost.

Trans install

kaiserbud

thanks - I will do the 200 - just a matter of when