Justifying a 700R4
Thread Starter
Drifting
Joined: May 2007
Posts: 1,491
Likes: 2
From: North Royaton Ohio
Justifying a 700R4
So I was reading some threads a couple days ago and I ran across some transmission topics. I did a little research and found out how truly perfect a 700R4 would be for me. My only problem is I JUST had my TH350 rebuilt a few months ago, and I can't justify spending that kind of cash on something that I really don't need, but would make an incredible difference in my car. I do quite a bit of highway driving, and the lower first gear makes me drool. I know I could put an overdrive on my current transmission and put lower gears on to get a better launch, but it seems kind of like the benefits of the overdrive would be canceled out by the lower gearing.
I know people on here have swapped out TH350's for R4's in the past, and I was wondering, if they don't mind sharing, how much they shoveled out for it, and how difficult the installation was. Did you have to modify the crossmember (I have an 81, so it's different than early C3's)? Any little problems that came up (shifter linkage, consul plate problems, things like that).
Input grealy appreciated
I know people on here have swapped out TH350's for R4's in the past, and I was wondering, if they don't mind sharing, how much they shoveled out for it, and how difficult the installation was. Did you have to modify the crossmember (I have an 81, so it's different than early C3's)? Any little problems that came up (shifter linkage, consul plate problems, things like that).
Input grealy appreciated
Drifting
Joined: Aug 2007
Posts: 1,924
Likes: 6
this is what the 81 crossmember looks like (trying to help)
and I'm not trying to hijack your thread, but how are you controlling the lock up 350 you have with your swapped engine / carb?
and lastly....
I'd go with a 4 speed. (but I'm seriously old school) I never felt like I was driving mine as an automatic
and I'm not trying to hijack your thread, but how are you controlling the lock up 350 you have with your swapped engine / carb?
and lastly....
I'd go with a 4 speed. (but I'm seriously old school) I never felt like I was driving mine as an automatic
Thread Starter
Drifting
Joined: May 2007
Posts: 1,491
Likes: 2
From: North Royaton Ohio
When I had the th350 rebuilt I had a new regular torque converter put in.
And believe me, I'd LOVE to put a 4 speed in, but that's just a ton of work. I don't feel like cutting holes in my floor and changing the shifter plate and all of the other accompanying garbage that is usually overlooked.
Plus I have size 14 shoes and it's already pretty cramped by the pedals. I don't think I could do another one!
And believe me, I'd LOVE to put a 4 speed in, but that's just a ton of work. I don't feel like cutting holes in my floor and changing the shifter plate and all of the other accompanying garbage that is usually overlooked.
Plus I have size 14 shoes and it's already pretty cramped by the pedals. I don't think I could do another one!
Drifting
Joined: Aug 2007
Posts: 1,924
Likes: 6
When I had the th350 rebuilt I had a new regular torque converter put in.
And believe me, I'd LOVE to put a 4 speed in, but that's just a ton of work. I don't feel like cutting holes in my floor and changing the shifter plate and all of the other accompanying garbage that is usually overlooked.
Plus I have size 14 shoes and it's already pretty cramped by the pedals. I don't think I could do another one!
And believe me, I'd LOVE to put a 4 speed in, but that's just a ton of work. I don't feel like cutting holes in my floor and changing the shifter plate and all of the other accompanying garbage that is usually overlooked.
Plus I have size 14 shoes and it's already pretty cramped by the pedals. I don't think I could do another one!
well, it was really much easier than I expected, and I'm a team of 1 here. The hardest part was locating a shifter bracket that would bolt onto the 81 crossmember. I eventually ended up with 2 (and 4 that were from other years)
{lock up}
but I thought the lock up was controlled by the CCC. cause theres that 4 pronged electrical connection that goes into the trans... just curious.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I know people on here have swapped out TH350's for R4's in the past, and I was wondering, if they don't mind sharing, how much they shoveled out for it, and how difficult the installation was. Did you have to modify the crossmember (I have an 81, so it's different than early C3's)? Any little problems that came up (shifter linkage, consul plate problems, things like that).
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
As for cost. In 1988 OD was the rage product. So after reading a Car Craft article I thought that I could do it. At the time Jeg's or somebody was selling these $1400 450 HP big handling 700R4 with lockup in 4 gear only. I melted down a few and ended up with a $3000 racing 700R4 and an $1100 dollars 9.5 inch 3500 stall TC.
Last edited by gkull; Sep 21, 2007 at 05:36 PM.
Instructor
Joined: Apr 2006
Posts: 212
Likes: 0
From: Woodland Park Colorado
I wouldnt let a rebuilt 350 hd stop me from putting in a od trans in. You will love the difference. I went with a bowtie unit stage 2 and pulled a perfectly good 350 hd out of the car. I have about 1600-1700dollars in it with shift conversion and crossmember which is nice also. Few hour install with air tools with sons help and am very happy. My 383 now gets 15 city and 20 highway with 3.55 gears. I went with a 2200 stall and my take off is nice. Some have rebuilt there own and gotten by alot cheaper but I just work overtime at work and pay for mine. Good luck but all I can say you will love the od trans.
Best Regards
Best Regards
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Team Owner
Joined: Jul 1999
Posts: 65,492
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From: Orange Park Florida
Correct, not only are there not mods to the cross support, none to the driveshaft, but IF I had known of the 200 4r being in existance I would have done it some ten years ago, instead of the 700 with all i'ts attendant mods, and the problems with widening the tunnel on the pass side for clearance....my '72 was a Muncie car,...so maybe the tunnel will not need widening for an auto car.....dunno....
essentially the 200 4r is as close to bolt in as you can get....
Drifting
Joined: Nov 2002
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From: Shore NJ