700r4 swap questions.

[Phoenyx]

OK as some of you already know I've decided to do a 700r4 swap in my Malibu. And I have a few questions. But here's a brief history first.

OK so I just had a 355 installed (about 400HP) in my car. Both me and my mechanic weren't to thrilled about the TH250 hooked up behind it. And he was really wanting me to do a 700r4 swap. And also as some of you may know I'm not what you would call a fan of the 700r4 lol. But he found me a deal on a used one, and we're gonna install it as is (with a new non lock-up converter, fluid, filter, new cable and maybe a shift kit). It has a little over 100000 miles on it and came out of a Firebird (not sure on what year) after it was written off. Got it for $200. We're thinking even stock it's better than the TH250. And since I run a stock sized tire it should hold up for now.

So here are my questions:

1- Will I be able to still use my column shifter (3 speed car)? I'm not worried if the shifter won't go into 1st. As long as I have P R N OD and D I'll be happy. Not really a fan on manually shifting a granny stick lol. What kind of mods will I have to make?

2- For the speedo gears. Is there any chance that the ones from my 250 will just swap over to the 700? The transmission shop charged me $260 the last time I had it re calibrated (swapped in some 3.73s), and I don't want to spend that much again lol. My tires are 24.5" tall.

3- Will the transmission lines work as is, or are they gonna have to be modified?

4- I already know about 3' is gonna have to be taken out of the drive shaft. And chance someone has figured out a stocker that would fit?

5- I've heard the I can use my TH250 (like the 350) dipstick, is this true?

6- Is there anything else I should know?

 

[84cutspreme]

1st off, you will not be able to simply switch shift linkage over to 700. Fabrication is required to make it work, throw of lever is different.
2nd, not sure on speedo gear, I used the driven gear from my 200c when building my 700. (if the same style, just see if they mesh together.)
3rd, I used the trans lines from 200c also, but fabricated a little to accommodate for external cooler.
4th, I don't know about direct swap driveshaft, I had mine cut.
5th, dipstick I dunno either, I bought new one to replace stock 700 one that was beat up.
6th...Only thing I would point out is that if you are making 400hp a stock 700 w/ 100,000 miles out of firebird probably will not last long. I rebuilt and upgraded my 700 and I am only running about 340hp. This is all just my experience and opinion.

Little notes: stock 700r4 case is rated @ 6250 max rpm
stock 700r4 & 4L60-E are both rated @ 350 ft/lbs max torque

Worthwhile upgrades: Sunshell, 3-4 servo, shift kit, boost valve, front pump vane setup(10 or 13), pump rings, input sprag, 2-4 band, accumulator setup, governor, 30 spline input shaft(if not equipped), and all torrington bearings.

There are many more upgrades that work nice, but most are not that imperative

 

[Phoenyx]

6th...Only thing I would point out is that if you are making 400hp a stock 700 w/ 100,000 miles out of firebird probably will not last long.

Yes I agree with you there. We just figure it will last longer than the 250 that's in it now. And if it goes, at least I'll already have a core for the rebuild lol. But either way I want to have it rebuilt by late spring/early summer.

Thanks for all the info.

How much fabrication for the shift linkage?

 

[84cutspreme]

I'd have to find out from my uncle, he fab'd the column linkage in his malibu that had 350 when he put in 700. I had floor shift in my cutlass and I just eliminated the linkage to column and installed micro switches in shifter. Seem to remember he had to cut and weld it, pretty simple. I think it was something pretty simple. pivot point was still the same, but the park position in the 200 was in the 10-11 o clock position and 700 was more like 9 or maybe it was opposite...I'll ask him this week sometime

 

[Longroof79]

You had mentioned using a non-lockup convertor. I would check into that further. I think there might be some valving issues in the valve body in order to run a non-lockup convertor as opposed to a lockup unit.

Also, I think the speedo gears for a 700 are physically larger than the variety used on the TH250, 350, etc. or at least the driven gear.

Your cross member will have to be modified to mate with the 700 mounting pad. I believe the mounting tab on the x-member may need to be extended slightly. I had an article in one of my old magazines where they were replacing a TH350 to a 700R-4 in a Malibu wagon.

 

[Phoenyx]

Well after 6 months of waiting the mechanic still hasn't put the damn 700r4 in. So it is getting towed home today with the 700 in the trunk. The transmission has been rebuilt, with sprag, vette servos, etc. I just need to find someone willing to do the swap (having no luck).

 

[JBreu]

The speedo gears are different and am not sure on the dipstick issue either, I would think that they are as well....Your lines will need to be replaced and that column shifter will need modified. Have you thought about doing away with the column shifter and go with a floor shifter??? ALso make sure up top you have the right geometry corrector and throttle linkage bracket. Also if you are running the non-lock up converter you should get a converter conversiuon valve from Transgo, part # 7-ccv, this redirects the fluid in your transmission.Good luck. It's really not that hard, As I did this swap last year, however I went with a BandM Pro-Stick ...

 

[CamaroAdam73]

Yeah, that 700R4 probably won't hold up much if any longer than your 250 will. Eitherway you'll be faced with a rebuild. If i where you, I'd buy that 700R4 anyways and have it rebuilt, and save up and buy all of the necessary parts to install it. So when your 250 does take a nice big metal sh*t in the street, you'll have a brand new trans setup 😀

 

[Phoenyx]

JBreu
It's a 4-door car that I'm trying to keep as much a sleeper as possible. Plus it has a bench, so that's why I want to keep the column. And yeah I have the right parts for the cable. And it's already set up for non-lock up. Did you use your stock x-member, or an after marker one?

CamaroAdam73
It's been rebuilt with all the goodies and should be good for 450HP.

Yeah, I'm kind of thinking I might see how it goes with my metric for now, so I can at least drive it before winter. I just gotta see how my breaks are (mechanic said AFTER installing the engine that it needed a stall).

 

[JBreu]

I originally had a th-400 in my car with a G-Force crossmember....I used that one, but had to buy a tailshaft for a late 80's caprice/caddy tailshaft to make it work...Check this link out for more :http://www.montecarloss.com/community/ubbthreads.php?ubb=showflat&Main=77525&Number=762415#Post762415