[68WarDog]

My plans are to upgrade my 70 T-400 transmission to a 700R4 with the least amount of work, so no 4L80E. I would like to keep the Jim Hand 10" stall. Is this possible.?

[RocktimusPryme]

If you want to keep your converter and want the least amount of work I would think a gear vendors unit would be the ticket.

[JLMounce]

My understanding is that you can't use the TH400 converter on the 700r4. Anyway, part of making that swap is the lockup function as well as the overdrive gear.

I worked with Cliff R and had a billet converter from TSP built for my 4l60e swap. That's the direction I'd go and they've got several options depending on what you're doing and what you need. I went with a billet face, triple kevlar disc setup, so I can lock it up under power.

I unfortunately haven't gotten my transmission swap done so I can't comment on how the converter feels and drives, but others including Cliff have seen good results with these when compared to the Continental converters that everyone enjoys.

If your current Coninental is in good service, you can probably sell it pretty easily to recoup some of the funds.

[Chief of the 60's]

Originally Posted by JLMounce

My understanding is that you can't use the TH400 converter on the 700r4. Anyway, part of making that swap is the lockup function as well as the overdrive gear.

I worked with Cliff R and had a billet converter from TSP built for my 4l60e swap. That's the direction I'd go and they've got several options depending on what you're doing and what you need. I went with a billet face, triple kevlar disc setup, so I can lock it up under power.

I unfortunately haven't gotten my transmission swap done so I can't comment on how the converter feels and drives, but others including Cliff have seen good results with these when compared to the Continental converters that everyone enjoys.

If your current Coninental is in good service, you can probably sell it pretty easily to recoup some of the funds.

700 and 4L60e use the same converter. Can you elaborate on this TSP converter? Stall? Cost? Is there a non-lock up option?

[RocktimusPryme]

Originally Posted by Chief of the 60's

700 and 4L60e use the same converter. Can you elaborate on this TSP converter? Stall? Cost? Is there a non-lock up option?

Tri Shield Performance, Cliff specced one out for me too but for a TH400. It who he is working with after Continental folded up. Mine is a 3400 but will good street manners as the old "tight" continentals were supposed to be.


Cost for mine was about $700, and they will restall it for like $150 if your combination changes. Ive been very happy with mine so far.

[JLMounce]

Originally Posted by Chief of the 60's

700 and 4L60e use the same converter. Can you elaborate on this TSP converter? Stall? Cost? Is there a non-lock up option?

My research suggests this is only the case if you are looking at late 700's and early 4l60's that were mated behind LT1 engines. When you get to later 4l60's mated behind LS based engines, the converters are different.

I ordered through Cliff, but also talked with Tri Shield directly. That can basically do whatever you want.

I purchased a monster, so it's a bit pricey at a bit over $800.00 for the converter.. I went with a "tight" 9.5" unit with billet cover, HD flanged hub, high performance sprag and triple kevlar clutches. It will handle full throttle lockup in gears 2-4.

As Rocktimus pointed out, TSP will re-stall these as needed for a nominal fee. They carry a lifetime warranty. I questions TSP directly on warranty and parts failure. Their response to me was "Try to break it." If you do, we'll fix it.

[taff2]

For a TH400 to 700R4 swap you will need at a minimum - a new 700R4 lock up (or non lock up) converter as the TH400 converter won't fit the 700R4, a new trans yoke/driveshaft (TH400 is 32 splines,700R4 is 27 splines), modified trans crossmember and rubber mount , 700R4 TV cable and corrector bracket for the carb, a big standalone oil cooler if you want the trans to live a happy life, etc. Get a late 700R4 with the 30 spline input shaft, and do the ususal build upgrades- an uprated sungear shell (The Beast is OK), new reverse input drum, wider 2-4 band, Vette band servo, Borg Warner sprags/roller clutch, a mild shift kit etc.

[Cliff R]

If you go 1987 or newer with the auxiliary VB the upgrades are done for you as far as hardened stator shaft, sun shell, wider low roller sprag, hardened pump rings, and better front sprag. I'd add the bigger servo and shift valve to allow heavy throttle/high speeds in OD without a forced downshift into 3rd. If you are building your own I'd use molded apply pistons like the later 4L60E's did. Avoid the very early units they used the same converters as the 200-4R's and nearly everything inside was "soft".

I prefer non-LU for retrofitting, just makes things easier everyplace despite the regurgitate nonsense on the Forums about overheating the trans. It's another topic full of miss-information, most of it supplied by "trolls" and folks that need to keep their day jobs. Sure, it's true if you buy some cheap POS shelf converter that flashes to 4500rpm's on a hard hit and never coupled for chit anyplace. IF you buy a good converter with efficient characteristics it will be fine. An added bonus is that in OD you will have a little bit of torque multiplication with light applied throttle for climbing grades or increasing vehicle speed on the highway. That's an added bonus as with the TCC engaged the engine will lug and if the RPM's are low enough it will "chatter" a bit until the converter un-locks.......Cliff

[69 Limelight]

I've had a 700R4 w/lockup for 6 years and 25-30,000 miles and love it. The OD makes it seem like you're in a different car. Wouldn't be without the lockup. I even have mine wired with a manual switch so I can lock in 3rd gear if type of road and/or speed limit calls for it. Never experienced a "chatter". If RPM's get that low it drops to 3rd (D) anyhow. I only have a "medium warm" 400 and it's never had need for additional torque multiplication in OD. If I wanted to accelerate that hard I mashed a little further on accelerator and transmission dropped into 3rd (D). If OP's vehicle being considered for 700R4 is in signature, a 468 shouldn't have a problem with torque. If not going to drive a lot of highway miles though, like I do, I wouldn't go to the time, trouble and expense of the swap. Just my opinion.