helo,

im pulling the engine in my 1993 coupe automatic for some maintenance and a Cam n such. Due to the specs of the cam I found it a good idea to upgrade the torque converter to a higher stall, from my knowledge and experience stock stall is around 1400 to 1600. im on a budget, and want to know if I can use a reman converter for a 4L60E from a trailblazer/envoy. Reason for this is because they’re cheap and the one I am eyeballing is 2200 to 2500 stall, which is right what I want. the same company makes a 2000 stall converter for the same price for the corvette, but why not go for a slightly higher stall. transmission is stock (non electronic 700r4/4L60) and rear end is stock. motor will have a cam and some upgraded rockers and lifters, ported intake, cold air intake, short headers and full catless exhaust. can I make the 4L60E converter work?

From what I saw, people say it should work as long as the 4L60E converter is not for an LS.

 

It may be compatible. However, to be certain you must confirm that it is 30 spline and the same diameter.

 

I'm fairly sure the bolt pattern is different. The I6 Trailblazer converters are an easy upgrade for LS applications. But for SBC I don't think it will bolt up to your flex plate. You could however drill new holes in your flex plate. Also really check and make sure you have the proper gap. I always shoot for 1/8" gap. I use a 1/8" drill bit as a gauge. Basic hardware store washers will work as a shim to get the correct gap.

 

If it fits the LS it won't work. Lt1's take the 30 spline from like '86-97.The early S10 and blazers worked ok. I ran one for a few years and it's still in my garage. 24202310 was the GM part number.

 

Slightly restalled ones from smaller engine vehicles run okay (I run a 4.6 converter in my 5.4 truck, no issues and tossed a 302 converter behind a 351W in pal's truck), problem is the STR is still low and they become increasingly inefficient the higher they are restalled with a large diameter. Not to mention the lack of quality over all...clutch material, bearings, etc. It is one of those pay to play things. The smaller diameter ones allow the vehicle to rev quicker too due to less mass. Think like going from a 22lb flywheel to a 14lb, one knows the difference especially from a dig. Or going cast to forged wheels.

2200-2500 is nice, honestly what vehicles needed stock with the 60E and its variants due to the huge RPM drop between the first and second gears.

Depending upon the powerband of that cam, you may and probably will like more stall once you drive something with a converter in it. It does not just slip and slip until that speed meets, the TC is just a fluid coupling. Now if you want a 3400-3600, they are a pile of fun but become tiresome on the streets if you have to daily. I did a 3800 for a bit, hair wild but with a high STR and 9.5" it was not awful.

 

One work around for this is you might be able to swap the front input shaft/pump assembly.

 

If you are pulling it down that far, you may as well refresh the trans...which I 100% believe the OP should do anyway after over 30 years. Internal seals weep with age, regardless of miles. To swap inputs means you have to break down the input drum or swap and they leak at the spline area with age. Plus the OE sungear shell is **** as we all know, the rev input drum bows in due to the band apply, 3-4 clutches cone...

Best is to buy a nice converter, do a mild shift kit, and some external cooler if you find a spot. I much prefer the Transgo HD2 for the 60E over the other kits. Some I much prefer the Superior kits. Anyway, grab the Superior billet OD servo, Transgo HD sep plate, plastic check *****, output shaft seal, pump seal, dipstick tube seal, and rock out. You always want the 1-2 as mild as possible on them, just how these are due to band apply so 0.063-0.070". 2-3 varies depending upon the wear of the clutch pack, apply piston health, and friction quality, 0.093" is good place to start. 3-4 is usually really soft, so not an issue bringing it out to 0.093" For the 1-2 accumulator bush use the WHITE spring as these have the larger 093 aka Vette servo stock.

Note, with a looser converter the shifts soften. You may need to go back in and open the feed holes more according to your firmness taste. It is subjective.