Converter stall
Thread Starter
Teching In
Joined: Aug 2020
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Converter stall What stall speed converter are guys with a similar setup
6.0 ly6 , summit racing stage 2 turbo cam , vs racing next gen 7875 turbo. Its in a 68 cutlass with 4.11 gears now, probably will put in 3.55s.
As of right now running it n/a i have a 3,800 stall and its way to loose. i was thinking something around 3,000 should be good but i wasnt sure.
Trans is a th400
6.0 ly6 , summit racing stage 2 turbo cam , vs racing next gen 7875 turbo. Its in a 68 cutlass with 4.11 gears now, probably will put in 3.55s.
As of right now running it n/a i have a 3,800 stall and its way to loose. i was thinking something around 3,000 should be good but i wasnt sure.
Trans is a th400
I have a 6.0 with Summit stg 2 cam, turbo, 3.50 gears, 295 drag radials, in a square body, 4L80E. It has a 10" converter from Trans spec., was a generic 3500, but stalls more because the truck is heavy (you really need to spec a conv. to the car). Anyway, I think it stalls to much, creates a lot of heat in the trans, will run over 200 degs, unless locked up. In lock up, you have to be going pretty fast, or feels like no power, esp around 1600-1800. I usually leave it in 3rd if 50-55 MPH, and in lockup its around 2K, which seems to make it happy.
Whats the intended use of the car? 1/4 1/8? street? Weight? Redline? What brand converter do you have now? I can tell you I've picked up every time i've went looser, but all converters are not made equally. Getting one that's loose down low and "locks up" pretty tight up top is generally tough with the cheaper converters. My statement holds true with the $1000ish 9.5" PTC converter. But they won't lock up tight with the loser stators in them unless you rev them out a bit. I run my summit stg2 to 7200 with the ls6 intake on my 4.8. Don't be afraid of RPM. And don't go so tight that the converter drops down in the PK TQ (peak cyl pressure) range on the shifts. It's much harder on things than just revving them to 7k ish. I'd really like to rev out to 7600 at least.
Thread Starter
Teching In
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Intended use is street + 1/8 mile. The car weight is roughly 3,600 #s, Right now the converter is a jegs 60431 hxd. Rated stall is 3,500 to 3,800 rpm. The reason i asked the this question is i have a local converter company building me a billet converter for a great price but he asked me what stall speed i was looking for. thinking the one i have is too loose i said 3,000. But knowing this jegs one is probably just loose down low i may change what stall speed i am shooting for. I have not had the engine dyno tested so i am kind of shooting in the dark for the correct stall. I was just hoping someone with a similar setup could steering me the correct direction.
Does the TH400 have a trans brake? 3000 is low, esp without a trans brake. I'd go 3300-3400 w brake 3500-3600 without... But your converter guy should be telling you what stall you need. Thats a a heavy car, id want the 4.11 gears in it for your best 1/8th.
What is a "great price" ? Basically if the guy knows your combo and intended use, he should be telling you what stall you need. If he doesn't know, then he isn't familiar with turbo converters and you shouldn't use him, period. Trust me you don't want to be pulling the converter in and out 5 times to get it right. Go to the folks that have the turbo converters nailed down pat IMO. The PTC is just a plain awesome unit and honestly aren't that expensive. YOu give them your build specs and intended use and they give you a converter... it's simple.
I'm not trying to talk smack about your converter guy. I'm just saying they should know what stall your turbo.engine needs if you give them the information. I fought converters for YEARS w/ multiple turbo cars and converter companies/brands... until I installed a PTC. Lots of good converters for turbo cars out there these days. I just stick with what always works. They also have a 10" $450ish converter thats really nice for the money. Just has a bit more slip up top than the $1000 9.5". I run them both.
What is a "great price" ? Basically if the guy knows your combo and intended use, he should be telling you what stall you need. If he doesn't know, then he isn't familiar with turbo converters and you shouldn't use him, period. Trust me you don't want to be pulling the converter in and out 5 times to get it right. Go to the folks that have the turbo converters nailed down pat IMO. The PTC is just a plain awesome unit and honestly aren't that expensive. YOu give them your build specs and intended use and they give you a converter... it's simple.
I'm not trying to talk smack about your converter guy. I'm just saying they should know what stall your turbo.engine needs if you give them the information. I fought converters for YEARS w/ multiple turbo cars and converter companies/brands... until I installed a PTC. Lots of good converters for turbo cars out there these days. I just stick with what always works. They also have a 10" $450ish converter thats really nice for the money. Just has a bit more slip up top than the $1000 9.5". I run them both.
Thread Starter
Teching In
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No trans brake as of yet, Not sure if its going to be a 9.5 or a 10" as of yet. but it will be a billet cover built for my ly6 engine ,no more adapter hub i told him around 800 crank horsepower so thats why its going to get the billet cover. for $550. I have one of their converters already in my buick grand national and spools great. I have also used ptc in the past and they worked great. I work at a transmission shop and we have been using there converters for awhile and i do trust them, we have not had any real failers with them. I just question if they know without a dyno sheet to know if they are choosing the correct stall speed.
TECH Fanatic
Joined: Feb 2015
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The best thing you can do is contact PTC and give them all the details so they can correctly spec a converter for your goals The more honest accurate info you give, the better the converter will be to meet goals. The worse thing to do is call a converter company and tell them what you want. That leaves you stuck/responsible for the results.
