The torque converter in my "T" seems to have no stall. At an idle it's pulling, and the engine bogs down when I apply the brakes, sounding like it's going to stall. The transmission (th350) and torque converter appear to be new. I have set the idle low, and it still pulls. Is this converter defective? Thinking about installing a 1500-2000 stall converter.
Motor and camshaft size can play a part in this symptom. A bigger cam wants a higher idle, but a big stock type converter wants to start working in that range thus causing what your describing. If you know the cam specs, that can be very helpful. A higher stall can be a cure---or a band aid.....
The engine is a sbc 283. It sounds like it has a pretty snotty cam. The guy I got it from didn't build it and didn't know any of the specs...
No stall would mean that the converter never fully engages enough to overcome a load, like the brakes. What you have is a very low stall speed. It can be perfectly normal, depending on the specific converter, which would relate to whatever car it was originally intended for.
You have a super light car with a self described "snotty cam" + its a small CID engine. Put more stall in it and have a nice day. By the way ...whats the rear end ratio?
Many things could be going on. 1. It's a very light car. This may be no issue in a fullsized sedan. 2. Because it's such a light car the stall speed is lowered. Thus lowering idle does not help as it is such a light car ....It want's to creep even at low idle. 3. 283s are small cubic inch V8s. The smaller the engine the bigger the cam. Vise vesa.... The bigger the engine the smaller the cam. A 400 might sound and act stock. The same cam out of that 400 may lope in the 283. 4. You may have to run a higher stall just to get factory full size sedan drivabilty in such a light car. What I mean here is you may need to run a 2500 stall to stall your car at 1600 1800. (I'm just using these numbers as examples)... 5. there could be other problems with induction and the transmission. Personally I think such a light car is your main issue.
As mentioned..A bad combination, most likely. 3" stroke, big duration , light car. A 9.5 245 mm converter is not a band aid..It's what you need. Relatively inexpensive, seeing it's a plentiful , readily available core. I'd want to know the duration @ .050 and rear ratio, minimum.
Do any of you guys remember getting Vega converters back in the day and peeling off the air cooling shroud? worked pretty good on light cars....
Yep..Very inefficient design for V- 8 cars. You're right about light cars only. The turbine spline would rip right out of them. Cheap stall...That's all.
I agree that the combo is mismatched, it sounds like you need less cam or more converter. At what rpm does the engine start to "come alive"? That should give you an idea of what stall speed you need. As previously mentioned, vehicle weight, gear ratio and engine torque factor into the decision. My '58 had too much cam for the stock converter, instead of replacing the converter I swapped the cam for one with a "RV" grind. It idles nice and makes great torque from off-idle to 4000+ rpms, which is also the engine operating range encountered in normal driving.
You'll get different opinions on high-stall convertors... I'm not a fan for a street car. It goes like this: The factory uses a low stall speed (typically around 1200 RPM, give or take). One advantage is it 'locks up' at a relatively low road speed, so at low speeds or in traffic, it's not churning the trans fluid as much so you get lower fluid temps and it improves fuel economy. But you need an idle speed of about 600 RPM to prevent 'creep'. But your lumpy cam needs more idle speed to keep running, so now you've got excessive creep. Higher stall, no more 'creep' issues but now the convertor no longer locks up at that same slow road speed. More heat in the trans, and fuel economy suffers a bit. Plus part-throttle response will tend to be 'mushier' as the motor needs to turn more revs to achieve lock-up. As mentioned, car weight, rear gears, and torque delivery are all factors that will affect stall speed, so it may be best to talk to a specialist instead of guessing and buying something off the shelf. The best fix?…. Install a 4-speed!
I see some of you took my Band Aid comment the wrong way. I only meant it as there could be potentially other issues we don't know about with the information that was initially given at the time I posted. But I did say the higher stall could be the cure as most here have agreed. Sorry If I raised any doubts, sometimes typing/reading looses the emotion behind the statement.
Thanks for the advice guys. Wish I had more information on the build specs. As I said before, the previous owner had no information on engine specifications other than prior to him owning it, was equipped with a tunnel ram with two four barrels. He also said that it had been stroked... The engine runs great so I really don't want to tear it down.