i use one in pinkie, 8" 5000rpm stall, not entirely sure how it all works but.........
1), ask dunc
2) enables you to build much higher revs on the brakes, and consequently launch at mental rpm,
3)as above !
4) if as high as mine, on the street you tend to rev to about 2krpm before you start to move !
5) same difference on the street as the strip, i rarely lose traction, even on cacky tarmac, the convertor takes some of the slip, if that makes sense !
6) difference tween wheels up and not ! as mentioned before, if my brakes were strong enuf to hold the car still, i could effectively launch at close to 5000rpm, wheels up and sub 11's on way !
7) my old street cuda ran a 3500rpm convertor 10", made alot of difference in the way the car hooks up over the standard one i took out.
Derek, a torque convertor needs to match the camshaft you are using, stall speed is torque dependant, the more you've got the more any given convertor will stall to, for instance a con vertor might stall to 3000 behind a small block, that same unit might stall to 3500 behind a big block. So, basically a convertor matched to your particular combination will improve performance. To answer your questions,
1) It slips until it gets to the point where it is designed to lock up (no normal convertor ever locks 100%)
2) It allows the car to pull away in the torque band of the engine.
3) see 2!
4) They can get hot, bigger than 10" and less than 3000 stall shouldn't be a problem.
5) yes
6)yes
7) Yes, the one that matches your combination!
Ok let's talk specifics, I'm guessing you have a mild hydralic cam, if that's the case then the kind of covertor you need shouldn't cause you much grief. If I was you I'd get a custom convertor built to suit your car exactly, shouldn't cost an arm and a leg, I would think Neil Willet could help you there. The convertor manufacturer will be able to advise you how big a cooler you need to run.
“Buy it broke and fix it wrong, it’s the American way”
Blue, this is my engine spec, am I right in thinking that I am not getting the best out of my engine as I have a standard converter, or am I thinking it wrong. The enginge was built a few years ago.
Are we there yet dad ..... 10 to the gallon but worth it.
MMA Public Relations Officer.
MMA South London and Surrey Area Rep.
Blue, how will a 2800 converter affect every day driving, Will the revs have to be high to pull away as Hugh says, or is that because his is a 5000 converter
Are we there yet dad ..... 10 to the gallon but worth it.
MMA Public Relations Officer.
MMA South London and Surrey Area Rep.
lol, mine is a 5000rpm stal speed, so effectively it'll slip its nuts off until there's sufficient weight on it to pull along, ie, around 2000rpm before i move,
get it right and your car will pick up like a scalded cat !
Under normal driving you will notice a little slippage Derek, but it won' be anything too serious and nothing at all like a 5000 stall 'vertor, which must be like driving a car with a permanantly slipping clutch! Another point I ought to mention, if your car suffers from a lack of traction on the street or at the track then a higher stall convertor will make it worse because you are effectively increasing the amount of torque at the tyres, more power is useless if you can't get it to the ground!
“Buy it broke and fix it wrong, it’s the American way”
A convertor basically consists of an Impeller a Stator and a Turbine
The Impeller is engine driven
The Turbine drives the trans
The Stator sits inbetween the two and can only turn forwards, the Stator redirects oil flow onto the Turbine at a better angle but also during acceleration the oil flow is on the front sides of the stator vanes which lock the clutch forcing oil onto the turbine with great force
A better way of explaining this is: When there is a great difference between impeller speed and Turbine speed the oil flow locks the Stator and torque multiplication occurs BUT when the Impeller and Turbine are closer together the oil flow tend to pull the stator in a forward direction letting it coast along.
Stall speed is just basically when the impeller starts to move the turbine, It is determined by several factors, including the distance between the impeller and the turbine and the design of the stator.
Bigger Cams make less power lower down so putting the trans into drive with a stock convertor and a bigger cam creates a load on the motor that the motor is not capable of sustaining, so tickover is terrible at best, at worst the motor will stall, idle in neutral can be fine but in drive it may stink of unburnt fuel.
Bigger cams also push the power further up the rpm range and this is where the stall should be heading, if the cam and stall are matched then the load on the motor occurs at a point where it's making enough power to really move the car.
Convertor spec is also dependant on weight of car, rear end ratio, tyre height etc as well as the motor
It did me Blue!