What stall-speed would you recommend for my hemi-killer cammed (241/241 .491 lift roughly) stage 1. 10:1 compression, TA intake, 3.73 gears. I had always thought you stall a converter at peak torque, but my trans guy thinks I'm too high. Street manners aren't too critical as it is a lock-up unit so slippage while driving is taken care of. I also sometimes run about 200 HP of nitrous. I'll probably be upgrading to the stage 2 heads within a year along with a similar duration cam with more lift. I assume the stall-speed recommendation be higher then? TIA
:beer Hi Adam,I am running the same combo as you,except I have the kenne-bell cool runner intake. I am running a art carr 3500 stall converter and the car launches real nice, shifting the gears at 5800 rpm. Dont know about the nitrous though. GOOD LUCK, Chris
The rule of thumb is to get a converter that will stall at the rpm where peak torque occurs. I know as I talk with more and more people who have been putting their cars on chassis dynos, they are almost always discovering that they put too much converter into the car. As some of thes people have dropped back the stall, they found they made more power to the rear tires. Jim Burek
Jim, I'm curious. Does the information in above thread apply to street driven cars also, or, should a lower stall converter be used for a primarily street car as a compromise for reduced operating temps, as slippage will seemingly create unwanted heat? Matt
Converter Stall Jim B. It's interesting to hear your statement on converter stall right at the torque peak. I'm glad to hear that. I ordered my converter from PTC in Alabama, which is a well respected converter manufacturer among Stock and Super Stock racers. I was originally planning to run my car is "GS Modified" in Bristol so I was limited to a 9" converter. I called Kenny Ford at PTC and talked to him about my application and gave him my dyno numbers. My torque peak is at 5200 RPM and peak HP is at 6000 (unported heads). The converter he came up with should stall at around 5200. It sounded kind of high to me based on other's experience, but I am anxious to try it and see what happens. PTC has a great reputation.
pick-the-stall-speed OK, you guys tell me where you'd get the converter for. I'll spill the beans on what I have after a few recommendations. and why-o-why won't the image work?
Since slippage while driving isn't an issue, I'll call a 3500 stall too. I have the same cam, 3.42's and a 2400 stall, and it's not enough for the track....
Adam My wifes old car had the Hemi Killer in it and we ran a 3200 stall with 3.90 gears. and that thing was fun to drive. The car was in the 1.6 sixty foots all the time and would lift the drivers side tire about 5 inchs every time Amy hammered it. When she ran the car she left it in drive and the car would shift at 4800 and the damn thing ran 12.25's till the you couldn't stand it anymore. That car would run the number over and over again. She has trailered more than her share of club members I must say(she's never beat me:TU: ). But there is the fact we have never raced each other or that fact may be different. .
Right now I am running an off-the-shelf 4000 RPM converter. It is pretty much right on 4000 at the 5200' elevation I'm racing at. After talking to the converter builder (YANK) it sounds like it wouldn't be so good at sea-level. probably more like 5000 RPM. I currently shift at about 5500 RPM. I suspect what I have may still be appropriate for a bigger cam when switching to the stage 2 heads. The goofy part is I have a 200-4r in this car and wonder about its use as a street car (At that point I might as well go back to a TH400) if I get much wilder with the cam. . Anyone have any experience with the TA solids milder than the 308s?
Converter questions can be tough to answer.. For a primarily driven street car, you should be better off with a more conservative lower stall converter. What will you be doing most with the car? Just say your cruise rpm will be in the 2400 to 2600 rpm range, a 4000 stall converter would be in a slipping mode under these circumstances. For a pure or mostly drag car, a higher stall converter can work good. I don't feel a 5200 stall converter in a combo that shifts at 6000 rpm is exactly ideal, in this application, the converter does not miraculously lock up at 5200 rpm. Think about it, you are only shifting at 800 rpm higher than the stall rpm, you can't convince me that the converter is efficient at 6000 rpm. I stated once before that I drove a car out here with a 700-r4 tranny with a 4000 rpm stall non lock-up converter, this think was a piece of crap to drive. The thing wanted to cruise in od at 2200 rpm, but the only time it would do that was if you were on totally level ground givng it just enough throttle to keep the car moving forward, any throttle movement at all would try to send the rpm towards 4000, any slight , and I mean slight incline in the road and the rpm would go up. Why have an overdrive. High stall converters can be great in a drag race situation, but the car is awful to drive on the street.. Years ago I watched a guy that I used to race my nailhead powered T-bucket against go through the converter thing, he kept changing the converter to higher stall to launch the car better, which it did, however, the mile per hour kept going down and down so his net et stayed the same. Now before I get flamed here, I know converter technology is always changing, hoefully for the better, I'm just sharing some things I have learned over the years. Jim Burek P.A.E. ENTERPRISES Give me a switch pitch or give me death!
Jim, Thanks for your answer. This is the conclusion I have drawn ... exactly! I also agree with the switch pitch way of thinking. I have a switch pitch pump and forward clutch assembly that will be built next. I'll be calling you for a converter for this , as, I've been told that you are the man for the job! I had a switch pitch in my first GS(350) and loved it. Suprised the hell out of a more than a few Mustang owners with the combo! By the way, the N-25 tips you make are beautiful !! Thanks again, Matt
Thank you, I am proud of the tips too. I have been surprising people with the s-p converters for years. The absolute best one is our 11 unit that we call our 5000 series, that is really a sweet unit, but it is expensive. Jim Burek
