yj stroked and blown what stall speed ??? Tf999

[bandon]

Long time no post, Help, I cant seem to find any decent info on which stall speed would best suit my 4.56 35" Yj.
Seems there is a huge loss of power some where between the motor and the ground. I'm tempted to go low to match the powerband but would like to go hi to get a bit of launch out of it.
Also haven't found any good powerband charts for rpm data with the 4.6


Thanks

[Biggrnjeep97]

What do you use the jeep for? Road? Rock crawling? Id say 1800-2000 would be a GOOD guess but you REALLy need to call a good converter company like ATI or Hughes. Dacco my have an off the shelf for cheap. They will want info like cam specs, CR, tire size, gears. Be aware that a higher Stall will warrant a larger trans cooler.

[bandon]

Sorry for the lack of details of my jeep. I had a huge sig that listed all my cool mods but it didn't pop up. My jeep has become a simple DD with a LOT of power. Already have the trans cooler plus fan. Dent do much highway driving so I'm not concerned about top end or High rpms. I guess I just want to chirp the tires in my Tf999 on the way to work.

[Cheromaniac]

With the TF999 3-speed auto tranny, 4.56 axle gears, and 35" tires, the engine will be spinning at 2400rpm at 55mph in the 1.00:1 ratio 3rd gear. Therefore I suggest that you go for a 2400rpm stall converter, and add the biggest stacked-plate auxiliary tranny cooler you can fit in the available space with a small electric fan.

[bandon]

biggrnjeep97 says 1800 to 2000 Dino says 2400, Thats a big range, I just want to chirp tires a little, I'm confused some tell me get a towing converter very low stall others say go High ala muscle car. What happens with a tow converter? Does it lock up before the engines powerband ? Then what? Dino whats the stall in your cherokee ?

[Biggrnjeep97]

Have you dyno'd the jeep yet? Both of our guesses are just that; guesses. They are both right for different reasons. Unless you have an accurate dyno chart to see where your powerband is, i mega-turbo-super-duper suggest you call a converter manufacturer. They will know what to do but cheromaniac is right, 1) you are going to need a GIGANTIC cooler (higher the stall, bigger the cooler) and 2) you MUST end up with a happy medium between cruise RPM and your powerband/stall. You dont want be going down the interstate nowhere near your stall. Youll fry the trans in no time with that kinda heat. JMO, good luck.

[Cheromaniac]

biggrnjeep97 says 1800 to 2000 Dino says 2400, Thats a big range, I just want to chirp tires a little, I'm confused some tell me get a towing converter very low stall others say go High ala muscle car. What happens with a tow converter? Does it lock up before the engines powerband ? Then what? Dino whats the stall in your cherokee ?

My Jeep has a manual tranny so there's no converter.
A towing converter stalls at lower rpm and generates less heat. A higher rpm stall converter will produce more heat (hence the bigger cooler) but it'll also provide torque multiplication up to that higher rpm so each has its own advantages (and disadvantages). Either way I recommend that you install a tranny oil temp. gauge.
The best choice depends on what type of driving you do (and whether you do any towing) but what you don't want is to be towing a trailer up a highway incline with your engine running below stall rpm 'cause the converter will heat up the tranny oil and kill the tranny.

[bandon]

P1010200.JPG

Thank you both I will give it some MORE thought.

[Cheromaniac]

Blimey, I don't think even the flight deck of the Space Shuttle had that many gauges!

[SilverXJ]

What are the two low temp gauges on the bottom row for? On either side of the clock

[Biggrnjeep97]

I'm gonna guess the one on the left is EGT and the one on the right is IAT.....

[bandon]

Yes you are correct EGT and intake air temp.