allison 644 shift points?

[mccarlk]

talked to a local allison dealer today regarding finding the spacer ring between the convertor and flex plate,any how, the guy said i should have my trans dyno tested to make sure it shifts the rite time for the engine? what does he mean, the trans has been in the bus for years, mind you i am changing the engine , both are 8v71 s, and input would be great, thanks again, ken

[JackConrad]

What I think he was referring to is different horsepower outputs from engines require different shift points to keep the engine in the "sweet spot".  The Sweet Spot will vary depending on engine horsepower (timing, injector size, turbo or non turbo, displacement, etc.)  Jack

[luvrbus]

I wouldn't worry about shift points now if your tranny came from the same type engine the transmission shifts at certain rpms for each gear if you do not like the rpms that it shifts when you change the oil later you can change it your self not hard to do 1 click 40 rpms not a rocket science and if you spend the money for the dyno you may not like that pattern just go with what you have and save the money    good luck

[mccarlk]

thanks guys , this board is a real life saver, or did i mean money saver!!!!!!!!!

[buswarrior]

hmmm 8V71 a the concept of sweet spot....

Run engine briskly to as high an RPM as it will scream, grab the next gear, hope for the best..

Repeat?

happy coaching!
buswarrior