What detirmines the 700r4's shift points? Are they governed by RPM's, or vehicle speed? If it's the vehicles speed, then what speeds does it shift into 2nd? 3rd? Thanx.

 

Basically they are controlled by the governor and the shift timing springs on each of the shift valves. There is much more to it, but this should give you a basic idea of what is going on.

 

Were the shift points set differently on L98 cars than on L03 cars? It just seems that my new tranny shifts higher than it used to.

 

what does it shift at? that might help someone help you better..

 

it shifts from 1 to 2 @ 20mph around 3k rpm, then to 3rd around 30-35 mph. My old tranny shifted sooner than that. It's killing my mileage. Does a higher stall convertor change where it shifts at all or does it just make it rev higher?

 

Just adjust your TV cable. It's not set right.

 

he has a <b> with 9.5" TCS 2800 stall convertor! </b>

if your old tranny was stock and your new one has that converter, theres your reason right there.
Do you have lockup? If not theres half your fuel economy right there. a higher stall will make it "feel" like its shifting later (rev higher) because it has to spin the engine up a bit more to get the car moving. this is the nature of high stall converters. if you dont need such a high stall (i.e. your camshaft does not demand an engine idle of 1000 rpms) then its totally un-necessary to have a high stall on the street. It doesnt hurt for launching though...

How baddly did it hurt your fuel economy, and do you have lockup?