I've read here that raising the stall speed will actually lower your cruising RPMs a few hundred. Think it would be enough to offset the increase in RPMs you will get from the 3.9 final drive, giving you no loss of fuel economy??? Oh and by the way you should loose about a second off the 1320 with these two mods...

 

This is heavily dependent upon the quality of your launch and the traction of your tires. An upgraded TC and shorter gears are similar to a lightened flywheel in that they increase theoretical acceleration while reducing the margin of driver error. If you are a good driver equipped with some sticky rubber, I'd venture that 1 second could be knocked off.

 

Count in the extra shift you may have to plug in, if you run out of 4th...

 

Oh sorry,this is auto we're talking about.... nevermind, not sure if same logic applies, but one thing for sure -- all gears shorter.

 

ok dont flame me to bad cuz im new to the modding scene. cant you just get your ecu reflashed to lower your RPMs. this way you dont have to shift as soon

 

well, you cant do that but you can raise your rev limmiter, but that won't help you on this car, maybe a honda. I don't know correct me if i'm wrong./

 

I am assuming you are talking about shift points and/or rev limiter (neither of which make sense given your comment). The ECU can not control the actual rpms that the crank is turning in relation to the rest of the drivetrain. It can control ignition, A/F and timing which can affect how fast the rpms climb. Wouldn't matter at cruising speed anyway because you would be in 5th gear already and have no more gears to shift up to. In town you can use manual mode to control shift points so modifying the ECU for this purpose is not really necessary. I am not quire sure what pieces of info are actually in the ECU vs the control unit for the 5AT either. It may not be possible to even adjust shift points in the ECU.

 

no one answered my original question.

(I've read here that raising the stall speed will actually lower your cruising RPMs a few hundred. Think it would be enough to offset the increase in RPMs you will get from the 3.9 final drive, giving you no loss of fuel economy??? Oh and by the way you should loose about a second off the 1320 with these two mods...)

 

The only way a new TC will yield lower rpms at any given speed is if it is more efficient than the stock one. I have heard claims of this but no one has backed them up so far. This should be demonstrated on a dyno as well since you would be in affect increasing the HP and TQ curves against the rpm since less power is being lost due to the TC's inefficiency. As soon as someone can prove to me this is what is occurring with some of these custom TC jobs, then I am all over it. I do not simply want an increase in the stall rpms as that is really only a good thing for the 1/4 mile, but an increase in TC efficiency is a very good thing.