Converter flash
 

Does a gear change affect converter flash ? Say going from 5.13 to 4.88 or 4.56 to 5.13

Re: Converter flash
 

Yes it will. Not a lot, but it will change. It’s just like adding weight. Everything being the same the converter will flash higher with 4.56 than a 5.13. You may not see much change either way with 4.88.

Re: Converter flash
 

Thanks

Re: Converter flash
 

I went from a 4.30 to 4.88 and lost 300 on converter.

Re: Converter flash
 

Jeff,
How many did the slippage change on the top end?


Stan

Re: Converter flash
 

A different low gear Trans ratio will change stall but not the % slip on top end.
A rear gear will change both stall on the leave and slip down track.

Re: Converter flash
 

Adger, in your experience How much will it change going from 2.52 to a 2.75 1st gear?

Re: Converter flash
 

Thanks Jeff. What I was looking for on rear gear changes.

Re: Converter flash
 

Jr, Can't really put a number to it. too many variables. small engine vs large engine,... where in the Tq curve the original stall was, ect. Each application varies. Change the gear, check it with your original converter and make changes as necessary. Like it has been said before... change one thing at a time and test. Your new gear may not like the stall the other set up liked. Don't forget about the low to second % gear drop may change. That may be where you need some help from a converter. Good luck Test, Test...

Re: Converter flash
 

With gear change the data logger showed the finishline lock up went from 6.5 to 5.5. I liked that part but not the .05 loss on 60ft.

Re: Converter flash
 

There are many variables such as the RPM drop between 1st and 2nd gear. Also, you have to take into consideration the engine power band.
An engine with a narrow power band, does not like to have a big drop between gears since it makes it more difficult to recover.

I worked on a Stocker that was quicker with the OEM 2.52 1st gear than the 2.75 1st gear. The engine had a narrow power band and the RPM drop between 1st and 2nd had a high percentage of RPM drop.

Nowadays, with the advent of transmissions with a high selection of gears, it makes it easier to optimize 1st and 2nd gear ratios to match the power band of the engine.