Transmission Ratio Progression

Here's what I have:
2750 # Promod
518" KB Blown Hemi
Bolt together Chance converter
3 Speed Lenco 31 % & 50% making a 1.96 Low Gear

Here's my question. Which progession of gears would I be better off with:

1.96 - 1.50 - high or 1.96 - 1.31 - high

Until I pulled my trans apart a couple of weeks ago, I thought that I was using the 1.50 for second but realized we had it set up using the 1.31. We were shaking the tires in second pretty much all year. I'm wondering if it was bogging the motor and that's why it was shaking the tires. I had also noticed that I could run with just about anyone in low gear but seemed to fall behind about a car length immediatly after shifting into second. I also broke two sets of the 1.31 gear sets.

It seems logical to me that if I use the 1.5 second, it won't be such a big drop and might help the tire shake and could actually run quicker. It hopefully will be a little easier on the gear sets also.

I've got one race left this year and can't do any testing ahead of time so I 'm looking for some opinions.

Thanks,
Keith Goolsby

 

You need a tighter ratio to keep rpm drop to a minimum to keep the boost up. I'd run a 1.31 x 1.31 and run more gear in the rear or give it more timing at the hit. I assume you're pulling timing at the starting line now?

 

2 speed drops the rpm too much, that would magnify the problems you are currently having.

 

Most of the guys that I know that are running a converter use a three speed and run really well. Our converter is generating some pretty serious heat right now. I think that going to a two speed would only make that worse.

I don't have the parts to change any of the ratios right now so which do you think is a better progression using what I have ?

1.96 - 1.50 or 1.96 - 1.38

Thanks,

Keith

 

Well I'm no expert by any means , but I'm running something very close to what you are doing . When we had the 1.95 witha 1.45 second gear the car ran with no big drop off in either power at the shift. So I tried the same gear 1.95 but with a 1.35 in second gear and the car fell on its face with almost 2300rpm drop at the shift . Now were are getting parts to go to a 2.10 (1.45*1.45) . Hope this helps !

 

Thanks guys, that's what I was looking for.

The 1.45 - 1.45 deal sounds like the way to go. We may change to that this winter. I'm going to try the 1.50 second this week and see what happens.

Thanks,

Keith

PS. I'd still take any input/experience anyone else might have

 

That's a lot of first gear for a converter deal. Ben there done that. But to each his own.