PINTO CAR CLUB of AMERICA

Welcome to FordPinto.com, The home of the PCCA => General Help- Ask the Experts... => Topic started by: boresracing29 on April 28, 2012, 11:20:43 PM

Title: gearing questions on a Pro-4 race truck on 1/4 mile asphalt ovals
Post by: boresracing29 on April 28, 2012, 11:20:43 PM

Not actually a pinto, just pinto parts on a pro-4 race truck.  Have a question if someone out there can get me an answer.  I have a transmission with a 2.14 second gear with a 7 1/2" rear end that has a ring and pinion 3.73 gear.  I run on a quarter mile flat asphalt track and am getting beat down the straights (need more off the corner.) Would changing the rear ring and pinion gear to a 4.11 get me what I need? and also would I need to change tranny to one with a 1.97 2nd gear ratio?  Max rpm with what I have is @ 6500.  Would this combination put me around 7500 rpm.  Run a 15" x 8 Hoosier tire. The engine I have is the 2.3 liter.  Engine builder said he had it at 8300 on the dino if this additional info helps you to answer my questions.  Any help would be appriciated.
Title: Re: gearing questions on a Pro-4 race truck on 1/4 mile asphalt ovals
Post by: 82expghost on April 30, 2012, 12:23:23 AM
do you want to leave it in one gear or do you shift, 1st is useless ofcorse and are the other guys down shifting when they go into the turns? whats the bank like? what speed can you take the turns?
Title: Re: gearing questions on a Pro-4 race truck on 1/4 mile asphalt ovals
Post by: 71pintoracer on April 30, 2012, 08:06:36 PM
So many unanswered questions....j ust because it turned 8300 on the dyno doesn't mean that's where it made the most power. However, 7500 is no problem. When I raced my dirt car I was turning the 2300 7800-8000 all the time. These motors are super tough. As long as you can get the power to the ground your good with the 4:11 and I wouldn't change the tranny just yet....one change at a time.....or you'll never know what worked or didn't work. Once you get in the ballpark with the gearing you can play with cam timing to fine tune getting off the corner.