Selecting Rear End Gear ratio

[Stan Weiss]

My post from a thread on another forum.

Stan Weiss wrote: ↑Sun Dec 13, 2020 12:52 am



Remember et is from early in the run and MPH is from the end of the run.

I number of years ago I did a simulation of an NHRA Pro Stock motorcycle. I was off some but the engine builder / crew chief looked at my inputs and gave me some gearing and HP and Torque changes. I then hit the different times and MPH. I said to him the only way I can get that et with that MPH is to run out of RPM before the finish line. His answer was me too.

Stan

Does method work with your Stock or Super Stock car?


Stan

[SSDiv6]

Originally Posted by Stan Weiss

My post from a thread on another forum.

Does method work with your Stock or Super Stock car?

Stan

When Pat Hale was developing his Quarter and Density prediction software programs, he ran into the same. I supplied him at the time lots of data from Stock and Super Stock cars. Since at the time he was racing in Comp Eliminator, he was also gathering data from the class.

At the time, late 1980's and early 1990's, he was able to get close on the predictions with the software. Then, with the later new rule changes and performance improvements in both classes, it was back to page 1.

[Billy Nees]

Originally Posted by Stan Weiss

My post from a thread on another forum.





Does method work with your Stock or Super Stock car?


Stan

I think that you'll find that that is what S/SS Racers call "airing-it-out".

[Croozin2]

Really enjoying pouring through all of these tech topics as I’m hoping to return to racing this year in B-C/SA. Was in outboard racing for several years in the 80’s-90’s and this is exactly the issue we ran into there. In order to make the boat leave and “set” quickly, you had to reduce prop or raise gearing. Obviously, you were running the guts out of it (7200-7400 on a stock powerhead) to try to hang on at the finish.
We ran the current car (96 LT1 Camaro) several weeks ago and the car is just a turd at 60’ but runs the mph. Car was purchased running as is so need to run through it and verify gear ratio etc. So, listening to you guys discuss this, I guess in order to get everything else in line, I should be prepared to run out of gear prior to 1320.

[Mike Pearson]

There is not much ET made in the second half. The short times are what you need to work on.

[Mike Rietow]

This is a 845 SLR 1.69 low gear 3200lb n/a 23 sbc on a 10x28 bias 2400 d/a SGMP.

I'd like to see what she could do on radials in some good conditions, although I don't believe she'd pickup as much as some of have on radials. Might go low 1.20 though.

This is a engine & transmission I assembled, all steel Nova front & back seat delete. Transmission Specialties spragless converter B-crcxls. Ran like this off the trailer new.

3.875 x 4.185 Brodix T1 233 out the box, Bullet rollerstick.