CLASS RACER FORUM - 4-spd Transmission Choice for lower class Ford US/VS/WS cars

Quote:

Originally Posted by Greg Reimer 7376 (Post 512072)

How in the world would you break a 9 inch with a Pinto motor?The 8.8 would be the logical choice due to size,weight,cost and availability. If 6.14's are available, so would anything else you would need.The 8.8 uses some of the same internal bearings as a 12 bolt.It would definitely be more low friction than the 9 inch.

Greg, Of course the 8.8 would seem like the logical choice. However, all the different ratios were not available (in the 5. -- range anyway) last time I looked into this.
However, if a 6.14 is available, here's what I came up with.

First of all, I try to set up a class car to be able to run 9-10 under.
That way, it leaves room for improvement if you don't have the beans under the hood to run that at first. At least you will know where the problem lies.

So, W/Stock is a 16.40 index.
Let's shoot for 15.50. I know that you will have to run pretty close to 85 mph to go that quick.
Using a 26 x 8 MT tire, and a 6.14 gear, 7000 in the lights would be about 88 mph.
Trust me ..7000 is not too high for a non turbo 2300. Probably not high enough.
With the 6.14's , at that weight , you wouldn't need a super low first gear. Just a bit of flywheel weight to carry it out smoothly, and all the rpm you want.
That's my take... FWIW