I switched to polished gears, coated bearings and the aluminum spool. All those together we picked up almost .03. From 3.121 to 3.092 and 1 full mph. 103.3 to 104.4 repeatedly. Very happy with the whole thing. Single 4 all motor sbc qualifying in the middle of a class dominated by 500" blown alcohol cars. One more tenth and we will be winning the big money. Please pass the prune juice.
The same. The pattern dictates the lash. You can see I like it just inside of center. Any deflection at all will push the pattern to dead center on the tooth. I'm thinking this one ended up at .0104" lash average taken in 10 locations.
Not true! We have a lot of Super stock type cars (3000+ lbs) ruining a our 35 spline spool. The 40 spline spline spool are used most everything else. And we do recommend using the 40 spline if it will fit your rear. Our 11" Modular rear with indefinite gear life uses a 40 tooth aluminum spool. All the M/W aluminum spools are produced from 7075 heat treated forgings. Not 6061 that some manufacturers utilize.
I would agree with Mark @ MW on this. We have been running MW Aluminum Spool in a few Ultra street cars. One of them is a Pro Charged @ 3350, with 1.16 60ft. The other is a NOS car @ 3150, with a 1.19. The best part of this deal is the weight savings 4.5lbs in the spool. And The hole package with lightened Gear and Titanium studs, & Aluminium 1350 pinion Yoke with the 40 spline Gundrilled Axels,They saved a total of 22lbs over the steel spool with 35 spline Axels. It's crazy... IMO Ultra Street & x275 reminds me of a max effort super comp car. Trying to get every bit of ET out of the combination. The fields are so tight. One last thing, MW also offers a ceramic wheel bearings, & Pinion support bearings, setup for low drag...
How much does tire choice, radial vs. slick, 28 vs 30, etc play into when a person should no longer look at an aluminum spool? If a person is already needing to purchase a new spool, the cost for the weight savings is worthwhile.
I assume you are using a 9” Ford type rear. The 40-spline spool would work for your application. We use the 40-spline spool in applications including the 11” Pro-Mod rears that have the 40-spline aluminum spools.