I have a ford 9" under my 72' GS.... How strong are the stock gears 4:10's and 29 spline axles. At what horspower or ET does this stuff break...I am also wondering about driveshafts..I got a new drive shaft when I put the 9" in two years ago, but how stong is a replacement driveshaft. I have a new motor that is going to stress this stuff, I will be getting new axles with a full spool so don't worry about that..just want to know about the other stuff. Oh yeah..um er I also have a th350 that has work done to it to supposedly support the motor, but what is gonna break there to. thanks guys josh
hey josh, i use a moser 9 inch in my 72 but dont have big horsepower. here is what i know-when buying your new axles and spool, go up to the 31 spline stuff-it will hold big horsepower allright. DO get a custom driveshaft-they aren't that expensive. I have richmond 3.89 gears, moser axles and a detroit locker-10 years, 40,000 miles, maybe 150 passes in the low 13's-no damage can be detected at all on any of the components. i also have had no problem with my th 350 and as an aside, bruce kent (2000 and 2001 winner at the nats in bowling green, 2 different cars) uses a th 350 to run 10.40s in his 70 GS, the white one he won with at bowling green in 2000. higher stall speeds or a trans brake are what will usually accelerate wear on the differential parts. ask a die hard stick shift guy about his differential maintenance. hope this helps
If you're buying axles and a spool, why no go all the way and buy 35 spline? More strength, and about the same money I'd think.
Hi Guys, I agree with Adam, I have a Moser 9" with Currie built Strange center section w/Richmond gears and 35-spline Detroit Locker in my '70 GS455 4-speed conv. Also use a Denny's "Nitrous Ready" 1350 series driveshaft. BTW......the stock 9" came equipted with either 28 (light-medium duty) or 31 (heavy duty) splines........
The 31 and 33 spline axles and spool were the same price when I bought mine. The 35 spline won't fit with a standard bearing case. The 33 spline spool was not available when I got mine, so I had to get the 31 spline to make the next race. That was 6 years ago with a nitrous 462 stage 2 in a 3850lb. car. I have never hurt an axle or gears, but the stock center section gave up last year, literally blew apart, pinion flew out the side and came to rest on the gaurd rail with the driveshaft hanging in the safety loop, pushed the ring gear through the housing. Good news is, the drive shaft lived and the axles were fine, after a service on the driveshaft (Denny's) a new set of gears a new center and a patch job on the housing I made the next race. Bad news, I was in the later rounds of a $5000 to win race, had a better light on the guy and he was the eventual winner. Car made it about thirty feet, luck has alot to do with racing, the rear could have let go at any time, over 5 years of use and it decided to go at that point, if you don't buy the parts you need you will pay in the end. Spend the extra money on the nodular housing and get the biggest axle that doesn't cost more money.
Hi Dennis, You say your stock center section fianlly let go. Did you have a nodular center section? (Might have to use my "spare Transmission" this year as mine is giving me problems). Are you still using the switch pitch?
