rear gear swap info

[Bonnewagon]

I have only bought 1 set of gears brand new and they were from Richmond and they were great. I actually use GM gears when I can find good examples at swap meets or when I am lucky enough to bump into John from Gevo's gears. http://rearsgears.com/ He sells mint used gears and even once hooked me up with a set of gears and posi carrier for my '68 Buick LeSabre. The factory manual has specs for used gears and bearings so no worry about durability. For severe duty you of course would want new racing quality gears but I expect stock GM or any brand to last forever when set up correctly and the lube maintained.

 

[mebe007]

I always hear bad things about running used gears

 

[Bonnewagon]

Bad things happen to people who fiddle with rear ends while not having the tools nor the talent. Hey, my first gear swap I got about 15 feet before all the teeth broke off, and then I studied and learned. Now I can take a totally worn out set of gears and make them work quietly, so don't believe everything you hear. All that matters is that the ring and pinion gears are firmly held in suspension by pre-loading them enough so that the driveline torque can't move them out of alignment. Then if the backlash and tooth contact pattern are correct, they will work quietly and last a long time. Of course it is always best to start with new everything, and if a professional shop was doing the work that is what I would specify. But that is not always possible nor practical. I would not want someone to be building a rear for the first time with $1000 in new parts. I would want them to practice with used parts, just in case. (wink wink, nod nod)

 

[mebe007]

You need a Vaca to VA. I'll buy the beer and steaks lol

 

[Bonnewagon]

Yes, I DO need a vacation. Ha ha. And as the weather cools I will be fishing my *ss off. I promised my Grandson a Striper and so far no luck. Anyway 3:90's are a little extreme unless you race a lot. My buddy went with 3:73's and curses when he has to travel any distance. Now he wants overdrive but can't afford it. You are correct about the 10 to 1 overall ratio, it makes life easy. I hate riding the clutch just to get going. So if you do the work yourself, and there is no reason not to, then I would grab some nice lightly used gears cheap and try installing them. Then if you want more gear, go ahead and try a different ratio. Used gears are cheap, $100 or less. Then when you are satisfied, and experienced, go ahead and get some expensive high quality gears.

 

[mebe007]

I did the math and with a 275/60/15 60mph cruiserpm was like 2800 and with 3.73 it was like 2600. Neither seemed too extreme. The new clutch that's on the way is a 6puck ceramic disk which can tend to be an on/off switch so I was thinking maybe the lower gear would ease some extra driveability into it. I don't race much anymore but hope to make it t track lol. Just a few miles up the road to the show or through the country. Don't know that I would attempt Carlilse next year even with the 3.42 so it will probably get trailered on long hauls.

 

[Bonnewagon]

Ahhh, OK, that's a tall tire, about 28", really knocks down the ratio. Does that disc have a marcel? That's the springy thing around the hub that absorbs the shock of engagement. Without it that's going to be some harsh b*tch to drive!

 

[mebe007]

Its a sprung hub but has no Marcel. The gear swap has to be really worth it overall for me to commit to it. Right now she's sitting on 255/60/15 (27") but I've got the 275/60/15 (28") nitto drag radials sitting in the shop mounted on rally wheels

 

[Bonnewagon]

Right now I am using 225-75-15's on Pontiac RallyII's. With a 2:73 rear I am cruising 60 mph at a leisurely 2000rpm. Talk about loafing along. But my 3:50 first gear Saginaw knocks it all down to a nice 9.55 overall ratio. Kind of a poor man's overdrive just as GM did it before overdrive became common.

 

[pontiacgp]

Right now I am using 225-75-15's on Pontiac RallyII's. With a 2:73 rear I am cruising 60 mph at a leisurely 2000rpm. Talk about loafing along. But my 3:50 first gear Saginaw knocks it all down to a nice 9.55 overall ratio. Kind of a poor man's overdrive just as GM did it before overdrive became common.

That is a sweet gear, GM has been using the 2.73 gear in the corvettes. You have your car set up really nice, how did you find those gears. I had an easy time with a 5 speed.