Taller gearing, axle or gearbox?

[Ratty]

Hi all, quick question for you;

I've recently fitted an 8 lug '87 Burb rear axle with 4.11:1 diff gears (Think you chaps call it a centre-section) into my '63 Panel in the hope of gettting better gas mileage and cruising speed but she's still a bit revvy at 70mph. Are the crown wheel and pinions in these axles interchangable with other Chevy axles (For instance Camaro) or are they specific to the 8 lug? Sure would be helpful if they are as we don't exactly have yards full of old Chevy's in England!

By the way before anyone says that 4:11's won't give me taller gearing anyway can I point out that my stock axle had something near 6..2:1 gears in it!!! Originally the truck had a straight 6 backed with a 3 speed column shift but is now running a 350 with a 4 speed floor shift.

The other option is to find a 5 speed box with a nicely overdriven top gear on it, any recommendations?

Thanks in advance, Ratty

[blackedoutharley]

Taller tires (tyres).

[VWBeamer]

Love your truck.

A OD transmission would allow you to keep the the great acceleration the 4.11 offers.

[62 mark]

I am installing a Borg Warner 5 sp. trans. in my 62,pretty much a bolt in swap, with driveshaft mods and such.However i am running a 6, and these trannies are not rated for very high HP motors. I do have the world class unit that was out of a camaro v8,I think it will handle a 283 v8 .

[Captainfab]

That '87 Burb differential should be some form of a GM corporate 14 bolt. It will be either a semi-floating, or full-floating differential. The only gears that will fit, are from another 14 bolt of the same type.

You could purchase new aftermarket gears, in a ratio of your choice, but installation is not a simple procedure. The other options are taller tyres as blackedoutharley said, or a OD trans as you and 62 mark said. I guess that decision will partially be determined by what is available over there in England.

[Ratty]

Thanks for the swift replies guys

Captainfab; thanks for the info, I kind of figured it wouldn't be as simple as I hoped! 14 bolts pretty hard to come by over here and I'm guessing a new gear-set isn't exactly going to be a cheap option either. Think I'll discount that idea then.

Blackedoutharley; taller tyres would be a simple move but the ones on it now are pretty tall as it is and taller ones still may well give me clearance issues. Worth a meassure up though.

So a 5 speed sounds like the best option all round. There's a few to choose from over here that might do the job, for instance I'm fitting a ZF 5 speed from a Bedford CF truck behind the Cadillac Flathead in my Model A Modified project, so I think I'll ask about over here to see if there's a UK market box that will be a simple-ish fit.

Out of interest I've heard good things about the box from a Chevy S10, would they be up to the power from a stock-ish 350?

Thanks again, Ratty