How to mount a secondary transmission backwards for added gears?
 

Please, I thought of this years ago, but could not figure out how to do it?

Dan Merritt

More details please.

If you mount it backwards, doesn't that mean you're stepping the speed back down?

No, it would be a super-duper overdrive, depending on the transmission.

Perhaps it could function as a poor man's Gear Vendor's OD?

I knew i read that somewhere. Xpedro did that on the Aerosprite.

http://ecomodder.com/forum/showthrea...ent-28086.html
It wound up with a 1600cc pinto engine (& transmission) with the camshaft retarded 2 notches (poor man's Atkinson cycle)
Additional (2nd) Buick transmission, reversed, to gain up to a 2.5 overdrive

Reply to backward transmission.
 

I guess it would have been better to write it out than assume everyone would know what I was talking about.
It is the Aero Sprite by Tom Shrimplin, who modifies an Austin Healey Bugeye to get 65 mpg by modifying the body to very aerodynamic, installing a 1600 Pinto engine with a 4 speed PLUS A BUICK TRANS MOUNTED BACKWARDS GIVING THE CAR 12 FORWARD GEARS.
OK, now that is the background, now, how do you accomplish this feat, Tom, anyone?

I understand what you're asking, but if you sit down and really think about actually installing a 2nd transmission, it's a ridiculous concept. Wastes energy, extra weight, complexity, reliability issues.

Besides, the 65 mpg that the Aero Sprite achieved is not all that impressive these days.

I thought that was interesting (with appropriate caveats) when I read about the aero-sprite too.

dtmerritt, your car might be suitable for a $20ish, 1 hour to install, 5th gear swap.

But otherwise I'm guessing the buick was a 3 speed, so you would have to look at the pinto 4 speed and the buick 3 speed from that era and figure out the nuts and bolts. If the pinto 4th gear and buick 3rd gear are direct drive, it might not have been too "lossy".

The streamlined Ford Model T also used the "backwards 2nd transmission" trick: from a Chev, installed behind the Ford's:

http://ecomodder.com/forum/showthrea...odel-t-92.html

http://forum.ecomodder.com/attachmen...1&d=1199032408

The vehicle I want economy from is a 1955 Pontiac Star Chief ( almost 4000 lbs and square as a brick. It has the very old dual range Hydro Matic without a park position. Economy is one factor, another is, who knows how to fix it id it breaks?

Van get a $800 adapter and put a GM overdrive trans behind the engine for about $2500 Total, will pay for it,self in 40,000 miles.At 69 and with various heath issues, driving 5,000 miles a year, that is a chancey bet.

I could put a Gear Venders OD behind the hydromatic for about $3,500, then I still have the worry of the original trans.