Reverse Rotation Boxer Engine?

[prova]

Hi guys this might seem a bit of a 'random' question but has anyone had any experience or knowledge of reversing the rotation of an Alfa Romeo Boxer engine? Looking into the possibility of fitting the engine into my FIAT 850 Coupe - these run counter clockwise.

The other option is to use the Alfa box and driveshafts as well hence my second question - is it possible to 'flip' the final drive in these boxes - I have heard it can be done - does anyone know if it can be done?

I have been mucking around with an AMR500 supercharger and a 903cc FIAT engine but the boxer engine would be fantastic. I have owned two Sprints before and the engines have left a big impression on me. For my application they have a lot going for them - short and weight down low being some of them.

All the best, Ren.

[jayarr]

Hi,

often thought of the same, never got beyond the dreaming stage - best of luck!

Cheers, John

[meizhak]

Prova,

Have seen a VW gearbox Fitted to a 850 with twincam fiat engine. Very fast indeed.

Meizhak

[jayarr]

Hi,
would suggest asking Beninca's or Italian Job. Seem to recall someone mentioned flipping the diff in the alfasud box was a possibility.
John

[Frank Musco]

Ren,

Reversing the rotation of the boxer engine is something I have not heard about, but, not saying it can't be done.
You would need to get the camshaft timing changed, no big deal.
Change the way the cambelts are tensioned, which may need the water pump moved/rotated?
Fit the pistons so the offset is opposite to original, easy.
Make a gear for the back of crank to make oil pump work, then pump drives the dizzy, so gear must be very specific for correct timing.
Get a starter that works the reverse direction, and meshes with flywheel. Modify original?
and it's starting to get expensive, and that's without looking at it...just initial thoughts.

Flipping the diff in the gearbox seems the way to go, but that also is not as easy as it sounds. I haven't heard of that either, and I can tell you it cannot be done by simply removing the diff center and 'flipping' it around and refitted and away you go. It won't fit. Tried it.
The problem is the clearance required for the crown gear side of the diff. So when flipping the diff, it ends up on the side where the speedo gear/sensor is fitted. Therefore, the speedo side, inside the case, will need to be machined away for clearance. Then you loose the speedo. There is a possibility of machining through the front of the case. Not a big problem. You would also need to use the early model Sud sump, that's the easiest part. Drive hubs can be swapped, and shimmed to get proper crown-pinion mesh, easy. I would definitely give it a go. Get the angle grinder out! 

The photos show the diff in correct position, then flipped and not fitting, and the speedo section encroaching in the required diff space, and the side with the original clearance required for the crown gear.

[Ray Pignataro]

Why not just mid mount the boxer motor and gearbox in situ. not disimiler to the v8 powered sprints

[prova]

Frank your a legend - great post thanks for your awesome input!

[Frank Musco]

Why not just mid mount the boxer motor and gearbox in situ. not disimiler to the v8 powered sprints

Yes Ray, I'm assuming that Ren wants to use the 850 coupe as a road car, therefore requiring the rear seat, which would have to be removed for your suggestion. If it was to be a two seater, definitely that would be the way to go. I love it. Mid mounted boxer, gearbox out the back, low center of gravity and further forward, so many positives.

Ren, time to cut the rear seat out!

[prova]

Thanks everyone for your posts. The car will be running without a rear seat, carpet, headlining, etc - partially stripped but still a road car. My idea is that I want something I can drive to club level events in, hillclimbs, sprints, etc. Mid mounted would be excellent but it would be nice to retain the original orientation of the engine for 'sentimental' reasons, simplicity and for engineers approval.

We are building up a supercharged 903cc engine at the moment using a Ducati 50mm throttle body and fuel injector, and associated electronic control but I would also like to source a complete 33/sud/sprint and have a look at flipping the final drive for the future either for my car or maybe a second car.

If anyone has any further info could you please post it up as it is very much appreciated.

Ren