Hello all
this is my first year as a member in this project. our team, as well as many other teams, uses motorcycle engine. our engine is installed the same way as it is installed on the motorcycle, which means exsust pipe in the front side and carbs on the back side. why not turn it around(similar to the cannondale off-road motorcycle...)??? is there a team that did it? can anyone think of a reason not to do this?

Then you'd get 5 reverse gears and 1 forward gear.

so you reverse the spin from the engine, not too big of a problem.

I believe Michigan Tech did this a few years ago. I think they want as far as spinning the engine in the opposite direction. This included making a new impeller for the water pump and new cams. I'm pretty sure it was a dry sump with an external pressure pump. Its been a long time though so I could be completely wrong on the details of how they did it.

Auckland, NZ did it last year, and took the car to Germany. I'm not 100%, but I believe that they haven't changed the layout this year.

Hope that helps

We didn't exactly reverse the engine. What we did was tilt the engine backwards, so the sump became near vertical, the headers went up and the intake downwards. T

his set up lowered the COG by about 50mm and allowed us to lay the driver back (dropping their COG) as the engine fits better into the car.

But it's not all cream. The oiling system is of no real use, but if you come up with a sweet dry sump that will over come this.

I think that MTU just changed cam timing and ran the intake through the original exhaust port and the exhaust through the intake ports. Then the only thing that needs changing is cams.
Bill

Just flip the head around backwards...

Billy
That is only possible with a centered cam drive. I think this was a feature only on suzukis, but could be wrong.

quote:

Billy
That is only possible with a centered cam drive.

That's true, but this was a Yamaha FZR. Not sure about the Suzuki. It wasn't really as easy as just turning it around backwards...

yep,
thats the engine that I was thinking about.

I doubt this would really work because of the speeds but it might. When I was looking into doing a reversed 4 cylinder I looked immediately at the crank to main shaft setup. Typically they are all geared. If one where to take the crank and hob the counterweight with gear teeth for silent chain teeth and do the same on the countershaft gear. That change would do what you are looking for and not change much else. But why would you bother when you can run a single and run FTD's and make the car that much more simple to begin with.

why would you not be able to flip the head around backwards on a non-centered drive head? this is of course assuming that there are no tensioner mounts and the oil passages are symmetrical... just keep the same cam orientation and flip the head.

Parker,
How would YOU run the cam cahin from the crank sprocket on one side of the engine to the cam sprockets on the other side of the engine on a non gear centered head?

From what I can see, our GSXR head has been line-honed from one end to the other. What I am saying is If you were to flip the head around, and THEN flip the camshafts around so that the gears were mounted in the head on the same side of the engine (opposite side of the head) as they used to be, would this not work?

Problem is most of the heads have a buiilt in section for passing the chain through. If you flip it the opening for hte chain will not be there, and you will have to pass the chain outside of the engine casting. There is no guarantee that you would be able to align the sprockets anyway.

As for the non-centered cam gears, the bes t option would be to change the flow to be opposite. This would involve haveing custom cams ground, and either fixing valve and port sizing, or neglecting that all together.

Just FYI, the center driven cylinder head was no easy task to flip around backwards... Yamaha made it interesting by offestting everything 1.5mm instead of being nice and symmetric. We also had to do a lot of welding and machining for the chain to clear once things were flipped around backwards, as well as having custom cams ground. It ended up being a whole bunch of work. In 05 the Detroit judges thought it was great, but in 06 the Fontana judges thought it was pointless... This year we're moving to a different engine, so we won't be flipping things around anymore.

I was not on the team when Michigan tech did the backwards motors (they did it for like 4 years) but I have seen and studied the cars a bit) They ran the motor backward which required:

Modify the water pump to work backward

At first modify the stock oil pump, eventually ran a dry sump with an external pressure pump

Cam chain tensioner moved and modified

There is an anti-backlash mechanism in the primary drive gears that had to be modified.

I believe the cams were symetrical so it was just a matter of getting the timing worked out

Modify starter motor to work backwards

Packaging is great except for the chain, which had to be far off toe the side to get around the motor, so one cv shafts was very short, I'm not sure if torque steer was a problem or not with the chain so far off to the side.

Probably more that I don't remember or never knew about.

This is not to bash the guys posting here, but why bother??? There seems (IMHO) to be 0 advantage to flipping the engine around or upside down or whatever..... so why go through the extra work? I dont see the point of modifying something that heavily 'just because you can' or whatever.

quote:

This is not to bash the guys posting here, but why bother??? There seems (IMHO) to be 0 advantage to flipping the engine around or upside down or whatever..... so why go through the extra work? I dont see the point of modifying something that heavily 'just because you can' or whatever.

By flipping the head, we were able to package the supercharger, intake and fuel system (all the heavy stuff) nice and low and allowed for a good alignment for the supercharger belt. The exhaust (pretty lightweight) was the only thing high up (see the picture). It also kept the hot exhaust away from the driver and the fuel system.