Honda S2000 Transmission

[johnc]

Does anyone have access to a S2000 transmission for the purposes of obtaining dimensional data?

Locally the only savage yard that has one will not, for insurance reasons, let me into the yard for any time to make measurements. I was able to get a brief peek at it, and it appears the dimension from the front integral bellhousing face to the point where the shift rod exists the casting on its way back to the shifter is approximately 16". That being the case, then it may be possible that the S2000 could be adapted to an Elan.

If someone could flush this out I would be appreciated.

[RotoFlexible]

Do you mean Honda S2000?

I don't have access to one but you reminded me of something. A while back, this post sought information about a Twin Cam crankshaft. The poster runs a race prep shop that specializes in Honda S2000s. Looking through his site (http://www.RaceLabz.com), it's clear that he knows his way around the box and also conversions (e.g., S2000-powered Miata). And he has transmissions. If someone's in the vicinity of Swoyersville, PA, perhaps he could pay a visit and see if Dan has any interest in Elan conversions to use this box. Or someone on the US >4-Speed Committee could drop him a line.

[johnc]

Yea, I apparently didn't have my head screwed on correctly this morning. Should be Honda S2000. I edited the title to correct the error

[1964 S1]

Do twinks and S2000 engines rotate in the same direction? And now that I think about it,,,, what determines an engine's rotation direction? Is one way better than another?

[john.p.clegg]

Not completely sure of this....... but.............engines destined for the Northern Hemisphere rotate clockwise............Engines destined for the Southern Hemisphere rotate Counter clockwise........

John

[fatboyoz]

Not completely sure of this....... but.............engines destined for the Northern Hemisphere rotate clockwise............Engines destined for the Southern Hemisphere rotate Counter clockwise........

John

Sorry John,
Southern Hemisphere, definitely clockwise.
Colin.

[hatman]

Sorry John,
Southern Hemisphere, definitely clockwise.

Is it the same with your bathwater then?

[garyeanderson]

Do twinks and S2000 engines rotate in the same direction? And now that I think about it,,,, what determines an engine's rotation direction? Is one way better than another?

All Honda NEW engines rotate the conventional way, the V6 engine have always done so and the 4 cylinder engines do so starting with the K20A (S2000 engine) and the continuing with Acura RSX and now the new Honda Civics . If you were to use the honda S2000 gearbox, it would be better to keep the S2000 engine with it and save on the adapter plate that assumes either or both would even fit.

the gearbox weighs 95 lbs engine and gearbox are around 375 lbs.

http://www.usa7s.com/aspnetforum/Defaul ... sts&t=1725

Honda engines that rotate the opposite direction are the B and H series that were designed exclusively for transverse FWD.

[johnc]

If I got this right the S2000 is not the overdrive transmission that we desire. The 2nd generation gear ratios are:

1st 3.133
2nd 2.045
3rd 1.481
4th 1.161
5th 0.943
6th 0.763
Reverse 2.8
Secondary Gear Reduction 1.208

So what is this secondary gear reduction. Apparently it is and output gear set within the transmission housing which shifts the entire transmission gearing. That is: transmission (gears 1-6 + R) --> secondary gear reduction --> driveshaft --> rear diff.

That being the case, then the effective 6th gear ratio is 0.916 (I.E. 0.763 * 1.208).

So unless one can change the secondary gear reduction ratio, the S2000 is not a suitable candidate for a US solution. I should have noticed this prior to starting this thread of discussion.

[GrUmPyBoDgEr]

Classic, John PC, just brightened my day, a good start to the week
John

[RotoFlexible]

So what is this secondary gear reduction. Apparently it is and output gear set within the transmission housing which shifts the entire transmission gearing. That is: transmission (gears 1-6 + R) --> secondary gear reduction --> driveshaft --> rear diff.

The Honda press release that goes into maximum detail about the transmission (and the comparison of 2003 and 2004 models) is here but it doesn't shed much additional light on this question. Neither does the Honda marketing information for the current S2000.

[Frank Howard]

Honda engines that rotate the opposite direction are the B and H series that were designed exclusively for transverse FWD.

As a side note, I have noticed that unlike the majority of modern transverse FWD cars (I'm excluding the original Mini), these counter clockwise rotating Honda motors are mounted on the left side of the engine compartment. When Honda switched to clockwise rotating engines, they began mounting them on the right side of the engine compartment joining the vast majority of transverse FWD manufacturers. Perhaps there is an engineering reason for mounting clockwise rotating engines on the right and counter clockwise rotating engines on the left.

In both cases, when you rev the engine, it twists backwards, towards the rear of the car. I'm guessing that when the engine twists toward the rear, the car twists (or pitches) forward placing more of the weight on the front wheels thus improving traction during acceleration. Could this have something to do with the reasoning behind it? I realize this is not an M-100 site, but perhaps an engineer could shed some light on this.

[denicholls2]

I would think that the engine would want to be mounted so as to apply its torque to the side mount in tension rather than compression. Not sure if this is what actually happens.

Regardless, I believe the change is to accomodate the issue of the engine's rotational torque when revved. I'm sure the engineers know whether tension or compression is the better solution for the mounts used better than I, but I would expect the answer to be consistent for all engines of similar mount construction.