520HC conversion of C195 rearend

[Skipper 1,788]

Hi guys

 

I need your big minds to figure this out. I know it is doable, just not what parts I need.

 

I want my C195's to run faster for commute between jobs, and the solution is among other things, an HC conversion. Since I am in Europe, it would be a lot easier to ship only the needed parts, and not whole doner units.

 

So, a shopping list for all things needed to convert the C195 hydro unit / rear end into HC spec, is what I need. Hope someone will spill the beans on this one, 

 

Oh and if someone knows how much faster it will get, that would be great too

 

And if any of the people that has done this before could enlighten me on the pros and cons, that would be great too.

 

Thanks

Edited March 8, 2018 by Skipper

[WHX?? 49,177]

Just thinkin out loud here but any chance a re-pulley might give that extra speed?

[Skipper 1,788]

Good suggestion, but no, would be my initial take on it. The engine and trans pulley are the same size, and the hydro is only rated for 3600 rpm. Therefor it needs to be done primarily in the transmission . To be fair, I had that thought also, but came to the conclusion that even if I push the hydro to 4000 rpm, that would still be an insignificant gain, especially considering the potential risk of long term damage to the unit. I'm aware there is of cause a safety margin from rated rpm to what it can handle in reality, but pushing the limits is not what I'm going for in that aspect. I need it to be reliable as always. If consensus are though, that it is OK to push it a certain amount of rpm, that is something that can also be done, as it is most likely a series of thing needed to achieve the desired speed.

 

To specify. I'm not looking for a total of 5-10% gain, but more in the 50-100% gain. I'll take what I can get, but the aim is high.  

 

Things also in progress is 31" rear wheels, and of cause bigger fronts too, not that the fronts matters for the speed of it.

 

Thanks for the input.

 

Anyone with experience in over revving the hydro please chime inn.

[WHX?? 49,177]

50 minutes ago, Skipper said:

but more in the 50-100% gain.

Well the bad news is you won't even come close to that kind of gain with an HC hydro ....

 

Not sure what a 195 hydro runs at for ground speed but probably not much more than 5 or 6 MPH?

Edited March 9, 2018 by WHX14

[Skipper 1,788]

Actually is does more i think, it also feels that way. I have several 8 speed and hydros of C and 300 and 400 series, and all are considerably slower than the C195. This is the math as far as I can tell from available data. The wheels turn the same revs as the 520 trans (or any other comparable hydro trans) as far as I can figure out, but it runs on 27" standard. Which in effect should make the C195 std. run 7.5 just like the HC on 23"

 

So if we go with the HC trans figures of 7.5 on 23", that makes for a 17.5% increase over the H trans. Then we go with the 27 tires, which also ads 17,4%, it should be achieving a total of 8.8 mph. Just standard C195 with the HC conversion. Now, if we go from 23" to 31" tires, there will be an extra 34.8% over the 7.5 mph. that makes for 10.11 mph, and that is in total an increase of roughly 35%, for a C195 with HC conversion and 31" tires. Now could we safely increase the rpms of the hydro, we might get close to the 50%, but let's see what the jury says on that first. 

 

Could we push it to 4000 rpm, that would make for an accumulated total of 50% increase, or 11.23 mph (18.1 km/h). That would make a heck of a difference between jobs, or a lover rpm commute. Heck, even the 10.11 mph is a really good speed.

 

Please anyone with experience, chime in please.

 

Edited March 9, 2018 by Skipper