TheSamba.com :: View topic - My 25hp <-> 36hp cylinder experiment

Thu Jan 31, 2008 6:13 pm

The good: I finally got my engine bits back from RIMCO
The bad: I broke my hand a couple weeks ago, so there's not much I can do with the newly-arrived parts

For comparison: the modified 25hp head vs a normal one, and a modified 36hp cylinder vs a normal one

Thu Jan 31, 2008 6:37 pm

Sorry for being ignorant, but what was the modification and what are you trying to accomplish :?

Thu Jan 31, 2008 7:10 pm

56OvalRHD wrote: Sorry for being ignorant, but what was the modification and what are you trying to accomplish :?

............and HOW exactly did you break you hand?????????? :D

Thu Jan 31, 2008 7:50 pm

The idea is to use 36hp P&C's to rebuild my 25hp engine. 25hp P&C's are on par with the GNP of Ecuador nowdays.

I broke a medial phalanges playing basketball.

Thu Jan 31, 2008 8:33 pm

I was hoping that was what you were up to.

Please keep us posted on how your tin fits over the 36HP barrels when assembled.

I'm hoping the top head tin screws down, then the shroud, then the lower tins. If it all fits OK, then we are all in business. It just sucks opening the case and heads because you can't go back. But, since the barrels and pistons are available new, you can't argue with reality.

Thanks for posting your progress. As you said, I just got my stuff back from RIMCO also, however I'm using 25HP cylinders that were oversized for bigger pistons. I was really tempted to do what you're doing.

Fri Feb 01, 2008 7:59 am

thom wrote: The idea is to use 36hp P&C's to rebuild my 25hp engine. 25hp P&C's are on par with the GNP of Ecuador nowdays.

I broke a medial phalanges playing basketball.

Yikes!! Your navicular (scaphoid) and greater multangular also appear to have suffered some compressive stress. Did you hit the floor hard, or get whacked on the back of the hand?

Fri Feb 01, 2008 8:35 am

thom wrote:

Did you cut your middle finger off at some point or.. perhaps you are a mutant? :) Can we get a full set to asses your physionimy... space creature. :D

Oh.. and OUCH! .. have a vicodin on me!

Fri Feb 01, 2008 10:13 am

Yeah, I cut off the tip of my middle finger and nicked the adjoining ring finger back when I was 18. My hands have had a rough life!

Fri Feb 01, 2008 12:41 pm

Rimco does nice work. So, you opened the 25hp heads up to fit a 36hp cylinder? Then milled the 36hp cylinder flange down to fit in the stock 25hp case?

Fri Feb 01, 2008 5:33 pm

I also had Rimco open up my case and heads for Porsche 912 88.3 which can 'just' be squeezed between the studs. I imagine the 36hp jugs should fit easily with no mods. The 912 cylinders required some mods but the tins fit once the fins were modified.

-Craig

Fri Feb 01, 2008 5:52 pm

a friend did the same , opened the 25hp heads and used 36hp liners .....he kept the manifold and carb stock (1953 bug)

he told me that the car runs faster now .....

Tue Apr 15, 2008 5:05 am

Was the mod worth it?

I was debating on doing this. Either boring our a set of 25hp cylinders to accept 36hp pistons OR opening the case/heads to accept the 36 P&C's.

I have a complete spare 1949 25 hp laying around.

Tue Apr 15, 2008 7:04 am

I'm still not done with the rebuild. The case is together, pistons and cylinders are on, but I'm waiting on a new set of head nuts - mine were iffy so I bought another set.

Last night I did a quick fit of the cylinder tin, and now I realize I will have to take #3 off and grind a couple of the fins off where they are too close to the case for the tin to slide down.

I didn't open up the case for the 36hp bits; I had the bases of the 36hp cylinders milled down to fit the 25hp case. My case was in perfect condition - it didn't need to be cut at all. On the heads, I had them cut 1/2 of the needed material off the cylinders and the other 1/2 off the head.

My plan "B" if this doesn't work out as planned is to go ahead and cut the case for the 36hp cylinders and cut the heads the rest of the way.