Has anyone else bothered to do this? Is it really worth the effort? The housing is this picture was not even complete yet, and had already consumed a few hours of my time. Still hoping some of the big boys will chime in with some big secrets!

 

It was done to mine. I can't tell if it helped but, it sure doesn't seem to have hurt.

May I use your photo on my web site to illustrate what the mod looks like?

Mike

 

Hey Exit,

How does ribbing the water jacket help? Does it create more surface area or something like that? Later --Tommy

 

Yes, it increases surface are to assist heat transfer out of the housing. It is usually only done on the combustion side, to eliminate hot-spots that lead to detonation. I put extra effort into the spark plug area. I still feel that I will never know if it actually helps. When the engine fails, nothing helps -- but I make every effort to avoid it!

Mike: feel free to use the picture, just give me a link or credits. I have the full size image if you want, and some others. Email me, and I'll attach them.

 

How'd you do that? With a Dremel and a small cutoff wheel or something?

 

After trying every dremel attachment known to all of mankind, I finally stumbled onto the perfect bit. It looks like a 1cm saw blade on the end of a shaft. One blade lasts about long enough for one housing, and you have to clean the aluminum from the teeth frequently. Using a medium speed versus a high speed helps avoid clogging also. I use this for all of the the broad, flat areas. Next I use a small tungsten carbide ball-tipped cutter (1/8" perhaps?) to get into the corners, and to do some fancy work around the spark plugs. It takes about 2 hours per housing. Fun. Wal-Mart (believe it or not) has an excellent selection of tips, followed by Lowes. Strangely, both stores do not carry the same stock -- so visit both for the most options!


Here is a simple representation of how surface area is increased:

Section of original housing surface , unit of 2L:

_ _
.....

Modified housing surface, width of 2L, depth of 1L
_
..|_|

Thus, if your cuts are L deep, and spaced L apart, you will exactly double the surface in the treated area. Deeper cuts could result in more area, but would be more time consuming.

Maybe an M.E. could study this for a senior design project to see if the actual flux out of the housing is increased under actual operating conditions? (Hint, hint!)