coolant passage mod.
 

there is a mod where they increase the surface of the coolant passage by grinding it and making it like a heatsink.
anyone know how to do that ??
and what is that called??

I've just ground some grooves in the coolant passages to give more surface area. Around the spark plugs gets extra attention.

It is called the rotor housing water jacket modification.

Just around the spark plugs, or all coolant passages?

Can this mod be overdone?

Any cons to this mod?

Racing Beat just does it around the spark plug area. If it's overdone, it weakens the structure. How much is too much? I don't know. I considered it for my recent 4 port 13B, but decided against it since I've never seen it in real life and won't be racing the engine.

Anyone have pictures? Or know wheres theres a writeup?

http://www.rotorsportsracing.com/per...htm#coolingmod PICTURE

if i wanted to do this kind of mod, what kind of tool should i use??

Die grinder with a burr that gives you any kind of "V" profile or the top corner of a cylinder shaped one.

Would there be a point to doing it anywhere aside from near the spark plugs? Perhaps near the intake and top of the rotor housing to cool it through the intake phase? Or would that actually heat up the incoming fuel/air mixture?

What about near the bottom and exhaust ports? I suppose no gains there, as you want all the expansion you can get there. and once the burned mixture is gone, there's no need or way to cool it.

If you have access to a Knee mill, CNC mill, or any other type of metal milling machine, you could probably use a rough edge end mill.

Other than the plug area and maybe the exhaust area you would be better off slowing down your water pump to slow down the water a little. I made a bigger water pump pully after I installed a smaller crank pully.(No room with a stock crank pully) this helped a lot of things on the racecar.