Here are some pictures of the modifcations done to the heads on Scott's car that are supposed to deter detonation greatly. Once he gets it all going again we can see if this mod works well or not. Hopefully it does since that would be an easy to way to help the motor keep from detonating even more.



Also, here's some port work he did to the heads while they were off:

 

those little cuts in the head help deter detonation? I've never seen that before. Those pistons have a lot of build up on them.

 

yeah, they are supposed to swirl the mixture around a bit more.

 

opening up the exhuast side should help detour detonation too, keeping th exhuast gas outta the combustion chamber. Bigger valves and a different cam could help too. I have never seen that before. I am going to use your picture and ask some people.

 

i talked with scott earlier today and he said that they are back on his car.

this is interesting.

 

I read that article in Popular Science this past summer and tried a experiment on the kid's PW50. (two stroke motorcycle) did the same basic cuts discribed in the article and pictured above. It made some noticible power and kept the plug clean.
The idea is that as the piston pushes the air/fuel mixture up towards the head the V grooves chanel the mixture being pushed on them into the center of the chamber and keep the mixture swirling/mixing instead of being stagnant out there sandwitched between a flat head surface and flat piston surface.
The pistons build up is very light and only around the outside it came right of with two passes of steel wool.
The article who was writen by a guy from Inda races but the only fuel they have there is 70 somthin octane! He would raise the compression in his engines but kept being limited because of detonation. These V grooves took away detonation with the same fuel so he could keep raising compression. It also improved gas milage and better emmisions.
Most of my car is a experment anyway so I thought since I know what gas milage I've been getting and documented just about everything with the car why not try it out?
The grooves extend about a 1/8 before the edge of the head gasket.
I should have everything back together this week/weekend..
I'll let you know the results.. good or bad.
~Scott

 

cant wait to see the results of the experiment

 

looks good. Hope it goes well. Let us no.