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C-10 head porting

S

snopro00934

Guest
Guest
Can anyone tell me if some mild port work is worth the time spent? I've got the head off and may install valve seals, by then it's just grinding time. SISF any thoughts? If she is too choked up, then any port work would be for nothing. Thanks-Eric in VT
 
Thanks Steve I will probably just clean everything, and get the ex ports closer to the header diameter. Saves me a ton of time.
 
Steve in sunny Fla said:


I never liked the engine as much with the new head. Tough to tune, not as sharp to throttle. Fuel economy lacking.

Steve
Click to expand...
In the early 70's, Sonny Leonard's original shop was just up the street from our bike shop. Did a bunch of welding on his engine parts, and your JB Weld heads reminded me of a set of his aluminum heads that I welded up the intake ports on for the same reason you did - to increase the air velocity into the engine. Back then we called it de-porting.
 
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I worked at an indoor Kart track. They had a few sets of karts and one set we called the 9 hp karts. They had the biggest engine and no governors. You had to pass a test to get the license to drive them. These karts were no joke. They were called sodi karts. They cost $6000. They had Honda gz270 engine. I started modifying them. I advanced timing, played with sprocket sizes, jet sizes, stiffer valve springs. Eventually I got a bunch of the heads milled. I tried my hand at porting them. I opened the intake port up. The fastest kart was the one that I killed but didn’t port. The ported ones had a slight high rpm advantage but it was more beneficial to have the torque coming out of the corners. If I were going to do anything to the Connie head it would be just to smooth the casting and remove any imperfections and not try to open anything up. Raise the compression if you could manage to compensate the timing difference.
 
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