[Land-speed] Piston problem

[Skip Higginbotham]

Scott,
It would be nice to know what your fuel mixture and timing are. 9:1 
and 15lbs shouldn't be too much. If the mixture is 11:1 or just a 
little leaner, your problem is likely too much timing (or poor fuel).

Are  you burning the same pistons each time? Is it a hemi? What is 
your inlet temp??????

I run a BBC with 8.5:1 compression, 30 degrees advance and 20 lbs 
boost. (and really good gas 120 octane).....no burned pistons (yet). 
I am now adding an intercooler.

Skip




At 05:31 AM 1/23/2009, Scott Cowle wrote:
>Hello everyone. I usually write this site with questions that seem obvious to
>most of you I guess,my technical knowledge of engines is limited, but I have a
>curious situation with my big block mopar. It is a 500cid stroker motor with a
>procharger supercharger and I have consistently burnt up pistons I guess due
>to too much boost and too little fuel and too much timing. But this time I
>noticed that while I only hurt two pistons ,all of the pistons showed the same
>characteristics of carbon buildup. The half of the piston closest to the
>sparkplug has what I would call a normal amount of carbon on it but the half
>furthest from the plug has none.It does not matter how much fuel I give the
>motor the results are the same. This suggests to me that the flame is getting
>snuffed out as it goes across the piston .Is this what is probably happening?
>I know I have to reduce the boost from the supercharger-I'm getting 15lbs of
>boost on a 9:1 compression engine and this will be taken care of but I just
>wanted to know what was happening in the engine. I would appreciate any
>opinions on this . Scott
>
>
>
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