Hey ,
i read your post the other day..sorry for long delay...a few thoughts from my end.
i would leave the current heads alone..its a good bottom end head. i think the roller is a good thought beacuse of the pontential increase in ramp speed..which can help your bottom end as well..i just don't think your gonna see the best bang for the buck going with the Bigger port head your speaking of..you could very well lose some valuable TQ here going with a bigger head...i would think you need more of a torqy engine in your sport.
You can also angle mill the heads you got and get the compression up to 10:1 and still run pump gas.
what many people don't know is that if you did run higher octane Fuel (ex: 110) it would work against the lower compression engine
if they are not checking fuel (hydrometer) you can Mix some VP-C44 with your pump gas and it will wake up that bad boy up....you DO NOT want to know the price.
hope this helps some...its just My opinion anyhow..outside of the c-44..its fact ! 8)
ps: Welcome to the forum
Brian
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Bjuice..
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