how many hours are we getting out there before pulling heads for carbon cleanup or hand lapping valves? i have 170hrs on 3litre and heads been off twice for clean up and valve work. 

i am using decalin and marvel as fuel treatments with re-jetted ma3 carb fixed my fuel leaks and intake is tight any ideas on reducing carbon buildup?

anyone running a 3250? and how is it going? Are you satisfied with the engine builder if not yourself?.

i have spoken with Wesman's about this and my air fuel and timing setup is reasonable but he did recommend installing turbo valves from Clarks $185 for full set, which i did.

i am looking for ideas to reduce carbon buildup and valve wear to minimize removing heads to at least 500hrs. Everything i know about decalin and marvel they should reduce carbon buildup.  

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I have learned a few additional things to minimize valve issues:  

Use clarks turbo valves

Compressed spring tension 100 to 110 pounds

Valve seats to approx .060, keep them narrow

Use Additive decalin in fuel

Run a step colder spark plug

I am not going to use marvel in the fuel as i have been 4oz / 10gal, everything i know about marvel it should reduce carbon buildup but going to give it a try anyway.

The first thing you should do is pull on that mixture knob a little bit.


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