I installed my 13:1 piston and have it completely back together but I need to know which timing mark to go off of on the flywheel. There are like 5 marks and None have a T for top dead center. Anyone know anything

 

I got the timing figured out and finished my 13:1 project. It is definantly snappier and a little torquier through the rpm range. Was it worth the money, for me it was because I put it in. If you were to take it to a dealer and pay I am not sure.

 

A little more pop and straight race gas. I can still run pump fuel on my 13:1, there is no way you will be able to do that with a 14:5

 

Why run pure race gas on an engine that does not need it. I could see maybe a 30-70 mix or 50-50 mix but straight is a waste of money. 110 octane is to high for 13:1 in the yfz. All you'll do is lose power by overkilling it. High octane is for preignition, if you don't have preignition why waste your money.

 

iluv2try,

mate well said, I find it bemusing that so many people believe higher octane must be higher hp, but it is the same mentallity that makes people take vitamin supplements, if you allready have your quota all they do is give you expensive urine.

Geoff.

 

My point exactly!