thunderhead289
New Member
for the benefit of all I hope that anyone who has had a blown engine will share all details such as
engine oil used
at what ratio
size engine
any modifications to engine (compression increase, porting, carburetor, exhaust pipe)
-25:1 oil ratio
-66cc (generic but not bgf)
-boosted compression by shaving my original head
-carburetor set to one notch richer on slide pin
1 hole drilled through my old-style exhaust pipe baffle tube for a very slight increase in flow due to the compression increase.
-boost bottle
-wallmart brand 2 stroke oil (yeah I know shame on me)
rings were pretty worn down. minimal carbon for such mileage. ran it good and rich, just ran it pretty hard in the rpm's. lasted many miles for what I put it through. rings failed due to the fact that they are simple iron rings. I do SBF & SBC builds and always use moly coated rings(what all cars run today). those iron rings only last 80 thousand on a car tops and they aren't running between 3500 to 5500 rpm none stop.
wristpin wear was very very little despite the deformed wristpin. could not feel any up and down play in the connecting rod.
ran darn good right up until its final wheelie. was actually still running on that junk, I just shut it down because I knew it was had and did not want shavings going into crankcase.
bottom end is still very solid. 35 dollars in parts waiting at home to completely redo the top end. will make a vid on that when I do it so all can see how that's done.
there I do believe I have explained myself.