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Old 01-28-2015, 06:55 PM
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mapbike mapbike is offline
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Join Date: Mar 2010
Location: Central Texas
Posts: 5,379
Default Re: Curious about the engine, :question:

Originally Posted by Greg58 View Post
I was confused about which piston works with which crank and with which cylinder does best for port timing etc.... Long before I read this thread intirely. Now I'll have to follow just to see what y'all figure out!
I do know that the ZAE50 stamped rod engine has to go with a pk80 type jug and piston thats typically used on a 40mm stroke engine, I have two of these engines and both need that set up, the main issue with the HB engines is that the pk80 type jug is a 1/16"/ .062" to tall and at BDC the piston doesn't fully open the exhaust port, also think the HB type engine just like the GT5 can benefit from some slight piston ramping at the transfers as well as maybe just a little on the exhaust side of piston, I think possibly that these engines will perform better in the higher rpmsif two base gaskets are used and for sure the deck height needs to be brought down a good bit, maybe as much as .070 ot so if two base gaskets are used.

im gonna experiment a little with mine just to see what if any gains will be realized when I raise the ports, shave the deck and add some ramping to piston but ramping will be just a small amount so hopefully I dont kill the bottom end grunt to much.
I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!
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