jay793 Posted December 1, 2007 Report Share Posted December 1, 2007 I put these cylinders on and saw that there's around 1/16th of an inch of the piston dome sticking above the exhoust port, and from my experience this looks wrong. I dont know anything about port timming so I was hopeing someone could fill me in and tell me what to do with this. Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted December 1, 2007 Report Share Posted December 1, 2007 That doesnt look right to be but I am not an expert. Maybe you have a set of cylinders ported for a 4mill stroker crank. Builders start by lowering the ports about 2 mm because the piston falls down in the cylinder 2 mm farther. Quote Link to comment Share on other sites More sharing options...
Coupelx Posted December 1, 2007 Report Share Posted December 1, 2007 agreed, it looks like it was ported for a 4mil. Quote Link to comment Share on other sites More sharing options...
jay793 Posted December 1, 2007 Author Report Share Posted December 1, 2007 if that is the case what do you think I could do, I measured the port and it looks like it is 3/16ths bigger than my stock ports Quote Link to comment Share on other sites More sharing options...
blowit Posted December 1, 2007 Report Share Posted December 1, 2007 if that is the case what do you think I could do, I measured the port and it looks like it is 3/16ths bigger than my stock ports If you want to measure the bottom and top of all ports relative to the deck, I can tell you if this is for a 4mil. You should be able to look down the barrel at BDC and see of the transfers align too. Brandon Quote Link to comment Share on other sites More sharing options...
jay793 Posted December 1, 2007 Author Report Share Posted December 1, 2007 when looking down the barrel it seems the piston is above the ports a hair, as for as numbers, it looks like from the top of the jug i got 1'' 11/16 to 2'' 3/16 on the sides Quote Link to comment Share on other sites More sharing options...
blowit Posted December 1, 2007 Report Share Posted December 1, 2007 when looking down the barrel it seems the piston is above the ports a hair, as for as numbers, it looks like from the top of the jug i got 1'' 11/16 to 2'' 3/16 on the sides Which ports are we talking about? what is a hair? accuracy is key here. I recommend a digital caliper at the minimum. If using a ruler, you should measure to the nearest 64th. Brandon Quote Link to comment Share on other sites More sharing options...
Aussie Quad Racer Posted December 1, 2007 Report Share Posted December 1, 2007 when the piston is at bottom dead centre, the piston top should be level with the bottom of the exhuast port Quote Link to comment Share on other sites More sharing options...
jay793 Posted December 1, 2007 Author Report Share Posted December 1, 2007 from what everyone is saying, it looks like there ported for a 4 mil. So what should i do sell them and start over, get a 4 mil, or try to work with what i got? thanks for all your replys Quote Link to comment Share on other sites More sharing options...
Bansh-eman Posted December 1, 2007 Report Share Posted December 1, 2007 rather then going off what everyone is saying, get a caliper and messure it to be 100% sure. would suck really bad to start buyig parts and end up not being what you thought it was. plus any mechanic needs a caliper Quote Link to comment Share on other sites More sharing options...
jay793 Posted December 1, 2007 Author Report Share Posted December 1, 2007 rather then going off what everyone is saying, get a caliper and messure it to be 100% sure. would suck really bad to start buyig parts and end up not being what you thought it was. plus any mechanic needs a caliper where can i get one and how much do they run, is one better then the other? Quote Link to comment Share on other sites More sharing options...
moneybags Posted December 1, 2007 Report Share Posted December 1, 2007 Most likely it was built like that by the builder. My pistions do the same thing on my 06. I have emailed a few builders about this. They have all given my veary detailed info about Y it's done like this. If I hadent trashed that PM I would have quoted it. On a side note my 421 cub motor is dead evan at BDC. Quote Link to comment Share on other sites More sharing options...
jay793 Posted December 1, 2007 Author Report Share Posted December 1, 2007 Most likely it was built like that by the builder. My pistions do the same thing on my 06. I have emailed a few builders about this. They have all given my veary detailed info about Y it's done like this. If I hadent trashed that PM I would have quoted it. On a side note my 421 cub motor is dead evan at BDC. so with this being like that will it run like shit? Quote Link to comment Share on other sites More sharing options...
moneybags Posted December 1, 2007 Report Share Posted December 1, 2007 so with this being like that will it run like shit? My 06 hauls the mail. Would be alot faster if I had a better pipes. I am pritty sure the person who built MY motor set it up right. Did you put that motor together. Quote Link to comment Share on other sites More sharing options...
flotek Posted December 1, 2007 Report Share Posted December 1, 2007 where did you get these cylinders from? this is why its a bad idea to buy ported jugs off ebay its like a box of choclates yo u just never know what your going to get Quote Link to comment Share on other sites More sharing options...
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