bansheewizard Posted August 29, 2004 Report Share Posted August 29, 2004 i got a compression checker today, and checked it. its at 180 psi, is that good or bad, thanks. Quote Link to comment Share on other sites More sharing options...
Indubitably Posted August 29, 2004 Report Share Posted August 29, 2004 It depends, whats your elevation? what head and size dome you running? Was this cold or was it warmed up? 180 psi seems like a lot to me, I've seen people running 160psi for methanol which typically needs more timing and compression. Quote Link to comment Share on other sites More sharing options...
a&sbanshee Posted August 29, 2004 Report Share Posted August 29, 2004 180 is alot if u ask me, i know in a drag bike espically on stock cylinders with that high of compression u will lose top end and trust u will notice the bike stop pulling under wide open throttle. the best way to check it is with the motor completely cold and put the gauge in one of the spark plug hole and while holding the throttle wide open kick the bike until the needle wont move anymore this will give u the best and most accurate reading in my opinion Quote Link to comment Share on other sites More sharing options...
bansheewizard Posted August 29, 2004 Author Report Share Posted August 29, 2004 it was completly cold and it came up 180 .i d k the elevation. i though it was pretty high is there neway to lower it it has the stock head its shaved, been ported ploshed, .60 over, 34mm carbs, v force reeds, spacers. i want to go faster on top end more then anything so help will be appriciated, thanks Quote Link to comment Share on other sites More sharing options...
a&sbanshee Posted August 29, 2004 Report Share Posted August 29, 2004 only thing u could do is get another head redone or add a thin base gasket or use a thicker head gasket on the bike and that should lower the compression some but i dunno exactly how much it will bring it down Quote Link to comment Share on other sites More sharing options...
Indubitably Posted August 29, 2004 Report Share Posted August 29, 2004 If you wanna go faster have a builder give you a little more exhaust duration and transfer that will lower your compression too. Quote Link to comment Share on other sites More sharing options...
bansheewizard Posted August 29, 2004 Author Report Share Posted August 29, 2004 If you wanna go faster have a builder give you a little more exhaust duration and transfer that will lower your compression too. exhaust duration whats this mean, sorry not much on this stuff Quote Link to comment Share on other sites More sharing options...
Indubitably Posted August 30, 2004 Report Share Posted August 30, 2004 o sorry, umm exhaust duration is how long the exhaust port is "open" in one cycle, when i say add more basically all I am saying ir to raise it a little more, which will lower your compression because the exhaust gets out faster. Same with the transfers too though just so you get the correct amount of flow. The only down side is that you will lose low end, but gain top end so choose which you want. Quote Link to comment Share on other sites More sharing options...
97redshee Posted August 30, 2004 Report Share Posted August 30, 2004 i got a 4mm and i have 190 psi.built it this way cause it gives the buike a lil better botom end.im a fat ass so i neded more power down low to get me movin. Quote Link to comment Share on other sites More sharing options...
sredish Posted August 30, 2004 Report Share Posted August 30, 2004 180 is not a problem as long as your using the proper gas. If you want to take it down, then buy a head from someone on here or buy a head from dlnoss aka Noss Machine.com. Quote Link to comment Share on other sites More sharing options...
bansheewizard Posted August 30, 2004 Author Report Share Posted August 30, 2004 what would be the proper gas im running 97 thanks Quote Link to comment Share on other sites More sharing options...
sredish Posted August 30, 2004 Report Share Posted August 30, 2004 what would be the proper gas im running 97 thanks No no no no no!!!!!!! 155lbs and under, 93 and under. around 160, 97, maybe half race, half pump. 180, your gonna want some 110 or higher race fuel or else your gonna detonate and do something very bad. Quote Link to comment Share on other sites More sharing options...
97redshee Posted August 30, 2004 Report Share Posted August 30, 2004 i run 190 psi and run vp c-12. Quote Link to comment Share on other sites More sharing options...
frocashmoney24 Posted August 30, 2004 Report Share Posted August 30, 2004 def what sredish said, thats the rule of thumb as far as gas and compression, how long you been runnin thee bike like this? Quote Link to comment Share on other sites More sharing options...
bansheewizard Posted August 30, 2004 Author Report Share Posted August 30, 2004 ive been on it with this gas for bout a week . so i need to run straight cam2. and is 32:1 sound good , sorry bout all the questions. just want to get it rite if you know what i mean thanks Quote Link to comment Share on other sites More sharing options...
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