2004LEBanshee Posted April 24, 2007 Report Posted April 24, 2007 I currently have a dune/play port from jeff. +4 crank extra weld, Noss head with 20+2 domes. Also +5 timing. I wanted to and was running mix race and pump. The engine has about a gallon and a half through it and I did a compression check and it is on a cold engine 184 on both cylinders. I assumed with a port job it wouldnt be this high. But I guess its Ok. I dont mind running straight race but Im guessing I may need to. I also think it may be a little higher once it is warmed and broken in is that correct? Quote
David Keith Posted April 25, 2007 Report Posted April 25, 2007 I currently have a dune/play port from jeff. +4 crank extra weld, Noss head with 20+2 domes. Also +5 timing. I wanted to and was running mix race and pump. The engine has about a gallon and a half through it and I did a compression check and it is on a cold engine 184 on both cylinders. I assumed with a port job it wouldnt be this high. But I guess its Ok. I dont mind running straight race but Im guessing I may need to. I also think it may be a little higher once it is warmed and broken in is that correct? That's 12.5 to 1 compression ratio! Is your gauge accurate? If so, keep using your higher octane fuel. Quote
Snopczynski Posted April 25, 2007 Report Posted April 25, 2007 Your gonna have to let me know what a 20+2 dome is. Quote
wesw Posted April 25, 2007 Report Posted April 25, 2007 (edited) 20cc dome thats cut 2mm to allow for 4mm crank yeah 185 psi you better run 110 easy. wow i ran 20cc on my old 4mm got like 175. at 1000ft better be safe than sorry imo. also you might check your squish with some solder. to double check everything out. Edited April 25, 2007 by wesw Quote
locogato11283 Posted April 25, 2007 Report Posted April 25, 2007 have you talked to jeff about it?? i know that the 4mm motor he built for my bro a couple years ago had 180 pounds. it had all kinds of power down low.. Quote
2004LEBanshee Posted April 25, 2007 Author Report Posted April 25, 2007 Yea I sent him a message today no answer. 20+2 is 20 cc domes for the added stroke. I thought this was high but plugs look good no detonation yet and no signs of hitting the piston yet. Quote
Leadfoot350 Posted April 25, 2007 Report Posted April 25, 2007 take them off and have him cut them more. Unless if you dont mind running 110 Quote
FASTOYS Posted April 25, 2007 Report Posted April 25, 2007 2004lebanshee, you will need to run 110 race with that setup! If that wont work call me as i didnt get your other message... That thing should pull the azz out of a rhino and be a damn fun play bike. Quote
dajogejr Posted April 25, 2007 Report Posted April 25, 2007 You and that damn Rino...Jeff...LOL. Yeah, 110 all the way...you could probably throw a tad more timing into it to and play around. Unless you have an all out drag port, your cranking compression won't go that much lower... Did you check squish when you put it back together? (or did Jeff assemble it for you?) That's gotta be a fun ride. Quote
2004LEBanshee Posted April 25, 2007 Author Report Posted April 25, 2007 Na I dont mind the 110 for now Ill give it a shot what timing should I advanced to Im at 5 now. Also I assembled it. No I didnt chech squish. Quote
dajogejr Posted April 25, 2007 Report Posted April 25, 2007 Throw 8 degrees at it...see how it likes it. Keep an eye on your plugs. Quote
2004LEBanshee Posted April 25, 2007 Author Report Posted April 25, 2007 well I guess I did kinda check the squish. I used a screwd driver and put in the hole and put the pistion to top dead center and measured it. It was longer then the length of a spark plug screwed in. so sorta. I was a little worried when I saw the piston come out of the cylinder a bit before installing the head. But I guess its supposed to . Quote
dajogejr Posted April 25, 2007 Report Posted April 25, 2007 Squish is checking the dome of the piston to the surface of the head dome... Solder is used to "squish", then measured with a micrometer... Yeah, the piston will travel above 0 deck height on a stock cylinder with a 4 mil stroker, thus the need for a "+2" cut dome.... Quote
greg_banshee Posted April 25, 2007 Report Posted April 25, 2007 will the pistons travel past 0 deck height even with 795 series pistons ? will i have to have my domes cut ? Quote
FASTOYS Posted April 25, 2007 Report Posted April 25, 2007 That motor will run great at 5 degrees. I dont think you will need anymore timing unless you are on/off the throttle like MX or Drag racing. If you are running long trails, roads, open dunes, goofing, etc. then your fine where your at. 7 degrees will make alittle more power though IF you think you need it. Call me/pm me and let me know what your squish is. Should be around .035 -.045 range. :beer: Dave i can relate to a Rhino azz cause i have one. :yelrotflmao: jk Quote
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