I just finished building the Polini stroker for the zx. This one is the Corsa race jug at 47mm 72cc. I haven't done the math yet but with 4mm more stroke you all can fiqure the new cc's. Polini uses an aluminum base gasket so I replaced it with some soft 2.8mm stock to get a dead even deck, and a .5mm squish. This head has a 5.5mm squish band as well as a controlled combustion chamber design. Pretty cool looking head in my opinion. I know everyone will want to know the timings on the jug but I have no idea yet. I am using a Tech next pipe because of the low power band for now. I only want to break in the jug before I throw the good stuff at it.
I used my Ruima 44mm stuffed crank w/ new bearings, and some drastic case flow porting. This WAS an OEM case before today. I opened the intake completely (no bridge) and drilled the crank oilers/removed all the bracing at the top of the crank charge loop, and polished the top 1/2 of the case. The bottom is scotch brite finished to hold the oil down there. Boost port was cut, and the piston was skirted 3mm on each side to reduce spinning weight, as well as reduce drag.
I am using the CT intake with Boysen (0.030") reeds. I did something special here too. I drilled 4 1/4" holes in each of the four petals and covered the holes with 0.08" reed stock to make my version of 2 stage reeds. These are set into a CT stuffer. The carb is the 24mm OKO with as of right now unknown jetting. (I just forgot what's in it).
4 heat cycles, 2, 5 minute runs, and I rode it the 6 miles home from the shop. I NEVER went past 1/8th throttle. This case now has the unknown 8.3:1 secondary gears from my other case, and the Malossi primaries. It final drives at 7.1:1. The Malossi's are not as low as I wanted so I have some polini's ordered to get me to 6:1 final.
At 5,200 rpm 1/8th throttle I am cruising 45mph. The mph is from the clock, and the rpm is from a DMM with an inductive wire pick up. It is Slightly lean but ridable at low rpm. I have 2 boxes of jets to use after I cut/solder to find which jets to use for now.
The Scorpion pipe is in customs in Honolulu, and the MSD cdi is almost ready to ship. HGT is setting up a Malossi Rep. bike using the MSD to dial it in, and when he finishes this week it will be in the post. I will set up my OWN timing curves to elimenate the sustained hi heat from long wot runs. The New curves, and some crafty needle tapers WILL result in the forums first DOCUMENTED 80-90mph ZX. I have one of those Krazor phones so I can do a vid to back up this claim. This Won't be a wheelie popper but it will be a top end cruiser. Looking for 60 all day, 70 to pass, and 90 on the true 1/4mile. Since the gearing gets me 45 at 5200 I think this is doable. Haven't even come NEAR the pipes 7g's. If the Scorpion wont get it at 8500 the Windjammer will at 9500 with some minor port raising.
Wish me luck Bros! The next week end will tell. (or whenever I get the MSD) I'm NOT beating this build without it... I also have a 60,000 volt Granatelli coil from a Mustang application because of it's small size to fire gap less plugs.
http://www.mpsracing.com/instructions/MSD/4217.pdfhttp://www.jegs.com/i/NGK-Spark-Plugs/739/R847-10/10002/-1?parentProductId=753645#moreDetailshttp://www.jetav8r.com/Vision/Ignition/CDI.htmlhttp://www.stage3motorsports.com/c=KRdEXp9LkI3AXOdpG1W2aOBwV/product/GMS-28-1697CP/1999-2004-Mustang-GT-GMS-2V-Pro-Series-Coil-Packs-Set-of-8.html The price is 1/8th the total shown as I only need one. These fire a 12 heat range gap less plug, and are Supposed to keep it under control.... We'll see.
