ORIGINAL: tigrejohn
Is Kustom Kraftsmanship, or its successor, still in business? They supplied many mod parts for TD and BW. One item I remember were cylinder shims so you could adjust port timing of the cylinder. But I can't remember what the instructions were. I noticed that Gibeault made no mention of this procedure. Maybe that was the secret to his success. What would be the best setup now on a BW for Mouse?
Solutions: Modify the needle valve assembly as follows,
as the stock needle leaks air. Remove needle valve, discard the spring, install a #4 flat washer, and then add a piece of ¼” silicone fuel tubing. Re-install the needle valve and you now have one cheap, but airtight needle valve assembly. With the tank and tank back together, remove the screen and drill out the tank and tank back inlet venturi to .082”, (this is what the record holding engine used). This produces a gain of about 500 rpm, but at the expense of less fuel economy. Use one of the larger 8cc tanks for the greatest range. These are commonly found on Golden Bee, Super Bee, & Black Widow engines. The Venom uses this as well, but the venturi hole is already at .082” ID. Next sand the tank back flat over glass (again with the 400 paper), as many tank backs are warped and do not sit flat when bolted to the firewall. While you’re at it, use your dremel tool to grind away the screen holder from the venturi area of the tank back. Do a good job of blending in this area. The fuel pickup must be located at the outboard corner, and then held in place. Using a pin drill, drill a tiny hole through the “fence” where the tank back joins the tank, and wire the neoprene tube in place with some .020” stainless steel wire, (S/S is non- corroding). If you have a tank back with no “fence” you can also get the neoprene pickup tube to stay in place by inserting a small piece of 1/16 brass or alum tubing, about ¼” long. The net effect will be that the tank front will now hold the pickup in place. Or, bend a piece of soft aluminum tubing & make the pick-up one solid piece. Attach it to the tank back with a short piece of silicone tubing. This works well on the BW. I have tried various positioning of the transfer ports and I found it made no difference in the RPM. The shims do make a difference in exhaust duration though.