OK I have given up on finding a couple of needle valves for the 2 McCoy .35 red heads that I have. What spray bar Assembly would be a good replacement ?
Thanks,
Tom
Tom, being an active CLer back in the days when the McCoy was an everyday engine, let me say a few things.
1. Ref. needle valves, the OS regular NV is tops. Enya is a very close 2nd choice. In a regular venturi use some small washers as needed to place the NV metering hole directly BACK towards the cylinder of the engine. Rotate it to just be out of sight. That is the lowest pressure differential in the venturi and will serve you well.
I use to use the same set up in Foxes, Johnson Stunt Supreme (which needed a restricted venturi) and a G.Aldrich built ST. 40. Actually my well broken-in Fox Stunt 40 was every bit as good as the ST 40. I only used Fox Superfuel in those days.
2. If your McCoy 35 is the traditional testor's built Red-Head stunt-type engine (NOT a Duromatic rear rotary or silver colored sport engine) it will require a very oily fuel to last any significant time, or be "swelled".
Back in the '60s when there was a lot of iron pistons, especially in the speed circles, a favorite item was to "Swell" the pistons with very high RPM , props cut down to short diameter, and let 'em heat up big time. Better have a fair supply of pistons when doing this. Now there were some very successful "swellings" of the McCoy 29-40 engines. It can be done.
3. If your McCoy 35 is one of the Series 21 engines, gray and ugly, then that engine has a dykes ring and not subject to "swelling". Those engines performed fairly well in the RC mode. However in the CL mode, they may well have done OK for the sport flier, but since the piston, ring, and sleeve porting was simply all K&B Series 64, then it was NOT set up for Stunt, regardless of the claims made by Testors. So proceed at your desire.
In 1971, I was at my peak of CL Stunt in the Chicago area. At the last moment, I agreed to fly a preproduction Series 21-.40 at the NATS. I had 4 runs prior to my first official. OK but not really a confidence builder!
Well on that flight I knew I had a real flight going using an original design model (That was the last year of Navy judging) until as I came out of the 4-leaf clover that #&%XXX*^# went into rat race lean and I landed after some 12 minutes. No pattern points and no landing points. Either would have placed me in the finals. Of course I set rich for the 2nd flight and wobbled through the pattern like I had never flown a stunt pattern.
The OS NV cannot correct ALL problems.
Topic: Spray bar and needle valve for a McCoy .35 (Read 7958 times)
