It's nice to have a hand full of pipe seals, o-rings, etc. I'm not sure how much heat the .15 generates but if it follows the same "rules" as other piped engines I've run.......if you are melting pipe seals often then you have a 5 or 6 item checklist to investigate.
A blown pipe seal during a speed run is like adding air to a cutting torch. I
believe it is possible to have world class performance with out smoking hot runs if you find the perfect balance of all the things that you have control of as tuning tools. The prop itself and compression being the most critical tuning tools. Once you arrive at the perfect prop, then you want to crank out several copies from the rough blanks while magic knowledge you gained is fresh in your head ..!!!
Hopefully too...there is an "off the shelf" prop blank that doesn't require much sculpture and it becomes one you can get cheaper by the dozen or else make your own.
The YuckDamn 2.5 has always been on my list for the challenge. I remember Patrick having trouble dismantling his because the slot head screws that held his together were so chinsy that they were not budging loose without ruining the slots . He got it for something like $20 with a pipe included..!
I don't know if AJC or Andy Woitkowicz ever played with one of these, but I would try to do it Andy Style and use replacement parts from similar engines that are dimensionally close to what is needed.
Last edited by combatpigg; 04-04-2014 at 10:40 AM.