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Greg,
Please let me say I'm not a naysayer and re-reading my last post it might have sounded rather aggressive. Please understand that isn't what was intended. My intent was to mention that I have never seen really MEASUREABLE results with any kind of wrap. In an aircraft application my worry would be exactly as stated before, you couldn't see a minor crack until it was already dangerous. Since a turbo application uses the exhaust manifold as a minor structural member I'd suggest coating rather than wrap. It looks a great deal better too.
Bill Jepson
-----Original Message-----
From: Greg Ward <gregw@onestopdesign.biz>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Tue, 4 Mar 2008 11:21 pm
Subject: [FlyRotary] Re: Exhaust? was [FlyRotary] engine installation pictures
No answers to any of these questions Bill. I will call Brian tomorrow and see what's up, and get some specifics. He brought it up because we have been talking about the turbocharging issue, and how/where to locate all of the parts, including shielding.
Greg
----- Original Message -----
Sent: Tuesday, March 04, 2008 10:57 PM
Subject: [FlyRotary] Re: Exhaust? was [FlyRotary] engine installation pictures
Yeah, and my friend in SoCal, the Racer again, says that the 20B racers down there wrap, and it really helps. But then again, racers......
Greg
Greg,
And they tested this how? With what instrumentation? So you know I have built racing cars and bikes for others and I have road raced motorcycles myself. The only coating or wrap I could find that worked was the Jet-Hot coating. That was on a motorcycle. The in cowl temps were reduced by 15°F. There wasn't any HP increase that I could determine reliably. I did record an increase on the wheel dyno but not enough to be certain it wasn't just different temp and baro pressure conditions. The rotary exhaust temperature is so much hotter that Jet-Hot has only had a suitable coating for about a year and a half. I'd try that if you must. Shielding, even thin and close has proven to be effective, as has zirconia ceramic blanket. The wrap may not have actually caused the cracking on the exhaust system mentioned previously but it certainly makes it impossible to detect cracks before they get dangerous. I'd stay away from wraps for just that reason.
Bill Jepson
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