[NSRCA-discussion] For Sale

Fri Feb 10 20:51:31 AKST 2012

Funny, I remember all the numbers still.  I ran the Webra 61 rear exhaust short stroke (160 degrees exhaust duration) on 5% fuel, Rossi R-8 or OPS RC-300 plug, IM pipe at 14-1/2" from the high point to the plug, Max Dailey 11-7.5 prop at 15,200 rpm, not many (if any) engines could do that.  In contrast the OS 61VF rear exhaust has an exhaust duration around 148 degrees and was a full 800-1000 rpm less with the same setup (except the pipe was between 12-3/4" and 13-1/4" from the plug to the high point).  The Short Strokes were all about 12-18 degrees less in exhaust port duration which made them less peaky with a bit more torque.  The overall HP was actually less, but more usable for the new style of flying, and the lowered RPM also helped with propeller efficiency. Interestingly, the Webra 160's I flew for several years before going E had exhaust durations of only 128 degrees, closer to a control-line stunt motor.  At that point the tuned pipe is essentially a big muffler, and the motor would actually slow down at the bottom of a Split S!

Fun times!

Jerry

Sent from my iPhone

On Feb 10, 2012, at 9:20 PM, "Verne Koester" <verne at twmi.rr.com> wrote:

> Hi Jerry,
>  
> I don’t recall but it would make sense that it would. They just seemed to breathe and work with the pipe a lot better and the power boost was impressive. It’s amazing how much I’ve forgotten about back then but the pipe was a Hatori and I think we ran the header full length with about a ¾” gap in the coupler. I want to say that the prop with that combo was an APC 13-10 but I wouldn’t swear to it. By comparison, I found the Hanno to be unimpressive but that anodized head looked pretty nice. I’m pretty sure I was running K&B 1-L plugs and low nitro fuel, like 5 or 10%. If my time frame memory is correct, they were in Summit II’s and Summit III’s.
>  
> I actually swapped out the Hanno for one of those modified long strokes because I wanted the extra power. I also tried a YS long stroke back then and it didn’t make as much power either so I sold it as well.
>  
> The tip about raising the port actually came from Dave Scully (Aero Composites) and I’m pretty sure he learned it from either Geoff Combs or Dean Koger. I remember it being a very easy and powerful setup that didn’t require frequent needle tweaking. I seem to recall having some header breakage problems early on that we resolved but I can’t remember how. Maybe making the pipe mount softer so it could move with the soft-mounted engine? Anyway, I was fortunate to have a friend at the time that had daily access to a Bridgeport so the mod to the exhaust port was no problem. Seems like a lifetime ago….
>  
> Verne
>  
> From: nsrca-discussion-bounces at lists.nsrca.org [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Budd Engineering
> Sent: Friday, February 10, 2012 11:31 PM
> To: General pattern discussion
> Subject: Re: [NSRCA-discussion] For Sale
>  
> Hey Verne,
>  
> By doing so you extended the relatively conservative exhaust port timing, upping it into the range of the Webra's, Rossi's, and OPS's.  The OS were always under scavenged compared to other motors of the day, and accordingly lower in power output.  Just guessing, but your fuel consumption went up a bit with the mod?
>  
> Jerry
> 
> Sent from my iPhone
> 
> On Feb 10, 2012, at 3:47 PM, "Verne Koester" <verne at twmi.rr.com> wrote:
> 
> Back in the day, I had both Hanno’s and the standard .61 long stroke. On a tip, I had .030 milled off the top of the exhaust port of the standard non-Hanno version. I ended up selling the Hanno because it couldn’t match the power of the modified .61 long stroke. In time, I had three like that and they were all awesome. BTW, I had the ABC version.
>  
> Verne Koester
>  
> From: nsrca-discussion-bounces at lists.nsrca.org [mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Keith Hoard
> Sent: Friday, February 10, 2012 6:02 PM
> To: General pattern discussion
> Subject: Re: [NSRCA-discussion] For Sale
>  
> ROFLMAO!!!!
>  
> 
> Keith Hoard
> Collierville, TN
> khoard at gmail.com
> 
>  
> . I doubt that any are a Hanno....I'd already have it in my grimy hands....but you never know!
> This listing is just round one!
>  
> Rex
>  
> Date: Fri, 10 Feb 2012 16:40:09 -0600
> From: scmcharg at gmail.com
> To: nsrca-discussion at lists.nsrca.org
> Subject: Re: [NSRCA-discussion] For Sale
> 
> Rex, would one of the .61's happen to be a Hanno Special?  If so, I would be interested.
> 
> On Fri, Feb 10, 2012 at 4:38 PM, Keith Hoard <khoard at gmail.com> wrote:
> Make a post on RCU and RCG Classic Pattern Forums about the .61 long strokes. . .
> 
> Keith Hoard
> Collierville, TN
> khoard at gmail.com
> 
> 
> 
> 
> 
> On Fri, Feb 10, 2012 at 4:35 PM, Rex <trexlesh at msn.com> wrote:
> Folks
>  
> I am posting these items for a friend that has too many toys...he's pretty much electric now.
> If you find something that interests you, email me off list for the contact info.
>  
> Shinden (NIB) latest version... Red/Blue Scheme $1200
> YS 140L (NIB) $380 shipped
> YS 91FZ (NIB) w/muffler $300 shipped
> OS 140RX (NIB) $400 shipped
> " Header $50 shipped
> " Exhaust Muffler $200 shipped
> Mintor 170 w/2 plug head and header NIB $400 shipped
> (2) MAX OS headers (both) $50 Shipped
> Aeroslave Mintor Exhaust Muffler ?
> OS 140 Mixture control Carb ?
> 3 cases Magnum fuel ?
> He also has quite a few 61 longstrokes, plus the headers and Hatori Exhausts.
>  
> Rex Lesher
> 
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> 
> -- 
> Scott A. McHarg
> 
> 
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