---------------------------------------------------------- Stratus-List Digest Archive --- Total Messages Posted Tue 05/19/15: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:33 PM - Low power @ full throttle (jpkarnes@comcast.net) 2. 05:45 PM - Re: Low power @ full throttle (ron hansen) ________________________________ Message 1 _____________________________________ Time: 03:33:43 PM PST US From: jpkarnes@comcast.net Subject: Stratus-List: Low power @ full throttle Hi all, =C2- I must convince that I'm at a loss to figure out why I can't reach full RPM 's @ full throttle.=C2- It was running fine until I performed several upg rades including: =C2- 1.=C2- Switched the .25" rubber fuel hose to 3/8" aluminum tubing. 2.=C2- Heads retooled by Ram. 3.=C2- Carbs overhauled. =C2- It seems to run fine until about 3K RPM and then "surges" up and down a bit .=C2- Any more throttle than that and it runs crappy.=C2- The timing is @ 32 deg @ 4000 RPM (with no prop on).=C2- Any ideas? =C2- John K. ________________________________ Message 2 _____________________________________ Time: 05:45:21 PM PST US Subject: Re: Stratus-List: Low power @ full throttle From: ron hansen John, I don't think any of your changes should cause that problem directly. You will probably be lean and hot with the Ram head work and need to go to larger jets, but I don't think that would cause surging or roughness. It didn't with me, but I did have to go to larger jets for cooling. Ron at Ram dynoed my engine and he used 30 degrees BTDC at 4500 RPM and got just over 100HP. I don't know if that's significantly different than your timing or not. I had troubles with mogas (w/ alcohol) getting old and cruddy in a matter of weeks here in California until I switched to avgas. If all this work took a while your gas might have degraded and also your fuel line work might have left some particles in the lines no matter how careful. (Done that.) Some of the air passages in the carbs are no bigger than a toothbrush bristle so it doesn't take much to clog them. If you have EGTs you can see if both banks are the same. I added EGTs to sort out carb and cooling issues and continue to be glad I have them. Good luck, Ron Hansen 601HDS, Stratus/Ram Subaru On Tue, May 19, 2015 at 3:33 PM, wrote: > Hi all, > > I must convince that I'm at a loss to figure out why I can't reach full > RPM's @ full throttle. It was running fine until I performed several > upgrades including: > > 1. Switched the .25" rubber fuel hose to 3/8" aluminum tubing. > 2. Heads retooled by Ram. > 3. Carbs overhauled. > > It seems to run fine until about 3K RPM and then "surges" up and down a > bit. Any more throttle than that and it runs crappy. The timing is @ 32 > deg @ 4000 RPM (with no prop on). Any ideas? > > John K. > > * > > > * > > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message stratus-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Stratus-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/stratus-list Browse Digests http://www.matronics.com/digest/stratus-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.