gosh I wish there were a "settled" solution, after all these years it still seems like "trying things" and owen's thought on "rebuilding every 300 hours" I took to mean the top end, and in particular it seems to me that temperature is the killer.
with such a tight thermal margin as Mark mentions 400 degrees CHT on departure, then one wonders how the turbocharged offerings do with 25% more power produced through the same heads. and one wonders also if the revmaster heads with the improved alloy and hemispherical chambers are the durability solution, or not. finally, I wonder how Mark with all the experience cant get CHT lower with more /different ducting? On Tue, Jun 21, 2016 at 7:31 AM, Mark Langford via KRnet <krnet at list.krnet.org> wrote: > To add to the insightful post that Owen Hughes (SVD) wrote yesterday day > on VWs, I would avoid the Mofoco heads. The photos show lots of fins, > and that's great, but what they are lacking is cooling air passages, I > mean almost nothing. If the air's not flowing through the fins, they're > going to run hot. I'm looking into this same subject lately, now that > it's gotten hot and I fly in the 90's most of the time, and I'm tired of > seeing 400F when I'm only 500' off the runway on the first flight of the > day. I ran across a photo over the weekend from a Dec 2010 Hot VWs > article that showed bottom views of 18 heads they reviewed, and > Fomoco's weren't so great. On the other hand, the "Chinese" heads were > awesome, lots of daylight between the fins, and by most accounts I've > found, the quality is very high, and the price quite reasonable. DRD > Aircooled sells them, and I plan to order some tonight. Whatever you > buy, make sure you get stainless valves! > > Another good chart that wraps up a lot of VW head details is at > http://www.thesamba.com/vw/forum/viewtopic.php?t=573099 > > Mark Langford, Harvest, AL > ML "at" N56ML.com > www.N56ML.com > > > > _______________________________________________ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options
