Brodhead Pietenpol Association

Original Posted By: "Douwe Blumberg"
I need to finish my engine conversion. I have the manifold and exhaust leftto do. A few years ago the BPA newsletter had a note from a man who hadinstalled the water heated plate from a Ford Falcon between the manifold andcarb. I can't relocate the article and am wondering if anyone out there incyberland would be familiar with this approach. I have the water heatedplate from a Falcon, but the holes don't come close to lining up. I wouldlike to contact the person who used this approach to learn how heaccomplished the mounting. As much as the rpms drop when you pull the carbheat on an aircraft engine I wonder if the same effect occurs on the "A"engine when it is constantly fed warm air for combustion. Is it possible tokeep the manifold heated enough to stop icing but still use cool air intakefor greater power?Carol and RalphRaymond________________________________________________________________________________

Original Posted By: "Ralph"
Ralph,Carb icing doesn't occur in the manifold but in the carburetor itself, atthe venturi. It is the adiabatic cooling, caused by the drop in pressure atthe venturi, that causes the moisture in the air to condense out of theairflow and freeze, when there is enough moisture in the air. Carburetorheat raises the temperature of the incoming air to the point where the icemelts.If the carb heat is left on all the time, carb icing can still occur, but ata much lower ambient air temperature than normally. If that happens, youdon't have any carb heat left to melt the ice...bad.The RPM drop you get when you use carb heat is caused by the decreaseddensity of air that is taken into the cylinders, the same effect that isfelt, to a certain extent, on a hot day.Having the water-heated plate would still heat the air going into thecylinders but would probably not remove any ice formed in the venturiupstream of the plate.So, having the plate hot all the time would rob you of power and wouldprobably not do any good as carb heat.Mike Hardaway----- Original Message -----

Original Posted By: "Don Morris"
The heated carburetor idea sounds good but there isn't near as much aviaitonhistory with liquid cooled engines as aircooled. I guess I'd like to see alot of other people successfully use the water-heated plate idea before I'mwilling to risk an off-field landing to prove such a concept. Does anyonehave much AIRCRAFT experience with a heated carburetor plate in lieu of carbheat air? (Doesn't have to Model A Piets.)My old datsun 510 used to ice up all the time in rain once the manifold heatduct fell off, but I'd just coast to the side of the road and in 2-3 minutesthe ice would be gone. I wouldn't want to exercise such a care-freeattitude in an airplane.Mike Hardaway----- Original Message -----

Original Posted By: Rick Holland

Original Posted By: Jon Botsford
From my one person experience so take it for what it's worth:Contrary to all the folk lore, Gas welding is not that hard to learn. I didn'twant to weld my fittings but after a year of asking around the EAA people noone was interested in helping me weld or even help teach me, wonderfully helpfulpeople these EAAers.. So I took a beginning class at a craft center here intown (it wasn't that good of a class) I bought some books and the EAA tape onwelding (It was only OK, thankfully Chris Bobka helped me get it for half priceso it was worth the money. He's good EAA type people only wish he live closer.Hey Chris want to move to California,? the house next door to me is forsale, 1020 sqft 3bd 1 1/2 bath "only" $325,000. I'd even let you borrow my tools.)Anyway, I bought a gas welding setup for $350 bucks and started practicing, after half my 40cf (?) smallish tanks I was making good welds. After the tank was gone I was comfortable with my welding ability. Probably not always perfect but I'm confidant they are good welds. It's not really that hard and I am glad I learned how to weld. Now I want to learn how to do real metal work (I never took metal shop class in high school). A good article to read is called "Zen and the Art of the Weld Puddle", by Budd Davisson. http://www.airbum.com/articles/ArticleZenWelding.html I have recently purchased a smaller welding torch, a Meco from Tinmantech.com, it works better then my Victor knock-off.Don't be afraid of welding like I was. It's really not that hard to learn how toweld. Oxy-Acetylene is a very good way to weld both 4130 and Mild steel andcheaper then TIG. You shouldn't braze 4130 (yes it can be done) but if you arebuilding to the plans you can braze the mild steel BHP calls for. What yousay? Yes, BHP does not call for 4130 everywhere (he actually calls 1430 cro-mollyI think) and that's ok because he designed it for the mild steel and it wouldbe plenty strong. I used 4130 because I didn't know better. Oh well, atleast it will be stronger.Chris TracySacramento, CA----- Original Message -----