ClassicCar

Hey Everyone, I am new to the site and to flathead engines and mine is starting to give me a flat head....



My vehicle is a 1956 Willy’s pickup 4x4 with all original drive-train except somebody swapped the original four cylinder for a straight six flat head out of a 1953 Studebaker Champion. When I first got it there was an exhaust valve in the second cylinder that was stuck open. I took the off manifold, the head off, oiled and worked the stuck valve until it was free, and while I had it apart I checked and cleaned all the valves, pistons, cylinder walls, etc (everything looked really good) and put it back together (also running 60lbs compression per cylinder). Once I did that I put new mechanical fuel pump on it and rebuilt the one barrel carburetor and fired it up and the engine runs like a dream. It sounds good, it revs up and idles great, absolutely no hesitations or misses or anything (even got the heat riser in the exhaust side of the manifold free and working properly). As soon as I shift the truck into gear, it falls on its face and has absolutely no torque. Even with shifting the transfer case into low range; it is a little better, but still really lacking in get up and go. The truck has 4.88-1 axel gear ratio and it currently has tires on it that are 30 inches tall.



I realize that my truck will never be worth anything as a collector’s item but the thought of it, and keeping it at lest time specific as far as technology means a lot to my Dad and I so we really want to keep this flat-head six but we are out of ideas. One thing I do know is when I took the manifold off the original gasket ripped so for test purposes I used high heat silicon to goop it up (this was before we knew it ran). The silicon did not take and I know there is a lot of air coming in and escaping (seriously throwing off the air fuel mixture on the intake, and the back pressure in the exhaust) but would that be enough to cause absolutely no low end power?



Thank you in advance for your help.



Calico