I decided to finally do this mod I've been thinking about to my '53, dual carbs. I had two YFs and plenty of time. So here it is. I got two YF repop air horns that I'll tie into the original air cross over tube.

http://www.youtube.com/watch?v=sUMFx9gbDIQ

I like it ! Details on how you did it ?

The thought of a progressive linkage did cross my mind, but I decided to keep it simple. The fuel line is pretty far away actually. Is no different than where the float bowl of the WO would be. The fan also blows a nice breeze by it too and out the rear hood gap.

Kenny, I traced the gaskets to make my flanges and just cut some tubing with 45s on the ends. Putting the equalizer in was the hardest. You have to keep the two block flanges in the same plane as well as the carb flanges. I also used an Fhead exhaust manifold to keep it clean looking.

Yes, the reason is more power. But how does it make more power? Well, its not the delivery of more fuel, that would cause the engine to run rich and that would be bad. This is the gist of it. This allows the engine to breath better. It all has to do with these things called venturis, where the fuel and air mix and the amount of air flow. Try only breathing through a straw only while running or exercising. You'll notice it is rather difficult to keep up with the air your body needs. Same principle applies to an engine. By letting more air flow easily, you will have more performance. This is also why people put 4 barrel intakes on V8s and yank off the 2 or 1 barrels. The engine gets all choked up.

This is a very simplified explanation. There are a bunch more factors and such that I know a little about from working with my hit and miss engines. It is all very complex.


One other thing I noticed too is, it starts much better too. It started great before, but it is even better now! Usually when it is cold, I'll have to choke it and leave it half choked with the throttle on a bit until it warms up. However with the two carbs, I choke it all the way and it fires right up as soon as I turn the key and I can turn the chokes off all the way and it will stay running.   Then when it is warm, I can turn the key and it will fire up right away. Just the way I like engines to start.  

If you look closely, there is a piece of wire between the two carbs and at the second one, you can see the choke cable sticking out. At the rear carb, there are two pieces of wire going into the cable clamp for the choke.

Yes, the tubing is cut and 45s and welded to make a 90. I thought about a bend, but it is so tight there that I don't think it would have worked. Haha, I don't think I'll be getting aluminum ones made anytime soon.  That would cost a small fortune I think!

But my engine is Pontiac blue! That is better than Chevy orange!   

Nice work Nate.  I was thinking the same thing as Carl on the fuel line and manifold heat.

I want to see your air horns.

Tim

Here's the air horn. Nothing too technical. Just two Fhead air horns welded together and a piece of old cross-over tube sticking out.

Me too! I'm hoping I can this weekend. The machine shop said my OD shifter forks should be done sometime this week. Hopefully it will be cold this weekend and my road will be frozen.