I tried flow bench testing it years ago, but after I thought about it, I decided it was inconclusive, as on the flow bench, theres no way to simulate all the pulsing and backwash that happens in a running motor. One thought I had on the subject is that end gases could be pumped into the open end of the passage on the exhaust cycle, and be drawn back into the cylinder on overlap as the intake valve starts to open. Dyno testing would be the ultimate test.
Of course the exhaust heat riser on the Ford only connects to one exhaust valve per head. On the Chrysler and Pontiac and other heads, the riser connects the two center cylinders on each head. Which may promote mixture dilution. Or as many fuel racers believe, popping back through the blower. Cement might be fine. It would scare me. And we don't really have furnaces here. Or cement for furnaces.
TR I like the picture of Webers on a Chrysler hemi. However there are a lot of intake manifold choices for the Chrysler. The Desoto gets no love because of the lack of intake choices. In my case if you add the issue of hood clearance then its really bad.
You could also slant the carbs toward the center of the engine some to give you more clearance for the hood. I've thought of that design myself, it sorta' copies the look of some mechanical injectors I saw on a 440 Mopar once. Since the ram tubes are staggered from the ones on the carb on the opposite bank, you can lean them over quite a bit and gain a lot of clearance. Then you eliminate the dogleg in the intake port and have a straight shot into the head.
I built my own 3 duece intake for my 341 and used that remote thermostst housing. The biggest problem with that setup was from a cold engine start. As the engine warmed up heat only trickled up through the rubber return hoses. Engine heat would build to well over 210, as much as 240 before the thermostat would get enough heat to open. Cool weather was worse than hot weather. The solution was to drill the remote housing for a 1/8" pipe thread and use a small hose barb and hose to the water pump. Shown in the 2nd picture. From a cold start the engine warmed to 180 degrees and never had the temp spike. A small bypass hose. <!-- attachments --><!-- attachments -->
Would it have been easier to start with a Chrysler Weber intake, and modify it for your Desoto? Basically cut the flange off and add a Desoto flange?
I don't know the answer to that. I considered it I didn't have one to play with. I was a little leery to buy one then cut it up.
I got the idea from an article posted on the HAMB about 6 years ago. I don't know if it is still on here so here it is if it is any value to you.
[/URL][/IMG] I just got my manifold back from the machinist. Welded the two pieces to the base. I can then cast them as one piece and save me some cost.
It's taken a while but I finally got my intakes cast up. This is a unmachined casting. I will probably be a few weeks but I will post a pick after I machine them and polish them.
Being that the carbs are side draft, remove everything but the butterflies, and go with a Megasquirt type injection by installing injectors in the manifolds. It will keep the Weber experts guessing if they can't see the injectors. Just a thought.