I have an unusual 41 flathead v 8. I bought it supposedly rebuilt a long time ago. I have got it running only to find out more than 2.5 pounds of fuel pressure will over ride the seat in the carb and dilute the oil. Found out the hard way, isn't that always the way? While trying to get it to run right, I went back to basics and pulled the plugs and did a compression test. 165 to 175 per cylinder, pretty much even. All the vacuum I could get at idle was 13 inches. Maybe this was because of the diluted oil. I have made my living as a mechanic since 1970, starting on Fiats and ending with 747's and reassembled my friends 1934 Chevy Master sedan, so I am not without some skills and knowledge. The engine has 3 94's on an Edel brock aluminum manifold, a crab distributor, Offenhauser finned aluminum heads and tube headers. to make it simpler the secondary carbs are blocked off from air and fuel. The engine is apart to inspect the damage from the oil dilution. It's too cold to work in my unheated pole barn at the moment so I am trying to decide what's going on. I am going to go to Stromberg 97's if I can find one more to rebuild, have 2 already. when it gets warm enough, I will pull the heads and measure bore and stroke. There are no identifications on the cam. Imho this thing has been stroked and cammed. any thoughts?
The compression reading indicates larger than stock displacement and properly fitted heads to me, and the low vacuum indicates some sort of hot cam (unless there are other unrelated problems).
Strombergs like 2 pounds max. My particular Strombergs on my engine like about 1.5 pounds. I've got no idea what later carbs can stand.
I’d consider running just the two outer carbs and block the center one. The 94’s are good carbs also for your application. I agree drop the fuel pressure a tad.
I have run 3 94s on a 296 inch FH with straight linkage and no issues. I have 3 97s on my 286 inch FH.....progressive linkage....no issues. Fuel pressure at 2.5 psi. EDIT - Make sure you use a regulator that is accurate at low pressures.....most are not. Also use fuel pressure gauge in line to verify the pressure going to the carbs.
and check float height is correct, but you probably know that…. and what model of ‘94 is it ? They are all a little different.