Technical Embarrassing gasoline smell

I really do. ty!

 

Some great info here and a happy camper...bonus... I will be applying some of this tech next year when I get Ole Stinky out again...

 

I had a lot of carb issues with my 94's when I was a noob to flatheads. I'm still a noob but better at it now and there is a pretty steep learning curve. I'll share some of what I did to get to comfortable. Dual 94's on my 59 AB flatty. Stock-ish cam with high comp. heads. Putting out 150 psi on compression test on all 8. Charlie at Vintage Speed was VERY helpful. His power valves are the ONLY ones to buy as the new 94 power valves are indeed machined differently than what came on these carbs back in the day. They simply will not seat flush. Some guys use a flexible nylon gasket to make them seat. Charlie actually machines the "slope" off the mounting surface so they sit flush. Use his nylon gaskets. I'm running 3.5 power valves and 46 jets. Stock jets were 51's. I kept on going smaller and smaller until it was right. Idle screws turned out 1 1/2 turns. I use NGK 6BL plugs set at .030. I have a Pertronix setup inside my crab dizzy. Pertronix is NOT an HEI ignition. It is electronic but it is not "high energy ignition". It's going to hit hotter, but not extended tip on the plug and gap at .040 hotter. My 59AB had a stock gap set at .025. If I ran the gap larger it ran like ****. I increased it to .030 when I installed the Pertronix and it runs great. Good core 94's are essential. When I rebuilt mine, I was lucky to find NOS needles and seats (I HATE Viton tipped needles). Ethanol gas WILL cause those Viton tips to swell over time. Set your floats according to the specs on the rebuild sheet. Fuel pressure gauge after the regulator set at 1 1/2 lbs. Do NOT use a fluid filled pressure gauge (ask me how I know). You say you have rebuilt carbs multiple times. Do you run all the parts through an ultrasonic cleaner? Cheap ones work great for these carbs. Play with the winter/summer/normal setting on the side of the carby's for the accelerator pumps. I set mine to the leaner setting all the time and it made a huge difference in performance. These engines were designed to run on ONE carb. Running them on two or more is going to make them run somewhat rich at idle regardless of what you do, especially with that 3/4 race cam you're running. It's old technology. You're going to have some gas smell. Period. You can minimize it, but it's never not going to smell. If you don't like it, buy a Tesla. Reading plugs on ethanol gas is a bit tricky but they should still read clean. I clean my plugs every 500 miles and replace them every 2000-4000 just for ****s and giggles. I change my oil every 1000 miles. I use Lucas upper cylinder lubricant as a fuel treatment. It also works as a lead replacement (see their website because that feature is NOT on the bottle) and prevents the float needles from sticking (yes, I had that issue before the Lucas). I use Star-Tron Starbright fuel treatment as well to counter the ethanol in the gas. All the above has brought me to a comfortable place with my flatty.

Aren't flatheads fun??? I think so. Nobody goes, "Oooooh" when they see a small block Chevy. Hope the above helps.
Andy

 

^^^^ great information here. Thank you.

interesting (to me) about the smaller jet size.
All other information that I have read suggests stock jets for twin ‘94’s on flathead.
When I decreased the jets on my 1&1/16 twin carbs on 283 sbc from stock 57 to 54 it ran better.
Currently running 4.5 pv on same set up but haven’t used a vacuum gauge yet.