Im finally back to work on my model A coupe with a Gmc straight six after about 7 years off. Since the original setup I have changed intake/ carb setup. When I originally set it up I had a 2 carb Nicson intake and mounted the engine by placing a level on the carb mounting surface. I have since put in a highly built 302 with a 4 barrel intake. This 4 barrel intake has a highly angled mounting surface. Do I have to try to re do my mounts to get this new carb level?? It’s gonna mess up a bunch with how tight all my clearances are. Please advise.
The only time that your fuel in your bowls knows that that carburetor is level is when you're sitting still. But I'm just thinking out loud.
I don't use the carb mount to level the engine, I use the crank center line. I try for 3 to 4° nose up from level of the frame datum line. I don't remember what publication I gained this from but it's how I've been doing it for 40 years.
Carb being level on level ground at ride height is a good thing to shoot for. Otherwise the carb operates mostly off kilter, but then it’s only less or more level when actually on a hill. That is not something to strive for. Is it feasible for you to have the 4 bbl manifold milled to reduce the carb angle to match your dual carb manifold? That would be what I would look at were I in your shoes. 302 Jimmy....yum, yum!
Carb is angled so when suspension is extended under accel it will be close to level then, at speed.... Sent from my SM-G900V using Tapatalk
How do you go up or down a hill if the carb has to be level? How far off is the angle? A few degrees won't make much difference. The problem with milling the manifold is you then have to fill and re-drill the carb mounting holes perpendicular to the new surface.
I've always set the with the carb mount surface level. All the bullshit aside, that is how it sits when you tune it in the garage including setting float level and worrying about how it sits for a few seconds under acceleration or on a steep grade is nonsense thinking unless it is a drag only rig or a hill climb only rig. Ideal float level while being tuned in the shop is going to take in hill and acceleration conditions as it isn't going to accelerate hard enough to uncover the jets nor is it going to be on a grade steep enough to uncover the jets.
No, for that few degrees, you really don’t have to worry about the studs. But if you are super anal retentive and you must have them perfectly perpendicular, put nuts on the studs and whack ‘em with a hammer until they are. One thing about the HAMB, no matter what the physics, or the proven principle that is offered as a guide, as sure as day follows night, some member(s) will argue with known facts. “.......I’ve totally ignored (fill in the blank) ands it’s always worked for me!”........
Maybe it won't work for you but the first thing I would do is turn the 4 barrel 90 degrees....way more efficient. If you want I'll photo my linkage which I made using parts from Kinsler Injection catalog and its cable actuated. Not what you want to hear but that intake is really restrictive.
There also used to be thin angle plates for 4 barrel carbs, maybe by Offy? Those just slipped over the existing studs. x2, and the hammer is ok, too.
Carb wedging plates used to be sold for marine engines. They may still be available? If not, add a spacer, and get it milled, if you can't live with it. You can play around with things on a spacer and not screw up the intake. That might be one thing to consider, if you ever want to use it elsewhere.