Technical Carb--Level with engine --or the World

I am building a "Banger"- powered 30 Roadtster making my own intake manifold. Do I need the chassis on the wheels before installing the carb base? Not until then will I know angle of the carb base due to wheels sizes, front axle drop, lowered springs ect. Need to wait?

 

I would have it rolling, general rule of thumb is 3 degrees down however OEM banger with transmission and torque tube may be different, 100's of HAMB threads on this subject.

 

I would wait until I had as much together as possible. Especially ride height and rake. The sheet metal should be fairly balanced and settle everything straight down.

 

Most intakes are machined at a 3° rake, low in front, high in rear. That way, when the engine/trans are tilted down at the rear for driveline angle the carbs sit level.

I say most because I had an Edelbrock C355 3x2 that was factory machined at 8° for marine applications. That one was a head scratcher until I saw a really old Edelbrock ad that said "available 8° for marine installations" or something to that affect.

 

Carb should be level with the world. Engine angle determined by necessary driveline angle. Torque tube setups don't have driveline angles, so engine is level with the world, too.
Open driveline generally places engine at a 3 degree angle, so carb flange is at 3 degree opposite angle.

 

You're probably not going to start it until it's a roller so put it all together then see where you are with the carb angle. Even with big and little rubber rake it will probably be OK, if not a few angle shims under the carb and you're good to go.

 

"Probably be OK"? "Angle shims?? Why not set it up right, from the start, instead of adding a "bandaid" after the fact?

 

For your torque tube application make it level with the cylinder head, any angle in the carb base will look weird. Consider that vehicles are seldom level during operation, up and down inclines continually. As others have stated, if you are building a open driveshaft project the transmission down 3 degrees and axle pinion up the same amount is necessary for u-joint operation and not required with the single front u-joint solid mounted rear attachment of a torque tube. IMO it's not necessary for the intake carburetor base to be level to earth, it works just fine if level to the cylinder heads.

 

I would start with having the carb base at least 3 degrees pointed down toward the rear of the car. I think that should be good enought, I mean how many time are you driving on a 0 degree level road. You are always going up and down hills. With that being said, go with the 3 degrees pointed down toward the rear of the car.