I have read some interesting discussion regarding the various A carbs. Could not find anything comparing the Marvel Schebler to the B Zenith. Background. I am looking to increase the power a bit of my current A. Engine is a low mileage overhaul as purchased. Per receipts, counterbalanced crank, lightened flywheel, V8 clutch, Aries muffler. Standard A cam, A intake, standard head. I intend to replace the head with a 5.5 or 6.0 HC head. Question is, with all other parts as described, Marvel Schebler carb or the B Zenith with the A intake opened up to match? Thanks for the input!
Marvel Schebler vs B Zenith
- Thread starter gwillford
- Start date
Ordsgt
Senior Member
I do not have any personal knowledge of the B Zenith but have heard that properly mated up to the intake you get a couple extra horsepower. I love the smooth running engine I get from the Marvel and do not want to trade that for 2 horsepower. But we all have our likes and dislikes and it is your car. You would probably notice the most power from bolting on a 5.5 or 6.0 compression head. A better cam would get you a better Touring engine but is far more involved in installing
mcorrell
Senior Member
I like my rebuilt B carb, but it took some doing getting it tuned correctly. I purchased new jets from Snyder's and found most didn't match the oe hole sizes posted online. I soldered and redrilled the oversize jets and drilled out the undersized jets. As the oe B has a float valve set up for a fuel pump and the Model A is a gravity flow system the float valve has to be enlarged a bit. Again I got a new one from Snyder's that I was able to drill out to about .108" and carefully deburred the seat. It works great and I can feel some power increase over the Tillitson X carb that was on my car
1930artdeco
Well-known member
My experience with a Model B is that the MPH goes down but then again my engine may not have been the best at that point in time. Had plenty of power- even w/o boring out the manifold and did not stall like the A Zenith. My Marvel seems to be the best of both worlds. Good MPG and power but I also have a 'B' cam and a 5.5 head.
Mike
Mike
RENNERS CORNER
Member
OK the thing about more power is that it typically takes more "fuel" but you can't just increase the fuel you have to increase the air also, and the only way to get more air is a larger throttle bore and the B zenith has a larger throttle bore.
Of course the B with its power jet circuit is probably going get worse gas mileage, you're not going to get something for nothing.
The marvel is a great carburetor though, it actually was originally released by Ford as a service replacement to be installed by the dealers in 1948. It's only downfall is warping which is easily fixed with a file.
I make or have every part for the Ford released Marvel Carburetor.
Of course the B with its power jet circuit is probably going get worse gas mileage, you're not going to get something for nothing.
The marvel is a great carburetor though, it actually was originally released by Ford as a service replacement to be installed by the dealers in 1948. It's only downfall is warping which is easily fixed with a file.
I make or have every part for the Ford released Marvel Carburetor.
McMimmcs
Well-known member
You not only have all the carburetor parts but you have a great reputation on this site. Regards, Wayne
RENNERS CORNER,
I have an assortment of various Model A carburetors but I'm a devout Marvel fan and am in the process of rebuilding 10 of them right now. Can you elaborate on the parts differences of the "Ford" version of the Marvel as used for replacements? I would appreciate any photos/parts drawings, etc. Thanks in advance for any info.
*Due to the high cost of the GAV/choke driver parts for the Marvel compared to the Zenith, I have begun modifying Zenith GAV/choke driver assemblies for use in the Marvel that fit nicely and are working quite well. I'm not too concerned with authenticity just trying to save some $$$.
I have an assortment of various Model A carburetors but I'm a devout Marvel fan and am in the process of rebuilding 10 of them right now. Can you elaborate on the parts differences of the "Ford" version of the Marvel as used for replacements? I would appreciate any photos/parts drawings, etc. Thanks in advance for any info.
*Due to the high cost of the GAV/choke driver parts for the Marvel compared to the Zenith, I have begun modifying Zenith GAV/choke driver assemblies for use in the Marvel that fit nicely and are working quite well. I'm not too concerned with authenticity just trying to save some $$$.
alexiskai
Well-known member
It may have been adopted by Ford in 1948, but Sears was selling it in 1946.
Synchro909
Well-known member
Yes, a different cam shaft is more involved than changing the carburettor but not by as much as many people think. It can be done without removing the engine - I've done it 3 times.
Great information and you guys have the BEST carb parts!
Terry NJ
Well-known member
Before you look at the B carb. with it's 1 1/4" bore as just a firehose for gas, lets look at the over all engine. All those 200 cubes, 3 + liters are sucking gas though that tiny 1 1/8" hole, you just know it been starving for fuel all these years. Add to that the highly restrictive interior surfaces of the manifold and you can see the problem. The additional HP that is picked up is just under 4 HP or almost 10%, say 8-9%. Pretend this was a Corvette and you increased it's HP by the same percentage. You'd be adding probably around 30 to 38 HP! Much more respectable! Now, let's say you add a "Head" say 5.5 or 6.0. CR. Maybe you are putting a little more fuel into those 50 cubes, but your'e extracting more power out of it by compressing it more. Hence, less gas is needed to achieve what you were getting before. I hope I answered your concerns about this.
Terry
Terry
