JD G carb on JD B

G T sounds like an engineer. He didn't say it wouldn't work. What he said is it wouldn't be as efficient as if it were sized properly. What he gave were facts. I agree that Mike might as well give it a swing since he already has it. Could be a lot of fun. (Hey, discovery is fun!) This is like putting a 850 Holley double pumper on a 3.8L Buick. It may work, but how well? Or like puting a blower on a big v-8. It will make a ton of power, but the blower will suck up a lot just to run. Efficiency. Drive on!

A particular sized carburator has an optimum cfm rating range where air velocity causes the ideal delta P across the venturi (s) to pick up fuel and carry the fuel mist suspended in the airflow. Too little velocity & mixture metering becomes erratic with fuel droplets falling out of suspension causing puddling on the port floors. This is a commom cause of intermitent bogging or missing when the engine is lugged down. A smaller carb would have made more torque/power. Of course a too small carb will restrict flow & reduce volumetric efficiency particualy at high RPM. The B or any other engine depending on it's configuration will have three ideal carb sizes. One each for peak torque, peak HP & best compromise. The G carb family is a stretch on a stock B, better one of the A carbs.

This is why you can not trust what you read on this forum. Too many people that think they know everything trying to make themself look smart.

I have tested a B John Deere with the stock carb and then a G carb. I hate to make you sad, but the G carb had more power than the B carb from Max RPM to as slow as it would go. What is so hard to belive about that? If fact I have put G carbs on four Bs. I have also put A carbs on B. The A carb and the G work about the same. I'm just confussed why this upsets you so much? It is possible that someone might know a little more about this subject than you. Is that all that bad?