Aircraft Carbs

I happen to have 4 of these Marvel Schebler HA-6 Side drafts laying around. I would like to see if anyone has used such things before. One would be used on a lycomings Flat 4cyl so I have been told.

I'm not a carb expert by any means and if someone knows these better I would appericate any input on possible use (other than planes and airboats)

I searched the HAMB and couldn't see anything but I might have missed it.













Cheers

 

I haven't used any except on the lycomming that I put in my corvair in the '70s.

I see no reason whay you couldn't use a brace of them on a banger or an inline 6. What is the throttle bore on them and what is the CFM rating do you know?

OK quick guestimate is that the throttle bore is 2.75 +/-

 

The thing about Aircraft engine carbs, such as you have shown, is that they are really simple devices. That means they have virtually no ability to automatically compensate for varying conditions. They do have a mixture control that allows manual adjustment of fuel flow by means of a cable or linkage. This permits adjusting for richness (or leaner) for full power mixture and/or atmospheric pressure changes due to al***ude.

In aircraft applications they tend to be run at more nearly constant throttle setting than in automobiles. It would seem to me that they would be better suited to racing use than street applications.

Ray

 

If you run an adjustable mixture, I'd recommend an EGT sensor and gauge. That would be cool to dial in the right mixture for a trip through the mountains or a long flat stretch of highway.

 

Not the best for auto engines as the are not ment to do anything fast. and they are ment to run at a constant rpm. Ment for about 300ci at 2500rpm.

 

Before you decide to use them, try pricing repair kits and other parts!

And no, we do NOT sell aircraft carb kits.

Jon.

 

At one time there were no high CFM automotive carbs. Because of that, here have been racer cars that used aircraft carbs. But I agree, it's not a good choice for a street car.

 

Non aircraft carbs of at least 600 CFM (on a 4-barrel scale) have existed since the late 1920's. These were two-barrel units.

Carter introduced a 950 CFM in 1963. (3 barrel)

Carter introduced a 1000 CFM in 1969. (4 barrel)

Jon.

 

I'm not familiar with those carbs, but I'll jump on the "it probably won't work well" bandwagon due to the general aircraft carb simplicity. They really only do constant speed stuff, no transients. It likely doesn't have any acceleration enrichment such as an accelerator pump, but you'll have to check. If it doesn't, the engine will stumble or stall every time you step on the gas quickly. You also may not be able to start the engine since there isn't a way to prime it with fuel. Carbureted aircraft engines usually have a separate priming pump that squirts fuel into the intake runners.

See if you can arrange a trade with an aircraft guy. You also might be able to turn them into throttle bodies for an injection setup rather than s**** them if you get ambitious and are hell-bent on using them.

-Brian

 

I just had some time to check and found out those carbs DO have an accelerator pump. Sorry for the confusion.

You'll still be limited in getting the mixture right across the whole operating range as it's a single main jet with idle bleed adjustments rather than a car's more complete series of circuits and adjustments.

-Brian