Forced induction and carbs

Are there any carbs that can be used in a blow through setup with either a turbo or super charger?

No carburetor which uses a float bole can be used with forced induction. You would have to use carburetors which are designed for the aviation industry and are force fed by a pump. Welbro is one company that makes force fed carburetors, but I am not sure what sizes they make and if you could fit the large square bodies on the engine.

i'm not the forced induction dude.it does look like this dude is blowing through float bowl carbs.


leon holmes

Maybe shoot these guys an e-mail

www.mrturbo.com/index.html

You can have forced induction through float bowl carbs. You do however have to build a sealed box all the way around them. Forgot what they called this, but it might be a gravity box? Anyways, building a sealed box around the carb insures that the same pressure being forced into the carb is found around the carb. Therefore the fuel in the bowls reacts normally and you won't blow gaskets/seals. It's been done for many years with race cars. Never really seen it on a bike though.

Where's da Plummen when we need him?

gershom wrote:

You can have forced induction through float bowl carbs. You do however have to build a sealed box all the way around them. Forgot what they called this, but it might be a gravity box? Anyways, building a sealed box around the carb insures that the same pressure being forced into the carb is found around the carb. Therefore the fuel in the bowls reacts normally and you won't blow gaskets/seals. It's been done for many years with race cars. Never really seen it on a bike though.

+1 on that. Seen 'em on old supercharged Datsun Z cars.

gershom wrote:

You can have forced induction through float bowl carbs. You do however have to build a sealed box all the way around them. Forgot what they called this, but it might be a gravity box? Anyways, building a sealed box around the carb insures that the same pressure being forced into the carb is found around the carb. Therefore the fuel in the bowls reacts normally and you won't blow gaskets/seals. It's been done for many years with race cars. Never really seen it on a bike though.

You can also boost reference the float bowls to equalize the pressure between the venturi of the carb and the float bowl of the carb.

To do this you also need a electric pump and a boost referenced rising rate fuel pressure regulator.

It can be done, lots of people have made it work. Might not be perfect, but neither is a drawthrough setup. It has it's own list of problems.

The best way to run a turbo is blowthrough with fuel injection. Not the cheapest, but the best,

gershom wrote:

You can have forced induction through float bowl carbs. You do however have to build a sealed box all the way around them.

Yep, Studebaker did it way back in 1957 when they wanted to make a really hot motor in a car called the Golden hawk. A big flex hose coming from the supercharger hooks onto the sealed enclosure that encases the carburetor.

Chevy used stock type carbs to turbocharge the engine in their corvairs. The exhaust driven turbo was set up to "pull" and the intake manifold and carb mounted on it and the turbo sucked through them and fed the engine. Made it easy to hot rod because they made aftermarket manifolds you could bolt right on that accomodated larger carbs.

www.turbomotorcycles.org/TMIOA/Bike_Yamaha_XJ650.html

XJ650 turbo had pressurized 30mm Mikunis. Might be worth looking into.

Thanks for all the replies, obviously there is no simple answer. So it looks like fuel injection or a custom manifold for a small Holley 4 barrel!! Glad I can tig weld.

maybe i will have to try a set of Mikuni flat slides with the bowl vents tied to boost, I really don't see needing more than 10 PSI so I would think the bowl gaskets whould be able to stand that small amount of boost.

DoubleDub wrote:

Where's da Plummen when we need him?

ive never tried it myself but thats why i took that picture of the zrx turbo when i was in monterrey ca.couldnt find the owner to get any details