Turbo question

hello all,
Im in the process of putting a turbo on my farmall 350 as a personal project. I have the turbo mounted and when i tested it today with a dino to see what would happen she puttered and died as soon a load was applied. any ideas on why this may have happened? not enough fuel, too much fuel? the turbo is set up to boost and stuff the carb rather than pullin the fuel air mixture out of the carb and into the turbo.
Thanks

A carb operates on principles of vacuum. When air pressure is put into the air intake there is no longer vacuum inside to draw fuel from the main jet. Instead air was probably pushing down the main jet.

I talked to the people at keystone turbo (the people who make them for m's) they said they were having trouble finding a turbo to suit the engine and they were have turbos custom made.

I think the turbo must suck fuel from the carb.

shoot the guys at keystone turbo a call, see what they have to say.

I just thought of your possible problem. Since it is a blow through type turbo set up you will need a high pressure fuel pump and regulator. I think this may be where your problem lies.

Just a thought. Would it help if the entire carburetor would be placed in the discharge tube of the turbo? Then the venturi in the carburetor would still create the pressure DIFFERENCE, which is required for the carburetor to work as intended.
Thanks, Hendrik

referencing seeing 1957 studebaker car with super charger from factory and talking with owner. entire carburator was in pressurised air box like hendrick mentioned also fuel in let pressure must be more than boost pressure or gas would be blown back threw fuel line

You stated that you were stuffing the carb. I take this to mean you simply removed the air inlet plumbing from the air filter and connected the turbo discharge to the inlet if the carb. As previously mentioned this will not work since the carb fuel bowl is vented and the venturi is now being pressurized. Typically the entire carb is placed in a sealed box and this box is pressrized by the turbo or supercharger. The throttle, choke and fuel lines must be sealed where they enter the pressurized box. As mentioned this is the approach used by Studebaker, Ford and others for the McCulloch/Paxton supercharger equipped models.

Once the carb is placed in a pressurized box it operates the same as when the atmospheric pressure (barometer reading) changes. That is to say the mixture will be richer at low atmospheric pressure and more important it will be lean at high atmospheric pressure. If you keep the bosst pressure to a few Psi you can simply set the mixture on the rich side and live with it being rich when not on boost. If you intent to run higher boost pressures you will need some way of adding more fuel at high boost. The reason this happens is because a carb can not determine the density of the incoming air - the turbo pressurizes the air which increases the density. One final note the fuel pressure must be higher than the maximum boost pressure otherwise fuel will not enter the pressurized box.

Should you decide to add the carb to the inlet of the turbo (suck through) you will need a turbo designed for this application. The turbo oil seals must be designed to operate under an inlet vacuum which of course is not present on diesels.

Ken... Great explanation of the requirements! Now I can say I learned something today. Thank you

The 350 carburetor is a good candidate for adding a turbo because the fuel bowl vent is located in the air intake before the choke plate. There is no external air vent for the fuel bowl. There is no reason to mount it inside an air box since the whole carburetor is exposed to the same turbo pressure.

Pat-CT has the correct answer. You need to pressurize the fuel entering the carburetor to above the maximum turbo pressure or you will run out of fuel in the fuel bowl. One thing you will have to watch since the fuel bowl will be pressurized is if you have too much boost you may collapse the float.

I have a turbo on my Super M and it works very well, Im making 98 horse at 540 PTO RPM. You have to have the Turbo AFTER the carb so that it pulls air through the carb rather than pushing it. What is happing is that you are pressurising the carb and it is basiclly running out of feul. Get the turbo pulling air through that carb and it should work excellent for you. Keep use posted

I would definitely put the turbo after the carb on a gasser. You do not have to pressurize the carb, and the turbo provides additional atomization of the fuel.