Methanol jetting

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Retroboy

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Has anybody run a Methanol carb here. NA Carb very lite car. I just got a BLP 750 from a work mate which come off a speedway car SBC running at around 7,000 has 144 jets front and rear AND power valves. Seems mega rich to me?
 
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That might be ok, depending on the carburetor. A lot of the ones I worked on had holes drilled in the metering block just above the jets, so the jet sizes were smaller. Make sure you have enough fuel volume and pressure, usually use twice as much as race fuel. If you can’t build any engine temp, jetting might be too much. All the drag racing carburetors don’t run a power valve that I have worked on.
 
Sorry I’m not much good to you as I haven’t ran a power valve since the 1970’s. With that being said I run 5.5 pounds of pressure and in my old 850 Holley ran 150-152’s depending on the time of year. Number 10 line front to back with number 8 feeding the carb. I’ll try to look today to refresh my memory on what I have in my new 1000 cfm APD carb.
 
That might be ok, depending on the carburetor. A lot of the ones I worked on had holes drilled in the metering block just above the jets, so the jet sizes were smaller. Make sure you have enough fuel volume and pressure, usually use twice as much as race fuel. If you can’t build any engine temp, jetting might be too much. All the drag racing carburetors don’t run a power valve that I have worked on.
Thanks Mate. The hole in the metering block is what was done years ago so you can reuse your old Holley jets without going to buy a whole bunch of bigger methanol jets. When I ran injection on meth I used to restrict fuel at idle to build heat, so with a carb I don't see why I can't intoduce air into the manifold so artificially leaning it out to build heat. Funny with Meth you try and keep the engine warm between rounds - the opposite to a petrol engine you try to cool down.
 
Sorry I’m not much good to you as I haven’t ran a power valve since the 1970’s. With that being said I run 5.5 pounds of pressure and in my old 850 Holley ran 150-152’s depending on the time of year. Number 10 line front to back with number 8 feeding the carb. I’ll try to look today to refresh my memory on what I have in my new 1000 cfm APD carb.
Cool thanks. Is that a small block ?
 
172’s the whole way around on my 1000 cfm. I leaned it out 4 jets sizes right out of the box from APD and I must have hit it close the way it’s been running. Hopefully I will check my egt readings this week.
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