Engine CFM and thinking ahead

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   ok guys.  slowly working on my puller build and looking into carburetor requirements/mods that may be needed down the line. 
A stock UM engine (318) at rated 1200 rpm and 80% volumetric efficiency(which is high im sure)  is 88 cfm.  not accounting other variables.
The industrial tractors had an optional 1800 rpm governor which comes out to 133 cfm
My build with 10% over factory ag tractor rpm at 1320 rpm comes out to about 133 cfm

These tractors used the zenith K5 carburetor. With a slightly massaged intake can i assume this setup would still be tuneable since the cfm is relatively the same or am i comparing apples to oranges here?  could we assume jet adjustments and/or a change to larger venturi would work?  

I am diving into the deep end here and havnt been swimming very long.

Edited by CAL(KS) - 24 Jul 2019 at 9:18am

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CAL(KS) Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 18 Sep 2009 Location: Chapman, KS Points: 3786	Post Options Post Reply Quote CAL(KS) Report Post Thanks(0) Quote Reply Topic: Engine CFM and thinking ahead Posted: 24 Jul 2019 at 9:17am
	ok guys. slowly working on my puller build and looking into carburetor requirements/mods that may be needed down the line. A stock UM engine (318) at rated 1200 rpm and 80% volumetric efficiency(which is high im sure) is 88 cfm. not accounting other variables. The industrial tractors had an optional 1800 rpm governor which comes out to 133 cfm My build with 10% over factory ag tractor rpm at 1320 rpm comes out to about 133 cfm These tractors used the zenith K5 carburetor. With a slightly massaged intake can i assume this setup would still be tuneable since the cfm is relatively the same or am i comparing apples to oranges here? could we assume jet adjustments and/or a change to larger venturi would work? I am diving into the deep end here and havnt been swimming very long. Edited by CAL(KS) - 24 Jul 2019 at 9:18am
	Me -C,U,UC,WC,WD45,190XT,TL-12,145T,HD6G,HD16,HD20 Dad- WD, D17D, D19D, RT100A, 7020, 7080,7580, 2-8550's, 2-S77, HD15

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CAL(KS) Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 18 Sep 2009 Location: Chapman, KS Points: 3786	Post Options Post Reply Quote CAL(KS) Report Post Thanks(0) Quote Reply Posted: 25 Jul 2019 at 7:47am
	No opinions? I realize this is kinda unknown territory here but if a 45 carb can feed nearly double the oem cubes surely the larger K5 can do what im asking here? Not sure there would even be another option with the way the carb is operated from governor linkage anyway.
	Me -C,U,UC,WC,WD45,190XT,TL-12,145T,HD6G,HD16,HD20 Dad- WD, D17D, D19D, RT100A, 7020, 7080,7580, 2-8550's, 2-S77, HD15

frnkeore Members Profile Send Private Message Find Members Posts Add to Buddy List Silver Level Joined: 07 May 2019 Location: Southern Oregon Points: 362	Post Options Post Reply Quote frnkeore Report Post Thanks(0) Quote Reply Posted: 25 Jul 2019 at 12:19pm
	I have no experience, in tractor carburetion but, you math seems right and you should be able to set the A/F ratio for best power, if it has a external adjustment. If you'd like a suggestion of how to get the A/F setting w/o a dyno. You can do that with a ox sensor.
	Frank 1959 D17 Series I #24001+, '59 D14 '55 & '59 Ford 850 & 861 Ferguson TO 35 Deluxe, Oliver 70 and 5 more.

CAL(KS) Members Profile Send Private Message Find Members Posts Add to Buddy List Orange Level Joined: 18 Sep 2009 Location: Chapman, KS Points: 3786	Post Options Post Reply Quote CAL(KS) Report Post Thanks(0) Quote Reply Posted: 25 Jul 2019 at 12:50pm
	good point. thank you, I will need to drag something around to load it as no pto LOL
	Me -C,U,UC,WC,WD45,190XT,TL-12,145T,HD6G,HD16,HD20 Dad- WD, D17D, D19D, RT100A, 7020, 7080,7580, 2-8550's, 2-S77, HD15