carb chioces

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Sep 18, 2011 | 11:06 PM

dongorgon

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From: sincity

carb chioces

Heads flow 270+, do i need makuni 45 with 237cfm or 48 with 270 cfm. stock carb cv40 flows 185cfm.

Sep 19, 2011 | 05:51 AM

roadkingharry

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From: Punta Gorda, Florida

Call Scott Palmer at Hillside,he's a good guy and forum sponsor and he'll give you some professional advice.They've done 100's of those builds. PALMER BROS.,HILLSIDE MOTORCYCLE & MACHINE, INC.,5225 S. MAIN ST., MUNNSVILLE, N.Y. 13409
315-495-6650

Sep 19, 2011 | 06:04 AM

oct1949

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From: 40 miles Northeast of Indy..

Ask the guy who did the heads, They usually know more than most members in here who don't know anything bout them.

Sep 19, 2011 | 09:40 AM

djl

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From: san antonio

Quote:

Originally Posted by dongorgon

Heads flow 270+, do i need makuni 45 with 237cfm or 48 with 270 cfm. stock carb cv40 flows 185cfm.

Are you both talking @28" or at @10"?

Sep 21, 2011 | 08:30 PM

dongorgon

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From: sincity

25" got directed to 45 makuni due my itty bitty bore and over size heads and cam per the head people . my indy siad the same . but im just throwing out there thanks

Sep 22, 2011 | 04:08 AM

FBFletch

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Joined: Dec 2005

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From: Hickory, NC

Quote:

Originally Posted by dongorgon

Heads flow 270+, do i need makuni 45 with 237cfm or 48 with 270 cfm. stock carb cv40 flows 185cfm.

If you haven't significantly increased the bore, you're probably better off going with the 45. If you're looking to make as much torque as possible you're generally better off sticking with the smallest carb that can get enough air and fuel to the engine so that it is not the limiting factor.

I just finished a 95 cu in built with very high flow heads (I'll have to call the engine builder to get the flow numbers) and it came down to a choice between a 42mm and 45mm. However, my intent was to build a street fighter and I was looking to crank out as much useable torque as possible.

Sep 23, 2011 | 11:49 PM

dongorgon

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From: sincity

Yes jumping on the 45 makuni band wagon trying to break the 100/100 mark .85.5hp/101tq right now hopefully the 45 takes me close to or over the goal. This thing already pulls from 0 to 120 + mph