throttle body size recommendation

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Nov 6, 2010 | 06:08 PM

bigskyroadglide

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From: Mountain West, Big Sky Country

throttle body size recommendation

in the process of building a 110. Standard HD kit, having the cases bored along with crank balanced trued and welded by revolution performance in WI. going to be running andrews 54 cams, with 9.5 to 1 compression. Electronic compression release valves. my decision point is what to do with TB. have the stock 46 bored to a 48 by Horse Power Inc (HPI), buy the 50mm from harley or buy a 51mm from HPI. looking to top out around 110/105 torque and HP. Using a thundermax with auto tune for ECM. what would you do? really want to keep the cruise control but know the stock injectors probably will not be up to the task. the 50MM is the cheapest route, but not certain cruise will work with the 50mm. HPI says their bore of the 46 to the 48 will flow more than a HD 50MM and they can up grade the injections to 4.9gm. thoughts? i am undecided but really want the cruise to work.

also, this is an 07 cable bike

Last edited by bigskyroadglide; Nov 6, 2010 at 06:30 PM. Reason: add info about bike year

Nov 6, 2010 | 06:29 PM

dawg

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From: Vermont

If this is on your 2010, you don't have a 46mm throttle body

Nov 6, 2010 | 06:32 PM

bigskyroadglide

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no it is on an 07 i bought with the engine cases busted. recent purchase

Nov 6, 2010 | 06:34 PM

dawg

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From: Vermont

Also remember that bigger is not always better on the TB unless building something that requires it. I'd go the HPI route

Nov 6, 2010 | 06:44 PM

bigskyroadglide

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kinda was what i was thinking, the 51 at HPI is approx $700, but having the 46 bored to a 48 with upgraded injectors comes out to about $350 or the same as the 50MM from HD. If i am reading the cataloge correctly, the 50MM does not work with cruise control. is this your understanding?