B manifold compatibility

[carterbeauford]

I have a 1941 B but it has the later 4 11/16 bore, any way of telling if it was just bored out or is a late B block? I broke the exhaust manifold and had it welded, which was a mistake. I need to know which replacement manifold will fit my head and exhaust pipe, will this one fit?

http://www.davenporttractor.com/p-363-exhaust-manifold-for-john-deere-b-tractors.aspx



note the ARP manifold studs with the hex in the middle, makes installation and removal much easier.
 

[Dodgeit]

Your pic shows an all fuel manifold. The reference link is for a gas manifold that will work if you tractor has a serial# greater than 201,000.
 

[Jake Winn]

A late B block is different than a 41-early 47. It doesnt have the mounting holes drilled and tapped for the frame. The heads however will interchange along with the different style manifolds. I have a 45 B with 4 11/16 +.045 M-W style pistons, a Berry ground camshaft, head and block shaved down a bit, gas manifold and a late B carb. It makes about 26 HP on a pto dyno.
 

[carterbeauford]