40 carburetor

[Moose]

We just re-built a 40 with a little extra for pulling. I need a new carburetor but I need one that will handle approximately 35 horsepower. Do I need to stick with the TSX530 or go with a new zenith? Or is there another updraft carb that would work better? Thanks in advance.

 

[CPeter]

Be sure the bore size of the carb matches the manifold as the turbulance caused by a mismatch will not help. Also, 40 and 420 manifolds are different. The ports ARE NOT the same. Some universal replacements have funny shped ports to cover both applications, but a correct fitting one is better.

CPeter

 

[buickanddeere]

How did you squeeze 35HP from a 25HP M/40 engine? That's 140% of the factory rating.
The larger 440i engine was souped up at the factory and only made 33HP? And that took more displacement, larger ports, larger valves, higher rpms, more compression, larger manifold & a larger carb.

 

[Moose]

Same displacement as 440 now, lots, lots higher compression, etc.