different sized carbs?

[dmulhall]

So I'm running a IND 251 in my b2b

I had a 218 and transferred everything over to the 251

not knowing and looking at them, the carbs looked almost identical

but the bigger engine seems to always be starving for fuel in the higher RPM's

the model number on the carbs are

(from 218 that I'm running now) DTF1 6-629

(from 251 that the bigger engine came with) D6K1 6-429

from having them both apart and on the bench, I cant tell a difference in any of the sizing. Bolt pattern is a little different going from carb to throttle body, but other than that I think they are the same. Even have the same rebuild kit part number....

The reason I'm running the carb from the smaller engine is because it was recently rebuilt and was in much better condition. But if the engine is suppose to have the other carb, I can always rebuild that one...

Any help would be appreciated!

Thanks in advance (as always)

[Plymouthy Adams]

did you compare the jet?

[Dodgeb4ya]

Couldn't locate either carb# in my Carter Carburetor master parts books all the way back to the 30's! The jets all have #'s on them. I can look them up for sizing. Also check thottle plate bore, accelerator jet , step up jet size ect.

Bob

[Rusty O'Toole]

Does the throttle bore measure the same? I mean inside the bottom of the carb?

[dmulhall]

I did measure it, and they were both the same

1 9/16" I think? Sound right?

[dmulhall]

When looking at the main jet, which number am I suppose to be looking at?

Both carbs have a 270 along the edge, then a 4 or 5 digit number above it...does that make them 270 jet sizes?

Stupid question, just didn't know if they were part numbers or jet size...??

If so, does 270 sound right for a 251 engine?

[Dave72dt]

That lean gas feeling at higher rpm doesn't always mean it's running out of fuel. It's possible the advance system in or on the distributor isn't working right.