I've been running the K&B's continuously for over 30 years. They are wonderful
engines...but I have never yet run one with a K&B carb....always an OS, or now
days with the Magnum carbs. The biggest rub on K&B since the beginning was
the carbs sucked.....the perry's were even worse, but that's just my opinion.

The K&B .61 is the best replacement engine for the weaker .46's, because they
weigh the same, and put out way more power. I always run them on 15% nitro,
an oil blend with 1/3 castor, a K&B 1L plug, and a Master Airscrew 11-7 1/2 prop.

I still have my original 6550 I got in a trade, about '73....it was new, but was
missing the carb....five rebuilds and three crankcases later. I put an OS 7B carb
on it, and never looked back. Most Guys when you mention K&B will turn up their
nose....but I love 'em.

FBD.