K&B greenhead torpedo

[John_Craig]

I know of 2 different styles the 3 bolt backplate & the 4 bolt.  I believe the 3 bolt is the older version but what are the approximate  years of production of each?  What is the difference in performance?   Is a three bolt 29 equal to a fox or McCoy 29?

[john e. holliday]

If I remember right, the Greenhead K&B's were favored for racing and combat as they had just a little more power.  My first .35 was a McCoy .35 Redhead, then I managed to save enough to get a K&B Greenhead .35.  Never thought it was going to start as it was tight.  Still have it somewhere.  Remember this is back before crankcase pressure. 

[Dalton Hammett]

Back in the late 50's I was lucky enough to acquire a couple of the GH .35s to go along with the McCoys I was using.  The K&Bs always seemed stronger and somewhat faster then the McCoys to me.  I had one K&B in a T-bird back them that was a real porker and it handled it much better than I did..............

[George]

I know of 2 different styles the 3 bolt backplate & the 4 bolt.  I believe the 3 bolt is the older version but what are the approximate  years of production of each?  What is the difference in performance?   Is a three bolt 29 equal to a fox or McCoy 29?

The oldest three bolt glow K&B's did not have green heads. They made improvements along the way finally including a tapered piston referred to as TCC - Temperature Controlled Clearance. I think the last three bolts included the green head. Then came the four bolts. The switch to the four bolt came in the early/mid fifties.

Comparing them to a McCoy .29 is hard because McCoy's came in various forms, the most powerful being the rear rotary BB .29 red head racing engine. This is way before the front rotary "red heads" most refer to.

You could say they were mostly equivalent because they were all more powerful than previous engines and not as powerful as modern engines. There was a LOT of competition and performance improvements during the fifties, mostly due to speed, combat, and rat racing. At least that's the way I remember it.   

George