Source for engines??

[Bill Gibson]

Im just sharing my own experience...strictly my own opinion....i ran a Mac 67 in a scale hydro and will NEVER do it again......why? Absolutly no low end no matter what i tried.....Its a great rigger motor or maybe a mono motor and is a very well built and dependable engine...but i changed to a Picco 67 EXR with an O.S. 9b carb and i had a COMPLETLY different boat...i think with a CMB 67 Green Head the results would be the same... i have one but havent run it yet, but you will find that alot of guys are very happy with that motor also..if you can find an EXR for a good price, i think youd really like it because whether you get a Mac or a Picco spare parts may be an issue...... or spend the money for the CMB "greenie" if you can, and own an engine that parts are available for.....When Al Hobbs gets His AA 67 motors out, im sure they will be GREAT motors also! Hope you can find something good!

I hear ya Bill! the only reason I'm using the Mac motors in the .67 mono is that is what the boat was set up for. With the cmb the carb is too close to the fuel tank. The Mac I'm running now is a second generation with the large .550" bore carb.( I heard they share the same case with the .84). I bought a back up motor from Don Ferrette that is a first generation that came with a .550 bore and .509 bore throttles. (and smaller case volume). The new Gen 2 is a WILD THING at wide open and will not mill. Perhaps it just needs more run tim to loosen up a bit. I,m taking both motors with me this Sunday.

Glenn

Glenn, ive got 3 Mac 67s, and someday, when ive got the time and MONEY, i hope to build a twin to stick 2 of em in.....they really are good motors...my buddy Tom Foley has been racing a twin with Mac 84s for YEARS and must have a milion hours on the motors and they just keep on runnin....FAST! I mean they seem to never let him down! I run Mac 21s and 45s in my Sport hydros and they have been great, but im sure that you know yourself that when you run a Scale Hydro its awfully nice to have some throttlability instead of an ON/OFF SWITCH! I do love the look of the new AA motors and im sure when i scatter the Mac 45 in my Sport 40, ill get one........

 

[John Knight]

I (and many others too) have found out that the MAC67 engines run better, with easier throttling, with the smaller carb, the .510 vice the larger .550. It just seems to be more responsive, easier to back off and more quick to recover. I have tried both of the carbs and the .510 just meet my needs better. Maybe it is at sea level but I know of many others that prefer the .510 over the .550.

 

[Mike Hughes]

.( I heard they share the same case with the .84). Glenn

Not true. They are the same on the outside. The bore is different. You will not be able to put a 84 PS in a 67 case. The 67 will fit the 84, but will be a little sloppy. New speed secret. NOT

Mike