MC2 - the most powerful bushing engine ever built !!!

[Jeff Campbell]

$69 would buy a new one when they were introduced in 1962. The MC2 was a fixed head engine, with a large half gold ball combustion chamber (low compression). This was a 100cc engine, same bore and stroke as the MC7 that was introduced at the same time. It has 3 transfer ports on each side of the cylinder, 3 exhaust ports, but NO 3rd port or boost ports. At first glance you would think it was a MC49, but it packs much more punch!

Only a short production run of a few months, Feb 1962 to April 1962. I believe the bushing class died out in 1962.

I just finished restoring this MC2, with a few changes: needle bearing instead of the lower connecting rod bushing, a MC40 manifold (GoPower 6 petal cage), and a tillotson carb.

It returned to the race track yesterday, screaming out some good laps at the East Lansing kart track ... great sound and fun!

Jeff

[ted johnson]

Jeff: So why did you delete the conrod bushing? Charlie Craibe worked at Wyatt Enterprises kart shop in Cocoa, FL. The owner of Wyatt's, Howard Wyatt, had a fully modified Mac 2 on his Fox. It was as fast as many Mc-7's and AH-58's, and ran reliably all season. Howard had owned the bushing class at our local track in Rockledge, FL, with his full open 5-port 580B Bender bushing, but the Mc-2 was in a league of its own. It was definitely the fastest bushing in the Southeast. Fun days! Your Mac 2 looks great-hope you bring it to TBO! TJ

[Jeff Campbell]

Ted - simple answer: I didn't have the bushing or rod (assuming it was a special rod too?), those parts were replaced by someone else unfortunately. I did think about adding boast ports, which would be easy since the 3rd port pocket is still there, I could have done the MC90 style boost ports, but decided it just wasn't right to be hacking away at a almost stock standard bore MC2 block. It makes perfect sense the Howard Wyatt could get a lot of power out of an MC2, I think by lifting and squaring the exhaust ports, adding the boost ports and doing some creative welding to reduce the block combustion chamber size ... it should be more potent than a stock MC7-9 or even early MC90-91 series motor.

Jeff

[ted johnson]

Hi, Jeff. I'm not sure the rod was anything other than an Mc-7 rod with a full floating bushing. Anyhow, it was a pleasure watching that feller whom we considered an "old man" dominate both the 580 needle bearing and the bushing classes. Wyatt Enterprises was a major force in Florida karting then. Dick Wyatt, Howard's son, had a 4-wheel brake Dart with twin S&S Oil (Dick Collier) 820's on it, and he and I fought tooth and toenail in the dual open class for a while. Both Wyatts could drive! I ran a GK 1200 with triple Macs for a while before giving up C class and going back to my beloved A Super. Hope to see the Mc-2! TJ

[Chris Marchand]

We ran a Mc 2 in 1962 and it blew away all the other bushing engines. A year or so later we took all the guts out of the Mc 2 and put them in a Mc 7 block, it ran great also. Wished we saved all that stuff !

[Glen Annarumma]

Hi Jeff I also have an MC 2 that is in mint condition but did away with the bushing connecting rod. Bill Hermstead did some innovating and put an 91 rod in it. He needed to open up the piston at the wrist pin area so the rod would fit. Man let me tell you it runs great and I know it,s stronger than the bushing rod. I was told it is a very rare engine. I also have a Hovey manifold on it.

[Brian Thomas]

I have some bushing class P.P. stuff and was thinking of doing something with it but ,,,, Well maybe historic class ???
Brian

[steveohara]

Jeff,

I think you have a typo in your initial post where you say it has a Mc40 intake manifold... the 40 had a dual carb manifold as OEM.... the manifold on your motor is a Mc45/75 version that is the same casting as the original Mc 2 manifold with the hole enlarged to accept the Go-Power reed cage. It was only used on the 45/75 and replaced with the REED Sloper on the next set of models 90/100.
Regards,
Steve O'Hara

[Jeff Campbell]

Steve,
Yes, you are correct, my error. It was a MC45/75 manifold with 6 petal Go-Power pyramid reed cage that I put on my MC2.

As for those early type Mac manifolds, the Super motors used a type that has a boss with threaded hole for attaching the head shroud ... the standard motor manifold on the earlier motors does not have this boss. So the MC45/75 manifold on my MC2, does not look exactly like the one that came on the motor.


Glen,
Your MC2 looks neat, not many around for sure. I ran mine at TBO this year, but with a Mac flatback carb, it ran really well.

Jeff

[steveohara]

Jeff, Glen,

I'm gathering the parts to build a Mac 2 and have a couple questions. Does the Mac 2 crank have the large key slots like a 6 ?
What about the flywheel.... is it like the version on the 6 and 7?
About the piston and rings... did the motor use the thick rings like the Mac 10 or the thin steel rings?

Thanks for any help you guys can offer.
Steve O'Hara