.67 goldhead cmb 2 glow plugs information

[Chad hebert]

Can someone point me in the right direction to anyone with info. On a .67 2 glow plug gold head cmb engine?

 

[Danny King]

Can someone point me in the right direction to anyone with info. On a .67 2 glow plug gold head cmb engine?

What do you want know.

 

[Chad hebert]

What do you want know.

Where can I get parts,and how competitive would it be with today's engine's.

 

[timothy johnson]

Its unlikely that parts are available from CMB. There are people that still have the older engines along with parts that you will see on IA once and awhile. Since the introduction of the Greenhead CMB 67 there have been many improvements like timming, head buttons and large carbs. There are many people on IA that have modified the older motors to run really well, however why do that when the Green, Blue and latest 67 engines are such great motors.

 

[Danny King]

Where can I get parts,and how competitive would it be with today's engine's.

Parts will be hard to find. Performance stock vs a stock current motor really needs any a comparison.
You would be better off keeping an eye out for a greenhead or blue head used.

 

[Roxyflash]

Those old disk motors in the right hands can scream and will run with the pack.Woods rc use to modify them square bore the carb and rework the disk clearance and timing.I remember when tidewater was blowing them out the door for 175.00 those were the days!

 

[john v]

I bought a few of these gold heads from sandy at tidewater.
I think they were 175$
Sandy was awesome, she knew motors

 

[Buckshot]

Where can I get parts,and how competitive would it be with today's engine's.

As the guys above have pointed out, parts are sparse. But since you have it, I’d say run it until it pukes or you find/buy a new bullet. Just because it’s old doesn’t mean you can’t have fun with it!

 

[Timbo Whalen]

Where can I get parts,and how competitive would it be with today's engine's.

Check with Alan Elzer....seems he bought all of Stu's NOS parts for that series CMB engines.

We had a new one we sold, with NOS spare parts, but converted to single plug setup, and installed a 45 RS EVO backplate with Speedmaster carb.

And, yes, with some mods they can be quite competitive.

 

[Wasted wages]

They’ll run… trust me.. just takes a little finesse.
Hell, I still love my old OPS motors, at least I can still make them scream…

Never really saw the advantage of a dual plug head, other that burning up twice as many glow plugs…or blowing V notch’s thru the tops of pistons..
and I’ve done duals, triples and quads.. in a twin it looked like a damn glow plug caddy…

 

[Wasted wages]

Check with Alan Elzer....seems he bought all of Stu's NOS parts for that series CMB engines.

We had a new one we sold, with NOS spare parts, but converted to single plug setup, and installed a 45 RS EVO backplate with Speedmaster carb.

And, yes, with some mods they can be quite competitive.

View attachment 327887
View attachment 327888

That thing is clean!!!
Very nice Timbo !

 

[Timbo Whalen]

That thing is clean!!!
Very nice Timbo !

Thank you, Frank.

 

[steve wood]

Best 67 motor ever made.master the disassembly,fix the rotor clearance,square the carb bore,lose the twin plug head,set timing,and free up wrist pin clearance(if you don’t do this you can lock it up))

 

[Timbo Whalen]

Best 67 motor ever made.master the disassembly,fix the rotor clearance,square the carb bore,lose the twin plug head,set timing,and free up wrist pin clearance(if you don’t do this you can lock it up))

Look familiar?

 

[steve wood]

Now I’d raise the exhaust to 190.zoom,zoom

 

[Timbo Whalen]

Now I’d raise the exhaust to 190.zoom,zoom

Those engines with roller bearings need more castor in fuel, IMO.

The hobby misses you, Steve....your workmanship is top shelf, without doubt.

 

[Wasted wages]

I’d T slot the intakes, bore holes in the piston to match, and skirt the piston, set the exhaust to 191…

But that’s just me…

 

[Timbo Whalen]

I’d T slot the intakes, bore holes in the piston to match, and skirt the piston, set the exhaust to 191…

But that’s just me…

After the T-porting era, we found that slotting and window porting the piston closest to the boost port worked best. It's possible to also window port the boost port in like fashion, but we couldn't see a noticeable change in on the pond performance. Maybe different on a decent dyno, who knows. This is a NR67 flow configuration that works really well. Didn't grind new timing figures into it, but a .010" lift (shim) under sleeve flange woke things up....had to take .010" off the deck on the sleeve to compensate, too. I guess a .010" cut on the button touch down surface would've maybe been a better way to go. Buttons are cheap, compared to new sleeve + labor time.

Eventually, we're going to apply the same thought to our CMB 67's and 80's.....we'll keep you posted, Frank.

 

[Wasted wages]

Had a guy in our club that loved K&B .67’s and .82’s..
He would machine all sorts of billet housings, different bearings, throw a RPM rod in them and could make them live…

He took one and set the timings, ported the sleeve, and then set the head clearance at 0, and put a .002 shim in it. His thinking was that between the rod slack and the shim the piston would never touch the head button at max RPM as oil would fill the void in the squish band and completely seal the chamber at TDC..
It actually worked! There was never any evidence of the piston striking the button and it made the most perfect burn pattern on the head of the piston with a perfect circle of “clean” around the outside of the piston crown.
Yeah, he hammered out a few glow plugs until he got the volume right, but man he could make those old motors scream !!

 

[Wasted wages]

After the T-porting era, we found that slotting and window porting the piston closest to the boost port worked best. It's possible to also window port the boost port in like fashion, but we couldn't see a noticeable change in on the pond performance. Maybe different on a decent dyno, who knows. This is a NR67 flow configuration that works really well. Didn't grind new timing figures into it, but a .010" lift (shim) under sleeve flange woke things up....had to take .010" off the deck on the sleeve to compensate, too. I guess a .010" cut on the button touch down surface would've maybe been a better way to go. Buttons are cheap, compared to new sleeve + labor time.

Eventually, we're going to apply the same thought to our CMB 67's and 80's.....we'll keep you posted, Frank.

View attachment 328159

Nice work BTW… looks clean!
I really like the finger porting CMB did on the exhaust ports,, cleaning those up and the exhaust port in the case can work wonders in these motors..