GM3

[Nairb]

Dang, my brand new Green Machine 3 is sure an UGLY cuss (definitely the ugliest motor I've owned), but it sure can scream. I can't wait to throw it in my new truck I'll be getting this week.

[The_Ne-Go-She-Ate-r]

I Think it is a very good looking motor. becouse its out the ordinary.
its different, and very green.

[rc10gt_bb]

I think that it devinetly looks awsome. I like the retro look of it.

[doublet]

Those motors really do look funny, but they do awesome in buggies, but I cant seem to make it do better than a p2k in a truck. I think I geared it wrong.......

[Grizzbob]

That's quite possible, doublet. The GM3's do not like to be geared like the P2K does, they're really much happier if you treat them just like the Yok-based motors(like the Reedy Rage), their power band is a lot like the Yoks, & should be geared that way.... http://www.rccaraction.com/ubb/smile.gif

[ovalnator]

Yeah, the GM3 is ugly, but they are ballistic!

[doublet]

You were right Grizz, I had to gear it down from a 20 to a 18t pinion, now it does a lot better..........

[Nairb]

What's the deal? My Lunsford titanium "Fat Boy" motor screws don't seem to mesh correctly with my new GM3. They work great with my old Midnight and Midnight 2, but the threads don't seem to fit as well on my GM3. The screws are very tight going in and the motor looks like it's getting new threads cut. Did they change the thread used in motors? Anybody else notice this in the past couple of years? What's the deal?

[Grizzbob]

No, I haven't noticed anything like that. Maybe yours didn't get its threads cut properly in the first place(just a fluke)....

[Nairb]

You'll never believe this...I hardly can. At my LHS they have a GM3 with some CRAZY dyno numbers. This bad boy goes 38,000 RPMs. SERIOUSLY! I don't know how, but it does. There is a serious drawback, though. It has 1/3 the torque of other GM3s. That is some major variation between motors. Can you believe that? I am NOT making this up.

[Nairb]

I just checked; my GM3 has 152Nmm of torque and the CRAZY-RPM one only has 68Nmm. Pretty weak, huh?

[Grizzbob]

That is pretty crazy, what did it have for power(in Watts)?

[Nairb]

I don't know, I'll check next time I'm in (unless someone buys it first).

So, my motor is off to the distributor now. I only ran the thing ONCE! Everybody I showed it to said that they'd never seen a motor get all burnt inside like that. I hope the replacement doesn't give me trouble.

[TufferWilde]

What is the general feeling for gearing on the GM3? Currently I run P2k's... Stock spur size in my Yok MR-4TCW with a 25t pinion, and 87/20-21 in my FT T3.

Just bought the GM3 last night and so far I am guessing that it will be in the ballpark of the Rage Type R, but I don't remember the Rage's power number that high. If I recall correctly, the GM3 numbers on this one were in the area of, 30,500 RPM, 129.5 W, and 71%Eff.

Any help would be appreciated!

Thanks

[Nairb]

In the instructions for a GM3 it said to go down a tooth or two on your pinion, when compared to a P2K, so I'm gonna go with a 19t in my XXXT (instead of 20). At least I'll try that gear first; I may change from there.

[ovalnator]

Nairb, you running the stock spur in the truck? I had to go to an 18 w/ mine.

[Nairb]

I will be running the stock spur, but as of yet only my reciever is installed. I have to wait for my ESC to come back (by way of UPS) before I can install it or the servo. So I haven't even had the chance to drive it yet. So you use an 18 with the 88 tooth spur? What made you decide to use an 18 instead of 19? Did you need more torque?