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Tony Condon
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Hi
Most pitmanns are big strong old motors ,and I am sure they would run at more than 12 volts ,and i do'nt suppose 13- 14 volts would do too much damage ,although i would imagine that they may get a bit warm at 20 volts ,especially if you have loads of amps
may be ok for a bit of drag racing at those sort of volts where the motor is only running for a few seconds
But .silly question ,why dont you run them at 12-13 volts like everyone else does ,and what they were designed for ?

Cheers tony
 

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Hi, I usually race many 1/32 old Revell cars equipped with RP66 and also an Autohobbies Cobra with a DC198B, geared between 1/3 and 1/4. They run cool and powerful at nominal 12V (real maybe a bit more). I use old Scalextric power packs with a modern silicon rectifier instead of the original selenium and a 1000 microfarads capacitor between the output terminals, one power pack per lane. More important than voltage is to ensure that your power source is able to give enough current, to be sure a minimum of 1.5 Amperes per lane, as these motors need much more current than the modern ones. They are fun to race in twisted circuits, enjoy them!

Eduardo
 

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You're right, the old drag racing rules had cars running at anywhere from 12 to 36 volts, according to the class entered, usually in 6 volt increments.

The motors would generally be okay for the second or so it took but they were definitely prepared at the higher voltages, namely epoxying the windings, probably balancing, etc. Also, these were almost exclusively the big "padlock" style motors, the Pittman DC85 and Ram DC850 or 857, which were very rugged units.

A couple motors were also wound for 18 volts, especially the Kemtron units, which were also padlock style (actually, more technically, laminated pole), and came 4 to 18 volt versions.

In the early years, Figure 8 racing was also very popular, and these were generally run at 18 volts, with this style motor.

I would guess most of your motors would be okay up to 18 volts, but I wouldn't try running them in an endurance race!

Don
 

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Hey all,
I've a bunch of Kemtron X503 motors, 6 Volts through 10 Volt - The 6 and 8V are wonderful motors on 12V, smooth and torquey with a similar max rpm to a good 36d but with better brakes. Those marked as 10V are useless running at 12 though, just not that fast and have no appreciable range - I suspect these would run much better at a higher voltage.

Don, you've whetted my appetite with the possibility of the Kemtron 4 volt - Is it the same as the skinny 6V unit or same dimensions as the 503 ?

Cheers,
Simon.
 

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Eduardo care,
the engine RP-66 (Revell-Pittman ... or engine manufactured by Pittman exclusively for Revell) is intended to 1:24 Revell units.

The units intended to 1:32 are the RP-77 !

Revell-Pittman motors could be purchased separately.
Never part of RTR-box, RTR-circuits or motorkits.

They are the engines recommended articles in the first slot of Revell, the bodykits, 1963 for the first 2 Chevy E'62 Corvette'63 and type Jaguar.

Look at the following leaflet mounting instruction bodykit, motor section:

 

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QUOTE (gluebomber @ 2 May 2012, 04:44) <{POST_SNAPBACK}>Don, you've whetted my appetite with the possibility of the Kemtron 4 volt - Is it the same as the skinny 6V unit or same dimensions as the 503 ?

Cheers,
Simon.

In fact Simon, now that I think of it, the 4V version were I think sold under the KTM label - pretty much the same exact thing as Kemtron but with KTM stamped on the frame, different boxes, etc.

They do come up now and then on ebay, so keep your eyes peeled!

Don
 

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QUOTE Eduardo care,
the engine RP-66 (Revell-Pittman ... or engine manufactured by Pittman exclusively for Revell) is intended to 1:24 Revell units.

The units intended to 1:32 are the RP-77 !
Sorry, that information is backwards.

RP66 = 1/32 scale (small motor)

RP77 = 1/24 scale (larger motor).

Although, both motors can be used in either scale (and, I do this all the time), the RP 66 is smaller than the RP 77, which, makes it more suited to the smaller scale.
 

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Yes, looks like it. Proof reader wasn't doing his job.

I have an RP77 in a 1/32 Revell 250 GTO, and, trust me, it is a tight squeeze. The bottom of the interior tray had to be ground thin where the armature rubs on it, and, the brush spring is way too close to the chassis side rail for comfort. I keep a small piece of electrical tape there to stop shorting.

It's a big motor for 1/32 scale.
 

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I was trying to use a motor which I believe is the RP77 after comparing it to photos, and like you say , it is a tight squeeze in the 1/32 Revell chassis, with the brush springs interfering with the chassis, and it seems impossible for me to fit this one in the 1/24 Revell chassis such as the Grand Prix Lotus Ford with either the front frame section inside or outside of the rear section. Seems they made these chassis both ways. Has anyone got a photo of this chassis (1/24) fitted with the RP77 or any suggestions. I have fitted a RP66 to the 1/24 chassis with no problem.
 

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QUOTE (bwaminispeed @ 2 May 2012, 21:38) <{POST_SNAPBACK}>Sorry, that information is backwards.

RP66 = 1/32 scale (small motor)

RP77 = 1/24 scale (larger motor).

Although, both motors can be used in either scale (and, I do this all the time), the RP 66 is smaller than the RP 77, which, makes it more suited to the smaller scale.

I am still waiting for anyone to clear up this confusion and in the meantime I went back to Jose's Revell Flyer and under Racing Motors it states that the RP77 was for the 1/32 chassis and the RP66 was for the 1/24 chassis.
Here someone suggested this is backwards , however upon close inspection, this is what I have concluded; RP66 is the smaller motor (Pittman DC66) and will fit in either scale Revell aluminum chassis,
RP77 (Pittman DC77) is the larger motor and barely fits the 1/32 chassis due to closeness/interference with the side chassis rail, and does not fit into the typical 1/24 chassis such as Revell Racing Chassis kit R3310-200 . There is a chance that there is a wider Revell Aluminum ladder chassis for the F1 cars , has anyone got a photo showing the RP77 in the 1/24 chassis or is it true , as the flyer clearly states , the RP77 was meant for the wider 1/32 chassis .
 

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What does it matter, they were off the shelf train motors made by Pittman bought by Revell to go in already produced chassis.

They fit what they fit. Use them where you like, in whatever scale you like, just like we did back then. We weren't the least bit concerned, or, guided by Revell's advertising blurbs.

Just plain common sense would indicate that in general, the larger motor was for larger cars. And, as I stated, while the RP77 does fit the 1/32 scale chassis, the body doesn't fit without modifications.
 
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