52 replies to this topic

[Pablo]

The Dungeon Raceway has been racing this JK Indy car class for years. Billy wants to slow the cars down and use slower motors. I agree with his decision. The new motor is a strange item. So, here we go - I'm going to document the change on my car from a winner, to, well, we shall see 

 

  

[blue&orange]

You don't mention what the original motor is.   There are low rpm motors from JK and Mid America that would drop right in.   Wonder why the motor you show was chosen.

 

On the plus side, bravo to a track that is willing to slow the cars down.

[CARSHouston]

I'm guessing that you're using a Hawk 7

I hate to say it, but that motor seems too long to fit the chassis, why not just go to a hawk retro that would fit just like the 7.

[Tim Neja]

Or even the new JK Mini Brute?  There are LOT"S of options with the same size motors!! Seems rather silly to jam a much longer motor in there!

[Ramcatlarry]

Mid Am Eagle 25  is a very good choice for womps and smaller tracks as in the JK Hawk 25.  Want to go slower - use the Eagle 18 which is about the same as Scalextric/Carrera 1/32 motors.

[W. J. Dougherty]

We race that Indy chassis with the PS FK motor. We do 40 minutes and near 600 laps races. The motors and chassis stand up extremely well with hardly ever a failure in chassis or motor...

[Rob Voska]

Or even the new JK Mini Brute?

I tested a mini brute and a JK MB in a 1/32 JK chassis.  Both ran identical lap times but sensitivity was from one extreme to the other.  

[Pablo]

The answer to your questions are:

 

-old motor was Hawk 7

 

-track owner made the decision, not me

 

http://slotblog.net/...-prattville-al/

 

I concur with his decision to slow the cars down (since everybody except a few of us were launching in the straights) but I wasn't part of the new motor selection. I agree the motor is too long but if it wasn't a challenge, I wouldn't be posting this thread.

 

My job is to follow the rules and continue to win races, At least, that's my goal. The motor to be removed has won more than it's share, but the brushes and brakes are almost finished anyway 

[Ramcatlarry]

That GTP body is a strange looking indy car.

If the lead wires do not interfere with the body after it is mounted, check the center of gravity in all four directions.  You may want to add  bit to the left side to neutralize the mass of the motor.

[airhead]

Back 14 years ago when we started racing the JK Indy car with the Indy body, the car came with a falcon 4 then 5 then 7 with more speed came more wrecks. So we tried a lot of different JK bodies, then we went to the Mini brute motors, this made the racing fun again, then the racers found a way to change the arm with a hawk-7 arm, some even made tools to do the job.

 

Most of the tech time was spent looking for motor cheating, so we said go ahead and run hawk-7 motors, next I made a higher down force body to keep the cars from taking flight. This helped but with the older track and dips there were more wrecks. I like a good wreck as much as the next guy but it makes for a long race.

 

The new mini brute motors look a lot like the hawk-7. If we use the new mini brute the old armature swap problem may come back.

 

I tried several different motors before settling on this one. Its larger, heaver and slower and a hawk arm won't fit.

 

Before the JK Indy cars with the high down force body were running in the 4.9s now the cars are in the 5.5s on a good lap. Maybe the racing will be close again like it was 10 years ago.

 

Look at Pablo's body, does it look familiar? It's an open wheel Bentlee, Yes! there is such a thing.

[Rotorranch]

I got mine in!

 

Rotor

 

 

 

 

 

[bluecars]

Billy; When you say the racers were changing arms. Don't you mean mainly one racer? You make it sound like everyone was doing it.

[Pablo]

I didn't know that, it's news to me. Maybe it happened before I started racing there?

[airhead]

This is how the new motor, we call ( Hemi 500 ) looks mounted in the old JK Indy and the new JK Indy chassis along with some pictures of the bodies we are using now,   The pink body at the bottom is a body we used a few years back.

 It is a remake of the 60s Banshee that has been altered to fit the JK Indy car chassis. This body had good down force,  and with the slower Hemi motor we may go back to it in the future.

 

The hemi motor has ball bearings on the drive end and only coast $5.00 , but it is only legal to race at the Dungeon and only in the JK Indy class

 

 

 

 

[Rotorranch]

I sure wish Billy would show me how he got his to fit to the motor mount! I couldn't get anywhere close to mount.

 

Rotor

[Eddie Fleming]

Jeff

 

Turn the spur gear around.

[Rotorranch]

I tried that. It didn't work for me. 

 

Rotor

[Eddie Fleming]

Cut the motor bracket off and move it 

 

No don't do that !

[MSwiss]

Jeff,
Run the biggest, full width spur, teeth to the outside, that will clear, and find out what size pinion Billy has on his car.

[Ramcatlarry]

Time to take the cheaters to the woodshed for some LEARNIN'.....

[MG Brown]

For starters, if you want to slow the cars down, go with an Indy Dallara body. That GTP body in the first post is going to create a lot of downforce.

[Pablo]

Cut the motor bracket off and move it 

Not legal at The Dungeon in that class. If it was, mine would have been sliced off long ago

[airhead]

   This gear ratio might sound strange to most, but we are running 12 volts and 30 amps, not the 13.8v 75 amp of the commercial tracks, we turned the voltage down to reduce speed and reduce wrecks so the  fast guys found ways to still get some speed by using taller gear ratios.

 

The gear ratio I found best so far for the Hemi is 15/34 with .730 tires, and NO! the motor doesn't heat up, and braking is good,

 

The longer motor fits OK in the JK chassis, no chassis alteration are necessary or allowed , the chassis must stay as a ready to run except for motor, gears and rear tires , You should be able to buy a JK Indy, change the motor and gears of your choice and be competitive , The body we use are a free one time hand out. extra bodies are $ 3.00 

The body clip holes and wheel well cut out are marked for you, Just trim and mount.

 

Every one is invited, Even Cheater (Greg Wells)!  so come give this class racing a try when we get paroled form the virus .

[Ramcatlarry]

Any long stack C can arm fits in those FK180 motors.  Cheating never stops until the cheaters stop.

 

FYI - that motor looks just like a MidAm "ET" drag motor.

[Matt Sheldon]

They look more like flexi thingies