Infraction Hawkeye downs speed run

[Racer X]

I am not sure how to title this thread.

The event is called the Rickey Lee speed run challenge.
But no one knows that. It’s a speed trial sponsored by Crash and Bash hobbies in Cedar Rapids Iowa. The event is held at the 1/4 mile asphalt speedway across the street called Hawkeye downs.

Basically it’s a big race track we get to use for speed trials. The track is great but not a straight line. It’s an oval.

No rules just run what you brung and go fast.
The game is to come off the turn as fast as possible, accelerate as fast as you dare then if you want to run again turn left.

The guy that holds the record has a limitless that can get 160 in a straight line but the top speed is 130.

So my plan…
And let me emphasize I am an experienced racer. My plan is to get to the starting line. After that all plans are tossed in the trash.
But my plan is to build a twin motor infraction capable of 16s batteries.

I think I need weight for traction and use two motors for the acceleration and braking.
The set up will be based on my oval racing experience and turning left.

I am not even going to worry with the speed part. I am going to focus on the big curve. Speed will come if I have the control.

Rickey Lee speed run challenge

 

[parcou]

Damn...nice, but for speed runs, I'd never run my Infraction 6S on that cracked surface. I even bash on smooth surfaces only. It takes the lights to bump at that speed to pop the nose up, and she is in flight! Speed runs you want the nose low and good down draft in the rear...but watch out for cracks, LOL

Yet it is still a cool place to run Thanks for sharing

 

[Tex Koder]

I am not sure how to title this thread.

The event is called the Rickey Lee speed run challenge.
But no one knows that. It’s a speed trial sponsored by Crash and Bash hobbies in Cedar Rapids Iowa. The event is held at the 1/4 mile asphalt speedway across the street called Hawkeye downs.

Basically it’s a big race track we get to use for speed trials. The track is great but not a straight line. It’s an oval.

No rules just run what you brung and go fast.
The game is to come off the turn as fast as possible, accelerate as fast as you dare then if you want to run again turn left.

The guy that holds the record has a limitless that can get 160 in a straight line but the top speed is 130.

So my plan…
And let me emphasize I am an experienced racer. My plan is to get to the starting line. After that all plans are tossed in the trash.
But my plan is to build a twin motor infraction capable of 16s batteries.

I think I need weight for traction and use two motors for the acceleration and braking.
The set up will be based on my oval racing experience and turning left.

I am not even going to worry with the speed part. I am going to focus on the big curve. Speed will come if I have the control.

Rickey Lee speed run challenge

Nice event and cool that the hobby shop has access to a facility like that!!


But I'd imagine the centrifugal forces generated during the turn will be intense on the suspension and wheels/tires though..

 

[joshludden]

I am not sure how to title this thread.

The event is called the Rickey Lee speed run challenge.
But no one knows that. It’s a speed trial sponsored by Crash and Bash hobbies in Cedar Rapids Iowa. The event is held at the 1/4 mile asphalt speedway across the street called Hawkeye downs.

Basically it’s a big race track we get to use for speed trials. The track is great but not a straight line. It’s an oval.

No rules just run what you brung and go fast.
The game is to come off the turn as fast as possible, accelerate as fast as you dare then if you want to run again turn left.

The guy that holds the record has a limitless that can get 160 in a straight line but the top speed is 130.

So my plan…
And let me emphasize I am an experienced racer. My plan is to get to the starting line. After that all plans are tossed in the trash.
But my plan is to build a twin motor infraction capable of 16s batteries.

I think I need weight for traction and use two motors for the acceleration and braking.
The set up will be based on my oval racing experience and turning left.

I am not even going to worry with the speed part. I am going to focus on the big curve. Speed will come if I have the control.

Rickey Lee speed run challenge

Where are located? I'm pretty close, in North Liberty. I'd love to get together sometime & just talk, drive cars.

 

[Racer X]

Damn...nice, but for speed runs, I'd never run my Infraction 6S on that cracked surface. I even bash on smooth surfaces only. It takes the lights to bump at that speed to pop the nose up, and she is in flight! Speed runs you want the nose low and good down draft in the rear...but watch out for cracks, LOL

Yet it is still a cool place to run Thanks for sharing

That’s what makes this challenge special. It not about going fast. It’s about going faster than everyone else and not taking it home is a bag.

Going to be fun the rest of the year I’ll I’ll be racing my speed rig and my 6 s plus a GT and A short corse truck on a regular rc oval track called Storm Steal.

Don’t hate me but I also have access to this track .

 

[Dan B.]

Just to clarify, I’m assuming that you’re going twin motor, both on 8s, and not running 16s voltage? 16s voltage seems counterintuitive on a 1/4 mile oval, not to mention cramming two 16s capable ESC’s in an Arrma Infraction.

 

[Racer X]

Where are located? I'm pretty close, in North Liberty. I'd love to get together sometime & just talk, drive cars.

In Cedar Rapids . You can find them on Facebook.
They have an awesome indoor race program and a big crawler corse.

Crash and Bash hobbies
4601 Sixth St SW
Unit B
Cedar Rapids, IA 52404
United States

Just to clarify, I’m assuming that you’re going twin motor, both on 8s, and not running 16s voltage? 16s voltage seems counterintuitive on a 1/4 mile oval, not to mention cramming two 16s capable ESC’s in an Arrma Infraction.

Yes two complete systems on 8s
Probably use castle 1721-2400 combos because I really like the data logging castle uses.
Not sure about the capacitor. This is not a dragster and punching the throttle is a bad idea for traction.

 

[joshludden]

In Cedar Rapids . You can find them on Facebook.
They have an awesome indoor race program and a big crawler corse.

Crash and Bash hobbies
4601 Sixth St SW
Unit B
Cedar Rapids, IA 52404
United States


Yes two complete systems on 8s
Probably use castle 1721-2400 combos because I really like the data logging castle uses.
Not sure about the capacitor. This is not a dragster and punching the throttle is a bad idea for traction.

I've been there a couple times, I have just been getting back into the game.

 

[Dan B.]

In Cedar Rapids . You can find them on Facebook.
They have an awesome indoor race program and a big crawler corse.

Crash and Bash hobbies
4601 Sixth St SW
Unit B
Cedar Rapids, IA 52404
United States


Yes two complete systems on 8s
Probably use castle 1721-2400 combos because I really like the data logging castle uses.
Not sure about the capacitor. This is not a dragster and punching the throttle is a bad idea for traction.

External capacitors aren’t necessary if you’re running XLX2 ESC’s. If using MMX8s ESC’s each will need its own cap pack if speed running. Maybe not for you if you’re limiting your runs to that short stretch, as ripple wouldn’t really be much of a limiting factor at that point. You will already be so overpowered for that limited stretch anyway, even if the ESC’s started limiting it probably wouldn’t make much of a difference. With a dual motor 8s setup I doubt you’d even hit 1/3 throttle.

 

[Racer X]

External capacitors aren’t necessary if you’re running XLX2 ESC’s. If using MMX8s ESC’s each will need its own cap pack if speed running. Maybe not for you if you’re limiting your runs to that short stretch, as ripple wouldn’t really be much of a limiting factor at that point. You will already be so overpowered for that limited stretch anyway, even if the ESC’s started limiting it probably wouldn’t make much of a difference. With a dual motor 8s setup I doubt you’d even hit 1/3 throttle.

Thanks
I would rather not use capacitors . Just for simplicity.
I know this is going to be totally over powered. I the torque will help with the short track. Traction being the next issue.

I’m going to build it 16s capable but will use two 6s packs at first.
From my experience with land speed racing on two mile airport runways I think it’s best to start slow with 12s and 30-50 throttle then slowly up the power. It is not only fighting the track but the weather.

I plan to use a Delta plastics body it has good down force at the front. And the rear has good vertical stabilizers that are sold separately for repairs.

I got the dual motor mount. Waiting for the roller to begin building.

 

[Dan B.]

Good luck with the build! What ESC’s will you be using?

I’m going to build it 16s capable but will use two 6s packs at first…. I think it’s best to start slow with 12s .

Just to be clear and to avoid confusion if you ask a question later, or for others trying to understand your setup, you will not be running 16s or 12s. You will be running 8s or 6s. You can’t stack voltage numbers to get a total from separate ESC voltage inputs. It needs to be stated as the actual voltage you are running with each ESC/motor combo in the build. Two 8s setups do not equal 16s, much the way that two 6s LiPo’s wired in parallel do not equal 12s.

 

[Racer X]

Thanks. I appreciate that. I hate to be confusing
I am new at anything past 3s and never used more than one battery pack.
Its dual 6s at first one battery and ESC per motor. And one motor will be running in reverse.

I plan to use the castle 1721-2400 kv motor and it is a sensor motor.

Not sure about running one backwards. I can swap two of the wires. But does that affect timing?
Do the motors sync up?

 

[Dan B.]

If you’re running a Castle sensored setup you can NOT reverse motor wires to change the direction. The ESC’s would be irreparably damaged. You have to go into the ESC programming menus (with CastleLink) to change the direction. The timing would not be altered from that, but in all other respects the ESC’s should be setup the same as one another in regard to timing, LVC, punch, etc. The ESC’s/motors do not synchronize with one another, as you will be running two separate stand-alone systems and that’s why the ESC settings have to be the same.
You mentioned the 1721 Castle combos, but will you be running XLX2’s or MMX8s ESC’s?

 

[Racer X]

thank you very much for that information.
I was thinking I needed the ESC to be exactly the same direction and all. Changing with castle link is the easy way.

I was planning on running XLX2. But what would you suggest

 

[Dan B.]

I think most would say that the XLX2’s are the best choice for speed applications of any other ESC available.

 

[Racer X]

I got the second roller. It’s actually in great shape.
I got it all torn down. Thank you Earl Morehead for the warning about the lock tight in the motor mount.
Definitely need heat to get those screws out.
So now I need to clean everything up and start getting the speed car ready to roll.

Thinking about the carbon fiber chassis. Maybe I can mount the batteries on the left side to help with the corner.

don’t want to spend 190 bucks every time it tumbles.

 

[Racer X]

I got everything taken apart and now I need to rebuild. I think the chassis plate is bent. I mounted the front dual motor mount but the rear would not line up as I expected. I reamed the holes slightly and it all bolts in . But I am going to get a flat carbon chassis.
It will give me more room to work with.

In the mean time I am working on the drive line.
I plan to use a center spool. Any suggestions on oil weight for the differentials?

 

[Racer X]

This is the chassis I ordered. I can mount both batteries on the left side somehow. Maybe side by side or in line. and the ESC’s on the right. I am also going to have to relocate the steering servo and this should make that a bit easier.

 

[Dan B.]

This is the chassis I ordered. I can mount both batteries on the left side somehow. Maybe side by side or in line. and the ESC’s on the right. I am also going to have to relocate the steering servo and this should make that a bit easier.

View attachment 357571

Before you make your final decisions on placement, I would recommend getting it built into a roller, throw on the wheels, and play with electronics and battery positions to provide the best balance. You don’t want 2-4 heavy bricks in a concentrated area. You have a lot of real estate to exploit there.

 

[Racer X]

Before you make your final decisions on placement, I would recommend getting it built into a roller, throw on the wheels, and play with electronics and battery positions to provide the best balance. You don’t want 2-4 heavy bricks in a concentrated area. You have a lot of real estate to exploit there.

Definitely the plan.
That is why I went with this chassis. I spend a LOT of time with corner weight scales. I race 1/10 scale pan cars on carpet and they are very sensitive to balance. I am approaching this as a giant oval car. The idea of coming around the corner at close to 100 mph and accelerating past 130 is thrilling.