1275 replies to this topic

[Pablo]

Thanks.

Boy howdy that's tall gears for a hot 24 arm !!!

[Jairus]

I thought it might be okay considering the weight is light. The ratio should be just fine on a King track, but now thinking about swapping in a 7t pinion for further testing on this track. But then that's what testing is all about.
Just wish the track was closer since it costs about $15 in gas each time I make the trip.

[Pablo]

Maybe the wagon needs a gear ratio change as well
Sorry for drift, I can't help myself

[havlicek]

Flat out speed vs driveability. I think a #26 might do well Jairus as I've done a bunch of different arms as tests and the range seems to be between #26 and #28 singles and #28 (on the hot end) to #30 or even 31 doublewinds. Barney has some PDC ("pretty danged cool") plans for Team Cort, but he 'splained to me that he'd hunt me down and shoot me like a dog if I divulged, so... Anyway, I think there will still be some #24 and #25 singles in these light beasts. That should make for some "interesting" racing!

-john

[RichKraft]

John I appreciate the winds advice you are sharing.
I know little about what winds work well on which track and car type, so this is a great help.

Jairus, what is the name of that body?
I love the Hoola dancer in the grass skirt on the dash of your sweet old Ford.

[One27ray]

Very useful info Jairus, the car looks great sitting there. Wow ! it's going to be hard to pick a body Been working on a newer version #8,( closer to the original one) but, this body your using really looks good. Not to mention a few X-project Choti-noda out there too

[chief32s]

OK Guys, not being a racer of either slots nor 1:1s I'm always a bit confused about gear ratios.

Blacklight is running an 8t pinion with a 32t crown (at least as far as I remember). So thats a 1:4 gear ratio.
Jairus has tested his new car with an 8t pinion with a 28t crown, but Paul thinks that's "Tall" for a hot arm and so J is considering a 7t pinion with the 28t crown, again a gear ratio of 1:4

I understand ratios affect top speed and acceleration, but don't get all the terms used.

So if someone could explain in simple terms what tall, short and long mean and what the characteristics are for both, why/how arm hotness affect this, what the different characteristics are of the two 1:4 ratios mentioned above, if any.... Oh, and give me the perfect combination for two balls-out races on a King tracks (hehe). Then I'd be most grateful.

I'm sure I did this stuff in physics years ago, but as I say, that was years ago.

Al.

PS. Thanks for sharing that information Jairus, very useful for everyone involved, but particularly for the likes of me.

[HarV Wallbanger III]

" Do you want me to run your car again and report back?"

No, just was wondering if you had checked all of them and if any other problems cropped up is all. I had thought you had said you were going to do that before you ran your new car and had not seen any report back on them till your post yesterday on running your Balls 'O Fire Thingie...... take a breath and relax Jairus.....

[Jairus]

Thank you John.

Rich, the body is a #15 in Choti's list and they didn't name them. Ray (O2R) Fellows of Raynoda body works did the pull.

[Jairus]

Barney, I made a report (Post #847) on Saturday that the cars are at the track. Plus, yesterday I delivered a 3 ring binder for people to read all about the race, the people and the entries involved. Everything is there including all the past 9 races. I even wrote up a press release for any news organizations and made 20 copies for distribution to anyone who is interested. Glenn says that we have plenty of drivers who want to take part so we might have to rotate them.

OK Guys, not being a racer of either slots nor 1:1s I'm always a bit confused about gear ratios.

Blacklight is running an 8t pinion with a 32t crown (at least as far as I remember). So thats a 1:4 gear ratio.
Jairus has tested his new car with an 8t pinion with a 28t crown, but Paul thinks that's "Tall" for a hot arm and so J is considering a 7t pinion with the 28t crown, again a gear ratio of 1:4

I understand ratios affect top speed and acceleration, but don't get all the terms used.

So if someone could explain in simple terms what tall, short and long mean and what the characteristics are for both, why/how arm hotness affect this, what the different characteristics are of the two 1:4 ratios mentioned above, if any.... Oh, and give me the perfect combination for two balls-out races on a King tracks (hehe). Then I'd be most grateful.

I'm sure I did this stuff in physics years ago, but as I say, that was years ago.

Al.

PS. Thanks for sharing that information Jairus, very useful for everyone involved, but particularly for the likes of me.

Tall or High 3:1 or 3.5:1 means the motor is turning over fewer RPM's to move the car forward one tire rotation.
A low ratio increases 4/1 or 4.5/1 means more RPM's to move the car forward which is easier on the motor.

A tall gear ratio means higher top speed but might not be as quick off the line. A low gear ratio provides quicker starts out of the turn but top speed might suffer. Nobody wants their car screaming at top speed all the way around the track because there are also turns to consider. So we look for a compromise between the two

I am building my car for a King track. The race is won or lost on that long drag strip down to the banked turn. That is why I went with such a high gear ratio and put in a #24s to give it the horsepower to provide the torque. As it was plenty quick out of the turns. In fact, I think I found the perfect ratio for this arm on a King track, but... it's un-drivable on my track. Way too quick and can't seem to stretch it's legs. (Plus, the motor did get pretty warm so maybe it's working too hard?)
Might go back to that ratio before mailing into the first race, but for now I want to experiment with handling. That means making the car more drivable, example: lower the ratio to 4/1 and installing a #26s wind arm along with a few other... modifications to the chassis.

[RichKraft]

Thank you John.

Rich, the body is a #15 in Choti's list and they didn't name them. Ray (O2R) Fellows of Raynoda body works did the pull.

Thanks, I'll have Ray send me a couple, it looks like a great choice.

[chief32s]

Thanks for that explanation J. It is something that I already know, but always end up getting myself confused with. My physics teacher told me that I was numerically dyslexic so no suprise there then.

Just one further question to anyone that wants to chip in...

What is the difference between a 4:1 (28t:7t) and a 4:1 (32t:8t) arrangement, or is there no discernable difference?

Al.

[Jairus]

Nothing regarding the ratio of motor to axle. But if you plan to run smaller tires then it has a lot to do with it. On my car I am running 13/16" tires and a 28t is the largest gear I can put in and still make ground clearance.

Which by the way is being raised to .062.

So for all the rule junkies, the minimum clearance is being raised from .055 to .062. Scream all you want, it'll fall on deaf ears at my end. I tested my car for 161 laps and noted some very observable tire wear!
In order to make a set of tires go two races we need more clearance and that is just common sense.

[chief32s]

Very sensible.

I was working on .062 anyway so it doesn't affect me.
Al

[One_Track_Mind]

Hmmm serves me right for building ahead of time.
Will have to see how this new ruling affects my car.

Won't SBR rubber wear a little more aggressive then natural rubber tires?
And also, doesn't the track conditions declare on how the rubber will wear?

Just curious.

[Jairus]

Well, that is why I wanted guys to build and test early so we can get the bugs out of the program. As for tire wear, I don't have enough experience racing to know. Maybe one of those "speed crazed racers" will chime in? Next trip to the track will include a set of Natural rubber wheels to swap in and see how they compare. But don't want to change too much or it becomes a new car and just like starting over.

[HarV Wallbanger III]

Thanks Jarius.
BINGO!
"Tire wear will be a factor Jairus with big motors..... I think 3 min heats is good." post 181
Going to .062 will prove a good idea.....IMO

"and noted some very observable tire wear!"

Both types will wear but natural should wear a little less. The motors spinning the rear tires is whats doing it for the most part.....

[Foamy]

I'm thinkin a 24 is going to want something around 5:1.

What do you paint the Ray bodies with so they don't die a quick explosive death?

[Jairus]

Lacquer for the graphics and stripes then Parma FasKolor for the fill.
Prep is the key when using water based paint. I scrub the body with steel wool to provide "tooth" then wipe it out with 91% alcohol prior to masking and after masking to remove all skin oil.

[HarV Wallbanger III]

So you are going to .062 for the first race and the 2nd race gets ran with what they have left or does the car have to clear .062 for both races??

[Jairus]

Read the rules Barney.
"No maintenance between races and if the car breaks or fails, it gets sent home". And, if the chassis hits the track on the second race it is done! Plenty of room for wear in those rules. Even my Flexi racer could make it 2 and sometimes 3 races on a single set of tires and that was way heavier.

[MantaRay]

What type of gluing are we talkin' about? Normal Spray glue?............Are the tracks going to be "Rubbered Up" or A relatively freshly sprayed track. It is an important variable that will help determine how a car is setup.

[One_Track_Mind]

I was still waiting on hearing about braid depth? And you think this ? Will get answered Ray?!

[Jairus]

Both of your questions were answered last week. Please check post #5 as that's where all updates will be posted in the future so they don't get buried.

[MantaRay]

Thanks Jairus............
Leaving the gluing/condition of the tracks up to the Track owner.............makes tire choice just a crap shoot. If one track is totally different than the other..............Oh Well......................Hello Wall

I personally have never seen a "Flush" track.............Maybe copper tape...lol

Sure would like some input from folks that race at the two tracks