MM/PS HELP

[Eagle Racing]

I always try to offer help after a race on my track to anyone that would like me to look over there car.

I had one taker. So I thought I would post a pic and talk about the car.

This particular car made no full passes, even with the body off it de-slotted. First a little info about the car. The tire diameter on a BSRT Tire Sizer the metal one, measured .466 diameter. That is ok, except they are rock hard. The gear is a 22T crown with a 8T pionion and that is ok. The chassis is a BSRT G3 except it uses a east/west brush setup like AW or Wizard cars. It does not use the standard G3 brush setup. The armature is a Wizard green wire 3ohm. The car has braids.



KEEP IN MIND THIS IS JUST MY OPINION

1. Tires are to hard no bite. When it did launch it spun bad and then de-slotted.
2. Traction magnets cut down, not enough down force for the Blacktop. (lots of racers did this)
3. All I did was install poly traction magnets and install my rear axle setup.
4. That axle is a 20T crown with a 8T pinion.
5. My tires are .450
6. The result was a .465 pass without the body. That would have QTd the car in around #6 or #7.
7. Could the car be faster? Yes, easily just add better motor magnets. The ones in it are stock ceramic.


As far as gear ratio and tires go you must dial those in according to the power of the motor and magnets. To be fast you have to try different setups. The build sheets are nice for beginners and a great starting point. If you just do that and try nothing else you will not get to the really fast times. I hope this helps, if you have more questions please ask. 

[AJR]

Very good info. Eagle. I used the build thread to build my first MM/PS last year and it was a mid pack car, but I was not able to spend a lot of time tuning it then. This year I put in the time and only after extensive testing with gears and tires did both my cars finally wake up. I learned a bunch about these cars during that time. I ended up running a 7t pinion, 23t crown, braids, silly foams, BSRT 140 arm. All other electrical components are stock ( shunts seemed to be more trouble than they are worth...for me anyway). Still think there is a little more there. Going to try some new motor magnets I just learned about and start the process all over again to be ready for Atco in April.

[pceng]

Hey Rob,

Thanks for the information!

Knew the tires were hard, came from an unrestricted Decosmo, that I built 3 or 4 years ago. Only black tires I had that would fit. They were holding at 22v's, guess the voltage difference was too much for them.
Very curios right now about the mtr/mags. The magnets in the car are matched ceramic (Lucky Bobs). What magnets were you referring to. See that Jeff, said something about the mtr/mags also. If stronger ceramics are available I have no knowledge of them. Please any info. on such magnets would be greatly appreciated. What they are, who has them, and so forth.

...............................tia, Peter

Did not see PM till few minutes ago, all cool.

[AJR]

Peter BSRT and Lucky Bobs lists the motor mags. #277 and #290. I was going to PM you with this question, but I will ask here since you referenced your test voltage. Is that a wall wart you are using. I've been thinking about your green FED and why it deslots here, but not for you. If you are using a wall wart then that has no amps available for these higher end cars. Huuuuuge difference. My first test track before Bear Creek was a 10ft Tyco with a homemade timing system on a 22v ww. I started buying material for my track and when I bought my power supply I connected it to the track. At the time I was building my first unlimited 4g (Regulator) for a match race with Robert. I was blown away at the difference at the same voltage. I've seen power supplies out there recently that are going pretty cheap $125 - $150. You might want to start saving for one. As for the FED, I would like to see it run again. You might want to try lowering the traction mags a little more and maybe wheelie bars if that doesn't work. Anyway....for what it's worth.

Jeff

[pceng]

Hey Jeff,

Have to check on those magnets, thanks! And yep, wall warts. Right now my test track is 15" and 13v. My 22v is at Dougs. Used one for each lane for race.
Spent some time to cut down wheels and tires for FED going to try smaller diameter to get mags closer to track, before going back to wheelie bar. Was also going to look at LL T's traction mags (being taller). Thought it might stay down this time, but that could also be the pinion now playing into things a bit more having gone to a 8T.

...............gotta look at those mags now, thanks, Peter

[SKR]

Oct 29, 2008 9:18:14 GMT -7 SKR said:

So you want to build a MM/PS but are unsure how? I'll try and not confuse you anymore than you might be

This class has been around for about a year. The MM/PS class was developed here at PSD by Chuck and myself as a class that would be highly competitive, only take intermediate skills to build one, fast, and not break the bank to get into.

We're always searching for more speed. I'll pass on any helpful tips as we learn more.

I laid out a helpful "suggested parts list" in the MM/PS proxy sign up thread:

www.psychoslots.com/index.cgi?board=general&action=display&thread=796

This is some great info passed on by Eagle and JJ. I'm happy you were able to get some pointers from my build thread JJ. I made the thread before the first ever MM/PS proxy race to show racers what works on our track. As always, all tracks are different and will require different set ups. Like Eagle said you really have to play around with different set ups to see what works for you and your track.

On that note; It looks like some changes are coming again to the track surface at Drag City USA. I'll be sure to pass on any helpful info I can as for whats currently working before our Spring Nats.

Helping out each other is what this site and hobby is all about, I think a set up thread for each NTRA track would be a good thing for all proxy racers to get their cars into the ball park. Nothing major, just the basics like gearing, tire size, braids or no braids etc.....

Cordell, can you move this to "Tech Tips"? I think it would be better suited there.

[AJR]

Jan 14, 2014 17:37:15 GMT -7 SKR said:

This is some great info passed on by Eagle and JJ. I'm happy you were able to get some pointers from my build thread JJ. I made the thread before the first ever MM/PS proxy race to show racers what works on our track. As always, all tracks are different and will require different set ups. Like Eagle said you really have to play around with different set ups to see what works for you and your track.

On that note; It looks like some changes are coming again to the track surface at Drag City USA. I'll be sure to pass on any helpful info I can as for whats currently working before our Spring Nats.

Helping out each other is what this site and hobby is all about, I think a set up thread for each NTRA track would be a good thing for all proxy racers to get their cars into the ball park. Nothing major, just the basics like gearing, tire size, braids or no braids etc.....

Cordell, can you move this to "Tech Tips"? I think it would be better suited there.

I knew it had been posted quite awhile ago, but still excellent info. for a beginner. I had never built a SG+ before last year and it was literally my blueprint. I do a lot of reading of the tech info. here and since I have a track....I like to test the cars. I also like the idea of the track set up thread, that would be good info. to have. That's something else that I do is reference past races for set up and other info., so it would be great to have it all in one spot.
 

[AJR]

Jan 14, 2014 13:27:22 GMT -7 pceng said:

Hey Jeff,

Have to check on those magnets, thanks! And yep, wall warts. Right now my test track is 15" and 13v. My 22v is at Dougs. Used one for each lane for race.
Spent some time to cut down wheels and tires for FED going to try smaller diameter to get mags closer to track, before going back to wheelie bar. Was also going to look at LL T's traction mags (being taller). Thought it might stay down this time, but that could also be the pinion now playing into things a bit more having gone to a 8T.

...............gotta look at those mags now, thanks, Peter

Peter I shimmed my FED traction magnets to get them lower without sacrificing tire height. But that depends on what size tire your car likes. FYI......unless you've already thought of that.

[pceng]

Hey Jeff,

I'd say whatever size will keep it down right now....lol. Thought of trying traction magnets from LLT, them being taller by some than stock 4g's they might be fitted in small hole on top of mag pocket. Got to dig up a pair of them and check it out. Have a pair of 290's, think they were in the MM/PS till I got the matched mags. Is there a big difference between the two? Have not had chance to measure and compare, will get to that tonight.

...............................Peter

[AJR]

On the FED I would shim them to get them closer to the track and that should do it. That's actually what I did to it when it was here and got it to stick good enough to shear the gear. I really want to see that car get down the track. I think it will be fast. As far as the MM/PS magnets. I don't know what the difference will be between the 290's and the 277's. Sam mentioned them in a PM during the race and acted like they are a performance improvement. So I thought I would try them out for myself. I'm running 290 in the Firebird and Lucky Bobs matched magnets on the Camaro. I am ordering today, so I will let you know how it goes.

[pceng]

Jan 16, 2014 6:46:41 GMT -7 AJR said:

On the FED I would shim them to get them closer to the track and that should do it. That's actually what I did to it when it was here and got it to stick good enough to shear the gear. I really want to see that car get down the track. I think it will be fast. As far as the MM/PS magnets. I don't know what the difference will be between the 290's and the 277's. Sam mentioned them in a PM during the race and acted like they are a performance improvement. So I thought I would try them out for myself. I'm running 290 in the Firebird and Lucky Bobs matched magnets on the Camaro. I am ordering today, so I will let you know how it goes.

Hey Jeff, did not get chance to measure mags last night. The matched magnets I have came from Lucky Bob. Have a felling the 277&290's may be stronger. They both list separately as level or grade 4 the 277's being the high downforce version. They are pointed out as parts included in some of the hotter rolling chassis/with 3ohm arms.

If I remember right I may have lowered the t/mags on the FED again since you had the car (too many cars and no time). Think it will go mag, tire, wheelie bar. Maybe the first two together depending on how close I can get t/mag. It will stay on track one of these days.......lol.

When you had the car I think the pinion shifted. The teeth of the crown were laid over, but section of pinion teeth that meshed with crown no longer existed. The length of the teeth was about a third of what should be on pinion.

............................... Peter

[AJR]

The run that it broke the gears it launched better than it ever had. If I remember right, I did 1 or 2 short blips first and kind of a rolling throttle run to see if it was going to stick and it did. Looked quick too. On the first full power launch for a time, it launched great and stripped gears at about 1/4 track. Want to see it go. That car has been at every FED event if my memory is correct.

[SKR]

I was intrigued by hearing about the strength of the BSRT 277 ceramic grade level 4 "high downforce magnets" so I decided to order a pair to try them out. Here is my first look at them and thought I'd pass on some testing to you all. Tomorrow night, I hope to do some track testing and will let you know if they are worth the hype.



My strength testing is by no means near as accurate as it would be with a Gauss meter but it will show you how they compare with other magnets.

First up, I put a stock set of Super G Plus ceramic motor magnets on the scale to see what the negative pull ratings were. I have seen a good set of stock magnets pull as much as -25.0 after being zapped. Ranges from the -20 to -21's are fairly typical for untouched stock magnets. Downfall on stock magnets even if you do zap them is that they will lose their strength and will continually need re zapped.


Next up were the BSRT 290 G+/G3/G3R BONDED MOTOR MAGNETS CERAMIC GRADE LEVEL 4 . The 290's strength stays consistent which make these a great upgrade to stock motor magnets.


Next up; BSRT 277 G3/G3R BONDED MOTOR MAGNETS CERAMIC GRADE LEVEL 4 HIGH DOWNFORCE. Quite a huge jump from the other level 4's. These do have a bigger foot print over the 290's and as you can see they have a much greater pull over the 290's.


Next up; BSRT 292 G+/G3/G3R BONDED MOTOR MAGNETS POLYMER GRADE LEVEL 10. Although these are not legal in MM/PS I thought I'd show them how they pull to maybe put things into better perspective.


Here is a picture of the 277's and 290's to show you all the difference in size. 277's are on bottom.


The most noticeable difference visually is the shape of how they are molded. 290's on the right, 277's on the left. They have a different cut on the side close to the armature.


Well that's it for now. I'll report track testing on Sunday. Note that these 277's and 290's are of the same grade Level 4. They are totally legal in MM/PS so I'm excited to give them a try.

Dec 23, 2009 10:57:27 GMT -7 SKR said:

With the release of BSRT's Ceramic bonded motor magnets for the G3/G-Plus cars...... there has been questions coming up as to whether they would be legal in ISRA's MM/PS class.

I was able to do some testing this week and would like to share the results with you.

My base test car was my Larry Morgan Mustang that TQ'd this past week with a .3690 E/T and won the final with the same E/T. Once I powered up the track for some testing I made two more runs before switching motor magnets.

Old Ceramic Magnets

Run #1 .3727 @ 40.83 mph
Run #2 .3745 @ 40.58 mph

After tearing down the car and checking the magnet strength on my cheap pocket scale I found that the magnets read

South magnet - 20.0
North magnet -19.1

I found this odd because on Friday before the race I re-zapped them and they were both reading in the -23. range. With only about 6 runs on the car they magnets have already weaken.

Bonded Ceramic Magnets

Before I put these into my chassis I tested them on the scale.

South -23.4
North -23.2

As far as E/T'S

Run #1 .3745 @ 39.64 mph
Run #2 .3706 @ 39.41 mph. Car was cooled between runs.

Magnets were retested for strength after testing. No difference at all.

South -23.4
North -23.2

As you can see by my results I lost some mph which tells me I might be able to lower my gear ratio a little.

So what does this all mean? Stock Ceramic magnets are a crap shoot for sure. Some guys buy many sets to try and find a decent pair to race and at $6 a pair, that can add up quick. You can Zap the magnets but as we have seen here..... they only stay charged for so long and then need re zapped. Not until this past Summer did we have a Magnet Zapper here which has been a great help for us in this class. I know having a Zapper is not in most racers budget as was ours but we came came across a deal that was to good to pass up. The best set of Ceramic magnets that I've seen read -.25 on my scale.

Many road race clubs that race the G cars have made the switch or are about to and I've read that some will allow both which sounds fair to me.

As of January 1, 2010 these magnets will be legal in ISRA's MM/PS class as will the current stock ceramic motor magnets.

Part #
290 G+/G3/G3R BONDED MOTOR MAGNETS CERAMIC GRADE NEW!!! $10.00


Lucky Bob's has them:
www.lucky-bobs-slot-cars.com/index.html
Scale Auto has them. Not listed. You have to call them
www.scaleauto.com/

and I have seen some listed on Ebay.

[AJR]

Thanks Sam for the info. I use the exact same method for measuring my mags and the same scale. It was probably another one of your posts that I got the idea from. I was going to do the same thing when I got my magnets that I ordered. I am excited by this because it looks like a definite performance gain. Looking forward to your testing info. to come. I will post the same when I get mine, as a comparison on the different surfaces.

[SKR]

no track testing yet, Waiting on MM/PS to arrive to rebuild it with the 277's. I'll post results next week.