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Old 03-29-2008, 01:51 AM   #1981
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I made the +5 degree block. It was not too hard. You can see in the photo the kingpin tilting inward at the top as if there were -3 camber on the tire but the spindle tilts downwards a bit at a 2 degree angle going to the tip. This should restore the low roll center that the car would have with typical road course cambers on both sides. I'll see if the car performs any better on the oval later in the week. Photo upload did not work.

Note that that lower arm is completely fixed. If the lower arm angled up from the chassis at a 30 degree angle but put the lower kingpin pivot in the same position, the roll center would be the same as with this shimmed up horizontal arm. You do not put fixed members into a roll center diagram. You use instead a line at right angles to the pin for the lower instant center line.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-5-degree-steering-block-001.jpg  

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Old 03-29-2008, 12:40 PM   #1982
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Originally Posted by John Stranahan View Post
I made the +5 degree block. It was not too hard. You can see in the photo the kingpin tilting inward at the top as if there were -3 camber on the tire but the spindle tilts downwards a bit at a 2 degree angle going to the tip. This should restore the low roll center that the car would have with typical road course cambers on both sides. I'll see if the car performs any better on the oval later in the week. Photo upload did not work.

Note that that lower arm is completely fixed. If the lower arm angled up from the chassis at a 30 degree angle but put the lower kingpin pivot in the same position, the roll center would be the same as with this shimmed up horizontal arm. You do not put fixed members into a roll center diagram. You use instead a line at right angles to the pin for the lower instant center line.


Hi John,

Good stuff here, keep up the good work.

Your latest steering block mod reminds me of something we did back in the day when the only option was Associated old style block front end. We used to drill out the steering block king pin hole at angles to alter the performance of the old block-style front end.

Frank Calandra
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Old 03-29-2008, 12:54 PM   #1983
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Frank-Thanks. And by the way my Shop Manager, Jeff, is interested in getting some of your 1/10 road cars and the Battle Axe through a distributor for store stock if possible. Give me a PM with estimated times.
John
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Old 03-29-2008, 07:43 PM   #1984
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I installed the +5 degree block on the oval cars left front. Here are some observations.

BUMP STEER
We have discussed bump steer earlier in the thread in conjunction with the servo flat mod. Bump steer is when the wheel steers a bit more (or less) as the tire goes up into bump. It is easy to tell if you have it. Push the front wheel up with your finger and watch the tire. A little bump toe out is OK. Bump toe in may make the car react too suddenely as it rolls in a turn. Several of us have tilted the front of the servo back up in the front after trying the servo flat mod onroad in 1/10 scale, and we now run the steering links off the bottom of the servo to keep bump steer in control. In other words we are back to the standard pan car arrangement.

I have noticed that on cars that you eliminate bumpsteer the steering links point right to your instant centers. I have eliminated bump steer on both side of this oval car by raising the links up on the servo saver. The steering links thus point right to the instant centers on both sides. Note that these instant centers are below the lower Arms. The lower arms can not be used to determine the instant centers. The roll center is thus nice and low now. Probably near the ground. Note that on a road car I did not have enough steering throw with the rod ends on the servo saver on these upper holes. The radius of the servo horn is a little short. It may work on the oval as we don't need as much throw.

Caster induced Wedge
If I shot a video with this front view of the car and turn the wheel left you would see the left front corner of the chassis lift. That takes weight off the front right and adds weight to the right rear. In other words it adds wedge which helps steering. Normally this is produced by the caster in conjuction with the camber of the tire. This effect is now more pronounced with the +5 degree block. The chassis lifts more than before. This is the result of the way the spindle moves now around a kingpin at angles to it. This works fine for the Ford Focus, it should work fine here. If I get too much steering I can cut back or remove the part. The goal is to reduce scrub.

Ackerman
Ackerman lets the front end take a corner with the front tires set on different radii. The inner tire takes a tighter turn.
The lower holes in the servo are more widely spaced than the upper holes. This makes a slight change to less ackerman. Maybe this is good or maybe not. I'll see when I test. If the part makes it into the race I will have some lap times.

John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-5-degree-steering-block-installed650.jpg  

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Old 04-02-2008, 03:47 PM   #1985
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Track Report-

One of the tips the oval guys have is too look at your tire wear. If they are wearing even left and right then you are doing a pretty good job of preloading the left. You can do this with your dial caliper by measuring the O.D. of the tire after a race or if the track has any traction by looking at the rubber bits the tires are leaving on the underside of the body. My fronts are wearing more even now and are leaving a similar amount of rubber bits but the bits are not quite in the same place. The left front leaves them in a pile under the back of the left front fender. The right side tire is now leaving a few more bits on the inside of the passenger door, but a similar amount as the left.


+5 camber left front steering block (arm).
I described this piece in my previous posts. It adds 5 degrees of positive camber to the left front tire so that I can then set the kingpin at a negative 3 degrees like the other side. The result was wonderful. The car felt like it had a low roll center now. Corner entry grip was improved scrub was absent. The car required very little steering throw to accomplish the corner. If you are doing flat oval on asphalt I highly recommend you try this and give me a report back. A manufaturer could easily make this as a tuning piece for this associated front end. The left front is working harder now than ever based on wear and rubber bits on the body.

I tried the battery 1/2 inch forward and all the way back. I prefer all the way back from a handling view point. I did not get lap times. The car just has better forward traction all the way back. This helps a lot on corner exit. My battery lead wires are 1/8 inch in front of the rear tire.

I moved the receiver and transponder to the left edge. This put about 1.5 more ounces on the left side toward the front.

I took another .75 ounces out of the car by removing chassis in front of my body posts which are just in front of the inner a-Arm pivots. I removed chassis under the servo.

The Ackerman change (see above post), though slight, must be OK as the car handled super.

The HPI clear rear wing from 200 mm Nitro allowed me to remove the spoiler. This should streamline things a bit.

Gearing is about 3.14 inch/rev rollout.

Throttle Roll On
Today traction was only low to medium due to some drizzle and rubber dust from a big race. I ran my wide pan car on the oval and practiced rolling on the throttle with LiPo and a 6.5 motor. It is just remarkable how rolling the throttle on just a little slower will make the car jet out of the corner a lot faster. Newcomers to pan need to practice this a lot. The car handled well. Can't wait for a dry day.


John

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Old 04-03-2008, 05:14 PM   #1986
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Well the car was strapped today. Mike asked if I was running a 10.5. Well no.

Novak 13.5 sintered rotor upgrade
Here is some more data on the 13.5 Novak. If you buy the EX motor with the speed control, you can upgrade it to sintered rotor and large bearing for about $25. Thats a pretty good deal. Now the SS13.5 motor comes with a sintered rotor. This is a better deal if you use a different than XBR speed control. Now the new item learned today is that the upgrade sintered rotor is the big 13 mm one. The ones that comes with the SS13.5 is a small standard size sintered rotor. Now the way we use this motor on the oval is more or less constant speed grunt. Increase throttle only by 10% on the straight. The big rotor should be the ticket. I tried it and it felt good in the car.
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Old 04-04-2008, 10:32 AM   #1987
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MLP Viper X10

Here is a spy shot of the new Viper X10 Prototype. Marty Peterson has sold the company to Chris Cunningham, I believe, The transfer will be complete around July. I hope this car makes it to production.

Some novel features for a pan car include a double dynamic arm (lower A-arm and upper camber link) Front suspension that is fully dampened by two angled shocks. The shocks on this front end should make this car perform better on bumpy outdoor tracks. If it is sold separate the front end alone may be a hit on the velodrome as it is nice and low.

Another nice feature is a top plate that extends the rear body mounts farther back on the car. I have done this to my 3-link prototype as well. This adds stability to the back end of the body and the wing so it does not flop up and down.

It should be LiPo capable.

This web site is in transition and does not always load for me. Here is the link. http://www.mlpmotorsports.net/

A kit to convert the car to 235 mm may be offered.

It is hard to tell what the rear suspension looks like, but it is dampened by three small shocks and looks like it might have a T-plate or flex plate center as the typical football for the center pivot is absent.

Any of these features may change as this is a picture of an early prototype.
John
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-pro%2520viper.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-mlp-gt2-b.jpg  

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Old 04-04-2008, 11:08 AM   #1988
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that frontend looks low, but just how low is hard to tell.. i wonder if it will fit under an lmp body or just oval/gt bodies
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Old 04-04-2008, 12:00 PM   #1989
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Tally-I believe that that front end will accept almost all ot the current GTP bodies. I know that Marty had aquired a Peugeot 905 B body about the time he was making these prototypes. I put up a new front end pic of an early prototype. This prototype had a CRC pantoura pivot ball side link rear suspension. I don't see a place for that center pivot in the frame pics that they are showing.

A newly designed LMP body could be lower in front of the suspension and just have the huge scoop they seem to have center front now start about were the front shock tower rises. The servo fits in the forward part of the canopy. Maybe C. C. can comment.

John

PS there are a lot of pleasant discussions with Marty Petersen earlier in this thread.

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Old 04-05-2008, 10:19 PM   #1990
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RACE Report
The 200 mm 3-link was victorious again. Fast lap in the first heat was only .020 sec less than Mikes. A lot of the time we run very similar laps. This makes the race exciting.

#5 degree steering block
Traction was off just a .1 or so in the first three heats. There was some black dust collecting on the frame after a run. For this reason I did not get a good evaluation of the block. I did notice in the main, I was able to make up time on most of the cars and ended up with a 2 lap lead due to incidents and lack therof on my part. Traction was a bit better in the main. My rubber dust plumes off the front tires on the underside of the body were very even left and right. I'll check tire wear tomorrow. There was very few of these rubber bits in the first heats due to the dust, although traction was medium.

Gearing
The oval guys have come down to about 3.14 rollout these days and I have come up to exactly the same independently. Novak 13.5R 4 cell 175 foot flat oval.

I had bad luck right in the beginning and fried my late model LRP TC edition due to operator error. I replaced it with an early model LRP sphere comp just in time for the first heat. I swear you can feel the extra punch from the TC edition and short fat wires. I missed it

I did not try the COT body. It feels fast in practice but is only really hooked up in high traction. Traction was off just enough not to try it.

John

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Old 04-05-2008, 10:30 PM   #1991
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Hi John

Marty has told me of you and after reading for almost 3 days on all that you have done here I would say Marty was right when he said that you had some real innovative ideas and technical info on Cars on this forum and I must say he was right Man you do a lot of testing and making things work it must be a love for you, as it is for Marty I get calls all hours of the night from him and his Ideas all the time kinda makes me at times.

The X10 you have pictures of are from his first and 2nd prototype the cars he has sent me (sorry no pics yet).
I have the final run of this chassis and it has a shock frontend like you see in the picture, you can drop the chassis to the ground or go the other way almost a full 10mm front shock tower is low and you can mount any body out there right now.
We did move the shock tower back almost 5mm just to keep the suspension inline and it also has a standard D-Drive front suspension (pan car) or (strut Suspension) that is mounted on carbon fiber plates (spacers) or inplace of the spacers.
The lower Chassis is narrow in the front more like a touring car and has a touring car bumper and body mounts, we are running a link to link rear pivot setup much like that of the Hatzenbach Chassis used on his 1/12 scale car and his 1/10 scale car.
We are also going to try one more rear setup to see how it works but what we have now is the best I have seen and works well with Martys front end suspension system it worked so good we had to make the front softer as in front spring so we could get more front traction and now from high speed corners to low speed corners the car work better than anyother car I have tested these days.

Pictures and a press release should be out around mid may ok Guy's
Thanks for your time and Questions on MLP and CLC Racing.

C.C.
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-x10-base.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-mlp2.jpg  

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Old 04-06-2008, 03:27 PM   #1992
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Chris-Thanks for the response. Good luck with the new Company. Exciting stuff on your prototypes.

Here is a pic of the 200 mm 3-link oval car on the underside of the body after 3 heats and a main. You can see the pattern the right side (laden tires) made up above, the front is to the right. Note the even amount of rubber bits on the left and right side. Tire wear was more even. This along with the even pattern left and right on the back tell me the weight is placed about right in the car. I used Jack the gripper for every heat this time and tire wear was less. I only applied it for about 5 minutes before the race rather than my road course treatment of about 20 minutes. The front tires at 2.34 inch with two full races and one practice on them; wear is about .030 for each race on the pink fronts. Wear on the pink rear is only .025 inch for each race.
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-rubber-bits-002.jpg  

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Old 04-06-2008, 06:28 PM   #1993
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Thanks John,
Marty is still and will always be the designer he comes up with the Ideas I make the parts or have them made and me and my friends do a lot of testing miles upon miles of laps to see how the outcome is.

I do know That marty never stopped working on the JPS (John Pantoura Stranahan) Chassis your 3 link setup that is I have not got to test the car Marty has run it a few times, however I did see it weeks ago when I went to see Marty, I must say it is a work of art, Marty always looked for a away to make a floating rear end suspension but when he found what you were doing it was just what he had inmind and you did all the work. That is why Marty Called it the JPS Sidewinder Chassis, and he also thanks you on the website for it as well. It Looks Killer with your rearend pod setup and his frontend setup. and he said it works like a dream but has yet to race it. the only thing is this JPS car will not be cheap to make.

So people do not look to see a cheap price on this car ok. It is an all out racer!!! more inline with the Nitro 1/8 pro cars here.
I can not wait to test this car!

Well keep up the good work John - Love what ya do here!

C.C.
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Old 04-07-2008, 09:32 PM   #1994
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Chris-Thanks for the report. I look forward to your car introductions.



NiMH Battery Report
If you have followed the thread, you probably know that I am not a NiMH fan. I had not tested any since IB introduced 4200's, though.
The club chose to go 4 cell over my objections, so I now own a IB 4600 and an EP 4600 both matched by Trinity. I have owned one for about 4 weeks, one for about 3 weeks. Both have about 15 cycles. Original tests at about the second cycle showed good capacity for both, around 4900 mA-h. One has lost 24 % of its original capacity. One has lost 28%. By some industrial standards they are both shot at this point. (A loss of 20%). Voltage on the EP was still good but was the best on the third cycle at 1.25 V/cell. On the first cycle it was about 1.20 Volts/cell. Now this battery is still good for my oval use, but both would be dumping in the touring car already after 3 weeks of use (if they were 6 cell packs). This is not economical at all. The four cell packs ran $70-$80 and are hard for the hobby shop manger to find from normal distributors.

ps. you can make a car just as slow using a LiPo with a higher turn brushless.

It takes a good 50 cycles on various brands of LiPo's in a High Drain condition before they lose this much capacity. The brand of FMA LiPo, I am using now is showing to be about twice as good on holding the capacity. They still sizzle in the car after 25 + cycles.

How to get the best from your NiMH
This has not seemed to change. You get a little better performance on 2cnd and third cycle. This even showed up on the Turbo thirty's third cycle. Use the same pack for the whole race and one practice. If you charge the night before it won't have as much sizzle in the car.
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Old 04-10-2008, 01:57 PM   #1995
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GTB 4-cell Spread Spectrum ESC

I purchased one of these while my fried speed control is being repaired. (the failure was my error). There are several reasons to choose this control for 4 cell stock or super stock. Firstly The specs (on resistance) are as good as the full size GTB. Secondly things don't really get too hot in this class and you can do without a fan and big heatsink. This allows you to experiement a little with placement in the car and reduces weight. The wires are 14 gauge where the GTB has smaller 16 gauge. I replaced the wires with 12 gauge. I put the speed control left back on the pod. It was a good fit here. This takes the motor wires out of action as far as pod roll is concerned. The wires will not limit movement. The battery wires still do but they are longer so there is not much stiffness there. I also wanted to try weight farther back on the car. I had already noticed I prefered the batteries all the way back.

Although front right tire wear is improved it is still wearing the fastest.

Spread Spektrum Optimized means that the on-to-off and off-to-on time of the transisors is now optimized without having to worry about radio interference. This gives a slight (probably unoticeable) increase in performance due to faster switching.

Note that I don't cut the rear of my body out due to windtunnel tests I did earlier in the thread, so the speed control is protected well enough.
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-gtb-4-cell-002.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-gtb-4-cell-installed-rear-view.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-gtb-4-cel-installed.jpg  

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