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Peregrinari
2008.05.09, 01:08 PM
Ok guys, I thought starting a thread for our club was not a terrible idea on this one. I know a few of you have bought these and are working on getting them going. A couple of notes that I have after installing the bar.

1. Don't tighten down the bar so it doesn't move. Then you are essentially creating a torsion bar front end and as we know, thanks to Dodge, that torsion bars suck as far as spring systems go. The bar should be secure in its mount but should move freely. I believe the reason people are thinking that the bar stiffens up the front end is simply because they tighten the bar until it can't move and then as I said this results in the torsion bar effect.

2. The pads that the shock springs sit on is about 6/10 of a millimeter thick, in effect pre-loading your springs quite a bit. Therefore take this in to account. What I ended up with is PN AWD light blue low-down springs plus 1.2 mm worth of spacers under the ride height limiter. In the process, I had to grind down the ride height spacers so that there was enough travel in the suspension. This makes for a super smooth working front end with superior springs as the AWD springs seem to be more consistent in there compression than the 02 specific springs.

3. If you do not use the lower arm bar from PN, you will need to cut about half of the molded in double brace on the pan itself. If you do not do this, the roll-bar will not work right and it will bind.


That said, I am blown away that the system works and appears to work quite well. I haven't had a chance to truly track test it yet but the theory is sound. Wheels are coupled (minimally) to one another therefore when going in to a turn (especially at higher speeds), the bar acts to make the front end roll less and squat more, therefore getting better traction and as a result better handling with less hop or breaking lose.

One other interesting caveat is that the roll-bar seems to act as a damper as well, soaking up a good deal of the unsprung energy instead of it being translated in to bounce when bumps are encountered.

I took the opportunity of having my car apart to polish my kingpins (In a drill of course) with Noxon metal polish as well. Wow! what a difference. I thought the knuckles were smooth before but man the polishing made them even smoother! Definitely a worthwhile upgrade. All these little things are important. Physics don't take a break just because the car is small. Anything I can do to keep things smooth and tight are rewarded with less work to keep the car going straight as well as sticking to the turns.

Overall, I think this thing is going to work and I was the biggest skeptic about it. Only time and testing will tell though. Build quality is excellent and installation is straightforward.

http://mini-zracer.com/mini-zgallery/data/500/medium/P10102451.jpg
http://mini-zracer.com/mini-zgallery/data/500/medium/P10102461.jpg

Hope this helps guys! See you next weekend!

Tom

TALLGEESE
2008.05.09, 07:42 PM
Tom, nice job on the write-up about the roll-bar, very informative and the pics look fantastic.. Looks like you did a really good job grinding off the upper suspension arms on the front end of that MR-02.. That car looks great.. As far as polishing the kingpins goes, for me that's a must for any Mini-Z.. I even polish the optional Kyosho stainless steel kingpins for a really smooth ride.. For the ultimate in smoothness, you could try using the Kyosho Fluorine oil or powder on the kingpins as well... Since you're running the 0.5 degree{caster} tower bar in the front I'm assuming you got the kit from PN that includes both the 0.5 degree tower bar and the roll bar together??

Overall the car looks like it's going to be a good performer on the track.. Now all you need is some track time to help dial-in and fine tune you're settings..

Peregrinari
2008.05.09, 10:44 PM
Thanks for the complement man. For the suspension arm removal, I used a very sharp box knife and took a little off at a time. In reference to the kingpins I am actually running the Atomic Stainless pins, I found them to be far better than stock, and as I said; now that they are polished, they are smooooooth. I will have to try the oil or powder if I get a chance to pick some up. I need to get that, some comm drops, and some motor spray. I keep forgetting to get those things! As for the Caster bar, yes I bought the kit with the .5 caster bar and the roll-bar all in one. Seemed a good deal. Talk to you soon!

Tom

Tjay
2008.05.10, 03:39 AM
your spring is too loose... use the limiter/cup. They sell the low down springs for MR02 as well. You might want to check that out.

Thanks for sharing and nice pics!

Peregrinari
2008.05.10, 07:08 AM
Yeah, It seems to be but when I push on it forward back left and right, it doesn't move or seem to affect it's compression. Though it looks rather odd, the spring seems to function very well. I need to order some more springs for my 02. I have loads of springs for it but none are low down and none are quite as soft as I like. I need PN greens is what I need.

Tom

Tjay
2008.05.10, 11:45 AM
yeah, I'm running PN greens...

TALLGEESE
2008.05.12, 10:26 PM
This past weekend I finally got a chance to test out the PN roll-bar kit...

I tried the roll-bar kit on a Rear-Mount MR-02 with the Epson NSX body and the stock 2 degree offset wheels.. I had heard about people running the roll-bar on the PN and Atomic pancars with good results.. So I figured I would try it on a relatively wide wheelbase car to start off with..

I really liked the results, the car felt more stable overall and also made the car handle more precise. The car handled good before, but felt relatively numb in the corners with a slight bit of understeer.. After installing the green roll-bar{the softest of the two PN roll-bars}. I noticed the front end of the car felt more planted.. It also felt more predictable at higher-speeds and that allowed me to push the car harder.. One thing that surprised me was that the front-end of the car didn't feel stiffer as I had heard this was one of the characteristics of the PN bars..

As far as car setup the only thing that I changed was the roll-bar so I could tell if the PN bars were really doing there job.. Before installing the bars my NSX would push slightly going into high speed corners.. Now the car didn't push at all.. I actually had to turn down my steering travel a tiny bit to keep the car from turning in too quickly.. As far as my car setup in the front I was running Kyosho red springs{no spacers}, with the shortest spring cups/limiters along with 1 degree camber PN knuckles and 30 degree Kyosho narrow slick tires.. For steering I was running one degree toe-in along with a one degree caster PN aluminum upper tower bar...

Overall I'd say that the PN roll-bars did they're job.. I haven't had a chance to try the harder orange PN bar on the front yet.. I was so happy with the way the car was handling at the time that I didn't feel like changing out the green bar for the harder orange one.. I'll have to try the orange bar out sometime in the near future..

Tjay
2008.05.13, 02:49 AM
my quick review:

Understeer when coming in on a turn off throttle. Coming out is good, front is really planted and I don't see the front wheel bouncing/chattering around but still pushes. I like it on throttle in the sweeper but not off throttle exit...

I test all the parts through lap timer;

9.50 with s-bars
9.20 w/out it

Please see our track for reference... click my sig to see our recent track layout.

VAzRACER
2008.05.13, 05:03 PM
my quick review:

Understeer when coming in on a turn off throttle. Coming out is good, front is really planted and I don't see the front wheel bouncing/chattering around but still pushes. I like it on throttle in the sweeper but not off throttle exit...

I test all the parts through lap timer;

9.50 with s-bars
9.20 w/out it

Please see our track for reference... click my sig to see our recent track layout.

I saw the same results you did, I wasnt able to time the car but it felt slower with the bars so I took them off early on in the day. I'm going to try them with different cars later. I did this with a McLaren body.

Tjay
2008.05.13, 05:28 PM
If you're running mod class on your McLaren, I would think this should help it to understeer instead of spin outs/oversteer... good understeer on those hooking turns/sweepers. On a 94mm, I think it would give too much understeer. Just my opinion...

TALLGEESE
2008.05.13, 06:34 PM
It seems that if you run a narrower body with less wheel offset.. The effects of the swaybar in the front is less noticeable.. This would lead me to believe that the wider you go, the more you'll notice a change in the car.. At least that's what I feel is happening.. After reading through a couple of threads on here about the sway-bars. It seems that people either notice a big difference in handling or none at all... For me it seems to work, but then again that's just me...

EMU
2008.05.13, 10:55 PM
I am using them on my Mod class Porsche 962. I didnt notice much of a difference. Although, I did notice that the car is better planted. I am going to try softer front springs next race. I kept the yellow springs that I was using before I added the sway bar, but removed the preload shim and used shorter travel limiters than I had previously had.

The 102mm cars have lots of steering, even with 30d tires. So the sway bars should work very well at that wheelbase, although... I had to use thinner nuts, and shave down the top of the screws to clear the body. Also pinched my core transponder, and cut a trace, so I am going to need to get a new one.

Peregrinari
2008.05.14, 02:21 PM
Ok, my results thus far are as follows. I am running 3 degree rear 2.5 front with a Ferrari 575 GTC Body with RM setup. I am running Kyosho HG 30s in the front and PN 6s in the back. I started with the green bar and moved to the gold one. I found in the past that stability on the straights and coming in to turns was good but not what I felt should it should be. I installed the PN Bar and immediately found the car to be way more stable in the straights and planted entering the turns. Exit was even better as I can now power out of the turns without pushing nearly as much. Unlike most of you guys I am running the Atomic DPSII system as well. I knew this roll bar was going to be the perfect introduction to really dialing in the rear end of the car. What I found is that with the PN Bar and the soft Lexan H plate that I run, the rear would start to unload. The more I thought about why this was happening the more it seemed that that soft plate was not allowing the rear to stay planted and it would begin to twist and unload. The DPS II system to the rescue! I was able to run slightly harder springs on the side and rear dampers and suddenly the car drove entirely different. The rear wasn't unloading in the slightest. The diff was doing it's job again and I was able to push the throttle more through the turns. Mixing this with 30 weight Disk damper oil really smoothed things out.

So, what I take from this is that one needs to pay attention to the rear when installing this bar. The anti-roll characteristics of the bar keep the front end from rolling and unloading but as a result the rear needs to be a bit stiffer to compensate.

Overall, I really like this product! On my short test track I find that it is getting me closer and closer to the road holding abilities of the AWD which is something I like. I will see for sure this weekend if it has made a difference. Though I am running the AWD in the HFAY, I will get a chance to really test the MR02 while I am there. See you guys then!

Tom