F1 Long-term review: the fixes (part 3)

3) Steering consistency. Few things are more annoying than a wandering center. The Mini-Z F1 chassis has a great servo saver, but it could use some work. If you notice any sticking, give it a good polish and lube on the mating surfaces. The big e-clip at the end can also hang up a little on the inside of the top cover. I like to sand down the edges and the overall diameter to ensure that nothing binds. Finally, if nothing seems to be working, try a new one. Servo savers can wear out or just be bad.

If you've raced F1 for a while, you've broken a plastic tie rod. This isn't the servo saver's fault, as the wheel is actually being ripped past the travel stop. The servo saver does it's job and saves the gears, but the tie rod or knuckle often can't take the load. You've got to use aluminum tie rod and knuckles. I like the 3Racing tie rods since they have a smooth finish. The old Kyosho aluminum knuckles were the best, but they've been discontinued and replaced by the R246 versions with the brake disks. These are essentially the same as the 3Racing aluminum knuckles, so you might want to give those a try. Camber plays a role here and less tends to give you more turn in.

Now if you've ever tried to install an aluminum tie rod, chances are you've broken those little tabs on the chassis. Don't bother replacing them with an aluminum holder, none of them work particularly well. I've spent time filing and sanding, and they all stick. While I've run with the tabs broken, I like stabilizing the tie rod a little more. The trick is to just go ahead and trim the front of the tabs, so you can slip the aluminum tie rod in, but they still support the tie rod from underneath. This keeps the tie rod operating on an even plane, so that the knuckle pins have a good contact surface. Aluminum on aluminum can bind once dirty, so a little lube here keeps the steering nice and smooth.

Another random tip I learned was to "screw" the front springs into the knuckles. The knuckles on the F1 have very tight tolerances for the springs, and I have chased setup for a while with one spring not seated all the way in the knuckle, essentially preloading one corner. Speaking of preload, make sure you've got enough preload on the springs to prevent the front bumper or wing from dragging. I do a lot of work filing the bumper mounting points to bring it up to the wing, but even the wing level can drag at times as the weight transfers forward on entry. If you are getting an initial push, chances are you are dragging something in the front.

F1 Long-term review: the fixes (part 2)

2) Tires, tires, tires. An old adage in racing of all scales is that tires are 90% of your setup. At a big race at an unfamiliar track, we talk about "hitting the tire setup". The challenge is to predict the best tire combo which changes throughout the race weekend. The "best" tire combo is one that provides the most overall grip while offering a balance that suits the motor and your driving style. This balance can be additionally tuned with dual rate, but you don't want to stray too far as steering angle has other repercussions.

You know the track will change, so there's no use in freaking out about overall grip. At the same time you can't afford to compromise practice or qualifying with an unbalanced car. What a lot of newer drivers don't realize is that low traction usually makes a car push, not oversteer (especially on entry). The exception is a motor with a lot of power or an abrupt powerband that can overwhelm the rear tires on exit. I start with as much rear grip as possible and a pretty aggressive front tire. The front tires gradually shift to harder compounds and less steering as the traction and front bite comes up over the weekend. Experiment with different brands, compounds, carpet tires and truing to develop a spectrum of front grip you can use accurately dial in the balance.

At the worlds, I completely screwed over my teammate Matt in the main with a bad call on rear tires. Due to the aforementioned packaging issues, I had been struggling with grip the whole week and took a last chance gamble with trued PN8's over Kyosho 20 rears. The grip was improved on a few trial laps, so I recommended it to the rest of my team. What I hadn't accounted for was the chemical grip fade of the PN8's. Less than halfway through the main, the rear grip disappeared and Matt and I were left with a couple really ill-handling F1's.

Luckily, Eugene and Jacob stuck with consistency of the K20's. Later on, I tried the same trued PN8's back-to-back against worn K20's, and it was like night and day. There was no physical indication of wear on the PN8's, but the grip was gone. The truing probably didn't help. The lesson learned is to understand your tires, how they wear, and when they will let go. The PN8's might just be the hot ticket when new, and I need to study how many runs I can get from them without relying on physical wear indicators.

Additionally, you MUST use R246 tape with these tires. There is just too much squirm in the center that leads to unpredictability. We also superglue the tire with mod motors for even more consistent traction.

F1 Long-term review: the fixes

1) Packaging. What does packaging have to do with racing? Everything, especially in F1. Packaging engineering is one of the most important and difficult parts in designing an F1 car and this translates to Mini-Z. It's the proverbial conundrum of fitting 10lbs of stuff into a 5lb bag. Whereas the bulk of a full-scale F1 car is limited by aerodynamics, Mini-Z F1 is constrained by scale appearance and rightly so. The rear suspension of an F1 is a challenge, trying to cram as much suspension underneath that gorgeous scale body without anything hitting. Some bodies offer more room than others, and the latest models have enough room for a top spring and disk damper setup with some internal clearancing.

In that quest for an effective low profile rear suspension, I selected the 3Racing disk damper (same as upcoming R246). The problem that I couldn't identify until recently was that the lower disk damper translated to a lower damper arm on the motor mount. Both the Atomic motor mount and the 3Racing motor mount allow you to run the damper arm low enough to hit the rear battery when the suspension compresses under acceleration. The top spring damper mount on the PN motor mount is not adjustable and doesn't hit, but it can't readily accept a disk damper.

There are a few ways to check if you are running your damper arm too low. The easiest way to check is to inspect the area from underneath the battery box while working the suspension. If the damper arm looks like it's intruding into the battery box area, you're too low. Another way to check is to install the batteries, but leave the battery door off. If the rear battery pops out a little when compressing the suspension, then you're too low. With the battery door on, the damper post/top spring will abruptly move up instead of forward when compressing the suspension if the damper arm hits the rear battery, i.e. - you're too low. Finally, if you're noticing weird chunks missing from the center of the battery insulation after a big wreck, you're too low.

The net effect of this is that you will have no rear suspension compliance under acceleration, which is why I couldn't put any power down at the worlds. The deceptive part is that the suspension looks like it's working, aside from the strange upward movement replacing the forward movement when the damper arm hits the battery. This effectively turns the bottom disk damper spring from a disk tensioner to a rear suspension spring, if the suspension can even get past the initial shock of hitting the battery. I fixed the issue by installing 1mm spacers underneath the disk damper plate, raising the whole assembly and the damper arm once the disks/post were centered. 1mm fixed the rear end... I'll pause to let that sink in. A side benefit is that motor wire clearance is improved. Drawback is that you have to clearance the underside of the body for the higher screw heads, top disk and rear top spring damper end.

Speaking of top spring dampers, I currently use the PN side damper for this application because it's a good length, has screw preload, and lots of options for spring rates. I like the PN white spring. You have to aggressively file the sides of the rear damper end and clearance the inside of the body cowl to give enough roll travel, but I think it's worth it. Additionally, don't short yourself on rear ride height with the top spring preload or the axle spacers trying to dump the car. RCP is bumpy, and dragging hard parts will lead to inconsistent handling. I also like to sand down the rear corners of the battery door to points to give more squat clearance during cornering.

So now that we can accelerate, let's look at cornering and roll stiffness. I'm going to go against the grain, and say that the rear end doesn't need to be MR floppy for mod. The F1 is a heavier chassis, and I think that the roll stiffness of a side plate setup is more than compliant enough to handle the power with a couple of tricks. Old school tuning left various side plate screws loose. This WILL NOT WORK with grey chassis, as for some reason the screws do not grip the grey plastic as well as the clear plastic and will back out unless tight. I personally have moved away from this, since the side plates are the only thing that "locates" the motor mount and thus the rear axle and wheels in relation to rest of the chassis. Leaving them loose has led to inconsistent handling as the car struggles to stay "square".

I've got quite a few options in my pit box for dialing in the rear roll stiffness. Side plates include Kyosho carbon, Kyosho carbon thinned down to 60% width, and Mantis carbon in order of decreasing stiffness. In addition, I use the full plastic spacers/blocks that come with the Kyosho carbon side plates for full stiffness, but I have beveled versions of both front and rear blocks that I can use in different combinations to soften up the side plates by increasing the effective plate length (moving up the pivot point with the beveled front block), or relieving the rear tension on the plate with the beveled rear block (so it bends in more of a "C" shape than an "S" shape). If you don't believe these have an effect, you will if you install a beveled block on one side and a full block on the other… Side springs can also be employed, and I've cut the "tubes" out of an old plastic motor mount so that I can screw them onto the Atomic motor mount. The 3Racing and PN motor mounts have the tubes machined in. Using the side springs will also let you use the Kyosho tube dampers.

Other things to look out for with side plates include the dreaded tweak. While the grey chassis has addressed the molded tweak issues of the clear chassis, the Kyosho carbon side plates also have a slight tweak that you need to address. The Kyosho side plates are made identically left and right which means that any bend in the raw material will be in the opposite direction when mounted on opposite sides of the car. Most of the Kyosho carbon side plates I've seen have a slight upward bend when mounted on the left which means a slight downward bend on the right. This means a stiffer right side which leads to the infamous left tweak. A thin shim between the side plate and the motor mount will usually address this without having oddball steering bias in the radio that can have inconsistent side effects. The Kyosho side plates I thinned down don't seem to exhibit this tweak which means that they are just too soft or I wasn't perfectly even with my sanding. The Mantis side plates are made individually left and right, so they aren't tweaked, though the holes can elongate. With an aluminum motor mount, it's also cheap insurance to use a nut in addition to loctite to capture the rear side plate screw.

Motor Mount Pre-Orders

Reflex Racing Club Series!!!

We are so excited to get the ball rolling. Check out the exclusive page to the series to find out what it is all about. We want to get as many sponsors and participants as we can in order to expand Mini-Z Racing globally. REFLEX RACING CLUB SERIES

Cristian's MR-03 at the Worlds

Brief post, cause it's late... :P This was my car at the Worlds. It was fantastic. It allowed me to finish 3rd Overall in GT Mod amidst some very stiff competition and without having driven a Mini-Z since June. It had prototype parts on it as well as some other parts that I had personally not run on an MR-03. One of them was the Low Profile Suspension. I LIKE IT A LOT! Come to think of it, our results seem even better when we put the conditions into perspective. In every class, we had the Top Finishing MR-03's as well.

My set-up was simple:
Front:
-Silver Low Profile Springs
-4 Degrees of Caster
-Low Down Knuckles 0.3 shim underneath/ 0.5 above knuckle (below ball)/ 0.3 shim at the top to give slight Pre-Load
-30000 Wt Kyosho grease on the lower ball (where the spring insets)
-1 Degree Camber
-PN RXF 15 Tires, on 20mm Wheels, trued to 23mm on +2 Wheels

Rear:
-Reflex Soft MM T Bar
-96mm Position on Motor Mount
-Silver Side Springs on Tri Shock, 15000 wt Grease
-450 CST oil inside Kyosho Oil Shock, 50% Rebound
-Kyosho Yellow Spring, Pre Load set to have chassis level when fully loaded
-PN Racing 6 Degree Slicks, Trued Flat. +3 Rear 20mm Wheel
-Atomic Diffusor Installed

Power:
-CTP Tuned 32 Turn PN Spec Motor
-Atomic VP 800 Batteries
-Gear 11/53

WINGS!!!

Pictures, 'nuff said!

Low Profile Front Suspension Set-Up

Hi guys! Check out the pics!!! This is a little project that we kept kind of hush until we really knew it would work. Basically what it is, it is a 12th scale pan car-style front suspension spring set. The Springs are small units that were designed to fit inside the lower pivot ball of your MR-03 Front End. In order to make it PN Racing Front Lower-Arm compatible, we made the lower ball narrower. So this way, you can have a reverse-king pin set-up and you can also run 4 degrees of caster with our front end!!!

These parts were not really designed to replace our extra-long King Pin Set-up, but rather they are an option, in case you want to run reverse-type king pins. WE ARE STILL PRODUCING THE EXTRA LONG KING PINS AND ANCILLARY PARTS.

This new front end requires you to run some pretty small diameter front tires so that the front does not sit too high and it is also a bit harder to adjust. You just can't add washers on the fly to set pre-load. Up Travel is also not really adjustable, but with the coils compressing quicker, the suspension travel is less than with the Extra Long King-Pin Set-Up.

This set-up works really well and reduces the slop in the front end even further. There are limitations related to ride-height in the front and it is a bit of a pita to change the front springs in order to adjust properly, but when tuned right it can offer more precise handling (due to the reduced slop), and it is lighter in weight. It will be offered as a complete package: King Pins, 4 delrin Balls, E-clips (with a couple of spares) and a soft/med/hard spring set. it should sell for around 14 bucks!!!

If you are concerned about the bottom hitting, don't worry, the bottom of the kingpin is at the same position as the bottom of the reverse King Pin PN Racing set-up!!!

Reflex flight 910 preparing for takeoff...

Check back tomorrow for updates!

Yes, really tomorrow. I already have the pics... :p

updated 9/1/10. more tomorrow...

updated 9/2/10. every day, new pics...

updated 9/3/10. F430 fitment...

updated 9/4/10. McLaren F1 fitment...

updated 9/5/10. SC430 fitment...

updated 9/6/10. DB9R fitment...

updated 9/7/10. NSX GT fitment...

updated 9/8/10. I was going to take pics for 350Z fitment, but I the original mold is being replicated...

updated 9/9/10. Hope to have images of the production molds tomorrow...

updated 9/10/10. So flight 910 is a little delayed getting out of the gate, but I dropped off the lexan today at our production shop. Production molds will be done early next week, and we should have production units ready for sale the week after! Stay tuned!

updated 9/16/10. First samples off mold!!! WOOT!

updated 9/21/10. We danced back, and now IT'S ON!

Our Tri-Shock

Pictures right now, It's late and I'm real tired... I'll elaborate soon!

The Future is Here ;)

With the arrival of the MR-03, the development of this platform has rapidly changed the world of Mini-Z. These machines are now more precise, easier to drive, handle more power and are overall better cars.

The latest incarnation of my personal set-up led to the development of a lighter tri-shock suspension with proper suspension angles. The tri shock allows for easier tweak adjustments (so the car turns equally left to right) and provides better acceleration. Note that our tri-shock set-up uses ONLY the side shocks and a center shock. When using this suspension with disk dampers, the car becomes over dampened, and the advantages of having independent side to side and fore and aft suspension are eliminated.

Below we also have the adjustable upper arm mount. This is truly a revolution. It is designe to be used with any suspension type and/or upper arms, but it works best with our king pin set-up because we can incorporate proper caster angles. 0-2 degrees of caster is really inadecuate for onroad cars. The happy point lies somewhere between 3 and 6 degrees, many times up to 8. This is why all larger scale 2WD race cars use this much. YOU WILL NEVER SEE A CAR RUNNING 0 DEGREES, and very little, if any, less than 4. Another advantage is working with your roll centers. I wrote a whole article about this before, but with a front upper arm mount, you can adjust the roll center in my favorite way, by raising the inner pivot of the A-Arms. Lastly, you can adjust your camber angle so your tires wear evenly under all kinds of different track conditions.

The last thing that is amazing is the weight of the cars. I have had to add about 6 grams of balast to the bottom of the chassis to get to a racing weight of 175.8 grams. This is with a FULLY HOPPED-UP Car, WITH A FRONT BUMPER ON IT!!! This was unheard of with the MR-02's. Balasting is a good thing though, it allows you to play around with the weight of the car and locate it in the most effective spots for your car balance to be as close to perfection as is possible.

Hope you enjoy the pictures! CT

Reflex Racing Special Project: the little Mini that could...

1/14/09

PN says: Do you plan to go to KO race in March?

Joe says: Yup

PN says: Maybe I will build a 90mm AWD for the Mini Sport Class

Joe says: AWD 90mm?

PN says: KO race will have a Mini Sport Class for 90mm cars only

Joe says: Ah awesome! I should do that too

PN says: 2WD or AWD? They are running them together

Joe says: I have a Mini Cooper MR-02 right now

Joe says: Turns so quick, but traction rolls

Joe says: I need to try and fit a sway bar on it

PN says: Yes maybe you need a harder front tire

Joe says: I think I’ve got 25’s on it!

PN says: You should try 30. Or stock tire

Joe says: Yah I guess so

blahblahblah...

And that's how it started.

We all knew that Philip would never leave his beloved MR-02 chassis for the AWD...

Missing my old 1:1, I had built up a Mini Cooper MR-02 using PN narrow front end just to goof around with.

2/25/09

PN says: 90mm motor mount sample is here

PN says: I just assembled it. Sooooooooooo sweet

PN says: I can’t wait to try

Joe says: *&$% it! Send me a pic

Joe says: Maybe I’ll try to sneak out of work to pick it up.

And just like that, the PN 90mm MM MR-02 motor mount was born. I couldn't sneak out of the office in time to pick up the test sample, so I had Philip send it to me. I rebuilt my 2WD Stock MR-02 with all the new Mini chassis components just in time to MISS the last day that Kenon would ever be open. For some reason, I didn't understand what Philip meant by "I'm closing the track today." I just thought, "Yeah I know. I'll try to stop back by tomorrow for some testing..."

3/2/09

PN says: I tested the motor mount today. The setup is GOOD!

PN says: I beat Chad in stock class at last Friday

Joe says: hahahaha

Joe says: awesome

Joe says: what spring

Joe says: are you running wide tires?

PN says: on my track, front yellow

PN says: F40 body

PN says: yes

PN says: 1 front, 0 rear

Joe says: yah i'm going to run mini cooper

PN says: another choice is AE86

PN says: also very good and stable

Joe says: yah

PN says: when i put on the F40, sooooooooooooo good

PN says: huge difference

PN says: wide rear tire

PN says: i also used an F1 shock on top, much better

Joe says: interesting

Joe says: i never liked the f1 shock

Joe says: prefer the oil shock

Joe says: but may be too high for this setup

PN Philip says: oil shock is too big, try the f1

PN Philip says: i can set you up

Joe says: i don't care i'm still running mini cooper

Joe says: will be fun

Sure I had committed to running the Mini Cooper body, but I still had a few tricks up my sleeve. I decided to abandon the front swaybar attempt since there was just no room in the chassis for any of the conventional setups. First thing I did was lighten up the body. The "sunroof" mod is popular with racers, and remains legal in most classes. It usually results in a few 0.1g from the top of the car. The funny thing about the mini cooper body is that the roof is only glued to the windows and has no other attachment points to the body. This makes it very easy to remove and thin out with a dremel and wire brush attachment. I would be running an MR-02 chassis with the PN MR-0175 tower bars to reduce the roll with this already tippy setup.

The other big upgrade would be the rear wheels and tires. I've experimented with semi-wide (9.5mm) rear tires in stock class before with some success. I find that in certain traction/temperature situations, they work as well as full wide rear tires. I had some sample semi-wide SSG's laying around, and I knew that these would be just the ticket. The standard 8.5mm narrow wheel/tire setup leaves room in the Mini Cooper wheelwell, so I knew we had some space to play with. Simple math said that 9.5mm semi-wide tires on a -1mm offset semi-wide wheels would give me the same rear track width as the standard 8.5mm narrow setup.

So where do you get -1mm semi-wide wheels? You make them! Starting with Atomic -1mm wide wheels, I carefully sanded them down to the correct width and glued up the semi-wide SSGs. Why all this trouble for wider wheels and tires? Well first of all, we would be running PN 70T stock motors which have more than enough grunt with race batteries to overpower narrow rear tires. The smaller contact patch of narrow rear tires not only affects the power application, but the consistency of the handling via squirm. I thought that a narrow aspect ratio (unless trued WAY down) might squirm badly under the combination of acceleration and cornering loads on exit. At this point, I hadn't figured out whether the chatter/traction rolling in my previous setup was generated from the front or the rear of the chassis. I suspected a little bit of both - sometimes the nose would tuck in corner entry, sometimes the rear would hop around on exit. I hoped that the semi-wide rear tires would give me a more consistent and stable rear contact patch to apply power during corner exit and solve 1/2 of the problem.

Just for good measure I also sanded some Atomic +1 narrow wheels down to 8mm width for use in the front. With camber, they had no issues rubbing, and I thought they might help in the front end stability department...

Took the new setup + a few options out to OC/RC to shake her down. Better than before (due to the damper plate system), but I was STILL traction rolling when the tires got up to temperature and if I started pushing it. I tried going stiffer on the suspension, damping, etc. to control the oscillation, but no help. The car did feel very consistent when I backed the pace off to 80%, and the thing could turn on a DIME. It was very interesting being able to run so deep into a corner, stay wide, turn in late and not wash out and blow the apex. On top of that, the car could actually tighten the line on exit under power. This would come in handy a little later...

Race Day!

After a long drive up to NorCal, we got set up in the mall area. This was my first mall race and Binh and the Inside Line crew really put together an awesome venue! There was an escalator leading to the second floor where spectators could gather for a bird’s eye view of the racing action below. Practice was VERY crowded with a line 20-30 racers long waiting to get their shot on track in timed intervals. I knew my F1 car was fine, and I really wasn’t that concerned about Stock 2WD, so I focused on the Mini. As usual the track started off very green and slippery which brought the push out of most cars.

Some of you may wonder what those stupid pink flowers are all about. I always like to grab a random memento at each big race. In our rush, I hadn’t packed a pit towel or napkins or anything to wipe down the tires after gluing. We happened to be pitted next to this plastic flower bush, and the mall kindly “donated” some flowers so I could wipe the excess CA off the sidewalls (critical on the Mini fronts). I found the flowers in my pitbox a week later and there you have it.

I started out with semi-wide SSG’s on the rear with -1 offset Atomic wheels that I had shaved down. They provided plenty of forward traction, but I was struggling with finding the correct front tire for balance. I tried a variety of different tires from sticky to hard, and fiddled with the dual rate to dial in the steering. As the grip came up, traction rolling started rearing its ugly head. I ended up having to lift before the sweeper and bend it in to prevent the little Mini from flipping off the track. I miscalculated this more than a few times resulting in some pretty spectacular crashes much to the delight of the crowd that had gathered above. Lots of oohs and aahs and groans from the onlookers didn’t do a lot for my confidence. It felt like everyone in the mall was watching my little red cannonball careen off the track…

Come the qualifiers I really focused on blocking out the crowd and getting some solid conservative runs in. I managed to save a few of the traction rolls with some rather entertaining bicycles in the sweeper and the infield. This brought a smile to my face, and I really started having fun. I ended up qualifying at the rear of the grid in 9th, but I was confident that if I could keep it on all 4, I could fight my way into the top 5 for the main. I was the ONLY Mini Cooper in the field surrounded by F40’s, RX-7s, and other low slung coupes. While the top-heavy Mini had its issues, I was able to turn under just about anyone on exit, as long as the car didn’t end up on its lid.

For the main, I rolled the dice and tried a trued PN 20 degree front tire – stickier than I had been running in qualifying. I dropped my dual rate down and tested the front into the sweeper on the warm up laps. My hunch had paid off! Reducing the steering angle had all but eliminated the traction rolling! It wouldn’t hold up to a Scandinavian flick, but I could finally bend the little Mini into the sweeper at speed. I still had plenty of steering in the infield, and the reduced steering scrub had totally freed up the car for some pretty amazing corner speed.

When the horn sounded, I rolled into the throttle anticipating a pile up in the first corner. Looking for a gap, I ended up getting knocked backwards by a more enthusiastic driver, so I had a lot of work to do. In dead last, I settled down and just tried to nail the same line lap after lap while adjusting to the new steering characteristic. A few laps into the race, the tires came up to full temperature, and I finally got a feel for what I could get away in each corner. By that time I had started reeling in the other drivers. This is where it got exciting. I would pressure for a few corners, wait for a little mistake and duck right underneath. It felt like I was passing someone almost every other lap. When I came up on another driver coming onto the straightaway, I took an outside line in the sweeper just to be safe. Imagine my surprise when the little Mini slingshotted the long way around and completed the pass going into turn 1! The car was so on edge, but if I did my part, I could put it anywhere on the track. Given my tendency as a race announcer, I started providing my own color commentary from the drivers stand infused with plenty of laughter and disbelief as the Mini clawed it’s way through the field.

Being lost so deep in the field, the announcer hadn’t noticed my rise through the running order, but the cheers of the crowd above and my fellow racers in the pits brought to light that I was now sitting in 3rd place! I was stalking 2nd place who was running an excellent tight line. I got the drive coming out of turn 1 and the earlier outside pass in the sweeper made me think I could at least stay on the high line into the tight infield. I was as surprised as anyone when the little Mini carved a beautiful line around the outside and ahead into the chicane. From there, I pulled away in to a solid 2nd position. Up in front Philip’s F40 was gone. His car was turning almost the same laptimes as Stock 2WD. While I couldn’t manage to track down the win, I had just driven one of the best races of my life, grinning and laughing the whole way to 2nd place. From the cheers in the crowd and the celebration in the pits afterward, it felt like a win.

I can’t lie and say that the Mini never traction rolled during the main. I got a little aggressive on the exit of turn 2 and managed to tumble into the chicane, beaching the Mini on the rail. The car was literally high centered in the worst spot on the track for a marshal to get to. My buddy Emu had run into some mechanical trouble with his F40 (which was also ballistically fast), so he was laps down on the field. He had just come around the sweeper when he saw where my car was, rounded turn 2, made a beeline for me in the chicane and plowed full throttle into the rail I was on top of. The result? He could have broken my t-plate. He could have bent my axle. He could have broken his car. He could have flipped me on my lid. None of those things happened. The impact popped the little Mini off the rail onto the other side, landing on its wheels and I was back on course costing only a couple seconds for my mistake! A completely intentional, unselfish gamble by Emu had easily saved me a lap so I could continue mowing down the field. To this day, I still can’t figure out how he managed to spot my car, recognize it, weigh the risks of his track position and mine, formulate his harebrained scheme, and execute it against all instincts (it’s completely unnatural to intentionally drive straight into a rail) – all in about 1 second. It’s things like that that you never forget. Even at a toy car race.

PNWC SoCal Qualifier 6/5/10

I had a rough return to racing this weekend after sitting it out for over a year. I was driving Cristian's old stock MR-03, and it felt pretty darned good. This is a different Kenon track and the grip is really inconsistent with a mix of tiles (age, condition, and height). There are lots of seams that can grab you midcorner, and the surface is really abrasive. I tried a few things here and there, some worked and some didn't. The grip improved over the weekend and the search for front tires was on. I never really hit the tire setup, and just tried to tune it from the rear.

I followed my race plan of running a conservative qualifier and turning it up for round 2 and 3. I got quicker every round, but always felt a couple tenths slower than in Friday practice. In the main, I found out why. My motor let go at around the halfway mark. It had been going south the whole race. I had been running one of Cristian's supertuned motors in practice and it was smooth and punchy at the same time. The handout just felt softer and softer, which affects timing rhythm etc. In the end it just came to a stop, and I pulled off worried I might blow a FET. I've seen this happen to my teammates, but I've always had good luck with handout 70T motors. I guess it was just my turn to get a dud.

In any case, I feel pretty rejuvenated. I wasn't really in the hunt, but just getting warmed up felt good. It was nice to see old and new faces at the track, but I need more practice and experience with tires so I can make good calls come race day instead of just guessing. Will hit it hard over the next few months and see you guys at the Worlds!

Long-term Review: F1: Part 1: Shakedown

Started testing tonight with the Carbon Limited Edition F1. I ran it box stock at Kenon tonight to get an impression of any improvements over the bone stock original.

Initial reports are mixed. I'll get more in depth later, but here are a quick 20 questions.

1) Is it better than the bone stock car? Yes.

2) Is that because of the upgrade parts? No.

3) Does the car come tweaked like the clear chassis sometimes would? No.

4) Is the grey chassis stiffer? Yes.

5) Does it drive differently? Yes.

6) Is the grey bumper stronger than the clear one? Yes.

7) Does the grey bumper have good ground clearance without modifications? Yes.

8) Is it the bumper I would race with? No.

9) Do the plastic knuckles still stick with the stainless kingpins? Yes.

10) Is the plate damper system good? Yes.

11) Is it enough to plant the rear end? No.

12) Am I happy with the upgrades that came on the car? Yes.

13) Am I happy with the way the car drives out of the box? No.

14) Is the car competitive out of the box? No.

15) Am I disappointed? No.

16) Am I planning on modifying the car? Yes.

17) Am I planning on adding upgrade parts to the car? Yes.

18) Will they be expensive? No.

19) Is this car the best way toward a competitive F1? Yes.

20) Will Crotty beat me this year with a near-bone-stock car? Man, I hope not... :d

All in all, it was a frustrating but valuable test session. The car needs some lovin. I'm tempted to just throw my old setup on it and be happy, but I know that the competition has definitely caught up in the last year or so. That plus the transition to mod motors means it's time for a clean sheet approach.

-jc

Roll Centers on the MR-03

Well, it's been almost a month since my last post. I promised set-ups from the Tekin Race, but I just was not satisfied with them after I ran my car at the local track. The ILR track is funky and the grip is weird, so set-ups from there are very different from anywhere else I run at. I have edited the previous post with my old set-ups.

This post though, is about moving forward and fine tuning the new MR-03 front parts, that are getting rave reviews from customers all over the world.

Let me give you a run-down of what has happened at the track since the Tekin Race:

Last week, I raced for the first time at my local track with the new parts. Grip was a bit different, and everyone was running a bit slower than usual at the track (especially me). My car was about 2 tenths slower on fast lap from what I had done the previous time, but so was everyone else. Marcus (Mantis) was the only one that was going a bit quicker than before, but he was just starting to get his 03 figured out. Still I was the quickest in qualifying by about a lap over Jacob, but the consistency was not there.

In the first qual, I ran a 96mm set-up, while it was super easy to drive, I was not able to go any faster than a 7.36, which was about 2 tenths off of my quickest previous lap. Marcus actually ended up with the quickest lap with a 8.31 and Jacob had like an 8.4 or 8.5, so I knew I needed to pick up the pace.

For the second qual, I went back to 94mm and the F430. I instantly picked up a tenth and re-set fast lap at 7.22, but the car was not there yet. Consistency lacked, due to the fact that the car lacked rear grip. I was running the medium 94 FRP plate, so for the 3rd qual I went to the soft one. With the soft one I gained the rear grip I was looking for, but I also gained a lot of turn in, so the car became real nervous. I was running white low down springs, and they seemed a bit too soft. My feeling was right, as I traction rolled my 03 for the very first time ever in the carousel at the end of the straight.

So for the main, I went with yellows, the car became much more balanced, and much easier to drive. I was able to push down my fast lap to a 7.16, which was essentially the fastest I had run during a race. The only problem was that the dreaded traction roll had come back! :o This traction roll cost me nearly a lap and I even lost the lead for about half of the race to Jacob. I also had to drive conservatively at the end of the straight to prevent the car from rolling off the track again. In the end, I still took the win by like 5 or 6 seconds, but I knew that the traction rolling was a big issue that I had to deal with.

Having that in mind, I went home and I stared at the car for a while. I knew the problem was with the front end. At the moment I had lowered the front by putting 3 shims underneath the knuckle. This created an extreme angle with the upper arm which creates a really low roll center, which I was guessing was the culprit to my troubles. Whenever you have an angle that steep, you make the front act very soft and the only thing you can do is add a stiffer spring to fix this. I don't like runnign very stiff springs on my cars though, because I feel like it does not absorb imperfections as well.

I had a couple of options to raise the roll center. The first was running a smaller diameter front tire. This can be achieved with either a really small tire, or the smaller Mantis front wheels, or the combination of both. The problem, is that I hate to have to true down my tires too much and this is a waste of rubber. By running a smaller diameter front wheel and or tire, the front sits lower, so I can take some of the knuckle shims out.

The other option was the one that I actually went with. This was installing the PN Lowering knuckles for the 03. By raising the axle 1mm up, the car achieves a higher roll center, while keeping the ride height lower and the upper arm angle pretty much parallel to the ground. This achieves a little bit higher roll stiffness (think in between spring rates) with each spring. So now, the PN whites would actually work as a little bit stiffer spring. More importantly, the roll center being a bit higher, the car would not want to roll as violently in the corners, which in theory I thought, should eliminate my traction rolling.

Well, fast forward to tonight. Tonight was not looking like we were going to race. We had a very small turnout, so I had set my mind at working on my car's set-up. I wanted to test to see if my theory on racing the roll center would make a difference and I also wanted to try a couple of different bodies.

From the first run on the track with my Stock car was pretty good. The car was balanced, but a bit loose, this led me to bring the car into the pits where I experimented a little with lube on my DDS and the front knuckles. I found that a good combo was Kyosho 5000wt in the front and Atomic 500wt on the DDS, this gave me a car that was fairly aggressive and very planted. At the time I was running PN White springs in the front and I had the chassis slightly lower in the front than in the rear. After trying different pre-load combinations and springs, I found that this was the best and quickest setting, so I did not mess with it any more. It is important to note that the MR-03 is very sensitive to ride height and suspension stroke (how much the suspension compresses) adjustments, so don't be afraid to try them out!

In the spirit of experimentation I tried the Lexus SC430 body on my car. This is the body I won the World Cup in '07 with and also a very popular choice out with the Norcal guys. Instantly, the car felt really good. The grip was very neutral and the car seemed easier to drive than with the F430, remaining flatter through the corners and acting a little bit less aggressive. I really liked the body. Soon after, we all decided that it might be a good idea to run a couple of qualifiers and a main.

At the start of the first qualifier I jumped into the lead. I was able to stretch it out fairly well, the car felt good, but for somereason, I was not able to go any faster than a 7.2 second lap. Given that my fastest lap was a 7.16, it was not far off base, but I felt like the car had more to give.

After the run, I went into the pits and switched back over to the F430GT. Typically the F430 generates a bit more grip and it allows me to hug corners a little bit better than the SC430. The SC430 feels smoother and faster, but what came to light, was certainly enlightening. From the beginning of the run I started dropping consisten 7.1's and 7.2's, whereas before it was 7.3's. On lap like 10, I dropped a 7.03, a couple of laps later, a 7.06! This was what I knew the car was capable of doing. The scariest part was that it was a less powerful battery pack than what I had saved up for the main. Coming off the track Marcus even said "I guess that body works better!" I agreed...

Right before the main, I put the car on the track and took it for a lap. The car was a ROCKET!!! I thought for sure I was going to crack a 6.9 second lap. Off the start I jumped out into the lead and started getting into the groove. Unfortunately some sort of debris got into the commutator of the car and the car slowed down severely. It even left a little smoke trail going around the track, looked almost like a real car blowing an engine. Whatever it was, if burned off quickly though and the car got back up to about 85-90% of the speed it was going to. I knew this was not going to be enough power to do a 6.9, but I thought maybe I could do a 7 flat if I worked hard. Honestly, the 7.0 was probably a little bit of a stretch with how slow the car was, but somehow, I still managed to get 7.13. After the 10 minute main was over, I realized I had just shattered the previous stock class record of 80 laps in 10:06, not only that, but the Modified track record of 81 laps in 10:06 had also gone down, since I had ended up with 81 laps in 10:04. If I had only had a better motor, I know an extra lap would not have been out of question either...

After the dust settled I was really happy. This was the 3rd track day with the new Reflex MR-03 parts and I am still finding tenths of a second each time out! That to me, is VERY exciting. There is nothing like going faster than before after installing your very own option parts. Specially because the dreaded traction roll never made an appearance during the whole night.


THE SET UP:

Front:
-Reflex Extra Long King Pins and Delrin Balls
-PN Racing Lowdown White Springs
-PN Racing Lowdown Knuckles- 0.3mm shim underneath
-Spring Pre-load neutral (no slack when off the ground)
-4mm Spring Cup
-0 offset wheels
-Kyosho 30 slick, trued to a flat carcass
-Kyosho 5000wt grease on kingpin
-0 degree toe rod

Rear
-Reflex 94mm G10 Soft Plate
-PN 70 turn stock
-51/12 gear ratio
-Kyosho F1 Shock with greenspring
-Atomic 500wt oil on DDS
-Axle at 2nd highest ride height pos. On PN 94-98 Mount
-Kyosho 30 deg Rear Radial, tread gone
-Atomic Green DDS sprigns
-+1 Rear Offset Wheel
-QteQ Rear Diff Parts


Body: Ferrari F430
Battery: R1 Wurks 750