Weighty subjects. FF03 parts.

To make this post make sense, we need to talk about USGT racing.  Lets start here: http://www.usvintagetransam.com/rules/USGTClassRules7-20-2017.pdf  The important bit of that PDF is the following quote:

Weight Specification: 4wd Minimum 1380g in race-ready trim Fwd no minimum weight

No.  Minimum.  Weight.  

Oh boy!  new parts.  A big pile of carbon reinforced parts.

So the FF03 chassis is soft, and flexy.  The springs are to hard.  And really, I was very displeased with my FF03 as it came out of the box.  $40 later, I had ordered all of the carbon or at least "hard" parts.  Most of them Tamiya claimed they were lighter.  I... well, mostly they weren't.   

Here's the evidence.

First, starting weight: 

The gearbox bridge:  3.5g  No savings.

Front suspension bridge: 2.2g savings

Main chassis: 5g savings

Moto brace: Gain .1g

Front bumper mount: 0.2 gram gain

Shock Pivot Top: 0.2g loss

Rear suspension pad: 0.6 gram gain

Rear suspension brace: 0.7g loss (times two..)

Rear suspension tower: 0.2 gram gain

Rear shock tower: 0.3 gram gain

And in the end, we have this:

Something like a 9 gram weight savings.  That... was not worth the effort.  For weight savings, at least.  The car is ~massively~ more stiff, so there is that. 

PS: as a side note, the suspension on the FF03 is mostly TB03/TRF418 stuff.  The knuckles, suspension arms, driveshafts and such, are all from the TRF crowd.  

Racing the Tamiya Team Hahn Euro Truck on CRC Black Carpet

First of all.  Here's Tamiya's rules: 2017 TCS Rules  Go to page 12 for the stuff on the trucks in specific.



Here we are, before my first race with my Euro Truck.  We're racing at Windy City RC. 

The Euro Trucks handle asphalt really well, as stock.  Things get all sorts of weird once you introduce high traction carpet, that's doped with traction compound.  So I thought I'd share what I've seen what makes these trucks work on Black CRC Carpet.

Suspension:

I've seen use of both the inside, and outside shock holes.  The fastest guys use completely oppisite setups, so I believe this may just be a "driving style" thing.  The fastest lap was turned by a truck with both springs "in" and the guy who won the main, had his out.  There's not enough data to draw conclusions on that. Yet.

Both people had "some goop" on the shocks.  I believe million weight diff oil.  Others are using Lucas Marine Grease.

The steering links can also be a little tight, and cause some binding and somewhat inconsistent steering.  It's to your advantage to waller them out a bit with a drill so that at the extends of steering and suspension travel you don't have any binding.

Weight:

The fastest lap time was turned by a truck with no weights on it.  The next fastest guy, who was running 20-30g, just enough to balance out the chassis left-right, and move the CG back a bit.

Body:

Almost everyone is doing "something" under the bodys to suck up the space between the body and the bumper.  Nothing seems consistent.  I don't believe this has any real effect on handling.

Transmission:

Everyone has "something" in the front diff.  Rear diffs are nearly, or completely open.  I was told to go with 1,000,000 weight up front, 10k in back, and that seems to have helped corner entry.  Keep in mind that the diffs are not sealed, and whatever you put in, will leak out eventually.

Tires:

This is where the answers are pretty consistent.  Everyone is running a whole lot of glue.  While it's typical to glue the outside of a tire, everyone is gluing both sides.  People who aren't tipping over, glue from rim to tread on the outside fronts, as a minimum.  I think I ended up with three layers of glue on my tires.  Everyone was running at least glue up tot the part line on the inside of the front tires.  In the rear, everyone was running something on the outside, usually to the part line, some to the tread.

Radio:

First, the steering servo arm boss is long enough to hit some servo bodies.  It needs trimming.  Do that or else your truck will have inconsistent left and right turning behavior.

Now, the radios, it's key to keep your steering to "just enough" so you don't tip over.  This can be difficult to set at first, as the trucks behavior changes somewhat between tiptoeing around the track, and a full speed run.  Going fast means having your steering limited to 60-80% of your full steering travel.  That percentage seems to change as traction some up, or goes down during the day.  This is a "travel", EPA, or DualRate, not expo or speed.

Driving:

The long and short of it is, 4 wheels on the ground, and commit.  These things tend to corner on three wheels, so before you punch the throttle again, get the rear wheel back on the ground, then go.  Getting on the gas before you have all 4 wheels down leads to some squirrely behavior.  (Swapping ends, fishtailing...)

Race to Race Prep:

Between races, the front tires get cleaned between rounds.  With a paper towel, and the usual r/c safe motor spray type stuff.  (Duratrax Magnum II at the local track...) The rear tires get some traction compound.

So that's what I've seen, and what I've learned.