A FF03 for USGT - Bending the rules, cheaply.
#1
Howdy Everyone.
Regardless of my driving skill, I still am always looking for the advantage. USGT has a "no minimum weight" rule for FWD cars. I'd regularly troll TamiyaUSA's website for the cheap cars. The FF03 with the CR-Z body was up for $100.
...Don't mind if I do...

So this is where we start. I tossed the stock springs, and threw on ones that "seemed like they worked". The stock springs were so stiff, that there was no appreciable suspension movement. As the car sits there, it's 861g. 971g with the factory wheels.
The car is going to do most of it's work on black carpet. The car, to be competitive, is going to need to find some way of overcoming the lack of rear drive wheels. I can only think top seed, and corner speed will be able to do that.
When I built the car, I omitted a lot of parts. No radio tray, no servo guard, no battery retention, and a bunch of other bits. The car also came with plastic shocks, the weak servo saver, and some pretty trashy wheels.
We'll cover the the real weight reduction attempts in the next post.
... did you know, that before I started this thread, I've only started 22 threads since 2010? *shakes head*
Regardless of my driving skill, I still am always looking for the advantage. USGT has a "no minimum weight" rule for FWD cars. I'd regularly troll TamiyaUSA's website for the cheap cars. The FF03 with the CR-Z body was up for $100.
...Don't mind if I do...

So this is where we start. I tossed the stock springs, and threw on ones that "seemed like they worked". The stock springs were so stiff, that there was no appreciable suspension movement. As the car sits there, it's 861g. 971g with the factory wheels.
The car is going to do most of it's work on black carpet. The car, to be competitive, is going to need to find some way of overcoming the lack of rear drive wheels. I can only think top seed, and corner speed will be able to do that.
When I built the car, I omitted a lot of parts. No radio tray, no servo guard, no battery retention, and a bunch of other bits. The car also came with plastic shocks, the weak servo saver, and some pretty trashy wheels.
We'll cover the the real weight reduction attempts in the next post.
... did you know, that before I started this thread, I've only started 22 threads since 2010? *shakes head*
#2
I was very disapointed with the quality of the plastic in the stock kit. When i'd lift a corner, the chassis would twist rather than the suspension move. I... now understood why it came with crazy stiff shocks. The actual suspension was the chassis.
Tamiya, and 3 Racing both sold carbon chassis kits for this car. I suspect they won't actually be lighter, and... there is this thing called a budget. And I planned on keeping this thing pretty cheap. Tamiya also sold all of the kit plastic in carbon injected form.
Tamiya claimed the parts were lighter than stock. On average, I think I saved a gram. But the parts varied from 1-2g heavier than stock to 5g lighter than stock. With no real rhyme or reason. Total weight savings, not including that aluminum shaft, was 9 grams.
Tamiya, and 3 Racing both sold carbon chassis kits for this car. I suspect they won't actually be lighter, and... there is this thing called a budget. And I planned on keeping this thing pretty cheap. Tamiya also sold all of the kit plastic in carbon injected form.
Tamiya claimed the parts were lighter than stock. On average, I think I saved a gram. But the parts varied from 1-2g heavier than stock to 5g lighter than stock. With no real rhyme or reason. Total weight savings, not including that aluminum shaft, was 9 grams.
#3
I did pick up a brushless system for it. Based on price, rather than weight. I got the SkyRC Toro package, and threw that in the car. I also swapped out the shocks for some 3 Racing parts. Controlling the car had been trouble.

Take note of that steering servo. That servo is a DRFT-303. As it turns out, they have pretty lazy centering, and much of my frustration driving r/c cars was based on buying a $6 servo. ... don't buy that servo for anything fast.
Look at how far forward that CG is. That's with a super shorty 2650mah pack all the way back in the chassis.
In another attempt at lowering the weight, I attempted something very silly. That was to glue the rear cluster together, and remove the screws. It didn't work. The Nylon they inject with the carbon just won't bond to anything.
Now we run into a lack of pictures. I have a few things to do to the car, in the short term. I have the rest of the aluminum screw kit to install. I have aluminum suspension bellcrank pivots. And that aluminum top shaft you saw earlier. those things should lower the CG.
A few other notes. If you're taping in a battery, be sure to put down double sticky tape in the bottom of the chassis, as well as a strap over the battery. Use a good steering servo. And a high torque servo saver. If a car is traction rolling, FIX THAT PROBLEM before you break parts.
And then comes tuning. I've been all over the place on gearing. And with diff settings. Right now, the diff is darned near locked.
I'll take it out this week, and see how it's doing.

Take note of that steering servo. That servo is a DRFT-303. As it turns out, they have pretty lazy centering, and much of my frustration driving r/c cars was based on buying a $6 servo. ... don't buy that servo for anything fast.
Look at how far forward that CG is. That's with a super shorty 2650mah pack all the way back in the chassis.
In another attempt at lowering the weight, I attempted something very silly. That was to glue the rear cluster together, and remove the screws. It didn't work. The Nylon they inject with the carbon just won't bond to anything.
Now we run into a lack of pictures. I have a few things to do to the car, in the short term. I have the rest of the aluminum screw kit to install. I have aluminum suspension bellcrank pivots. And that aluminum top shaft you saw earlier. those things should lower the CG.
A few other notes. If you're taping in a battery, be sure to put down double sticky tape in the bottom of the chassis, as well as a strap over the battery. Use a good steering servo. And a high torque servo saver. If a car is traction rolling, FIX THAT PROBLEM before you break parts.
And then comes tuning. I've been all over the place on gearing. And with diff settings. Right now, the diff is darned near locked.
I'll take it out this week, and see how it's doing.
#5
#7
A buddy of mine is a fanatic of the ford fastiva from the 80s... He has like 5 some stock some motor swapped and one purpose buikt track car ... He isnt the only one he is within a group of guys that worship these cars ... And have found stupid/cheap ways to get them to go fast ...
One of the most important mods for these cars is remove as much weight as possible from behind the front axle... Meaning you want the cg as far farward as possible like if you could put the cg right behind the front axle that would be the hot set up ... So with that being said rear traction is not a issue the less weight on the back tires just allows it to track . no drifting or pushing ... So 0 camber /0 toe/ mild springs with thick oil . and ultra low ride height ... And super low rc.
For the front more than normal toe out / traditional camber / stupid firm springs and heavy oil . lowest cg as possible as well ... Glue the tires if needed ... Ive driven his car and it just does what you tell it period ... No power steering , no tq steering issues (with pos unit ) stops well ,which is part of the firm front setup ... You dont want any extra weight transfer to front under braking ....
Hope some of this full scale info helps . cool project .
Btw make the front a spool glue it up /drill it out . make it light ...
One of the most important mods for these cars is remove as much weight as possible from behind the front axle... Meaning you want the cg as far farward as possible like if you could put the cg right behind the front axle that would be the hot set up ... So with that being said rear traction is not a issue the less weight on the back tires just allows it to track . no drifting or pushing ... So 0 camber /0 toe/ mild springs with thick oil . and ultra low ride height ... And super low rc.
For the front more than normal toe out / traditional camber / stupid firm springs and heavy oil . lowest cg as possible as well ... Glue the tires if needed ... Ive driven his car and it just does what you tell it period ... No power steering , no tq steering issues (with pos unit ) stops well ,which is part of the firm front setup ... You dont want any extra weight transfer to front under braking ....
Hope some of this full scale info helps . cool project .
Btw make the front a spool glue it up /drill it out . make it light ...
#8
A buddy of mine is a fanatic of the ford fastiva from the 80s... He has like 5 some stock some motor swapped and one purpose buikt track car ... He isnt the only one he is within a group of guys that worship these cars ... And have found stupid/cheap ways to get them to go fast ...
One of the most important mods for these cars is remove as much weight as possible from behind the front axle... Meaning you want the cg as far farward as possible like if you could put the cg right behind the front axle that would be the hot set up ... So with that being said rear traction is not a issue the less weight on the back tires just allows it to track . no drifting or pushing ... So 0 camber /0 toe/ mild springs with thick oil . and ultra low ride height ... And super low rc.
For the front more than normal toe out / traditional camber / stupid firm springs and heavy oil . lowest cg as possible as well ... Glue the tires if needed ... Ive driven his car and it just does what you tell it period ... No power steering , no tq steering issues (with pos unit ) stops well ,which is part of the firm front setup ... You dont want any extra weight transfer to front under braking ....
Hope some of this full scale info helps . cool project .
Btw make the front a spool glue it up /drill it out . make it light ...
One of the most important mods for these cars is remove as much weight as possible from behind the front axle... Meaning you want the cg as far farward as possible like if you could put the cg right behind the front axle that would be the hot set up ... So with that being said rear traction is not a issue the less weight on the back tires just allows it to track . no drifting or pushing ... So 0 camber /0 toe/ mild springs with thick oil . and ultra low ride height ... And super low rc.
For the front more than normal toe out / traditional camber / stupid firm springs and heavy oil . lowest cg as possible as well ... Glue the tires if needed ... Ive driven his car and it just does what you tell it period ... No power steering , no tq steering issues (with pos unit ) stops well ,which is part of the firm front setup ... You dont want any extra weight transfer to front under braking ....
Hope some of this full scale info helps . cool project .
Btw make the front a spool glue it up /drill it out . make it light ...
#9
I have this chassis and before I move to another fwd platform I was trying to lighten it up as much as I could and was inspired by my 1/18 Scalpel to design the rear end like the front of it. Never got past the idea stage and just quick drawings but it may give you some idea.
#10
Well, I brought out the FF03 today. I haven't installed all the lightweight parts yet. But... in comparison to my TA07, and Sakura XI... Well I was within "I'm a terrible driver" distance of both (around .3 second). Moving the battery to the front of the battery tray did the trick. As well as putting the bumper on the car. Between the two, there's a whole lot more weight on the front end. The motor doesn't get hot yet.. so between a fan and a taller pinion I could eek some more speed out of it too.
#11
Well that was shocking. I swapped out the steel top shaft and gear for the aluminum. That saved 11 grams. I saved another 20 or so grams swapping out a bunch of other screws for aluminum.
I also saved another 2 grams swapping out the metal suspension pivot pins. All high up in the car! Yay.
Next step, is to dive full on into seeing if can-am gearing will be ok.
So.. where will I continue this crazy weight savings adventure? The ESC can be swapped for something lighter. And I can remove the fan.. and some of the heatsink. I can take the reciever out of it's case. Sadly, I want to put the foam bumper back on, which is going to slap a lot of that weight right back on the car.
I also saved another 2 grams swapping out the metal suspension pivot pins. All high up in the car! Yay.
Next step, is to dive full on into seeing if can-am gearing will be ok.
So.. where will I continue this crazy weight savings adventure? The ESC can be swapped for something lighter. And I can remove the fan.. and some of the heatsink. I can take the reciever out of it's case. Sadly, I want to put the foam bumper back on, which is going to slap a lot of that weight right back on the car.
#14
I’m planning to go Sunday,( no Bears game) most likely just to watch. Now that on road has moved back to Sunday. I don’t think I can get there in time to run.
#15
Well, I did the math. 16.2 grams total. But most of those losses were above the beltline, so will help keep that CG low.
Here's the most satisfying part.

Check out that difference in weight.
Here's the most satisfying part.

Check out that difference in weight.



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