gcooper

Multiply the diameter *PI
2.0 tire * 3.14 = 6.28 Circumference

Divide the pinion into the spur
15 pinion / 128 spur = 8.53 Ratio

Multiply Ratio * the Final Drive of any car (namely the 04)
8.53 ratio * 2.13 TA04 tranny = 18.17 Final Drive Ratio

Divide the final drive ratio into the circumference
18.17final drive / 6.28 Circ = .35 Rollout

This is about as simple I can make it to show you how to get the rollout. You can follow it with a calculator to see how the numbers get divided & multiplied. This is not metric but the principle is pretty much the same.

Some people usually use a spreadsheet like Excel or Lotus and plug and play. If you don't have those make a graph on a piece of paper.

Many times people focus on the Final Drive ratio rather than rollout. I know for me that usually is the case.

A big advantage, if you can afford it is getting the Orion LCS. It will help you see what kind of times your car is turning by the gear changes you make. If you cannot get that then ask a buddy to stop watch ya on the track.

You will find out that going blistering fast down the straights does not mean you are fast. Usually you will suffer on the 10 or so turns on the infield.

Hope this helps.

Coop

hawker

Thanks, I'm going start in the middle of the gearing range and play around from there, I know that rollout on cars is completely different, but if people are urnning say 45, it seems strangeto be running a rollout of like 36, oh well, alls fun and games, it good racing, so I'll keep at it, thanks.

gcooper

Let us know what you get to work along with the track size.

Coop

TF

Hello All:

I ran my 04 for the first time last night, I had difficulty running it due to a huge understeer.

I think I fixed the basic set up to correct this, but it seems the car has a mind of its own...

Anyone want to suggest your set up to get maybe a slight oversteer on this machine?

Cheers to all!

psycho

TF

Can you post your setup? I don't think there is a lot we can help you with unless we know that. The first thing that I would do is run softer tires or softer inserts, if you feel that you're running the right tire. Tires are the coursest adjustment you can make to the car, so you should always start there.

IMPACTPLAYR

iTrader: (7)

TTT

IMPACTPLAYR

iTrader: (7)

Does anyone have the SSG parts for their 04?? I just reaquired my old car and have already spent a little money putting new parts on it..... I am concidering the SSG topdeck, and shock towers...otherwise I will go with the standard carbon towers.....

BTW: my car has finally be returned to 04R status.... had to scrap that horrible pro chassis!!!!

sty

iTrader: (7)

Hi Guys,

Just got my TA 04 TRF today, cant wait to fix it up. I actually own a S and have bought quite alot of hopups on it. The hopups include the ssg top deck and damper stay. The ssg damper stay really is lower and better I guess it should be a worthwhile investment. By the way, I guess anyone who wants to hop a TA04 S should not consider as it will be very expensive and it will be more cheaper to get a TRF or R tune Kit.

hawker

Hey guys, majors problems here, in 5 days time, the State Championships are on, down here in Australia, Brisbane.

I'm running the TA04 TRF with a Johnson 540 Grey Can motor, and from my previous posts I am have trouble getting speed, I've bought so many different 48pitch gears its not funny trying to figure out a good ratio.

I've strated to find some speed but it keeps on overheating the motor, I'm running 87spur and 36 pinion, the lowest pinion I can go is 33 with that spur, I tried that, I lost all this speed but the motor was still over heating.

I got 84, 81, and even 75 spurs and a couple of pinions, my budget is VERY tight and I have trouble buying new gears, so can anyone give me a ratio that will give me speed, or one that has worked for you other guys?

PLZ help as I've only got 5 days till the states, and I don't wanna waste my entry!!!

madjack

iTrader: (28)

84/35 works for me!

hawker

and you don't over heat your motor?

looks like i'm close, I'm going to buy a 90t spur and try that as well, but i'll get a 35 too, the track we have is very open, too long straights with a tightish infield

Rod M

iTrader: (4)

I run 85/35 here as well, with the johnson 540,

the motor gets hot after 5 min but you should be fine

chef88

iTrader: (75)

Hawker, Maybe your motor needs to be broke in. those brushes are hard. When I buy a new motor. I dip it in water to give it a head start. or you could try a different motor, it's pot luck but some are better than others. hope that helps MJ

psycho

hawker

There's some good suggestions so far. Definitely make sure your motor is broken in. Depending on how hard the water is in your area, this may take a long time. Look through oval holes on the can and you will see the comm and brushes. You want the brushes to be seated nicely. I usually dip motors until there are two stripes on the comm about 2mm wide where the brush faces haven't started touching the comm yet. If you can get more motors, pick up 3 or 4 and break all of them in. I usually buy motors 3 at a time and I end up with 1 good one and 2 so-so ones when I look at them on the dyno.

As far as gearing goes, these motors have a very narrow range where the perform well on the straight and in the infield. Unless the track you race on is really large, I think you're probably a little overgeared. Just because everyone else is running a particular gear ratio doesn't mean it is right for your motor. Another thing you might also look at is increasing the size of the gears. Mike Reedy has a theory about this and it seems to be evident on the track as well. The theory goes that even with identical gear ratio, a larger pinion gear will give the car better acceleration than a smaller one. I don't know for sure why this is, but my guess is that the angle of the teeth is such that it creates less drag. Something to think about.

Also, check the drivetrain. You want to eliminate as much drag as possible. Make sure the front belt is fairly loose. If it's tight, stretch it out a bit to loosen it up. Make sure you don;t have ay bearings that are binding.

Finally, be nice and smooth on your turns. If you crank the steering, you scrub a lot of speed. make nice arcing turns and you'll see a big difference in your laptimes.

I hope that helps and good luck!

Jekyll

iTrader: (8)

Depending on the track layout I run a FDR of 4.92 to 5.43. And yes the motor gets very hot. However, the motor doesn't seem to be effected by the heat, yet. I have been running the same motor for about 5-6 months.