Tuesday, 31 July 2007

Video of run and crash

http://www.youtube.com/watch?v=tJPcL6KvPBo&mode=related&search=

Here is the video of the run. You can see the car under control until I jump off the wall then all hell breaks loose!

Sunday, 29 July 2007

Worlds Fastest Rc Car Challenge, Callifornia Speedway

It was all worth it!!

All the racers met at a local diner and had breakfast before heading to the track. The track was one lane of the california Speedway Drag Strip and had concrete wall all the way around. The track was slick and had zero grip! It was like running foams on wet tarmac.

I started my car and tried to tune it for the 30% Odonnel fuel and the 95 deg F temps. I had to lean the engines nearly 1 1/2 turns to get them to keep running.

I did a quick pass without the shell and a very short run up to the speed trap just to see if the engines would not flame out but all but one stopped before crossing the line at 48.2 mph.

It was hard to get track time as the electric cars were ready to go at a few seconds notice where i had to start all the engines and tune them up before running then back to the starter box after one had died.

Next run I tried to launch the car and keep the engines running. I did the same short run up and no shell. This time one engine stopped before the launch and the car did 68.7 mph croosing the line with no engines running.

I leaned the engines a full 3/4 turns and tried again. I extended the run up to around 200m and launched very steady. I managed full throttle at about 100m to go to the trap and got 88 mph. All 3 engines were still running so I managed to get the car back for another run. Right this is it!! A quick refuel and its a full run up at full throttle.

I jumped off the wall to fill the car and my knee caught the battery lead to the transmitter. The car took off and smashed into the wall loosing the front end. The car then took off up the drag strip crashing into the timekeepers chair and that was it.

Lessons learned.

The track conditions wer not good and I needed to have the option of running a smaller gear. I tried to go to fast and needed to get post a decent speed around 100 - 120 before gearing up.

The engines need to be changed for something with a lot more bottom end punch. Next plan is to:

Change the rear pulleys from 16/18 to 15/19.
Change the side pulleys from 19/14 to 18/15 to maintain 3% overdrive
Change the gearing to 15/49 45/19
Make and install 3 x alluminium clutch shoes
Install Novarossi 3 x 35 plus 21 engines. or maybe change out the R03 and the Sirio to RB Xenon Rs
Install a steering gyro

I also need a new shell as the blue one is toast!

I have pics and vids i'll post later

Cheers

Wednesday, 25 July 2007

Packed and ready to go

The car is back together and tested. Just in time for the big event!

The bags are packed and everything is ready. I'm off to Los Angeles to attend the Worlds fastest RC Car comp at the California Speedway, Fontana on Saturday 28th July!

I think I have everything. I'll take some pics and video of the event and post them here

Monday, 23 July 2007

A bit of an "off"

Just back from testing at Mallory Park. The track was a bit wet so we waited around until it was drier. I ran the car up the straight and there was very good signal all the way to the bottom of the back straight.

I ran the car towards me and gunned the throttle. The car was heading in my direction so I made a slight correction and accidently let go of the button that reduces the steering to 15% and it took off to the left and into the grass. At that point it was doing 88mph.

Broken front wishbones, front bumper, lost drive shaft and lost one way drive cup!!

Not bad really seeing as it flew about 8 ft in the air for about 30 ft.

The new parts will be here tomorrow so its a last rebuild before the event.

Cheers

Saturday, 21 July 2007

Pics

I just realised I havent got a decent pic of the finished car on the site. Here it is




















Friday, 20 July 2007

Rain Rain Go Away, Come Back After Testing

I think I will give up building the RC car and build an ark instead. 5 days non stop rain! I have 5 days left before its off to the comp and I still havent found out how fast she will go. It looks like we will have a test on Monday as long as its dry... yeah right...

I made an aluminium Centax clutch shoe and tried it on the Xenon R and it looked real promising. I tried to make another one today but the lathe broke.

Roll on summer

Wednesday, 18 July 2007

Slight setback

I went to Donnington race track today for the final testing before the comp and it didnt go quite as planned. We started the engines and then lost radio signal so stopped them again. there was a hissing from the car and saw the RX pack was shorting itself out and getting red hot under the fuel tank.

We quickly removed the top deck and threw the pack on the ground where it caught fire!! 5 secongs later and it was goodbye car!!

The spare RX pack was no good either so we packed up and went home.

Better luck tomorrow

Saturday, 14 July 2007

Modified Radio

I think I might have solved the radio problems. Here is a pic of a 9db aerial attached to the Spektrum system. It has a much higher range but needs to be kept vertical.




I also found that the antenna on the receiver needs to be vertical and not kinked to achieve max range. If your thinking of doing the mod you could fit a 5db antenna that is less range but more forgiving of the vertical angle. Here is a pic of it

You can see its a lot smaller so easier to handle. I tested the range of the 9db antenna and found at 0.6 miles it was working perfectly. I then ran out of range.
Next is to test it in the car

Wednesday, 11 July 2007

Long Marston Testing

Today didnt really go as planned. we got to the drag strip and started the car and found the radio had no range whatsoever. I changed out the receiver and tried again but no luck so we moved to the end of the srtip where the range was better but not good.

I managed 4 runs and maxed at 81 mph which is no better than the last runs. I stood as far away as I could while still in control of the car and floored it. The car whizzed past and the failsafe just cut in. You can see in the vid the car veering to the side and the revs dropping.

http://www.youtube.com/watch?v=VcZGFReC0ek

I also had problems with the engines as the back 2 kept cutting and due to the radio problems couldnt keep the car in control to be able to turn around and run it back for a retune. It took 4 hrs to do 4 runs!

The drive train problem was a lost drive pin. I need to locktight them in

At the end of the day I changed the RX pack to a 6 cell and voala!! Problems solved but by now it was time to leave.

Off to mallory park for some more running on Friday. I'll be on my own so no vid but i'll attempt to tune the engines

I have the V6 clutches on order and the 9db anenna turned up but no cross over from the TX unit yet.

Tuesday, 10 July 2007

Home early

Im back home a bit early so had a chance to work on the car. I have installed the 4WD system. See below





The side belt fitted perfectly and the belt tensioner moves the belt down just enough so the belt does not foul the 1st engine exhaust manifold.

The drive train is as follows

Front tyres 70mm.
Front axle one way with 24T pulley
Front layshaft pulley 17T
Front side pulley 14T
Middle side pulley 19T
Middle pulleys 18T
Rear layshaft pulley 16T
Rear axle pulley 18T
Rear tyres 75mm

2nd speed pinion 22t
2nd speed spur 44t

This give a 2nd gear final drive ratio of 2.25
A top speed at 41,000 rpm of 157 mph
and a front to rear overdrive ratio of 1.0094

I'll be testing the car tomorrow at Long Marston Drag Strip

Thursday, 5 July 2007

Back at work

I am back at work for the next 4 weeks so cant work on the car. I have ordered the equipment to convert it to 4 wheel drive and have already reduced the gearing to help with clutch slip.

After the 79 mph run the clutch shoes were shot and the 2nd engine 2nd speed clutch had come loose. I have also found the reason for the tightness in the drive train and looosened it all up.

I am working on a solution to increase the radio range by fitting a 9db antenna to the spektrum system. I have also fitted a 6 cell pack to the receiver. Everything is ready for a decent run some time in August