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Re: Aussie EV Autocross Special

Posted: May 25 2017 9:24pm
by galderdi
Agreed, gear changes are an issue. As usual though I am constrained by parts that I can scrounge.

As for the clunking, I have checked the videos (this time with the volumn up) and it is definately the suspension moaning. This is because most of the suspension components aren't running bushings. It groans and moans on anything but the smoothest surface. The driveline only has the standard whir of the motor fan.

Re: Aussie EV Autocross Special

Posted: May 26 2017 2:02am
by Hillhater
kiwiev wrote:Just another thought for your next car is gear changes the reason Tesla is the fastest acceleration car is no gear changes and good constant torque. ..
Yes 1000+ Nm of Steady torque at the motor, a 9.7:1 reduction transmission, ( so near to 10,000Nm at the wheels!)....and a motor that will run up to 18,000 rpm. will all add up to decent accelleration ! :wink:

Re: Aussie EV Autocross Special

Posted: Jun 06 2017 1:34am
by galderdi
My next event is a motorkhana and is coming up soon. It will be held at Willowbank on June 18. IF anyone is local feel free to come and take a look. Spectators are free. I'll post another update after the event.

Re: Aussie EV Autocross Special

Posted: Aug 06 2017 9:45pm
by galderdi
I had another competition day yesterday. I was competing in round 4 of the Queensland Motorkhana Championship.
Runs 3,5 & 7 are terrible, My fault not the car. But those 3 out of 12 runs were enough to ruin my chances for the day. I finished mid field.

Re: Aussie EV Autocross Special

Posted: Aug 14 2017 9:32pm
by galderdi
My next event is a Khanacross on Aug 27. This one is being hosted by the Lotus club so there should be some interesting scalps to claim. It is to be run on the small circuit at the back of Lakeside and should suit my car. I am really looking forward to it.

Re: Aussie EV Autocross Special

Posted: Aug 27 2017 10:28pm
by galderdi
I had a ball at the Lotus Khanacross at lakeside. The track is quite tricky with a couple of blind corners. It really would help to have track time on this one. My first few runs were average at best but I did improve on my last few runs. I really struggled due to rear end grip. You know it’s bad when you are over steering in a front wheel drive car. I managed to come 34th from 66 competitors. That’s not bad considering the quality of the field. I beat 6 out of 13 Lotuses and 9 out of 16 Porsches. If I wasn’t retiring the car I could put better tyres on the rear and improve the rear geometry and I would be confident of picking up quite a few places. Overall I am quite happy.

I had a problem with my camera and only got 1 video with telemetry. It’s not the fastest run and watch for the plover at about 1:22

Re: Aussie EV Autocross Special

Posted: Sep 11 2017 10:09pm
by galderdi
I had a great event on Sunday.

For a while the results were up in the air.....quite literally. We had a mini tornado which flattened our timing tents and associated equipment. The timing tents were thrown about despite being weighed down with concrete blocks. Our volunteers conducting the timing were shaken but unhurt. When I first looked over to understand the cause of the commotion I first thought a wayward car had somehow bowled over the time keepers. I am so glad that was not the case. A handful of timing result sheets were sucked up into the vortex and continued to rise almost straight up until they eventually reached sufficient height to become too distant to view.

But now the results are up in the cloud. So I can confirm I managed 6th place outright. That isn’t too bad, as usual one particular test cost me quite dearly but overall I think that only cost me one place realistically. Looking at the times I am confident all the improvements going into the new car will have me competitive against the guys at the top. I don’t expect to be consistently quicker than them as they will still have a significant size advantage. But I will be closing that gap to some degree and I will have other advantages that will somewhat compensate for the rest of the gap.

Here are a handful of videos from the day:

Re: Aussie EV Autocross Special

Posted: Jan 09 2018 5:50pm
by galderdi
Here are the pics of my latest project. It is similar to my last one but incorporating a lot of learnings from last time.

I expect it to be about 20% lighter. Plus it is rear wheel drive, narrower, better suspension design, better aero etc etc.

I still have a fair amount of work to complete it and the deadline is looming on Feb 11. I'll provide another update soon.
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Re: Aussie EV Autocross Special

Posted: Jan 09 2018 11:39pm
by jonescg
Looks sick! What components are you looking to use?

Re: Aussie EV Autocross Special

Posted: Jan 09 2018 11:59pm
by galderdi
Thanks. I am fairly happy so far.

I will be transferring the components from my previous car.

The gearbox is from a nissan N13 Pulsar.
The motor is an advanced DC 8inch.
Controller is a ZEVA 1000 amp.
Batteries are a 144V nominal portion from a Chev Volt.

These components worked exceptionally well in the old car. But I was losing the torque advantage through wheel spin because it was FWD. Plus this car is likely to be around 20% lighter than the old one. Being narrower will make it quicker through slaloms and the like and I expect the improved aero will improve response from about 70kmph (40mph) - 100kmph (60mph).
The improved suspension geometry should result in an ability to hold more speed through the corners.
The improved steering rate should result in better ability through tight corners plus less distraction for the driver (me) frantically turning the wheel from lock to lock.

I have also added passive rear steer. This will be turned to subtly turn the rear end around tight corners. I will tune it to neutral for faster courses.

All in all it should be a very satisfying car to drive. I am getting really excited to give it a whirl.

Re: Aussie EV Autocross Special

Posted: Jan 28 2018 10:21pm
by galderdi
Here are a couple of the latest pics of my new car. I have encountered soem delays on the steering components. We'll see how it goes over the next couple of weeks.

Re: Aussie EV Autocross Special

Posted: Feb 27 2018 1:49am
by galderdi
I got the car running last night. This is a huge releif as it means I am fairly certain of competing in the event this Sunday. I do still have a few things to do but they are fairly minor.

I also weighed the car (As best I can). The car came in at 480Kg with weight distribution of about 44/56 toward the back which isn't too bad.

The first drive felt very good. I think it has promise. I just need to do a wheel alignment, brake bleed and some minor additions to be ready for Sunday. I should have some good videos early next week.

Re: Aussie EV Autocross Special

Posted: Jan 10 2019 10:32pm
by galderdi
Hi everyone. Appologies for not posting for a while. It has been a heck of a journey (not implying it is over).

The car is coming along nicely. But it still isn't competitive. I seem to be hovering around the mid field in most results. Not bad in itself as I am usually up against some seasoned competitors in some goo cars. So as I usually say I am happy but not content.

The second last event of 2018 was the Noosa Hill Climb. It was only my second time at the event and I improved by 4 seconds. The car was still understeering but was managable. But the understeer prevents me from gaining too much confidence and holding corner speed. So I am still focused on improving that aspect of the car. Here is a video from that event:

The last event of 2018 was an autocross/khanacross. But it was very very wet which emphasised the understeer to the point where is was not managable. I don't have a video for that event.

I started with a check of all the suspension geometry including Castor, camber, king pin inclination, roll centres, toe in and Ackerman angle.

Castor was about right on the driver side but significantly more aggressive on the passenger side. This will be resolved as I complete the new front contro...l arms.

Camber, king pin inclination and roll centres were about where they need to be.

Toe in was correct but will need to be adjusted again as it will be impacted by all the other changes.

Ackerman angle was a little out on the passenger side but not enough to warrant a change in the short term. The driver side was out by a bit more and I have now replaced the adaptor plate to bring it in line with the passenger side.

I have made some solid progress on a second nose for the car. The first nose is for lower speed events where it is an advantage for the tyres to be in front of the nose. The new nose is sleeker, and will include a wing for additional downforce (maybe). The two noses are interchangeable depending on the upcoming types of events. The nose and wing are structurally complete and just need the panels to be added.

I have created some ballast in the form of a 10kg lump of lead. This can be added or removed depending on conditions. I intend to only include it in wet weather where the understeer characteristics seemed to be pronounced.

I have made new front control arms. These are designed to address the inequality in caster from left to right. They are also designed with a slight bend in the front bar of each arm. The bend is to improve the angle of the rose joint attaching to the chassis mount. I was concerned about the bend creating a weak point in the control arm. So you can see I added some significant reinforcing to ensure it can handle the forces.

I am also part way through a modification of the hydraulic handbrake setup. The existing setup has a single master cylinder serving both rear wheels equally. The braking capacity was insufficient to overcome the grip of the rear tyres. The new setup will have dual master cylinders opposing each other with a handle in between the cylinders. Pushing the handle forward will operate the right rear brake and pulling it back will operate the left rear brake. Operating one of the rear brakes at the same time as some mild acceleration should enable the car to perform very tight turns when required (one of the requirements it has struggled to satisfy in the past). The car will retain the cable handbrake for parking and as an emergency brake. I have created the adaptor brackets required for the modification but I will need a full weekend to install system, rerun all the hydraulics and bleed the system.

Re: Aussie EV Autocross Special

Posted: Jan 11 2019 7:43am
by jonescg
The weight distribution being a little rear-biased would probably explain part of the understeer, and the lead weight should give some indication if that's the source of the problem. But as for four-wheel dynamics, I'm not the guy :)
Awesome that you've got a reliable rig though. Shame we didn't see it at the expo, but racing it that weekend is a fair excuse!

Re: Aussie EV Autocross Special

Posted: Jan 13 2019 6:22pm
by galderdi
I have made some adjustments to the car. I still have some more to do. Here is the latest photo.