Lightyear's SE Replica Track/Road MX-5

[lightyear]

It felt quick down the hill. I braked at 50m, turned it in, then held it flat until I brake at the bottom. Trust in thy wing. Can't wait to see how it goes at the Island. If I can get close-ish to 200 at T1 I will be wrapped. I think my P.B is 186.

[MrsB]

yep we were suffering understeer when we were there at state was over 20kms down was costing some serious time - my best over the top is 165 on slicks - agree 200 thru 1 is pretty cool - you need to go drive full track at eastern creek too - turn 1 is fun there as well

[lightyear]

The wing on your car is probably the crappest part. A real wing and nice airdam/splitter will make a huge improvement on your car with the power you have.

If you watch my video, the car was under steering down the hill too. It actually puts the left tyre off the track slightly on the right kink.

[MrsB]

Have a new wing and splitter underway - should have for the next state round so will be interesting to see how it goes

[lightyear]

Can only help.

I decided to make my splitter larger too. I had some left over lightweight plywood, so cut it up and bolted it on. The splitter was larger originally, but I cut it down to suit Clubsprint rules. It had so much understeer at Winton, it was hard to keep speed up. Coming out of the S's it was a matter of holding the foot flat, and waiting to see if the car would stay on the track on exit, or hit the wall. It's a lot easier to control understeer than oversteer, but still, both are slow.

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[rascal]

It's a lot easier to control understeer than oversteer, but still, both are slow.

Agree, and if wondering understeer is slower than oversteer .
I had the misfortune to be on a mismatched set of tyres at Winton, and first sessions the dud tyres were on the rear, and it had massive oversteer and was slow. Adjusting bars/shocksDand cranking up the wing AoA made little difference . I swapped them to the front for the last session, and had massive understeer and was slower again.
So oversteer was quicker than understeer, on same car, same conditions, and also much more fun to drive. Understeer sucks..

[Apu]

Dave, can you show a couple of pics of the brackets you have used to secure the splitter please?

Are they quick release or PITA release?

[lightyear]

Understeer forces you to slow down, that's probably why it's slower.

There are no fancy brackets, just some square tube bolted to the car with more vertical alloy to pick up the forward area horizontal tubes. No screws any more, they don't work. I will only use bolts and washers from now on. It isn't too hard to remove, maybe 10 minutes, or less with a 10mm socket in the screw gun. It's the ducting that will make it difficult to remove. I don't plan on taking it off any time soon. Just need to try not to damage it.

[MrsB]

Looking good dave - be an interesting thing

[lightyear]

Cheers.
Here is my dodgy video edit from Winton short. At least I used HD this time. Basically a session with the mobile chicanes (MX5 club) on the track.

https://m.youtube.com/watch?feature=em- ... =mv-google

[lightyear]

Judging by the vibration today, I would say the new wheel bearings are gone too. I will see what the rep says, but in the mean time, it might pay to shop for better bearings. Oem Mazda ones lasted for a long time.

Phillip Island put on a magic bit of weather. It was cold, but no wind until lunch, and sunny till mid arvo. I was in group 2, and couldn't get a lap without traffic. Best was a 1:44.2, I shifted to group 1, and had a nice open track to drive on. I did a 1:33.9, played with the wing and did a 1:33.8 before the bolt heads completely ground away, and the splitter was dragging on the ground (road springs at 8 and 6 kg's front /rear will do that) . Racechrono was showing low to mid 1:33's until the last session with the wing at max AOA. 1:32.7 optimal.
The car is truly exciting to drive, I can't remember being so pumped about driving a car as I was today. I jump out of the car and feel like I have been injected with drugs, must be the adrenalin. I love it... Your brain doesn't think it's possible to get around T1 at the speeds it's going, you have to really conquer what you think you know. And just drive it knowing it will stay on the track with your foot flat to the floor on exit after just a slight brake to get the front to turn in. I haven't gone over all the data, but 196km/h minimum is the best I saw in one session.
Pretty f@&k'n happy with the car I must say.
I think with another hour of driving I will be able to perfect my trail braking into corners like T4. I really learnt (taught myself) a lot towards the end of the day. It's not all about brave pills. Corners like T2 I learnt to trail brake well a long time ago.

It can't be too far away from being one of the quicker MX5's to lap Phillip Island.

[lightyear]

Need to edit that post. I put 30's instead of 40's.

[beavis]

All in all, you're getting to the limit now without spending lots of dollars.

Lets say you want to fix a few known issues, cost would be roughly:
Extended Lower ball joints - $300? (So you can properly setup the front)
Shocks & springs - $2000? (because the street coilovers are in over their head now)
Boost control - $0 to $??? (at a minimum you could be running electronic boost ctrl, but would be nice to have a way to control the boost creep you have.)
Also you are overdue for coolant reroute.

Would that gain you much time? I'm not sure it would... maybe you can get a bit more out of the tyres with a proper setup.

[MrsB]

awesome effort on the time. but save your money on the coolant reroute - waste of effort - just buy a decent crossflow radiator and put and oil cooler on it and save yourself the headaches

[NitroDann]

Shocks & springs - $2000? (because the street coilovers are in over their head now)

North circuit record is held by a car with its original na6 shocks and chopped springs.. Just saying.