Red Devil mkII - The Journey Continues

[seangti]

I ran at lakeside Timeattack last weekend with the car all sorted and optimized from some earlier fiddling with sway bars.

I ran a best of 63.6, with my best 3 laps within 0.1s of each other. This is 0.5s slower than I'd ran on the previous turbo and previous old tyres. By way of power/peak speed, my silver car would peak at ~178kph, this set-up was 185-188kph and with the previous turbo and tune was ~192-194kph. There is more time in the car, about a second according to my data, so I may eventually get that 62s lap. Based on the analysis and times achieved, I'd say the car is 0.5s slower in the current state of tune.

The V70 tyres were really good at speed and good under brakes, a little lesser around mid corner on the tighter stuff, they seemed to roll over a bit more than the Bridgestones RE55s did. I ran them to a hot temperature of 34psi. Corner speed was much the same as the old tyres, though I was incrementally quicker in some sectors than when I did the 63.1s lap... The time loss is mostly down to lesser power to get out of the corners and down the straight.

With the car running well, I decided to run a session without the wing. Yikes, the difference was obvious. I'd say it's much to do with the relatively aggressive rear sway bar set-up I'm running so it's all complimentary at the moment so I've essentially unbalanced it by removing the wing. By just removing the wing, the rear was very twitchy at speed, the car really wanted to pivot and my corner entry speeds were down by 5-10pkh. It was a crazy unnerving to the point that I came in from the session early. Really good validation.

Off to Morgan Park at Warwick this weekend for a driver training day.

[Martin]

Sounds like you're having a lot of fun!

I took the newly refreshed red devil back to Lakeside over the week. Since it's last outing I've done the FTG turbo, retune, new front rotors (DBA T3) and new pads (QFM A1RM) and softened the rear sway bar from hard to soft.

The change of the rear sway bar was probably the biggest change to the detriment of lap time.

I'd be keen to get opinions on running the front sway bar hard and rear sway bar hard, I think that's my next thing to try. With the rear hard and front soft, it gripped nicely but lacked feel. It was toey/over steery on cold tyres, but ok once hot.

I'm racing a Nissan Pulsar in the Pulsar challenge and have had to learn fast on this topic.

Don't go hard on the front (stay soft as possible) - hard will induce more understeer
A little toe out can help turn in at the track, 0.5 mm toe out (each side for a total of 1 mm) measured at the rims
(Pain in a$$ doing this to a daily drive for a track day)

Do go harder on the rear bar (for the track - revert to soft for the street)
If you get to the point where you are lifting the inside rear tyre off the ground:

• This reduces load on the outside front - aiding turning
• Adds some load on the inside front - helps traction during early pulling out of the corner

Have a think about the sidewall stiffness of the front tyres
The softer the sidewall is the more negative camber you need
With the Pulsar (dedicated track car) I'm running -3.5 degrees camber at the front and -3 degrees camber at the rear
(Obviously you probably can't get anywhere near that - it's just an example showing that negative camber helps heaps)
On my Skoda Octavia I have the SuperPro LCA's setup with -1.5 deg camber, it has awesome cornering ability!!
Over 53k of daily usage I've worn out my wonderful Goodyear F1A2 tyres but no unusual wear from the negative camber

34 psi hot pressure sounds low (FWD needs ~higher pressure) but I don't have any experience or information on your tyres
We are running the Hankook RS3 (classified as a semi slick) and they like 38~40 psi hot

[Machine]

Love your work, Shorne.

[Machine]

Hankook RS3 is a street tyre and should be run at higher pressure. Sean's running a true semi R compound and 34 hot is properly at the upper limit, if not a tad over.

[seangti]

Sounds like you're having a lot of fun!

I'm racing a Nissan Pulsar in the Pulsar challenge and have had to learn fast on this topic.

Thanks for input Martin, always great to hear from another tracker.

Yeah my current sway bar set-up is back to front on soft and rear hard. It felt really good with the new tyres, with the previous and very old tyres it was good once they were hot, but snap over steery when cold. I had Ken at Accurate Suspension do the corner weighting and geometry, he's renowned up here for setting up a lot of the track cars. I run something like -2.7 camber on the left and -2.2 on the right on the front (I think that's it anyway), can't recall the toe settings and have shims on the rear. I didn't want to run more camber as I drive the car on the street/to work occasionally.

Re the tyre pressure, as Ben said, being an R compound they start much lower. The fellow at Kumho motorsports suggested running them at 33-34 psi hot as the car is quite light. For a heavier car, he'd run them less.

[nat225]

Hankook RS3 is a street tyre and should be run at higher pressure. Sean's running a true semi R compound and 34 hot is properly at the upper limit, if not a tad over.

monkeen was running <33psi on the rs3

Sent from my GT-I9506 using Tapatalk

[Machine]

monkeen was running <33psi on the rs3

Sent from my GT-I9506 using Tapatalk

Yeah they're similar to AD08R, for which Yokohama recommend a similarly low hot pressure. There are two schools of thought on the ultra high performance low treadwear street tyres: either higher pressures in the 30's and low 40's or low pressures in the 30's. I've tried both and it's still hard to say if there's a big difference. I do know though that compared to proper semi-slicks, high performance street rubber absolutely sucks on the track and when they go off, they go off without any recovery! They just become greasy pieces of poo smearing all over the track. Yuck. A050's FOR LIFE!

[seangti]

Couple of pics from a boys weekend of driver training at Morgan Park with Safe Driver Training (SDT). We had a full day of lapping, over 150kms of circuit work, my arms feel like they're ready to fall off. Was awesome and learnt lots, big cheers to SDT and their trainers. Now a months wait for the season finale of Lakeside TimeAttack to put this in to practice.


Farm stay at a mates place.

[seangti]

Some video of the others

https://youtu.be/zxoboi2WW2M

[Machine]

Take out the "s" in https and it'll embed properly

[seangti]

Thanks mate, it was pasted and ran out the door without even looking. Cheers.

[seangti]

Had the final 2015 TimeAttack on the week, was great to get out again as it's been a few months since running at lakeside. Last time out was the first time I'd ran the kumho V70 tyres and I'd noticed significant tyre wear on the front left as below. I got specialist advice which indicated that the tyre wear was due to lack of camber (and over driving), so got the alignment sorted last week, now running -3.8 degrees camber front left to account for the right handed circuits.



The discolouration is from overheating of the tyre. A blend of lack of camber and over driving.




Anyway, for timeattack it was a hot day at around the 29-30 degrees though the car ran awesome and felt good with the increased camber. I got a new PB for the current set-up (new turbo and lower boost) of 63.34s. Had quite a few 63s laps which I'm quite happy with. This is still a slower time than I achieved with the previous turbo and higher boost of a 63.18. My goal is to crack into 62's, so that'll have to wait to next year. It's certainly in the car, but it's making me work for it.







I'm surprised at the stance from this shot as the car sits reasonably high from a lowered car

[seangti]

A brief video, not the fastest or best lap, but the fastest that I recorded with video and data.

[Eddy]

Hoyhoy.

That looks real good, Sean...

[Julzaac]

I noticed you had: Enkei RPF1 17x8, 35ET which are the exact wheels I want to go. Did you require any rolling or did they fit stock? I know Louis has the 16x7s and they are okay, just not sure about the extra width.

FYI running stock suspension / brakes (for the time being )