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My A3 Quattro

sparrow Aug 29, 2015

  1. Prawn

    Prawn My other car is a MINI!!!!

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    rear springs at 18kg are 1008lb.

    Given the rear motion ratio on the 4wd shell of 0.63 that gives you effectively a rate of 635lb on the rear.

    Actually not that daft. Especially not considering an 800lb front spring.

    80mm long sounds MEGA short though, and would surely be coilbound too easily with any form of compression.

    Also 800 front sounds too hard to me.

    I'm currently on 550lb front and rear, with a rear MR closer to 0.9 giving an effetive rate of 500lb at the rear wheels.

    What rear roll bar is on the car? what front bar?

    It certainly sounds like it's **** currently, and Spires CERTAINLY know their stuff! I'll be very interesting to see how they transform the car for you!

    As an aside, I'd be very interested to hear what sort of ball park figure they charge for a service like that, checking, advising, setting up ETC. PM me if you'd rather not disclose!

    Can't wait to hear the news that it's all sorted and driving beautifully :racer:

    When does it go back to Gloucester to be tuned further?
     
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  3. sparrow

    sparrow Registered User

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    All being calculated properly this time, with corner weight scales, the lot. :)
     
  4. sparrow

    sparrow Registered User

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    80mm is the right length, with 100mm it was impossible to get the ride height down properly at the back:
    [​IMG]

    This is them:
    [​IMG]

    80mm/0.63 = 130mm of wheel travel, plus droop from the helper springs.

    Roll bars are not standard, they are H&R so I guess 25mm Front and 21mm rear, but I'll measure them. The rear looked really chunky. Rear will be disconnected to start with.
    I'll let you know the final cost once it's done. Matt (and Dave when he was there) really do know their stuff. I'm lucky to have someone that good 5 minutes up the road.

    As for further tuning, it's safe and quick enough for now, so no rush to get it back. Would rather get the mechanics sorted, and then wind it up later.
    At the rate I'm going, I might even have the rolling road in before the car's finished!
     
  5. sparrow

    sparrow Registered User

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    Time to get up to date.

    After a few email conversations with Matt, things progressed.

    Matt weighed the car, and it is currently 1096kg, 687kg at the front, 409.6kg at the back. So 63% at the front, 37% at the rear.

    The fronts were almost identical to the originals, slightly softer, but also slightly longer.
    The rears were MUCH softer. I will admit, I was skeptical at this point, they seemed too soft, based on what everyone else was running.
    However, Matt will have forgotten more than I'll ever know about suspension, so went with it.

    When the new springs arrived, Matt found the rears were to short. Matt quickly realised why.
    With the old hard springs, the rear of the car was only compressing the springs 3mm! No wonder I was struggling.
    This explained something else, as shown above. When the KWs were first fitted, the rear was far too high. No wonder, when the correct spring rates were fitted, the car settled much more.

    Corner weighting was also done, with a perfect 50/50 diagonal set up achieved.
     
  6. sparrow

    sparrow Registered User

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    Next up, noise reduction.
    I'd supposedly hit 108dB on drive by at Donington. While that's very unlikely, the car was loud.

    Thanks to yoof, who put me in touch with a contact of his, I had a repackable silencer made up and sent over.
    I dropped the car off at Stealth to get it fitted. Unfortunately my measuring was less than ideal (OK, it sucked), so the silencer didn't fit where I wanted it.
    Stealth did the best they could with what I'd provided, but had to modify it to make it fit. As always, they did a fantastic job.

    This meant the car was ready, but I had no usable treaded tyres. The AO48s resembled 50p pieces after Donington.
    I decided to treat myself to a new set of boots, but couldn't justify new DZ03s or the new AO52s, so went with some R888Rs all round.
    I managed to get them fitted on Saturday morning, which meant I could book on a track day with some confidence. Not much, but more than before.
     
  7. sparrow

    sparrow Registered User

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    So, to Bedford we go. All ready:
    [​IMG]
    I set off in torrential rain. Perfect weather for a first test of brakes and suspension. Not.

    Nothing I could do about it, so I got there, signed on and went for noise testing. 96dB/97dB, the same as my noise meter I'd bought. Higher than I'd like, so I'll have to look at that again.

    After drivers briefing, I went over to the pits, unpacked and went on the sighting laps.
    Which immediately raised an issue. I have no demister.2 slow laps, and I couldn't see where I was going. I need to order some RainX.

    I did some brake tests, and was able to modulate well enough, but it was very slippery. This also meant I was able to test the traction control, which worked well.

    I came in, wiped down the interior, and propped open the passenger side window half an inch.
    Back out, and this worked well enough. I did a few laps, exploring the conditions, working out where the grip was, and where I could brake. I spent most of the day braking far too early, but wanted to drive it back on to the trailer.

    First impressions.
    Matt at Spires knows suspension. The car behaved exactly as I'd asked him for. It's neutral, but I can induce the rear out if I want to.

    This thing is ludicrously fast. It was too fast for the conditions today. I managed 130mph at half throttle!
    [​IMG]
    The bottom graph is the traction control working. That's a pull down the back straight, from second to sixth. Yes, the traction control is stepping in at 120mph in sixth over the bumps! :p

    The traction control works really well. As it was wet, I've set it to be super restrictive. I was able to roll on to the throttle, looking for the limit of adhesion.
    However, when it broke traction, instead of having to get out of the throttle again, I simply held it and let the ECU keep things under control.
    Then repeat until I had to brake for the next corner.

    Mid corner traction was immense. I could barely get the tyres warm, but never really felt short of lateral grip. If the rear started to go, it gave plenty of notice, and was easy to control.
    The front was rock solid on turn in, and coped with the power well on corner exit. The traction control obviously helped.
    I was even able to lift mid corner when someone spun in front of me, without any real drama.

    Braking was a little trickier, but a large part of that is me still getting over the previous issues. The good news is the fronts now lock before the rears. A cone is testament to this.

    I managed 4 good sessions this morning, and wasn't passed once. I passed quite a few others, so was happy enough with that.
    I ended up leaving at lunch time to get back to the office.

    I'm hoping to get to Rockingham this Sunday, as the sprint series I'm entering has it's first meeting of the year there on the 25th.

    Future Plans
    Redo exhaust system so that I can do some proper testing at a track day. Although I'm probably OK for most tracks now, I'd like a safety margin.

    I want to do some proper driver training, so I can start to use the potential of the car, and learn more.

    I need to get the cage redone, as Bill has condemned this one.

    I have an SQS Shifter, which will allow clutchless upshifts in conjunction with the ECU.
    If I'm also able to fit our E-Shift unit, I'll have clutchless up and down shift via paddle shifting. Otherwise I still have the MME pneumatic system, which will give me the same.
     
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  8. sparrow

    sparrow Registered User

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    Scanning through the logs for work related, I spotted something that's given me some more confidence in the brakes.
    I locked up twice under braking in the log I was looking at. On both occasions, only the front wheels locked, never the rears.

    [​IMG]

    [​IMG]
     
  9. Prawn

    Prawn My other car is a MINI!!!!

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    Great stuff Alex! I'm so glad it all seems to be working well for you.

    Glad to hear my brakes are doing a good service elsewhere too. That traction control and logging system looks absolutely awesome too! very jealous of that.

    Look forward to hopefully seeing you and the A3 at Curborough this year or another track day!
     
    sparrow likes this.
  10. sparrow

    sparrow Registered User

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    It's off for it's new cage:

    [​IMG]

    Hopefully back at the end of next week, along with the new perspex windows from @StaceyS3
     
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  11. Prawn

    Prawn My other car is a MINI!!!!

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    Exciting stuff Alex!

    Who's doing the cage?
     
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  13. sparrow

    sparrow Registered User

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    James Winter, as recommended by @badger5
     
    Prawn likes this.
  14. sparrow

    sparrow Registered User

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  15. badger5

    badger5 www.badger5.co.uk Site Sponsor

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    thats better
     
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  16. sparrow

    sparrow Registered User

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    Slow progress, but progress. The cage is now painted, so refitting everything. Wiring is back in and the car runs.

    [​IMG]

    A bit of coil pack bling, plus it fills the gap between the coils and rocker cover:

    [​IMG]

    I need a new windscreen as the original broke when the cage came out. Just waiting for the window guy to get one.
    I also have perspex windows to fit. Currently doing the door windows, and will then fit the doors once the windscreen is in.
    The window guy will do the rear perspex screen at the same time.
    I need to do some work on fitting the rear 3/4 windows, as the car had pop out windows. I've binned the mounts for those, and will just trim these to fit, and then need to secure them somehow.

    I have the fittings for the fuel pressure sensor as well, so will also fit that.

    I have all day Sunday on it, so hoping to have everything bar the windows done, so I can book a test day as soon as they're in.
     
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  17. sparrow

    sparrow Registered User

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    Time to bring this up to date.

    It looks like a car again, if somewhat dirty (works in the unit created a lot of dust):
    [​IMG]

    Plex Knock Monitor installed:
    [​IMG]
    I still need to finish the last bit of the set up, but that has to be done on the dyno, as I need a full run through the RPM range with no knock.
    It currently thinks I have knock at idle because I haven't set that up yet.
    I've connected both knock sensors, but only using one for now. I can easily change that.

    Wiring is also in for the fuel pressure sensor, but I haven't fitted the sensor in to the fuel line yet, as I ran out of time. I just need some hose clips.

    Off to @badger5 tomorrow for mapping, although it's supposed to be 30 tomorrow, so not sure how much we'll see. Hopefully we'll have time to fit the fuel pressure sensor.
     
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  18. Prawn

    Prawn My other car is a MINI!!!!

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    I wouldn't worry too much about the heat. it's better to have it mapped in the heat then you know it's safe for any conditions.

    Mine was still doing 475+ at low boost in 30 degree + temps. yours should be capable of similar I'd think if not more :)

    Great update Alex. I'd missed the last one. Not heard of the Plex monitor either. Are there any plans to get knock detection on board with DTA?
     
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  19. sparrow

    sparrow Registered User

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    It's not too hot, so that's OK.

    Yes, hardware update next year, which will include onboard knock.
     
  20. sparrow

    sparrow Registered User

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    Yay:
    [​IMG]

    :angry:
    [​IMG]

    Gearbox flange is loose. Looks like SQS didn't tighten the bolt.
     
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  21. Prawn

    Prawn My other car is a MINI!!!!

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    Nice one Alex!

    It gets going early doesn't it!

    How did you find that loose output flange? Did it manifest as a vibration?
     
  22. sparrow

    sparrow Registered User

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    Thanks Nick, I'm pleased, especially as IATs were 50C!

    Yes, very early. 1 bar boost by 3750RPM, peak of 30psi at 6000, and still has 26psi at the 8300 rev limiter.

    There was no indication of the loose flange on the dyno, which is kind of good news. When we pulled the car off Bill found all the oil at the bottom of the dyno.
    As there's no oil on the unit floor this morning, that means it's all still at Bill's. It was doing 150mph just before we pulled it off they dyno, probably with no oil.
    However, there were no noise or issues, so it must have happened at the end of the day, otherwise the gearbox would have killed itself with no oil.
    I'll speak to Vince as he's just down the road, and see what he says.
     
  23. scotty_24

    scotty_24 Registered User

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    Excellent result! She's gonna fly
     
  24. sparrow

    sparrow Registered User

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    Thanks.

    Spoken to Vince, and he's said internals are most likely fine. However, the bolts don't normally come loose, the normally shear.
    So I'm going to drag it off the trailer today, and see if I can find an hour to pull that out.
    If not, I'm on holiday next week so it will have to wait until I'm back.
     
  25. sparrow

    sparrow Registered User

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    Good news - the bolt had come loose.
    Seal seems fine, so refitted it. Just need some gearbox oil now.
     
  26. Prawn

    Prawn My other car is a MINI!!!!

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    Perfect! Great news mate.

    I meant to ask before, do you have water meth?
     
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  27. sparrow

    sparrow Registered User

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    No water meth. @badger5 was twisting my arm while I was there.
    However, 50 degree IAT and 20 something timing, I'm happy for now.
    If I change my mind, I'll look at the IO I have left, and see if I can run it from the ECU.
     
  28. badger5

    badger5 www.badger5.co.uk Site Sponsor

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    good news.
    simple fix
    and water meth... you know you want to :p hehe
     

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