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Orthojoe's track build journal

 
Old 02-18-2018, 08:47 PM
  #1891  
na94
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I spent yesterday prepping my .1 GT3 for track work, but I skipped out on adjusting corner weights.

The alignment hoist I used is a 4 post with 2 rolling jacks. I can jack the exposed rear cross member in order to fit the scales below the vehicle, but I am unsure where to jack the front up from. The rolling jacks aren't wide enough to engange the usual lift points. Is there a front cross member under one of the underbody trays that I can use?

Also, how can I remove the front brake ducts to simplify toe adjustment? Adjusting front toe is a major pain with those on there, but I didn't want to snap the tabs off them in an attempt at removal.
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Old 02-23-2018, 01:40 PM
  #1892  
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I already posted in another thread but I think it s more appropriate to continue that on a specific thread that talk about track use

Anyone is using the ferodo racing ds 1.11 brake pads?

I fitted them on my 991.1 gt3 and I did the bedding in procedure and even if they perform really well on track as soon as I m on the street with light braking they make some abrasive noise a little similar as when a pad is completely worn and they seem to be quiet agressive on the rotors

It was suggested that maybe the bedding procedure was not ok and that the pad material didn t transfer well on the rotor wich I think is completely possible but I tried to do the bedding a second time and did a second trackday but the noise is still the same so I would like to understand if it s the pad material

and it s normal or if it s the bedding that wasnt ok

The pads do not squeal at all it s just a slight sandpaper type of noise
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Old 02-23-2018, 03:00 PM
  #1893  
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Originally Posted by Manifold View Post
IMO, it's a really bad idea. It's a good recipe for creating a car with balance which varies unpredictably within sessions and across sessions.
Why would this be? It would be another variable in your set up potentially, but I don't see how it would be any more unpredictable than having the same tires front to back. If one has better cold grip for example, you note that and change your driving style/set up around it.
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Old 02-23-2018, 04:27 PM
  #1894  
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Originally Posted by misterwaterfall View Post
Why would this be? It would be another variable in your set up potentially, but I don't see how it would be any more unpredictable than having the same tires front to back. If one has better cold grip for example, you note that and change your driving style/set up around it.
The behavior of a tire isn't a constant during a session, it varies as the tire pressure and temp changes. The nature of this change could be quite different from one tire to the next, with some tires taking less or more time to develop grip, get greasy, etc. Tires can also vary a lot with respect to how they change as they accumulate heat cycles.
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Old 02-23-2018, 05:36 PM
  #1895  
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Originally Posted by Manifold View Post
The behavior of a tire isn't a constant during a session, it varies as the tire pressure and temp changes. The nature of this change could be quite different from one tire to the next, with some tires taking less or more time to develop grip, get greasy, etc. Tires can also vary a lot with respect to how they change as they accumulate heat cycles.
The same is already true for front/rear tires even of the same make and model though, so these variables aren't really any different. Your front and rear tires will build heat differently, will wear differently, and act differently throughout the session. You make changes, add wedge/pressures ect to get around this.

You could take it a step further and say that you must always have the same make/model of tire with the exact same level or wear and number of heat cycles. This still wouldn't mean that they get up to temp at exactly the same time, wear exactly the same, and lose grip at exactly the same time.
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Old 02-23-2018, 06:14 PM
  #1896  
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Originally Posted by Maxi_z View Post
I already posted in another thread but I think it s more appropriate to continue that on a specific thread that talk about track use

Anyone is using the ferodo racing ds 1.11 brake pads?

I fitted them on my 991.1 gt3 and I did the bedding in procedure and even if they perform really well on track as soon as I m on the street with light braking they make some abrasive noise a little similar as when a pad is completely worn and they seem to be quiet agressive on the rotors

It was suggested that maybe the bedding procedure was not ok and that the pad material didn t transfer well on the rotor wich I think is completely possible but I tried to do the bedding a second time and did a second trackday but the noise is still the same so I would like to understand if it s the pad material

and it s normal or if it s the bedding that wasnt ok

The pads do not squeal at all it s just a slight sandpaper type of noise
What you are describing is normal after a track day. The scrape/grind goes away with some street driving. This has happened with every pad compound i've used on track.
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Old 02-23-2018, 06:22 PM
  #1897  
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I didn t get that kind of noise and visual abrasive rotor wear after just a few sessions on other pads as pagid rs29 or rsl1

I think that for some reason during bedding the layer of pad material did not went correctly on the rotor surface but I dont know why

But I also think that some normal road use will make things better
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Old 02-23-2018, 06:39 PM
  #1898  
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Originally Posted by misterwaterfall View Post
The same is already true for front/rear tires even of the same make and model though, so these variables aren't really any different. Your front and rear tires will build heat differently, will wear differently, and act differently throughout the session. You make changes, add wedge/pressures ect to get around this.

You could take it a step further and say that you must always have the same make/model of tire with the exact same level or wear and number of heat cycles. This still wouldn't mean that they get up to temp at exactly the same time, wear exactly the same, and lose grip at exactly the same time.
Sure, but the differences are likely to be bigger when you're mixing different tires. I haven't found the balance of my GT3 to change much within and across sessions when using the Cup 2 front and rear, except that the car would tend to get a bit looser when the rear tires reached their heat cycle limit, so the rears seemed to cycle out a bit sooner than the fronts. At that point, I'd just replace all four tires.
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Old 08-14-2018, 08:02 AM
  #1899  
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I can't see the pics / links on messages 747 and 748 on this thread. Are they still available?

Thanks
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Old 08-14-2018, 10:56 AM
  #1900  
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Originally Posted by NotThatFast
I can't see the pics / links on messages 747 and 748 on this thread. Are they still available?

Thanks
Sorry, man. The host site must have timed out the pics from over 3 years ago and I don't have them anymore.
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Old 08-14-2018, 11:22 AM
  #1901  
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Ah! thanks for checking othojoe, I appreciate.

Any chance someone can opine on how legit/safe it is to attach the harness to the seat rather than the tub of the car? I think that you used the GMG plate for the sub-mount bar, but now the likes of canterell offer a bar that attaches to the bottom of the seat which means sub-mounts and lap belts can be mounted to the seat.

I am asking as I have to decide where to attach the harness for my GT3.2. The OEM Clubpsort mounts to the tub, but that means drilling and cutting carpets for my car. And since part of the 3 point is attached to the seat, maybe attaching the harness to the seat is acceptable (?)
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Old 08-14-2018, 12:03 PM
  #1902  
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most DE cars have harness attached to the seat primarily to avoid cutting.
if prolly safer than not having harness at all
but all race cars have them bolted THROUGH the tub with large plates. that is the safer than bolting to the seat. but you will be hacking up your car.
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Old 08-14-2018, 12:28 PM
  #1903  
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On the lightweight buckets the stock lap belts attach to the seat so the seat is probably a relatively safe place to attach. The sub straps are there only to keep the lap belts low on your hip bone so you don't slide down and have the belts cut you in half through the abdomen, so they don't bear the major stress in an impact.
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Old 08-14-2018, 12:52 PM
  #1904  
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Originally Posted by NotThatFast View Post
Ah! thanks for checking othojoe, I appreciate.

Any chance someone can opine on how legit/safe it is to attach the harness to the seat rather than the tub of the car? I think that you used the GMG plate for the sub-mount bar, but now the likes of canterell offer a bar that attaches to the bottom of the seat which means sub-mounts and lap belts can be mounted to the seat.

I am asking as I have to decide where to attach the harness for my GT3.2. The OEM Clubpsort mounts to the tub, but that means drilling and cutting carpets for my car. And since part of the 3 point is attached to the seat, maybe attaching the harness to the seat is acceptable (?)
I would go with the bars that attach to the bottom of the seat. Installation is much easier. The GMG is more involved and it doesn't slide with the seat when you move it back and forth. Also, on the passenger side, the hardware can catch and tear the tubing for the seat occupancy detector when you move the seat up/down forward/back. Keep it simple and go with the Cantrell seat bar.
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Old 08-16-2018, 01:12 AM
  #1905  
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Thank you for your feedback in particular the part about the electronics under the passenger seat which I was not aware of. I agree with CobaltCr that if the attachment to the seat is good enough for the stock 3 point then it should be ok for my purposes to attach the 6 point to the seat. I wonder if anyone in the US (none of your cars are clubsport equipped so the largest community facing these challenges) has gone through the hassle of attaching the lap belts to the tub of the car (reinforcement plates installed properly, cut carpet etc)
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