Jump to content


Photo

Group Sc Brake Problems


  • Please log in to reply
48 replies to this topic

#21 260DET

260DET

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 2,223 posts
  • Location:Warwick
  • Tagline:Tribal Elder

Posted 06 May 2015 - 11:09 AM

This should not be a pissing match Jason, it's intended to provoke constructive responses and to get a bit of thought going. I'm not the one claiming that because of inadequate brakes the S30 is uniquely handicapped when it seems pretty obvious that all Sc cars would have to face the same problem.

But if you want to get personal then I'll fire just one point back, one out of many. Brake pads. Obviously it's nonsense to claim in effect that there are no suitable pads available. Utter nonsense.



#22 d3c0y

d3c0y

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 2,906 posts
  • Website:http://garagesanmaru.com
  • Location:Brisbane
  • Tagline:Forum Jerk

Posted 06 May 2015 - 11:32 AM

I've been intently reading, but don't feel i have anything constructive to add, but do find the topic interesting.


Could you make a thicker rotor that would have more meat and be less resistant to cracking?

#23 1600dave

1600dave

    Senior Member

  • Members
  • PipPipPipPipPip
  • 607 posts
  • Location:Newcastle,NSW

Posted 06 May 2015 - 12:10 PM

Nope, rotors must be 100% standard.

Wheels too - strictly speaking, they must be "period correct" (although that rule seems to be more loosely applied from my observations at Group S meetings). A modern style wheel that aids cooling may well be knocked back as being not eligible. Agree with your statement that the best wheel should be chosen from those that are eligible.

My 2c (from one who has never competed in Group S but has flag marshalled at a lot of historic meets where Group S run, compete at some of the same events as Group S and have a Group S build on the go - well, I will have once I find that enthusiasm and spare time I hid away in the shed somewhere....)

I think the quote on driving style is the most telling bit of this thread. Group S is designed to emulate production sports car racing back in the day (when even the top cars in the biggest event on the calendar, the Hardie Ferodo 500, would run out of brakes - cue the development of HO Falcons / RT chargers / Bathurst special Monaros to get better "race" parts homologated for the track). Back when, arguably, driver skill counted for more, or they had more to deal with and overcome (like dodgy brakes). You could allow freedoms in Group S for the zeds so they can stop better, but then where do you stop (hehe, I made a funny - where do you "stop".....) with regards to "parity" ? Allow bigger brakes for zeds, they can now compete with (or even beat regularly) the Porsches. Then the Porsches complain, they get bigger brakes, and so on.

Arguing with CAMS that factory / possibly factory fitted competition parts should be allowed is one thing, but allowing access to more modern / better performing alternatives is (in my mind anyway) quite another. Group S is for drivers to compete in cars representative of the period, and may not be the best category for the driver who wants to compete in his favourite type of car - to win at all costs, ideally you would pick the most suitable car and develop that (whether that's a Datsun or a Porsche). I'm probably an example of this, my intention is to join Group S in a Fairlady. I have checked things out and will be going with a 1600-engined one, rather that the much faster and (on the face of it) more suited to racing U20-engined one. Running a U20 puts me into a faster, more serious category with Porsche, Corvette, Healeys, etc. So, stick with the 1600 and play with MG's and the like. I also was looking at building up a 1600 sedan for Group N, but the additional freedoms allowed in that category, including brakes (and their propensity to drive more aggressively / cop more panel damage) is what made me lean to Group S.

I take Jason's point about the lack of brakes potentially being unsafe, but then again "Motorsport is dangerous" (so the back of the tickets, the entry forms, etc, all tell me). The answer may well be that if zeds are unsafe, get a different type of car that is safe - the event isn't a category for Datsuns, but for the production sports cars.

Personally, I like the category. It offers good, close (but mostly clean) fun. Some of the top cars are punted around extremely quickly for what are essentially only lightly modified versions of the road car. It is good to consider how to improve things, but keep in mind that production sports car racing has been around long before Group S, and that even Group S has some highly developed cars with very quick drivers.

#24 hmd

hmd

    Advanced Member

  • Members
  • PipPipPip
  • 300 posts
  • Location:Melbourne Easts

Posted 06 May 2015 - 12:44 PM

Personally, I like the category. It offers good, close (but mostly clean) fun.


Dave,

You will enjoy Sb with 1600 roadster.

#25 hmd

hmd

    Advanced Member

  • Members
  • PipPipPip
  • 300 posts
  • Location:Melbourne Easts

Posted 06 May 2015 - 12:47 PM

This should not be a pissing match Jason


You two need to get a room  8)

#26 1600dave

1600dave

    Senior Member

  • Members
  • PipPipPipPipPip
  • 607 posts
  • Location:Newcastle,NSW

Posted 06 May 2015 - 03:22 PM

Dave,

You will enjoy Sb with 1600 roadster.


I've been thinking / planning for a few years. Had the cars for many more years and been acquiring parts since then. All that's left to do is build it.  :-[



You two need to get a room  8)


"Two men enter, one man leaves" ??

Posted Image



#27 dat2kman

dat2kman

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 4,061 posts
  • Location:Newport Waters Qld
  • Tagline:going sailing, see ya later!

Posted 06 May 2015 - 06:21 PM

We're a tiny bit more civilised than that.
As a FYI,, the other Gp S cars that the Dato Z's are up front with are running four wheel discs, and ventilated.
They do not have any overheating concerns, unlike the solid rotor front/drum brake rear Z's that are mxing with them.
We have come up with a vented rotor, same OD as stock, and a modification/addition, to the stock caliper, that will straddle the rotor.
We dont have a major issue woth pads, and are using various top f range  froction co- efficient pads,,, it is the heat build up in the rotor, hib, wheel centre and caliper, that causes the issue.

#28 JIM71Z

JIM71Z

    Member

  • Members
  • PipPip
  • 19 posts
  • Location:Northern Beaches, Sydney
  • Tagline:New Member

Posted 06 May 2015 - 08:22 PM

Gday Guys,
Just thought I should poke my nose into the conversation. Having raced GpS for a few years now, I have found by using quality rotors, Brembo, and Pagid RS4 for sprint races 30km and Pagid RS29 for our 100km race have worked ok. However, if I just pull into the pits after a race the rotors will warp. I must stop the car on the clutch so not to clamp the pads to the rotor, and jack up the car and keep turning wheels until they cool down to a point where they won't warp. You also need to make sure your rear brakes are adjusted up for every race. Less load on front brakes = less heat. I will also bleed the brakes once or twice over a weekend or as required. Up until now I have been using Castrol SRF but am trying a new combo at the moment. If you don't warp a rotor you will get up to 4 meetings out of a set of pads and rotors. The rear shoes will only last 2 meetings but at $30 who cares, as long as you don't trash your drums. I have tried trick drum linings but don't work. Unfortunately after 4 race meetings the rotors are no good any more as they will be bent not necessarily warped. The friction faces will look great but if you put a straight edge across the back you will notice the outer edges of the rotor will be bent inwards. this is caused by the "ring" of extreme heat and the much cooler hub area. If you machine them you would loose about 1.5mm off thickness but am more worried about shattering one in use as they try to bend again.  If you fit new pads they will need to bed in to a taper to conform and create loads of pad knockoff. Also If you race in the rain and go through a puddle you will warp a rotor.
Over the years I have had many success and failures and still I have to keep developing the car. My current problem is I am on my last set of Brembo rotors and they are no longer available worldwide. I have been in contact with RDA who told me there product was not suitable for racing.  Where to now? Chinese rotors??? also drums haven't been made for years. Chinese drums are hopeless and dangerous. My car hits 220 down the straight at Eastern Creek and is a big stop into turn 2. Will they work lap after lap?
I like the concept of the GpS rules, and don't like watering them down, but our cars have come a long way since the rules were written. While running std SUs it made us make them work instead of just bolting on some Webers Mikunis etc. With the brakes its the same theory, but when suitable safe parts aren't available???
  I would like to see a vented rotor off a Peugeot or similar allowed with a spacer of about 8mm or so in the caliper but getting this through CAMS might not be so easy. I think it would be safety issue if we were to run sub standard parts.
  Where do we go from here?
James

#29 JIM71Z

JIM71Z

    Member

  • Members
  • PipPip
  • 19 posts
  • Location:Northern Beaches, Sydney
  • Tagline:New Member

Posted 06 May 2015 - 08:30 PM

and also don't worry about the Porkers with there 4 wheel discs The Zeds have L series power. Just blow em off down the straights n hold them up around the back  ;D

#30 hmd

hmd

    Advanced Member

  • Members
  • PipPipPip
  • 300 posts
  • Location:Melbourne Easts

Posted 06 May 2015 - 10:29 PM

My current problem is I am on my last set of Brembo rotors and they are no longer available worldwide.

  Where do we go from here?
James


James,

Apparently tirerack still sell them

http://www.tirerack....74&autoModClar=



#31 1600dave

1600dave

    Senior Member

  • Members
  • PipPipPipPipPip
  • 607 posts
  • Location:Newcastle,NSW

Posted 07 May 2015 - 12:26 AM

And drums are available as well (not sure if these are the Chinese ones you speak of though)

http://datsunparts.com/Brakes

#32 260DET

260DET

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 2,223 posts
  • Location:Warwick
  • Tagline:Tribal Elder

Posted 07 May 2015 - 08:06 AM

Good to see some positive comment particularly concerning brake management, to provoke constructive discussion was the whole idea of this thread :)

StopTech in the US sell S30 front rotors and their gear is good, while on the subject of the US I'm fairly sure that the well known early racing successes of the S30 there included the SCCA C/production class which if I'm right was allowed some engine but no brake upgrades. And now moving to the subject of upgrades, it may be said that we are fortunate in being allowed to use the current front and rear aero, as far as I'm aware the front spoiler was never a production item.

#33 hmd

hmd

    Advanced Member

  • Members
  • PipPipPip
  • 300 posts
  • Location:Melbourne Easts

Posted 07 May 2015 - 10:09 AM

Freight from US for these heavy parts are killers.

#34 dat2kman

dat2kman

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 4,061 posts
  • Location:Newport Waters Qld
  • Tagline:going sailing, see ya later!

Posted 07 May 2015 - 10:33 AM

Freight from US for these heavy parts are killers.

Yes, yes it is!

It may pay for a number of us to get together and do a bulk purchase, and get them sent via Sea Freight

#35 dat2kman

dat2kman

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 4,061 posts
  • Location:Newport Waters Qld
  • Tagline:going sailing, see ya later!

Posted 07 May 2015 - 10:46 AM

Good to see some positive comment particularly concerning brake management, to provoke constructive discussion was the whole idea of this thread :)

StopTech in the US sell S30 front rotors and their gear is good, while on the subject of the US I'm fairly sure that the well known early racing successes of the S30 there included the SCCA C/production class which if I'm right was allowed some engine but no brake upgrades. And now moving to the subject of upgrades, it may be said that we are fortunate in being allowed to use the current front and rear aero, as far as I'm aware the front spoiler was never a production item.

Excellent work, to see you have solved our braking concerns!
And now on to solve our "aero"!
What is specified in the CAMS Group S specs sheets along with the FIA Homologation papers, in conjunction, as what is permitted.
Noting some items are valid/invalid for PRC. ( Austrlian Rally only from 1988 onwards, we built a 260Z that complied, and eventually won the NSW State Rally Champs)

It matters not that the Aero were never a "production" item, the front/rear spoilers were applied for many many years ago, based on the mid 1970's useage of these items on the then Production Touring Cars, at the time, only here in Australia, it was this that got them accepted, and only certain specific designs and sizes.

#36 hmd

hmd

    Advanced Member

  • Members
  • PipPipPip
  • 300 posts
  • Location:Melbourne Easts

Posted 07 May 2015 - 12:35 PM

And now on to solve our "aero"!


We should leave this thread as the brake thread?

#37 260DET

260DET

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 2,223 posts
  • Location:Warwick
  • Tagline:Tribal Elder

Posted 07 May 2015 - 07:02 PM

Yep, Jason can start an aero thread :)

#38 dat2kman

dat2kman

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 4,061 posts
  • Location:Newport Waters Qld
  • Tagline:going sailing, see ya later!

Posted 07 May 2015 - 09:31 PM

Yep, Jason can start an aero thread :)

Absolutely pointless!
We know what the requirements are, and work within those!

I have just been sent a whole magazine,Austrlian Sports Car World, 1973, by a member here, Andrew, and it contains fair
Y detailed information in the road registered cars, as built by Nissan, that were sent out here under Carnet De Passage.
This, and further pictures, parts catalogues, and other material, will be used in a submission.
The crucial thing is that we need a letter from Nissan advising that there were a number of cars built, new, that had the items fitted.

It is this detail that will be submitted to CAMS. G
The fact that they were built by the factory, to be registered ( transport approved) on public roads, is sufficient requirement, as advised by Bruce Richards.

Alan Thomas, do you have contacts at Nissan Japan?
Does anyone have a possibly sympathetic to our cause, person at Nissan Japan?

#39 260DET

260DET

    The 2000+ club

  • Members
  • PipPipPipPipPipPipPip
  • 2,223 posts
  • Location:Warwick
  • Tagline:Tribal Elder

Posted 08 May 2015 - 08:13 AM

Let's keep this thread on brakes please Jason, your 'eligible parts' thread is right below.

#40 HS30-H

HS30-H

    Senior Member

  • Members
  • PipPipPipPipPip
  • 619 posts
  • Location:London, England, UK.

Posted 08 May 2015 - 06:11 PM

Alan Thomas, do you have contacts at Nissan Japan?


Yes I do, but in this particular case I recommend you start at the front desk and let them guide you through the system to the person they think will be most qualified and authorised to deal with the request. Short-circuiting the system can be a hindrance.

If it's really as simple as getting Nissan to testify that they built and used such cars (something that we already know, and something that could be demonstrated in any number of ways - including the period Australian magazine articles) then it should be pretty easy... 








0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users