Question on period brakes

[NZeder]

Guys I have a question for all those that know the answer,

 

if you don't want to publish the info on the forum please PM me that answers to what I seek.

 

First the reason for this post.

 

Our local race rules are changing and there currently are interpretation issues. But to cut to the chase if I can prove a setup was used in any racing during the period I can run with this setup on the car.

 

The period is 1969-1977. And the car is the S30 range. I already now the stock setup can work with maintenance and correct pads/cooling etc - however I would like to fit the largest period correct setup I can.

 

So this is what I know.

 

Stock are 271mm x 12.5mm solid with twin piston caliper

FIA options were 4 pot MK63 calipers in two types - one for the stock rotor the other for a vented rotor that was close to the stock sizing but 20mm thick (this is a close fit to the toyota/300zx hybridz setup)

 

I know what the FIA Group 4 rules allowed and most cars during this period followed these rules and that was max 12" rotor with calipers/pads free (not sure on the thickness)

 

What I want to know is what sizing was used in other classes ie SCCA C/Production etc.

 

Looking at the "How to HOTROD and RACE your Datsun" in the rear is a list of the partnumbers for options that were available from "Datsun Competition Department" and there is a listing for the "H/A 4-wheel disc brake kit" however I would like to know what size this is. The front and rear share the same rotors so I assume these were just parts from another supplier ie AP/Lockheed of the time not a Nissan part at all but something "Datsun Competition put together and added to an options list for racers of the day.

 

So can anyone tell what other sizes were run in the period - also if you have any period documentation that I can use that will also be helpful when I complete my documentation locally.

[johnc]

Here on the west coast of the US the vintage groups are allowing the 4 piston iron front calipers with a 11 to 11.5" vented rotors and a single piston iron rear caliper with a solid 11" rotor. Its the closest we can get to the FIA approved setup using available parts and is close to what was run in SCCA CP during the later 1970s.

[CArFAn]

The title of this thread is just wow. Sorry i cant help out.

 

-Carfan

[29PGC10]

One of the cars taking part in Springbook series in South Africa during 1973 (RF100) had MK63 in the back as well. Those cars were to FIA spec. Martin

[HS30-H]

Our local race rules are changing and there currently are interpretation issues. But to cut to the chase if I can prove a setup was used in any racing during the period I can run with this setup on the car.

 

The period is 1969-1977. And the car is the S30 range.

 

Mike,

What's the local situation with wheel diameter? They are letting you run 15" - yes? I think the only limiting factor you'll have on your brake rotor diameters will be the insides of your wheel rims.......... !

 

As far as radical brake setups *pre-'77* goes - the sky's the limit. I can provide you with evidence of inboard rear discs and MK63s in use pre-'73 if you need it.....

 

 

 

One of the cars taking part in Springbook series in South Africa during 1973 (RF100) had MK63 in the back as well. Those cars were to FIA spec.

 

Hi Martin, how are you?

One of the cars was running in Group 4 ( E4621 'Safari' head on injection and local drivers ), and the other one ( with the injected LY and the Japanese drivers ) was running in Group 5 - am I correct?

 

Can I ask, did the document come via Mr v.B, and is that Wakabayashi san's or even Nanba san's handwriting, do you think?

 

Best regards,

Alan T.

[NZeder]

First thank to all for the replies/post this is the kind of info I am after.

Mike,

What's the local situation with wheel diameter? They are letting you run 15" - yes? I think the only limiting factor you'll have on your brake rotor diameters will be the insides of your wheel rims.......... !

 

As far as radical brake setups *pre-'77* goes - the sky's the limit. I can provide you with evidence of inboard rear discs and MK63s in use pre-'73 if you need it.....

 

Best regards,

Alan T.

Hi Alan, yes 15" are permitted and we are currently finding out if 16" are also permitted. The rules state rims should be period looking (so just about any minilite replica is good) and have a min aspect ratio of 50 but there no statement about rim size. I know that during the mid 70's some Porsche's were running 16" so if they can run them we should be able too also.

[29PGC10]

Alan, that is quite correct. The 'locals' (Arnold Chatz & Geoff Mortimer) had G4 car - HS30-01820.

The Japanese - Kenji Tohira & Kunimitsu Takahashi - used 'protorype' - hence G5? - HS30-10903, 260Z but running with L24 engine.

 

Regarding the document, while I was scaning EvB photos & newspaper cutings I came across this page. I dont know who was responsible for the cars preparation from Japanese side. Ewold was runing the team while in South Africa, while Satoru Shinoda was 'chief mechanic'.

 

Regards,

 

Martin

[260DET]

................

 

......................................................... I know that during the mid 70's some Porsche's were running 16" so if they can run them we should be able too also.

 

So to clarify the situation, are you inquiring as to what S30's used or other cars as well? Because Porsche used all sorts of 'big stuff' and if you could copy them.................

 

In AU Porsche can use all sorts of 'big stuff' which other cars can't

[NZeder]

So to clarify the situation, are you inquiring as to what S30's used or other cars as well? Because Porsche used all sorts of 'big stuff' and if you could copy them.................

 

In AU Porsche can use all sorts of 'big stuff' which other cars can't

You are correct I am looking for a S30 running 16" in the period that my car will be classified under 1969-1977