Gr 4 Z

[z-spec]

hello guys , I am building a fia gr4 240z and preparing the shell at the moment and sorting out the suspension , we also are making a 5 speed dogbox straitcut closeratio kit for the T5 gearbox , I have pictures about the project shortly , any help and information is welkom .

[speedshot]

Hello Adrian,

Congratulations. It will become a great car.

Cause you are building a FIA Group 4 car I hope you can give some advices according the homologation papers to me. And may be this will be interesting for you, too.

I have the homologation 3023. After a while of planning how to build the car and after looking for parts, I recognized that there are two versions existing. The one I have got has several Group 4 parts marked and there is another version without marks. I´m not able to explaine the reason for the marks in my Homologation papers by myself. First I thought some of the Group 4 parts are simply marked to show clearly that they are only for Goup 4 use. Then have got in mind they might be generally restricted and this would force me to cancel my Group 4 project.

Now I have asked the DMSB, the German Motor Sports Federation which is an ASN of the FIA and who has sent the papers to me. The answer was that my version is the official and right one. After the DMSB has had correspondence with the FIA in Paris themselves, I have got the information that the marked parts where prohibited after period H2 (Appendix K) and that they are not permitted with year 1976 or later. For example the fibreglass bonnet, doors and tailgate may not be used in a class after 1975. Some mechanical parts like a modified crank (part 12200-N3120) are affected, too. Or the small flares, although the big group 4 flares are not marked and should be allowed.

The DMSB promised me to send a written confirmation to my attention after they have got the official confirmation from the FIA in Paris about the circumstances. After waiting vainly two month I asked the DMSB again. They did not get the confirmation from the FIA until now. I should phone them again in March.

What do you know about the marked passages in the homologation papers? I have attached an example of two pages from the different papers. It would be great to hear your opinion, because for starting building a Group 4 I have to know which parts are prohibited.

Best regards,

Joris

[Carl Beck]

Hello Joris/Adrian:

My copy looks like this.... This copy was a very old copy... not sure when it was made, but before dry ink photo copies were common.. the originals were very yellowed...

Carl B.

Clearwater, FL

http://ZHome.com

[HS30-H]

Joris,

Adrian might not be able to answer you straight away, as I believe he is away racing in South Africa at the moment...........

I have the homologation 3023. After a while of planning how to build the car and after looking for parts, I recognized that there are two versions existing. The one I have got has several Group 4 parts marked and there is another version without marks. I´m not able to explaine the reason for the marks in my Homologation papers by myself. First I thought some of the Group 4 parts are simply marked to show clearly that they are only for Goup 4 use. Then have got in mind they might be generally restricted and this would force me to cancel my Group 4 project.

3023 includes all of the Group 2 & Group 3 stuff as well, and of course some of those parts were shared with Group 4 & even Group 5. As you have found out, the homologation ran out on some parts in period and were therefore no longer allowed. I think I can see the confusion that this might cause, and it might lead you up the wrong path as far as the build and spec of your car.

However, I think you might be taking somewhat of a wrong approach to this. In most of the events and series that your car will be eligible to race in, it is more important for the spec of the car to satisfy the scrutineers and organisers of the event than the FIA themselves ( and who would interpret the FIA spec anyway? ). You also have to convince your fellow competitors that your car is not giving you an unfair advantage over them!

Most organising bodies will welcome a Group 3, 4 or 5 spec Z with open arms, as it helps to break up the hordes of Porsches and the other 'usual suspects' that make up the majority of the field. They like the variety, so you might find that they are relatively lenient towards you and your car. I think it is the organisers that you need to talk to rather than the FIA, and for most organisers simple proof of 'period use' within the years concerned is enough to keep them happy. I recently assisted in proving period use of 15 inch diameter wheels in FIA-sanctioned events, for example.

To be honest it is sometimes better not to go into fine detail on this kind of subject online...........

Alan T.

[z-spec]

Joris , I wil try to help you , Gr4 regulations ended the end of 76 followed up by Gr B , 1/1/1973 the FIA banned glasfibre parts but if you read Annex K 7.3.7 you can stil use these parts .

Also read the period apendix J , al this information can you find on www.fia.com ( hystoric racing ) .

I can also help you with the homologated parts , we are started now with exact copys of the works glasfibre parts ( bonnet, boot, doors ) .

You can also contact me directly in Nederland , we speak dutch ,english and verry good german . ad@va-motorsport.com and can help you with much more things . Fruendliche Grusse Adrian .

[Bpaccaud]

Hello all!

I build a Gr4 too (this is a student project car, i build this car with my student as i am mechanics teacher) and i ask me the same questions...

i have the 3023 with the mark too... and after reading the differents periode of annexe J i notice that in the 1969 periode (the first Z run in this periode) there are no Gr2 or Gr4 en regarding Brian Long (Datsun z fairlady to 280z book), in page 77 the book explain that in 1970 the car ran in Gr3 and have twin choke solex carburator...and fiberglass bonnet, door and rear hatch, perspex windows like the GR3 permit

In 1972 season, perspex and lighweigt panel were banned in GR3 because of new 1971 appendix J rules (and GR2 and GR4 appears....) read P98

that's why "i think" ;that 3023 documents were modified and to clear the situation in this document ,after 1971 "GROUP 4 only" mark appears on parts that are allowed originaly in GR3

Nowadays FIA technics or not very clear with the History; so things are not clear for us...it's very difficult to know all in all brand...

I have a good friend who is technics for the FIA; and was now specilst in historic racing car; and he tell me that for exemple:

for the breaks: we could'nt find the FIA homologuated calipers for the Z but as we respected the piston dimension to have the same area, and if calipers are pretty the same look (like AP racing 4 piston) "he tell me to machine cut the Ap racing mark"...; technics would'nt be too hard or visiuous to refused the car...

And he tell me to respect the technics conception periode to be realistic with the rules

[Bpaccaud]

This is a 1973 240Z that was flood in 2003 (with 4 meters of water under the top)

The car was to a friend Eric (Tomzawyer on our Datsun Forum)

www.datsun-france.com

and i suggest him to built a race car for us, as the car was in poor condtition after flooding;

i done the works with my student, we start the project in october 2006; know the car was sand, and bodyshell parts were rebuilt, we build a rotissery for help the work

engine was take down, gear box too

a 6 points roll cage was bought and in september we put it on car

the engine will have (for starting), some little modifications, a good head, balancing, cams, but we keep the SU...

we have the better Original European FSC71A gear box with 3,90 final drive

For the wheel question... my technical friend tell me that we just must respect the maxi/ mini ; wheel + tire diameter for the period as specified in annexe K

[Bpaccaud]

exemple of works we done

[Bpaccaud]

hope it works this time:stupid:

[Bpaccaud]

dammed...

i will try tommorrow