MSNZ - Schedule K and T&C and maybe FIA HTP related questions info etc

I thought I would start this thread given some posts on other threads about Schedule K, T & C and even FIA HTP.

I am looking at this thread from a pure Saloon, Sport and GT point of view as most of the open wheelers, F5000, FJ etc will already be well aware of the process of Schedule K or FIA HTP.

First we don't seem to have many Saloon, Sport and GT cars that are to Schedule K or FIA HTP standard. Most cars seem to be running under T & C - please correct me if I am wrong.

I would like the aim of this thread to answer a few questions and maybe help others (including myself) prep our cars to one of the standards that best suits how we want to race, our budgets, or how we want to even build our cars.

I have taken a few quotes/posts from another thread

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Originally Posted by nzeder

I have not spoken to the members from the "Datsun Z Club" that attended the AGM yet - but I am interested to know more about how T&C and Schedule K is seen. My Datsun Z that I am trying to get ready for the coming season (when time and money permits - both of which I am short like so many) is currently nothing more than a rolling caged shell stilling at my parents (don't have room here with another Z in bit in the shed). I have not committed to the brake setup and my suspension has not been setup completely either (coilover only held in place with hose clamps waiting for final ride height etc). All the mods are true to the factory options or period mods. So now with the comments above about T&C should be abandoned/made redundant - what should I do?

I still need to run new brake hard lines and fuel hard lines (inside the car away from the factory location right next to the drive shaft - so a safety mod which should be permitted just on safety grounds along). My car is all factory panels, missing the odd badge (but I have some from the road car that I can install).

So my question is this to those who attended - can I get my car finished and through as a Schedule K "competition sport & gt car" aka group o? The car will be missing some interior that can't be refitted around the cage - a Datsun Z is not that large inside. I do plan to run period brakes and rims that are period replicas (who want to be running on 1970's magnesium rims - 1 they cost a packet, 2. they would be old magnesium rims so that is just dangerous) All the mods I can proof are period mods and I am replicating them as they were. This car I am building will be road legal once I complete it when the $$ are their to go though all the hoops you need to get car with a full cage on the road.

However with the comments about T&C and the like do I just give up now and just focus on getting my road version going and spend time with my young family and forget my hobby of classic racing?

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Originally Posted by Howard Wood

In my experience the schedule K requirements are less onerous than getting a roll cage homologated. My BMW "02 which has a sched K classification is a replica, not an original race car. I don't understand various people who persist in thinking it is a requirement.

You simply need to list the modifications together with the justification which can be, in descending order of importance, homologation papers, period books, photos and magazine articles or lastly current photos or articles. In my case to complicate matters the original Group 2 papers are listed by the FIA "Lost, not available" but BMW Mobile Tradition in Munich were able to supply me from their archives sufficient (around 250) pages of amendments and additions together with enough of the original pages to piece together the major homologated items and make some assumptions about others. For example 4 pages of brake rotor and caliper sizes implies wheel diameter dimensions which were not included amongst the information.

MSNZ processed the application quickly and efficiently, a couple of questions about one or two specific items and the stamp went down! Obviously with a car where the complete papers are available, it will be even easier. Why there seems to be so much reluctance to embrace Sched K is beyond me. It fixes so many of the issues prevalent in "classic" racing.

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Originally Posted by Kiwiboss

nzeder, Schedule K is for exact "period" built race cars with the idea of obtaining a FIA Historic Technical Passport(HTP) and T&C is for "Modified" saloons and sports cars with only certain allowable changes, with the idea of obtaining a Certificate of Description(COD)!! This here is only a debate, nothing is changing within Motorsport NZ and the Classic and Historic commission from my understanding is more than happy with the current status-quo!! so you can either build your 240Z to NO rules and race it club type events were there is less concern about rules, or to K/T&C and be eligible for more pure Historic and Classic events like say the Festival!!

To be-able to race with HMC in future events like the "Legends" you will need one of the above as we won't except vehicles outside the K/T&C, HMC criterior.

And that's what is great about NZ motor-sport, you can choose your desired path.

Dale M

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Originally Posted by Kiwiboss

So i take it Howard that you have at MSNZ HTP?

Dale M

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Originally Posted by Howard Wood

I was originally planning to apply for an FIA HTP but was advised by MSNZ that it would take over 6 months and to apply for sched K and COD in the meantime. As the car was completed and I was itching to go racing, it seemed the best interim option.

The HTP would allow the car to compete (and presumable be saleable) anywhere in the world, however much as that would be a nice dream it is unlikely to happen! In any case, speaking recently to a NZ Formula Junior competitor who has been lucky enough to get an invite to Goodwood this year, the technical compliance regime for meetings such as that are very specific and detailed. I didn't ask, but I gathered, way more restrictive than the HTP.

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I have also contacted MSNZ about applying for FIA HTP and as informed this is great if you attend to run the overseas at a Historic & Classic International Meeting. I too was told the process can take sometime while things are checked and verified. If the car is only ever planned to be raced locally in NZ then the Schedule K and COD is the simplest solution.

I have spent the last few evening reading and re-reading not only the MSNZ Manual 35 on Schedule K and T&C but also the FIA Appendix K. I have been trying to take this all on board and understand it all. It can be complex at times especially if are also looking at the things you might want to do on a build as it can alter the cars period and therefore the rules that apply to the car as it will have to be classified.

This is the important bit that I can make out - the period of car will determine what can and can't be done to the car in question.

There is a lot of similarities between MSNZ Schedule K and FIA Appendix K however in reading all of these documents MSNZ Schedule K is a little bit easier to understand - assuming I have got it right - hence this thread so we are clear and we all understand the rules in which our cars are run under/audited to etc.

Some of my post might be a bit long so I apologize up front for that.

The key to all this is as I see it with the COD and FIA HTP is this it is a point in time freeze on the car in question - it means if the COD and/or FIA HTP is to be valid then the car can't be altered.

This might be the rub for why we don't have many K cars (let me call it that for short hand. K car/s where I use this implies either a MSNZ Schedule K or FIA Appendix K with HTP) as most have altered their cars as they keep racing them, get faster or budgets allow new bit and pieces.

I believe this is the whole point of the K car process - so keep control of budgets and lock in the car so modern technology and improvements are not morphed into a classic car - can I also add that I will drop the Historic in this thread as to me that implies an open wheeler and classic means a Saloon, Sport and GT cars - that is just my opinion and I happy to be persuaded into another way of thinking please send me a PM if I need to change my way and keep this thread on topic :D

Was thinking myself that a thread like this was necessary, so thanks for getting this underway.

So lets first clear up some of the confusion over K cars - they don't have to be "The Car" from the day they can be a new build finished today, tomorrow or sometime into the future. K cars can include "The Car" from the day but also these new builds.

The key point is the new builds and even "The Car" must be true to the Period the car is built to. This is my understanding having read the documents.

So for example if you managed to acquire a genuine....let me talk about the marque of car I own and love (sorry if you don't like them I do and I know a lot about them) 1970 Datsun 240z ex Works Rally car. Maybe the find/purchase was lucky and it was a freeze in time a true barn find so you only need to restore the car. Then the process is simple (costly sure) but the car is correct, parts are correct just need to do the paper work etc. Depending on the state of the Works car as I now Nissan changed the groups the cars were homologated for will depend on the group/period the car will be classified under either MSNZ Schedule K or FIA Appendix K HTP.

Again this is a dump as my brain that hurts from this reading to make sure I have got it right and other get the same results as I.

Again lets assume you find "the car" but it was modified sometime in 1974 for circuit racing. You know have a choice - restore the car to 74 period or remove the mods that are outside the rules for when it ran in 1970 and restore to that spec and apply for the paper work.

The same applies to a Datsun 240z you find/purchase on trademe/via a club member etc. You have choices when it comes to K cars.

1. Run it as a Group 3 (that what Datsun 240z/260z/280z aka S30 chassic) Standard Production Sport & GT car = the car must match those rules/FIA homologated for the period chosen basically a standard road car.

2. Run it as a Group 4 Competition Sports and GT - all the Works parts were mostly homologated under this group. ie a Works replica like "the car" described above - however you have to find or replicate the works parts so they will be accepted as true replicas of original parts - having said that "the car" might need to do the same if the parts are not there or unusable.

Depending on your chosen Marque and model of car you might have more scope for changes as that manufacture might have homologated more optional parts under different groups etc. However there are some bits in the rules that are very clear you can't mix and match from different groups and periods to build something that suits you ie the best of each bit.

An example of that is pre 72 fiber glass doors, bonnet, guards where permitted for a given group and pre 72 is the period. Now if you want to run 4 pot brakes that were approved in 76 replacing the 2 pots then you have to give up the fiber glass panels as they were banded after 72. So you can't run both the fiber glass panels and the 4 pots in the period of the build. So you pick the period and stick with it.

This is where all the documents and evidence you can get the better chance you have of running the car - if you can't proof a part was used via the methods outlined in the documents then the standard part is applied.

If a car had a 4 link in 75 and only a SOHC but in the same make and model ran but in 70 ran a 2 link and DOHC you can't have the a 4 link and DOHC and run either period.

K cars are to be build and ran as Homologated first and for most then as I read the MSNZ Schedule K then other options from the period can be fitted if the car is classified correctly ie adding an part from the options/sports list might mean the car is not longer a "Series Production (Saloon) car" but becomes in fact a "Competition Touring Car"

I will talk about Schedule T&C next.

Keep it going Mike. I believe you are spot on so far and although Nigel Russell's example at conference was originally a single-seater, what he emphasised was exactly what you have stated. You must be true to the year and then supply supporting documentation for Schedule K.

I'll sit back until after you have covered the T & C side as that is probably where there is a really good debate!

nzeder,
Your read of the document is exactly as I understood it too. Specific examples probably better illustrate the process for obtaining a Sched K classification and your example of a Datsun 240Z is a good one.For that reason I will briefly explain the background to some date and specification decisions I needed to make over the '02 build and subsequent application.

From about 1972 to 1975 BMW and Ford were engaged in a furious battle involving homologating all sorts of "optional extras" for the 2002, CSL, Escort and Capri in an effort to win both the overall European Touring Car Championship and the 2 litre class. In theory to become homologated 1000 examples had to be produced. The game changer was the arrival of Ford's BDA engine so for 1974 the FIA changed the rules to allow 4 valve heads if 100 examples were built together with virtually unlimited bodywork modifications. The 1974 BMW works 2002s had the 295 hp M12/7 Formula 2 engine, rear mounted radiators, wings and 14inch wide rear tyres! Not an easy car to replicate even if you have a spare 50,000 Euros to buy an M12/7 engine. Plus they are butt ugly!

My research suggested that the last of the 2 valve M10 engined Group 2 cars from 1973 had the best combination of homologated components and by a happy co-incidence the factory build date of my car was late 1973. At this point I started trolling through the 250 odd pages of (in German) Homologation pages and supplements kindly given by BMW Mobile Tradition and compiled a build sheet long before putting a spanner near the car.

This process obviously is easier with a "new" build. Almost any car with competition history, unless abandoned in a barn will have been modified, often dramatically, in order to keep it competitive or because the expensive pukka bits broke and were too expensive to repair.

Hi nzeder, I’m fairly new to all this Schedule K, T & C, HTP , COD and so question the relevance of this revenue generating bureaucratic bull…. so thanks for starting this thread, I’m sure we can all learn from others experience with these matters. I can see the necessity for historic , period correct cars that wish to race internationally , but for the rest of us that just want to get out there and have some fun then, why should we bother getting involved ? If ERC can run his series for so long with consistently large grids , then perhaps we all need to adopt to KISS principle to our racing.

Would someone who has the patience to read and try and understand the rule book sort out what of the following is allowed and where this car would fit into the various classes and schedules.
The car is Italian 1971 with 1600cc dohc engine, 5 speed transmission 4 wheel solid disc brakes as standard equipement.
The normal modifications for "say" Targa/club type events would be:-
2000cc dohc motor (modified but not dramatically) 2 x 40/45 DCOE replacing the original 2 choke down draft, different camshaft profile, ignition from same manufacturer 1975 on etc
5 speed transmission from 1975-83 same manufacturer but different model
The differential is Japanese
The front rotors are larger and vented (late 1980s) the rears solid although larger.
The calipers are 1990s from the same manufacturer
Caged with MSNZ approved seats and harnesses etc
So apart from the Japanese differential the entire mechanicals of the car is from the same manufacturer although not necessarily the same model. The reasons, like those of most car builders, for the mods are to make it go, make it stop, make it safe and make it reliable.
Any thoughts?
Allan

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Originally Posted by Allan

Would someone who has the patience to read and try and understand the rule book sort out what of the following is allowed and where this car would fit into the various classes and schedules.
The car is Italian 1971 with 1600cc dohc engine, 5 speed transmission 4 wheel solid disc brakes as standard equipement.
The normal modifications for "say" Targa/club type events would be:-
2000cc dohc motor (modified but not dramatically) 2 x 40/45 DCOE replacing the original 2 choke down draft, different camshaft profile, ignition from same manufacturer 1975 on etc
5 speed transmission from 1975-83 same manufacturer but different model
The differential is Japanese
The front rotors are larger and vented (late 1980s) the rears solid although larger.
The calipers are 1990s from the same manufacturer
Caged with MSNZ approved seats and harnesses etc
So apart from the Japanese differential the entire mechanicals of the car is from the same manufacturer although not necessarily the same model. The reasons, like those of most car builders, for the mods are to make it go, make it stop, make it safe and make it reliable.
Any thoughts?
Allan

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Have a look at Schedule RH, it may suit your purpose better

Thanks Carlo.

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Originally Posted by Allan

The normal modifications for "say" Targa/club type events would be:-
2000cc dohc motor (modified but not dramatically) 2 x 40/45 DCOE replacing the original 2 choke down draft, different camshaft profile, ignition from same manufacturer 1975 on etc 5 speed transmission from 1975-83 same manufacturer but different model
The differential is Japanese
The front rotors are larger and vented (late 1980s) the rears solid although larger.
The calipers are 1990s from the same manufacturer
Any thoughts?
Allan

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My thoughts are that it is perfectly OK in the ERC Series - without any documentation...

Thank you also ERC. That's more like what I wanted to hear. It wouldn't fit into schedule RH as I read it.
Like many people thinking about building some sort of competition car I really need to know what is acceptable to the various series that exist in NZ so as not to turn up only to be turned away because I didn't do my homework first.
Allan

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Originally Posted by Allan

Thank you also ERC. That's more like what I wanted to hear. It wouldn't fit into schedule RH as I read it.
Like many people thinking about building some sort of competition car I really need to know what is acceptable to the various series that exist in NZ so as not to turn up only to be turned away because I didn't do my homework first.
Allan

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I think you have answered your own question in the last phrase!
Targa (having been on 10) will allow almost anything, you just need to declare and you will be classed. Be prepared that a number of classic competitors are getting tetchy about the "hot rods" which are a mish mash of bits and would like most "classic" to revert to period components, with the appropriate wheels, tyres, brakes, gearboxes etc. Seats, roll cages are a different issue. In regard series, you need to check where you want to run, conform and if you don't want to conform, accept that they may not want you. It's your choice.

Allan, you may also want to check out Alfa Trofeo. Oldfart is correct, some do get a bit tetchy but I believe Alfa can offer an invitation to any Italian car if they so desire. The reason for that is straightforward. Unlike BMW, there are not vast numbers around at a fair price so viability as a race series is dependant on numbers. Like us, Alfa have a few issues with T & C but we work very closely with them as there is a certain synergy that outsiders (and critics) probably do not fully understand, but it may well come out in this thread - eventually.

Quote:

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Originally Posted by Allan

Would someone who has the patience to read and try and understand the rule book sort out what of the following is allowed and where this car would fit into the various classes and schedules.
The car is Italian 1971 with 1600cc dohc engine, 5 speed transmission 4 wheel solid disc brakes as standard equipement.
The normal modifications for "say" Targa/club type events would be:-
2000cc dohc motor (modified but not dramatically) 2 x 40/45 DCOE replacing the original 2 choke down draft, different camshaft profile, ignition from same manufacturer 1975 on etc
5 speed transmission from 1975-83 same manufacturer but different model
The differential is Japanese
The front rotors are larger and vented (late 1980s) the rears solid although larger.
The calipers are 1990s from the same manufacturer
Caged with MSNZ approved seats and harnesses etc
So apart from the Japanese differential the entire mechanicals of the car is from the same manufacturer although not necessarily the same model. The reasons, like those of most car builders, for the mods are to make it go, make it stop, make it safe and make it reliable.
Any thoughts?
Allan

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With out knowing the model and no research I could not comment on FIA HTP or Schedule K as both are based on the same principle and for FIA HTP that is what was homologated in the period the car fits into. Schedule K is same. Things become tricky when there are not FIA homologation papers to build to.

This is where I think we are lucky here in NZ we have Schedule T&C - which I will now see if I get this right.

T&C rules are basically a really good platform for most classic racers - it has some flexibility but then is tight on other areas.

The principle is take a standard series production car be it a Saloon or Sports/GT leave the body work 100% standard leaving all bumbers, bright work etc - but then allow modifications to the selected model based on the rules set in the out in T&C. Over the years however there has been a lot of mis-interpretation of the rules. MSNZ has during this time re-written/worded the rules to make it clearer as to what the principles are. However I believe there is still a lot of confusion with regards to T&C. Let me see if I can get this right.

First an opinion - I feel that some areas in any form of motorsport car preparation should be not negotiable. I believe that replacing standard rubber brake hoses with a braided hose should be compulsory just on the grounds of safety - much like your comment about make it stop Allan.

T&C is I feel very clear also - Pick your car example a Ford Mark I Escort. The model you might purchase is a 1300 but you might feel that you would to race a RS2000 - so under T&C you can do this as it is in the same model series. Again as the cars in question are mass produced ie more than 1000 examples manufactured over a 12 month period - if the model you select does not meet this then you need to turn to FIA Appemdix K HTP or Schedule K COD and see if the model can fit under a period replica/fresh build to the FIA homologation of the model in question = lots or research to get the proof such a car did run in the configuration you require as that is outside of T&C which must be based on a standard production car - so something like a Hobay Escort does not fit T&C as that car was not sold to the general public - it is a FIA special, a period race car so needs to be built to FIA homologation under FIA Appendix K HTP or Schedule K COD.

I have not read the rules on Schedule RH or CR or others - I so far have only researched K and T&C.

So under T&C your now selected RS2000 Mk1 (made from a 1300 2 door) needs to have all the original body work as fitted and sold on the RS2000 - so if that means GT front steel guards then you should be sourcing some of those if the RS2000 only came with those (I don't know escorts so if I am wrong please correct me - again I am Nissan S30 aka Datsun 240z/260z/280z Fairlady Z, Fairlady 240Z, Fairlady 240ZG, Fairlady Z432 and the Fairlady Z432-R all the same chassic different markets/models/specs and some different options/configurations). You can now modify the RS2000 as permitted in the rules - 15" max under T&C, no front spoilers, only factory rear spoilers (so no homologated special parts, bubble flares etc these are non standard body parts - not fitted or sold to the standard production cars). Engine can be enlarged, cams changes, etc - all this is very clear in the rules. Suspension and brakes can be modified/changed as stated in the rules. However the key is these changes my have been available and carried out on a RS2000 somewhere racing in the world and be proven these suspension/brake mods were carried out.

I think if they can't be proven but you know it could have been done then I think Schedule CR is what you can look at for a retrospective replica/special.

So that is how I read the T&C rules - it is not an anything goes, it is if it was done it can still be done.

I don't think using a modern rotor is an issue - for example take my car a Datsun Z - if I build to K car spec the FIA approved brake setup can't be replicated today with new parts as they are NLA (no longer available), rotors can't be purchased, second hand calipers can be purchased and seal kits for them are still available. So I assume the FIA and others like MSNZ would allow a suitable replacement if dimensionally correct. ie say a car was homologated with a 276x20mm rotor but that is NLA but you could modify a BMW E36 rear rotor to fit which is 276x19mm then that should be acceptable and this is even covered in the FIA Appendix K rules - parts can be replicated if the material/process of manufacturing and dimensions are the same.

I am sure if budget was no issue you could have a foundry make new rotors to the correct dimensions etc...however I am sure most would be fine with a suitable substitute.

So that is how I read the T&C rules - must be based on standard production model range using the standard body - much like Schedule K and FIA Appendix K for Series Production (Saloons) and Standard Production Sport & GT. However you are not limited to the FIA Homologation for these standard base models - ie if only homologated with downdraft carbs then that is how it is to stay in a K car config - however T&C allow the fitment of DCOE if this was done in period aka if that was done to a Competition Touring Car - without having to conform 100% to the FIA homologation for the model as a Competation Touring Car - so it is more like a 1/2 way point - a little more scope than a FIA Group 1 or Group 3 homologated car but does not have to be as 100% like the Group 2 or 4 etc.

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Originally Posted by Parnelli

Hi nzeder, I’m fairly new to all this Schedule K, T & C, HTP , COD and so question the relevance of this revenue generating bureaucratic bull…. so thanks for starting this thread, I’m sure we can all learn from others experience with these matters. I can see the necessity for historic , period correct cars that wish to race internationally , but for the rest of us that just want to get out there and have some fun then, why should we bother getting involved ? If ERC can run his series for so long with consistently large grids , then perhaps we all need to adopt to KISS principle to our racing.

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My only reply to that is reading the rule book if any event is run/held under MSNZ Appendix 6 then cars running need to have a COD ie be classified as Schedule K, T&C, CR etc. If a meeting he held under Appendix A then it is a clubman type event and then anything goes it is clubmans racing as I once heard from a HRC member. However girds sometime also have a set of rules to run under - ie BMW etc to have good safe grids without large speed differential.

I like handicap racing - it is a leveller, fun and if all respect each cars and ability then everyone finishes after all we are talking about cars that finding parts/panels are becoming harder and harder and more costly. There is no reset like on a Playstation and all is damage is gone.

I do agree with the KISS approach - and if you look at T&C it is a very KISS set of rules - it is clear so I don't see how there are so many "hot rods" racing. The issue we see with T&C today is with existing cars - that have been modified outside of the rules as they are today ie not trying to pick on a bubble flared escorts but that is just not a standard production body - not matter what rule book you read - yes homologated under some FIA group but that does not mean it fits T&C

It would be like if I built a Datsun 240z to full Group 4 Spec with all the Group 4 body work - here is a picture then try and run that under T&C = epic fail it is not standard production body work. However the next picture is a standard Datsun 240z well in this case a Fairlady 240zg which was used to homologate the longer nose and flares in Group4 -so the top pic = not T&C but the bottom is as that is the standard production body work.
1975/76 Le Mann Datsun 260Z - period race car aka K car
http://zhome.com/History/LeMansZ/1975LeMans240Z.jpg
1972 Fairlady 240ZG - production car
http://carphotos.cardomain.com/ride_...0622_large.jpg

It is encouraging to see there are people that take the time to read the rules before they build a car rather than build one and try to get the rules changed to suit.
This will be a great thread for people to understand the K,T&C rules and where they apply, you can still build cars for series rules but if you want to build one to race in Classic or Historic racing read the rules first and save yourself and the commission a lot of problems later.

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Originally Posted by Allan

Would someone who has the patience to read and try and understand the rule book sort out what of the following is allowed and where this car would fit into the various classes and schedules.
The car is Italian 1971 with 1600cc dohc engine, 5 speed transmission 4 wheel solid disc brakes as standard equipement.
The normal modifications for "say" Targa/club type events would be:-
2000cc dohc motor (modified but not dramatically) 2 x 40/45 DCOE replacing the original 2 choke down draft, different camshaft profile, ignition from same manufacturer 1975 on etc
5 speed transmission from 1975-83 same manufacturer but different model
The differential is Japanese
The front rotors are larger and vented (late 1980s) the rears solid although larger.
The calipers are 1990s from the same manufacturer
Caged with MSNZ approved seats and harnesses etc
So apart from the Japanese differential the entire mechanicals of the car is from the same manufacturer although not necessarily the same model. The reasons, like those of most car builders, for the mods are to make it go, make it stop, make it safe and make it reliable.
Any thoughts?
Allan

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Hi Allan. It's good to get an actual case study. I presume your car is a FIAT? All the mods are acceptable under T&C except perhaps the engine size? Did your model of car have an 1800 cc derivative, because the maximum increase in size allowed is 12 1/2% for T&C?

If the car a Fiat (which it sounds like given the specs given - a model that went from 67-75 if I recall - like them too ;) ) the it will have the Lampredi's Twin Cam engine which was available in 1297cc all the way to 1995cc. As RacerT points out T&C allows 12.5% cc increase over the base engine. So if the model is the same much like a Datsun 240z is to a Datsun 260z and the US market Datsun 280z in 2 seater form share most of the same suspension, chassic, external body work with only minor upgrades like engine, different dash and other things but the base chassis is still an S30.

So lets say that is a Fiat 124 coupe then they are a continuation in the model AC -> BC -> CC based on I assume the C platform - much like the Datsun Z ie S30 = 2l JDM, HS30 = 2.4 240z, RS30 = 2.6 260z and HS30 again = 2.8 280z. So the CC had the 1756cc engine. So 1756 + 12.5% = 1975.5cc which is still a bit low for the 2l version which is 1995cc. So in this case the engine would be outside of the T&C rules.

The ones that get me are when someone creates a Hot Rod and claims classic. I hope I don't upset anyone as the following were built to the Targa framework, but a fairly good number of long term Targa competitors have left as a result of the following and similar.
Datsun Z with forced induction Chev, still claiming original year, Charger with Jericho gearbox, still claiming original year, Torana Hatch with LS, same claims.These are not the only ones, and as said above were built within the guidelines, but the essence of "Classic" is lost, and the outcome has been that the true classics go away.
Against these, and at the time are Avenger (factory race history) in original form, Renault A110, still running as built, solid discs, factory box, engine prepared as works, etc etc.
Rant over :)