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Hey guys,

If it isn't too much trouble, I wanted to tap into the vast knowledge pool of SAUWA to assist me through a bit of a predicament I find myself in at present. I have for a couple of years now been tossing up whether or not to do an RB 30 build (or equivalent 2.8, 3.0 or 3.2 options and so on), and now I have committed to completing my engine build (for the record, my head is already worked, cammed, ported & polished ect). I'm at a point I'd like to complete the build and get it out of the way, but obviously I'd like to do it once and do properly (If that means the difference between a half-arsed 20k build or a proper 30k so be it).

The crux of my problem is that I would also like to involve myself in some competition in the near future, I was aiming for Targa but have since been talked out of it (not in a peer pressure sense, but weight up the economics and the technical aspects and it isn't at all worth my while), so I'm looking for alternatives. My build is likely to feature a nitto stroker kit (3.0 or even 3.2), hopefully a solid turbo (my tuner has recommended a single garret turbo and my engine builder a TT set up he's taken from an RB26 with reconditioned snails), I'll have to upgrade injectors and while I was at it I was thinking of going to a front facing plenum (mainly to reduce piping and simplifying the layout in the engine bay), as well as going to a 6Boost manifold (I may as well while I'm at it...).

HOWEVER,

I find that targa and even improved production don't allow displacement increases.

ie:

4.5 Supercharging: Supercharging is permitted under the following conditions

(i) If a supercharger/s is recognised as standard production for the model, and all the following conditions are

met, the restricting orifice referred to in 4.5(ii) need not be fitted.

• All components associated with the induction system must remain operable, in situ, and unmodified.

• There are no additional components associated with the induction system fitted.

• Maximum inlet pressure and engine static compression ratio must remain in accordance with the

manufacturer’s specifications for the vehicle.

• The engines swept volume is not varied from standard by more than 2%.

• A boost monitor, as specified by CAMS, is fitted.

(ii) Where a supercharging system is not recognised for a vehicle, or where a vehicle recognised with a

supercharging system does not comply with 4.5(i), a restricting orifice must be fitted to the inlet tract/s prior

to the air entering the supercharging device/s so that all air used in the combustion process of the engine

must pass through the orifice/s. For vehicles utilising a turbine type compressor, the restrictor must be fitted

as per diagram 254.4 (see “Rally/Road”in the CAMS Manual of Motor Sport), save that the maximum internal

diameter of the air intake into the compressor is 36.0mm where a single supercharging device is fitted,S p e c i f i c a t i o n s o f A u t o m o b i l e s – G r o u p 3 J L a s t u p d a t e d : 0 1 / 0 1 / 2 0 1 2 6

© Confederation of Australian Motor Sport Ltd. All use subject to Conditions of Use at www.camsmanual.com.au

or 27.0mm where two devices are fitted. For other types of superchargers, the upstream extremity of the

restriction must be situated a maximum of 50mm from the upstream extremity of the moving compressing

media and be maintained for a distance of at least 3mm downstream. The maximum diameter of the

restricting orifice/s must be complied with at all temperatures.

Multiple supercharger installations are only permitted when fitted as standard to the model concernedwhereupon the original number and type of supercharging device shall be retained

Which in essence suggests that swept volume cannot be increased from stock (hence no stroking), and also, I understand that induction remaining unmodified means no alterations to intake manifold or turbocharger (or TT set-up).

Also,

Exhaust: The complete exhaust system is free downstream of the exhaust port (save for turbosupercharged

vehicles complying with 4.5(i) where the exhaust is free from the exit of the turbocharger) provided it complies

with Schedule B (refer "General Requirements for Cars and Drivers"). The original exhaust mounting brackets

may be removed and additional brackets may be fitted, provided that their sole function is the location of the

exhaust.

Which I guess rules out exhaust manifold too.. :/

I'm a bit at sea with all this, and I do need to make up my mind soon about what direction I take and how I go about the build. Also, if I may say so now, I have already spent the best part of 4k on suspension (Bilstein coil-overs all round, camber arms & traction rods), and I've also got some R34 Brembos lined up as well as increased cooling capacity. I'm not here for a dyno queen or a one-hit-wonder, I'm prepared to do it properly. I guess what I'm asking as well, is given the nature of my build, what categories would there be available to me if I were to proceed with the set-up I've described??

Thanks guys, I'll appreciate any useful or constructive feedback! :)

Edited by Marco-R34GTT

a question to weigh up is:

would you mind lag for fair amount of power up top (the trick then would be to keep the engine on song)

or would you want a responsive, less powerful twin turbo setup

cousin of mine has a 32r - 380/390HP

its got 34r snails on it, and with a full exhaust it boosts by 2500 rpm and full boost at 3500 (16-16.5 psi)

it pulls really really hard, but power now is limited by the turbos

personally...if you want a track car - something responsive with a decent whack of power would be good fun to play with

I've always liked the idea of having a responsive engine. Would happily sacrifice big numbers for an engine with a meaty power-curve and responsive free-revving characteristics.

In terms of engine power I've always been more concerned as to the way an engine makes power rather than just peak power.

The engine builder suggesting going the way of twin turbos, and I am open to the suggestion. However there are two things for me to consider. Firstly, it is double the cost, and two, rather than one component that could possibly fail; and secondly, how it would work in consideration with abiding by regulations of certain categories of racing and so on.

Cheers for the reply mate, I appreciate it.

As I said I do have to make this decision rather soon and the more advice I can get my hands on the better.

First thing you need to decide is WHAT you want to do with the car. Targa Tas, west point, targa west all run different rules (from what i understand) so while it may be ok for one comp it wont be for the next.

So do you want to:

-Rally (Taga, duton etc)

-club events (hill climbs etc)

-fun with mates

All of these and many other events you can choose from will dictate what you do to the car. No good building a $30k motor only to find out that you cant race it.

Check out the motor sport section they have different thread for some races.

The other thing to consider is WHERE you want to race. Targa is good and all but you have to transport to tas not only the race car but your crew parts and FUEL! apparently very hard to find a reliable 98 pump fuel in most of the small towns you go through.

If it were me i'd be looking at club events here in WA. Hill climbs, track days and maybe targa west etc. Check out the member secion there is more info on local races here.

So i say decide what and where then build accordingly and this will save money and tears in the long run.

Personally I would put a fresh RB26 with 2860-9's in your car, and sell your existing motor or head.

-Response(you are already talking about twins)

-Future support for more power

-WIll be a near standard setup, so good if you don't want police issues(do you plan on going to interstate tracks?)

-Most shops know how to build a solid RB26, and the aftermarket world is full of parts.

You COULD build a 2.8 RB26 with 2860-5's, but traction could be an issue... What is your budget for wheels/tyres/brakes/suspension?

Check the class regs of which every class you want to race in before you build.

Another consideration is if you go the targa route it's not a car that will be driven on the road. Also if you haven't done any events ( not sure if you have) I'd say you are a long way off doing targa. Just build 28,30 or 32 stroker with a single, there will be plenty of response and top end with gt35 or similar and then there is heaps or local events and series to race in ( not a once a year targa west or tassy ) and there are no restrictions on displacement etc

First thing you need to decide is WHAT you want to do with the car. Targa Tas, west point, targa west all run different rules (from what i understand) so while it may be ok for one comp it wont be for the next.

So do you want to:

-Rally (Taga, duton etc)

-club events (hill climbs etc)

-fun with mates

All of these and many other events you can choose from will dictate what you do to the car. No good building a $30k motor only to find out that you cant race it.

Check out the motor sport section they have different thread for some races.

The other thing to consider is WHERE you want to race. Targa is good and all but you have to transport to tas not only the race car but your crew parts and FUEL! apparently very hard to find a reliable 98 pump fuel in most of the small towns you go through.

If it were me i'd be looking at club events here in WA. Hill climbs, track days and maybe targa west etc. Check out the member secion there is more info on local races here.

So i say decide what and where then build accordingly and this will save money and tears in the long run.

Well I don't really know what I want to do with it, or more to the point, how certain regulation may affect what I could possibly compete in or not. My lack of familiarity with regulations is making my ability to decide one way or another more difficult that I would like. However for the record, I wouldn't be racing outside of WA for at minimum 2 years, maybe longer.

I would like to start at a fun with mates/club event car, with having the ability to evolve it into something more serious as my driver skills improve and ability to fund the project grows in time.

Hence why I'm asking the question, I'm really not wanting to balls this up, hence me consulting the higher gods so-to-speak! :P

Personally I would put a fresh RB26 with 2860-9's in your car, and sell your existing motor or head.

-Response(you are already talking about twins)

-Future support for more power

-WIll be a near standard setup, so good if you don't want police issues(do you plan on going to interstate tracks?)

-Most shops know how to build a solid RB26, and the aftermarket world is full of parts.

You COULD build a 2.8 RB26 with 2860-5's, but traction could be an issue... What is your budget for wheels/tyres/brakes/suspension?

Check the class regs of which every class you want to race in before you build.

Whilst I appreciate the advice, this isn't really a plausible solution. My engine builder has already sourced an RB30 block, my head has already had good money spent on it, and in that case I am already a little limited in what avenues I can take.

Another consideration is if you go the targa route it's not a car that will be driven on the road. Also if you haven't done any events ( not sure if you have) I'd say you are a long way off doing targa. Just build 28,30 or 32 stroker with a single, there will be plenty of response and top end with gt35 or similar and then there is heaps or local events and series to race in ( not a once a year targa west or tassy ) and there are no restrictions on displacement etc

Exactly, I need my car to remain partially useful as a daily for at least 18 months, and yes, while I do feel I am a decent driver. I have yet to cut my teeth proper on a race track or a timed event (RAC/AHG aside), I do feel that I do have inadequate skills to step up to something like targa right away. I reckon the 30/32 with a single would be awesomely responsive, particularly if I do pick a suitable turbo to match it. Cheers for the advice guys :)

Edited by Marco-R34GTT

Exactly, I need my car to remain partially useful as a daily for at least 18 months, and yes, while I do feel I am a decent driver. I have yet to cut my teeth proper on a race track or a timed event (RAC/AHG aside), I do feel that I do have inadequate skills to step up to something like targa right away.

I suggest that you try the Speed Event Series 1st, sprints and hill climbs. Then you have street cars at wanners. Targa may be a different game altogether but a big call!

I would also try some tuning days first as the track on your own is very different to being in a crowd.

Having HP is good but too much at the track can work against you. By sound of your suspension and brakes you may be only able to support 400 to 450 rwhp for sprints. Racing is another thing again in cooling etc.

Currently I only run 330 rwhp and pb at wanners is a mid 67s. It is responsive as and is deceptively quiet on the track. I am currently focusing on cooling and braking before I build a 25/30 with hp and response.

Is your motor dead or still going?

If its running- get out there and drive the car, build it once you hit its limits!

If the motor is dead, get a cheap short motor, and refer above statement.

Is your motor dead or still going?

If its running- get out there and drive the car, build it once you hit its limits!

If the motor is dead, get a cheap short motor, and refer above statement.

This

  • 3 weeks later...

Mark, Another way to 'get into it' for Targa is to look at doing some Navigation. That way you can simultaneously build your more 'open class' machine now, drive it on the road, and as others have said - do hillclimbs, barbagallo, collie, the RAC Sprint Rounds (starting in late March) and so on.

That way you get to have a blast now, have fun with mates and importantly get some track time. You will be amazed how much you learn - and that is not to say you are not a good driver now - you may have talent - but the track time will teach you more than you think.

And while you're doing all that - sit in the passenger seat of a Targa car. You'll learn even more there. Its obviously much cheaper this way - but you'll still spend >$2k getting suit, helmet with intercom and all the other bits that go with it.

I've done 3x Targa West, Wrest Point, High Country and Targa Tas. It is no exaggeration to say it is far beyond any of the events mentioned above and takes a lot of planning and car development. (and a bit of guts to sit there doing 200km/hr through bends amongst trees on damp road) Its awesome and I really encourage you to aim for it, but do a couple of years of varied motorsport first. (yes Dad...) :)

And make sure its varied, don't just do Barbagallo for example, you need lots of different roads, speeds and corners.

When you do come to do Targa in a couple of years, you'll want a purpose built car for the job - so I reckon go mad on this one and have fun in the meantime.

If I can help with anything there let me know, I can put you in touch with Targa organisers who could possibly hook you up as a Nav.

Is your motor dead or still going?

If its running- get out there and drive the car, build it once you hit its limits!

If the motor is dead, get a cheap short motor, and refer above statement.

Not this... Pm me on where you are at on the build, what parts you already have, your power goals, engine builder and tuner, how much money you want to spend...

I can help you out and give you some advice...

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