Improved Production Racing

[niss720]

I'm currently in the process of securing another chassis to build and race in an improved production class, How many people on here race their cars in this class? Have you run into any problems or limitations with these cars?

The biggest limitation I've found so far is that it is built in 1983, therefore its classed as an early model car and therefore is restricted in some ways including running narrower wheels and similar. Also I will not be able to convert it to Steering rack as it was never produced with them.

Does anyone have any suggestions, tips or advice?
Also what do you think i should include on the car as I will be completely stripping it and will have the opportunity to add some essentials. The obvious ones are battery Isolator, Strip all unnecessary weight, roll cage, tow hooks ect.
It is running a VR4 narrow block motor and a Wolf 3d ECU

Thanks Max

[RiceThief]

Having a quick look at the rules, you could convert your steering to a manual box and be able to run 8 inch wide rims, which isn't too bad. I read it as your minimum weight will be 1335kg based on the fact you are using a twin cam head.

I would convert the car to 5 stud hubs to open your wheel and brake selection, also run widebody front arms to increase your track as well. Look at the possibility of using a w58 gearbox with a dellow bellhousing.

Lummy races in IPRA and could give you more info.

[ACE]

I've run in the class before with a 2.6lt powered LA lancer. Good class, strong racing! Still have a number of mates running in the class, all be it in rotary's

The biggest thing you need to bear in mind is that you will need to run a 36mm restrictor on the front of the turbo to run the class and have a minimum weight you need to comply with if you run late model class

Have a look at there forum and get hold of the class eligibility officier or "EO" and he will be able to point you in the right direction. As the starion crosses the early/late model change over date, see you can run it as a late model car it will open up the bigger wheel, tyre brake combo for you.

I have toyed with the idea of building a "late model" starion to run in the late model class.

My thoughts........ Late JB or JD
17x9's with 255/45's
340mm disc's, porsche/ap/brembo calipers & pedal box
2.6 turbo, E85, motec ecu & dash
RX7 dogbox
MCA gold suspension
Minimum weight 1315kg

Should make close to 350rwhp at 6500rpm (limit of the restrictor)
And looking at how quick the S13/14/15 chassis's are with restricted SR20 turbo's, it should be a real bullet!

[Lummy]

There's not enough advantages to running LM over EM in my opinion. I would stick with EM and therefore and have no minimum weight. 8 inch rims is plenty - lap records have been set on 7 inch rims.

I've raced IP on/off in NSW and VIC. It is a great racing category - VERY competitive and ends up costing a lot of money if you want to be half competitive. But it is a hell of a lot of fun too.

I run a 4G63, stroked to 2.3 litre. The 36mm restrictor means all the fun is over by about 6500rpm, but there's plenty of torque and I still manage to get well over 300rw HP which is enough for a lot of fun.

You should buy mine instead of building one - it'll cost a fraction of what a fresh build would.

[ACE]

So your saying the extra 60mm of rubber front & rear, the extra 50mm in diameter of front brake disc, the big rear wing you can run, as a start, is not worth building a late model starion?

What does the Sapparo weight? Its got to be close to 1250kg with a driver and a full tank of fuel? The Group A cars were under 1300kg with a 120lt fuel tank on board. On the basis that my LA 2 door weighted in at 960kg (2.6lt, 13" wheels, scorpion diff, etc....) with me in it and was doing 1.50's and the other one that was running at the time was doing 1.47's at the creek in the late 90's.

My thoughts are you would have to add ballast to a Starion to make the minimum weight which has its advantages and watching the rotaries trying to keep up with the commodores and Wattys new S15 the other weekend was quite entertaining.

Go back and have a look at the times from the mid to late 90's. Generally the cars are not any faster than they were back then. Most of the rotaries are still running in the 46's (at the creek) back then and they are still doing that now with a corner removed!

Each to there own, but I think a the late model class will eventually rule the roast over the older cars.

[redzone]

Craig's group A starion weighs 1100kg fyi.

I'd recommend running old school with 17x8's & no minimum weight.

[Lummy]

Can't go more than 15 inch for early model. 15x8 would be the biggest you can go.

My car weighs in at just under 1200kgs race weight.

[redzone]

Hmm that sux..

[callan_rs2000]

My car is logbooked as IPRA but I run in a new class in Tassie called Muscle Car Cup which caters for any logbooked car pre 1983 and Group A/C replicas.

I have widebody front control arms to get more negative camber at the front which is a must.

I have also kept the 4 stud hubs. My front brakes are S13 SR20 Silvia front brake discs with Wilwood 4 pot calipers which only need a minor bracket made up to bolt to the Starion struts. Any good fabricator would make this for next to nothing.

With the new roll cage rules your car may end up weighing close to minimum weight. Maybe get a CAMS approved cage put in first and see how it weighs. If its close to 1300kg you could go LM, if its closer to 1100kg go EM??

The biggest problem I had was lowering the car. I wanted to lower my Starion a reasonable amount but would have lost all travel in the shocks, apparently Bilstein can do a reversed shock but its costs a shitload.

[redzone]

Shorten the strut bodies to retain the travel, or run d2's with better spring rates!