Impreza World Rallying Scene

Subaru entered the world rallying scene with the Legacy saloon in both group N (show room) and group A (modified) classes. Although it was relatively quite a large car they had a lot of success on both the national and international scene.

Group A Impreza

Copyright © Prodrive
Cut away view of an Impreza rally car - the car that started a cult!

In 1993 the Impreza made its debut in group A with a similarly powerful 2 litre engine and 4 wheel drive but packaged in a relatively small body, the car looked a winner. The Subaru Impreza was first seen on a competitive rally stage on the 1000 Lakes, two cars being driven by Ari Vatanen and Markku Alen. Mixed fortunes beset the car on its inaugural event when Alen flew off the road, ripped a wheel off, and slammed into a rock. Conversely Vatanen lead the rally early on, set some fastest times and came in overall second!

In 1994 a certain British driver Colin McRae and his co-driver Derek Ringer won the RAC rally in an Impreza and the car suddenly gained cult status being voted Rally Car of the Year by Autosport readers! They repeated the feat in 1995 to take the World Rally Championship for both drivers and manufacturers, and amazingly the rally finished with an Impreza 1-2-3!

Copyright © Subaru UK
Colin McRae and co-driver/navigator Derek Ringer, the 1995 World Rally Champions!

In 1996 McRae won three of the World Championship rounds but unfortunately lost the drivers title, but Subaru retained the 1996 manufacturers title. Again Autosport readers voted the car Rally Car of the year for the third succesive season....and waiting lists for road going cars grew.

Copyright © Prodrive
Colin McRae in winning style on the Catalunya Rally in Spain, November 1996

Although the group A class is not used today by Prodrive/Subaru in the WRC, the works team moved on in 1997, there are Imprezas entered into National and International events under these regulations. The late Bertie Fisher used to great success a group A Impreza in Irish tarmac events during 1999 and here it can be seen during pre rally preparation. Note the size of the disc brakes!


1997 - A new era

World Rally Car specification Impreza

1997 saw the launch of a new breed of rally cars, returning almost to the days of the Group B. The requirements to produce 2500 homologated specials was dropped, allowing manufacturers to use an existing model from the range, and develop it for competition. The WRC rules can be applied to any car which has sold more than 25,000, engines can be transplanted from another car in the range and a 2 wheel drive car can be extensively modified to 4.

The new regulations have relaxed the number of actual modified cars which must be sold to the general public, and have increased the modifications allowed over the standard vehicle it is based. Ultimate restriction on power output of around 300bhp come from a maximum permitted turbo inlet and the speed and cornering abilities are kept under check by a maximum width on tires.

Copyright © Prodrive
The 1997 Subaru World Rally Car contender

Subaru were the first manufacturer and team to take advantage of the new rules and the new car has been built to the new World Rally Car specifications entirely at Prodrive. This is a first for Subaru who normally supply the cars pre-built ready for preparation. Designed by Peter Stevens and engineered by Prodrives David Lapworth, the basis of the car is an Impreza Coupe (also known as the Impreza Retna) but it is heavily modified and is vastly different from the road going car.


Richard Burns Subaru Impreza WRC99 in preparation for the Acropolis Rally

The cars are built from a bare production shell in-house with over 400 man hours to bring it up to WRC specification. It is much wider than the standard car with steel panels, aluminium bonnet and fibre glass used for the bumpers and spoilers. The sculptured body work along with the huge wing give aerodynamic benefits in terms of down force thus gaining grip and cornering speed. Carbon fibre is used extensively inside making up the dashboard, door panels and any other item where a weight saving can be made.

For 1999 the the transmission is an electro-hydraulically controlled manual box. The technical name for the whole affair is ATM - Automated Manual Transmission. This differs from the competition who have moved to a sequential gear box, whilst Prodrive have opted to automate the stronger traditional H pattern box using electro-hydraulics. In the rally environment, reliability is paramount and losing a gear in a sequential box usually means a retirement, but on the Prodrive system the driver can revert back if required to the manual H shift. The drivers can't skip gears - the paddle only shifts up or down. But there is much less chance of damage to the box because the change is controlled electronically - it can sense when the gears are aligned so you don't get some hooligan chipping corners off the gears. The gear change can be seen on the interior picture above as the small lever on the steering wheel.

If the worst should happen and the car loses a gear, the box can be reprogrammed in service to skip that gear - impossible in a sequential box. But the chances of losing a gear in the first place is much smaller because of the better quality gear change... Suffice to say they've never had to do it in competition!

Also a big benefit is that the driver now has a big switch on the dashboard. Turn it left and the box automatically selects neutral. Turn it right and he's straight back in to first. No having to change right back down through the box after a sixth gear spin! The drivers have even been known to have the car back in first gear before they've actually stopped spinning - try that with a sequential box!

Extensive modifications to the engine are allowed, with larger turbo chargers, water injection and engine parts changed for much lighter items.

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The normal intercooler which sits on top of the engine is replaced by a massive intercooler located on the front grill. The airbox is replaced by an enormous carbon fibre item too.

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Seen here in preparation for the Acropolis Rally is Juha Kankkunens Impreza WRC99. Note the size of the front mounted intercooler! Also the traditional bonnet intercooler air scoop is now blanked off on the WRC99 cars.

Of course the go faster bits are suplemented by some very nice go slower bits, such as increased brake discs and huge calipers. The suspension is hand built for each event and far bigger and stranger than normal.

Prodrive no longer manufacture new Group A cars but as seen above, will prepare and run them if required as for Bertie Fisher. So what do you do if you want to really compete at the top level today?

If you have the money (reputed to be £250,000 for a season) you can buy a WRC! Alternatively how about a hire drive scheme, including tuition, mechanics, spares etc. Here are pictures of one such WRC98 as used in 1999 in the "Allstars" programme in preparation for the Acropolis Rally and to be driven to eventual 9th place. To do a full season under the Allstars banner would require nearer £2m (and you don't get to own the car!)

Note the interior of the car is slightly different to the WRC99, with a more normal gear change and slightly less carbon fibre.

The engine bay is slightly different to the latest cars but you still get the massive front mounted intercooler and carbon fibre air box etc.

WRC2001 - Prodrive 44S

The Impreza has under gone a number of changes through the years. The body had a face lift at the end of 1996 which co-incided wih the introduction of the WRC. Now at the end of 2000 the New Age Impreza has been introduced with a totally different body, running gear and engine and the World Rally Car Impreza follows suit.

copyright © Subaru World Rally Team

Although the car upon which it is based is all new, the WRC2001 utilises nearly 80% of the WRC2000. Of the old model, the body, electrics and interior are the only things not carried over.

The new road going Impreza is heavier than the older model but this extra weight comes from extra refinement in items such as air conditioning, in car entertainment, sound deadening material, trim etc. which get thrown out at the preparation stage anyway. In fact Prodrive claim the new 44S could be a few kilos lighter than the WRC2000 and the stiffer bodyshell introduced because of changing crash test requirements is a big advantage to the rally car.

The car has significantly better aerodynamics than the out going model which will help on the high speed tarmac rallies. The wider track and bigger wheel arches allows the Prodrive team to further push the envelope on the suspension front whilst keeping inside the required FIA WRC rulebook.

WRC2003

Tommi Mäkinen revealed a prototype of Subaru Impreza World Rally Car - the WRC2003 at the September 2002 Paris Motor Show.

WRC03  WRC03 copyright © Subaru World Rally Team

"The WRC is now more competitive than ever before and winning rallies demands the very best at every stage. As far as I'm concerned this prototype represents another significant step forward in the development of the Impreza - it is absolutely on the cutting edge," explained 555 Subaru Team Principal David Lapworth. "We've been working on the project for around a year now, and have been involved with our colleagues at Subaru in Japan more closely than ever before. The design of the new road and rally car has been a two way process, with ideas passing backwards and forwards between our design teams. The result of this tandem approach is that changes have been made to the road car which in turn will help us win WRC events."

WRC03  WRC03  WRC03 copyright © Subaru World Rally Team

"The prototype features a number of improvements over the current model, for instance the bodyshell is lighter and stiffer, the aero package uses the air in a far more efficient way and the reduced frontal area makes the whole package more aerodynamic. There are many more improvements under the skin, but until the design is finalised we're remaining tight-lipped."


Group N

 

Group N is commonly regarded as the show room class. The only changes from standard allowed are those made in the sake of safety such as roll cage, full racing seats and harnesses, and fire extinguishers. Alternatives are allowed for wear items such as clutch, brake pads, discs, tires and suspension dampers. Spring rates may also be changed. Another change allowed is the engine management but inlet restrictors mean that ultimate top end power is limited.

 

The car seen here is the TSL/Listers Group N rally car used in the 2000 season. It is based upon a 1993 Impreza RA 4 door, which has been converted over to left hand drive. International Rallying and competition in the European Championships mean that the car will spend most of its time in LHD countries.

 

I had the chance to sit in the passenger seat of the above car and was taken for a short drive and if anyone tries to tell you this is the show room class they are having a laugh! What this car would be like running without the inlet restrictors and with a bigger exhaust and remapped to suit would be mind blowing.

 

The car was still running gravel specification suspension and differentials but had tarmac tires on and boy did it grip! What it would be like with the correct suspension....blimey. Acceleration in comparison to my own P1 was as different as a P1 to a GX/Sport! It topped out quick though due to the breathing restrictions so it was blat-blat-blat up the gear box.

 

What was really amazing was it was not that loud in the cabin and normal conversation could be made... and this was without helmets or intercoms. The Recaros were something else too with a deep bucket and 5 point harness (er how do I do this up?) you were not going anywhere. Many thanks to TSL for indulging us!


 

From 1997 to 2001 Prodrive used the WRX STi Type R as the basis of the group N cars they supply. Interestingly if you want a left hand version they can supply it as standard, something that is not available in the road going Japanese WRX models! Converted at Banbury the cars are immaculatey produced.

Unfortunately accidents do happen, and this car would be reshelled within days ready for a rally the coming weekend. Aparently this car had been borrowed for a driver shake down!

The rally team also has a couple of their own Group N specification cars used for driver orientation of an event. They are also used by teams of spotters running ahead of the rally. Seen here is a Type R with a huge light pod attached to the front of the car.

Richard Burns by David Williams
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Page last updated 29th September 2002
Copyright © 1998/9/2000/1/2 Steve Breen
All photographs copyright © Steve Breen unless otherwise stated and may NOT be copied for any purpose.
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