1990 Toyota Celica GT-Four ST185 Motorsport car

[waveman1500]

This story begins, as so many of them do, with the brilliant idea of going to buy a cheap turbo car. In the dark, and the rain.
After a cursory test drive, I acquired an ST185 Celica GT-Four, complete with boy-racer Turbosmart blow-off valve and 17" chromies. The window tints were peeling, the car stank of cigarettes and I couldn't tell how fast I was going because of the blue LEDs in the gauge cluster. It made horrible scraping noises, but I was promised that a new wheel bearing was on order and would be included in the sale when it arrived. All of this was overlooked, because it was the car from Sega Rally and it went choo-choo!



The initial plan was for the car to be a daily driver, with the occasional opportunity for it to be used in motorsport. At the time I was driving a 1.3 litre Suzuki Sierra, so I was feeling the need for speed!
The photos below show it being used in a round of OZGymkhana, which is a sort of "Ken Block-style" tarmac khanacross with donuts around cones. ozgymkhana.com.au/





In case you are wondering about the two numbers, this is because the car was double-entered, with my good mate Rexy sharing the drive.





We only used the GT-Four once in OZGymkhana, because it was quite eventful! We had a lot of initial teething issues, including the spectacular moment of the car spitting the blow-off valve off the end of the pipework and shooting it about 10cm away into a tangle of hoses, with a disturbing sound which made me fear that the engine had just exploded. The main problem though, was that the handling on tarmac is best likened to a three-wheeled shopping trolley. I blame this mainly on the 25-year-old suspension bushes and dampers, but also partly on the fact that the car is rolling on the cheapest Chinese ditchfinders that the local tyre shop could provide. Here's a
video of the action:



After this event, we have subsequently decided to do all of the OZGymkhanas in Rex's Mini Clubman, which is running a hot A-series race engine on twin SUs and 10" semi-slick tyres.



More details to follow...

[waveman1500]

Having tried the car on tarmac and OZGymkhana, we had well and truly determined that tarmac was not it's forte! For one thing, the tyre wear after a single event was alarming!



Perhaps some dirt motorsport would be more suitable?
The first step on the dirt motorsport ladder is a dirt motorkhana, but they are very rarely run in Adelaide. Next step up is khanacross, and luck would have it that the Southern Districts Car Club had purchased a large block of land and were building their own track on it. I entered the first event at the new track in 2014, which was named the Mid-Murray Motorplex (MMM).



The car was driven to and from the event, and run on the 17" chromies with low-profile Chinese road tyres. Naturally, I had fitted a GFB electronic boost controller when it was my daily driver, so at 13psi of boost we weren't short of power for the short dirt track. The track was brand new and barely formed, so the event was basically cutting straight through the grass and into the sand. As the day progressed, the huge ruts formed in the tight corners and rocks started to emerge from the ground all over the track. As I drove around the track, I could hear rocks pounding the underside of the car, which was protected only by the factory plastic undertrays. Nevertheless, I was sharing the car with Rexy, which meant that bragging rights were at stake! The photos below were taken by Skot from offwiththepixels: www.flickr.com/photos/offwiththepixels/





Rexy having a go:



One of my main inspirations in buying a Celica GT-Four was Michael Clements. He is a long-standing member of the SDCC, and has won many events and championships in it. It was an honour to finally compete against him in my own Celica GT-Four. I even won, because his car suffered an early withdrawal due to mechanical failure. I think it was the gearbox in this case, although he also finished off a turbo in the same season. 



We managed to successfully complete two dirt khanacrosses at MMM, with good results. I was keen for more, but the 17" tyres had cried enough! The tread was breaking up in chunks, and the sidewalls were covered in cuts and chips caused by the rocks in the track surface. As a result, two of my tyres were now leaking quite a bit of air, even after an optimistic treatment with Slime. 

Tune in next time, as I take the inevitable plunge deeper into the world of off-road motorsport, buying rally tyres!

[jeffeRS]

Brilliant write up. I'm glad you saved the car from a life of neon. Kids eh!!. Keep us posted...

[TerraRoot]

love competition stories, and gt-4's, bookmarked!

[hario]

You want actual factual rally tires, or just winter tyres as a cheap alternative perhaps?

[waveman1500]

Feb 17, 2015 15:06:00 GMT hario said:

You want actual factual rally tires, or just winter tyres as a cheap alternative perhaps?

In South Australia there is no need for winter tyres, and therefore to obtain some as a special order would be far more expensive than the option that I chose - used rally tyres!

There were two obstacles to be overcome in procuring rally tyres for the Celica. First, there are the tyres themselves, and secondly the rims.

I have never seen rally tyres advertised for sale locally on Gumtree or eBay, but there are plenty out there if you know who to ask. I made a request for help through the Southern Districts Car Club's Facebook group, and found a club member who is very serious about his motorsport. He had a lot of part-worn rally tyres in various compounds. I met up with him after work one day, and shook his hand on a deal for four Pirelli P-Zero K6 rally tyres, which is a soft compound. They had a bit of chipping to the treads, but there was still some life in them. Crucially, the main benefit of using rally tyres is the carcase construction. Rally tyres have very strong sidewalls, which are protected by a thick layer of rubber. This should help them last a lot better than my 17s! They came covered in dirt to prove that they'd been used, so the most painful part of the operation was having to squeeze them into my new daily driver, a 2002 Subaru WRX STI. I had to put one in the back seat, but luckily I had my swag in the car, so I used that to protect the interior.



The next part was to find some 15" rims to mount the tyres on. Celica GT-Four wheels are rare, but they have a 5x100 PCD like a Subaru, so my first port of call was to go to U-Pull-It in search of some 15" Subaru alloys. I duly found an old Liberty with 15" ROH wheels on it and liberated them. Whilst I was at it, I noticed that the spare wheel in the boot of the car looked like it had never seen the road before, because it is a steel spare. Having added that to my trolley, I grabbed a second spare from another Subaru to make a pair. Then came the task of fitting six full-size wheels and tyres in the boot of the Celica, in addition to the original spare. Amazingly, they all fitted in there, I didn't even have to move my seat forward!



This is where I ran into a problem, because Subaru use an extremely high positive offset on their rims (+55mm). I knew this from the beginning, but was hoping to be able to make it work. Upon offering the Liberty wheels up to the Celica, I found that the spokes hit the front brake calipers, but on the rear it was possible to fit them. The plan to fix this was to use spacers. As a mechanical engineer I strongly dislike wheel spacers, but I figured that they should be okay, as long as I didn't use them on the road. To this end, Rex and I fitted longer wheel studs on the front, and ordered a pair of the widest five-stud spacers available from the local parts shop. Of course, the fitting of said spacers came down to the day before our first Rallysprint! Once I received the spacers, a big problem was immediately apparent! The spacers were not designed for such a small PCD, most likely having 5x114 as their minimum size. The centre bore in the spacer was so large that if we elongated the slots to fit the wheel studs, there would have been no metal left to support the wheel. I don't have any photos, but just imagine two men throwing things around in a shed with a lot of foul language! It was a major hurdle in our rushed pre-event preparation. I knew only one way to fix the problem quickly - find some GT-Four wheels.

There was only one GT-Four enthusiast I knew who might be able to help. It was fairly late on a Saturday night, but I called him anyway in desperation. By an awesome stroke of luck, he had a set of five original GT-Four wheels which he was willing to sell. Not only that, but they already had rally tyres fitted! Feeling that it was too good to be true, I jumped in Rex's Subaru Liberty GT wagon and headed across to the other side of town. I think it was after 10pm when we arrived, but my GT-Four loving acquaintance was happy to see me. He had entered a similar ST185 GT-Four into the Henry Lawson rally the previous year and had an off, which broke the suspension and twisted the front chassis rails. One of the rims had a slight buckle and didn't hold air, but luckily he also had a rally tyre on the spare wheel. They were Pirelli P-Zeros, exactly the same as the tyres which I already had, but if anything they were in better condition. When I was offered a price that was less than what I had paid for four tyres alone, I couldn't shake his hand fast enough!

So, the state of play after a week or so of rushing around buying tyres was this:
4x alloy and 2x steel 15" Subaru wheels bought, which don't fit any of my cars
4x rally tyres bought, with no rims
5x Celica GT-Four rims bought, with rally tyres fitted!

All in all, several stacks of tyres had consumed every spare centimetre of space left in my shed! It was all worth it though, because on the morning of the first ever Rallysprint at Mid-Murray Motorplex, we were there with bells on!



To keep everything chronological, I'll be updating the earlier posts in this thread with a video and a few more photos, so please check back at the top of the page if you're interested. Thanks to everyone who has commented, it makes writing the thread worthwhile!

[JC]

Cool write up, enjoyed reading!