This was my first Subaru and I imported it from Japan. It was in very good condition for its year (MY95) and clearly well looked after but I was not impressed with the performance which I thought was over rated and fuel consumption was disappointing. Poor weather ability was great.
GGR fitted a Sports Cat exhaust and cone filter at some preposterous price but I did not know a lot about Scoobies at that time. In hindsight, this was a big mistake.
George Smith (who was then at Falkland Performance) suggested a chip as a cheap way of getting more power and he spent a lot of time setting it up. Now the car performed in line with my expectations but when driven sensibly there was the bonus of improved fuel economy. On a few occasions it returned 31 mpg. 29 mpg was not difficult to obtain on a run and with mixed driving somewhere between 25 and 27 mpg depending on the amount of town driving and cold starts.
I carried out minor improvements including lights, a very cost effective brake mod, the fitment of some instruments but essentially the car remained in this format until the beginning of 2004 and I was happy to drive it during periods when my STi Wagon was undergoing "more mods", trips to the farm, lugging gear about or journeys where a 25% fuel economy improvement over the STi was appealing.
In November 2003 the car produced 250 bhp and 260 ft.lbs at Well Lane on the same day the STi did 585 bhp and 464 ft.lbs. At Elvington the WRX ran 1.914, 13.98 at 87 mph with a top speed close to the rev limiter of 136.9 mph, reached a good distance before the 1.25 mile mark. The speedo was around 150 mph. So while this performance was reasonable it was nothing startling.
Over the Winter I decided to carry out a "budget mod" to see what could be achieved for as little expenditure as possible bearing in mind I already had a number of parts sitting in my garage. Everything was put together with care and lots of attention to detail. The turbo was clocked to allow straight discharge of compressed air to the FMIC pipework and it set back for swept entry. Making the up and down pipes was an absolute nightmare. Sale of the GGR exhaust with Cat and induction kit funded the replacements with money left over and individual oil temperature and pressure guages made way for a combined Mocal unit freeing up space for the autometer AFR guage. With the Link ECU I dispensed with the MAF sensor and the induction system consisted of a �35 K+N filter and a swept stainless steel exhaust bend made up at the local exhaust and tyre depot. In total there was change out of �50 including the filter.
REVISED BRIEF SPEC:
Walbro 255 lph pump plus FSE FPR ( �195 - AS Performance)
Revolution 3" exhaust (off the STi)
Roger Clark open neck 3" downpipe.
Tubular headers and up-pipe. Gas flowed. (Gruppe 'S' second hand from Andy Forrest).
TD05-06 20G
550cc injectors
K+N filter (�35)
Hybrid FMIC
GFB Pulleys (Jap Innovations)
Link ECU via a swap with other bits from Bob Rawle.
Hand held Link Engine Management unit from STi.
Knock Link from STi.
Autometer AFR (Scoobymania)
Mocal boost guage (Burton Performance - �35 ?).
Combined Mocal oil pressure and temp (�58 )
Nomad digital induction charge temperature (�50)
ADDITION TO SPEC:
STi 6 gearbox (from STi 6 Wagon) with front LSD and new DCCD with laptop programmable ECU.
(This was an interim spec and has been further revised for more power).
Once I had a Wideband O2 from Andrew Carr I was ready for mapping.
A run at Elvington gave 2.152, 13.53 at 109 mph and 140.4 mph at 1.25 miles with a slightly raised rev limit and the speedo well past 150 mph. Top speed was achieved at about 1 mile. The 1/4 time was a little disappointing but was straight out the box. Some further work was done resulting in a dyno run with 399 bhp and 358 ft.lbs at 1.45 bar. The torque was impressive, so much so that I soon broke third gear on the TY752 gearbox. This was replaced with the original unit from the STi 6 Wagon along with the exisiting RCMS flywheel and AP racing organic uprated clutch. I decided to stay with the OE 4.11 diff ratios but the gearbox change made the car far more enjoyable. With the lighter flywheel greater precision was required for a good launch and more care was needed when adjusting tickover.
A subsequent visit to Elvington in complete road trim and a full tank of fuel gave 1.916, 12.92 at 107 mph and 160.9 mph at 7000 rpm. Again top speed is reached well before 1.25 miles and is only restricted by the rev limit and gearing.
With fine tuning there is more to come from this set up but I needed to fit an EGT guage to assist with my mapping but the project showed what can be achieved for reasonable expenditure on an old Wagon. With a higher rev limit will come higher top speeds through the 1.25 ml trap and mid 12`s should be possible next year.
Until now the car had been on original wheels, Goodyear NCT5 205 50 16 tyres and standard suspension. Shaun at Halfords Team Valley supplied 7.5" x 17" Super Leggerras, Eibach springs and Toyo T 1 R`s and AS Performance provided an anti-lift kit, camber bolts and Whiteline rear ARB and the suspension was set up by Tristan Pye of John Pye Motorsport and the difference was truly amazing.
During the project particular attention was paid to detail and care taken with heat management to ensure the car approached its potential.
ADDENDUM :
A few months after the WRX had 400 plus bhp with enhanced fuel (385 bhp on Optimax and 1 ml per litre NF) when the TY752 VB3FA O/E gearbox broke third gear. This was quite a dramatic occurence when the wheels locked up and the poor motorist some distance behind was confronted with a smoke screen and very narrowly avoided a rear end shunt.
An STi 6 TY754 box complete with front LSD was fitted to the WRX and this transformed the vehicle. The taller ratios made good use of the power available and cross country journies even in the rain could be accomplished incredibly quickly. The STi box had already done 31,000 miles at over 400 bhp in my STi 6 Wagon and perhaps 20,000 of these were with an excess of 500 bhp available. The box was already noisy but it had stood up well to numerous drag starts and when it became particularly noisy we removed it at John Pye Motors. I was amazed to see that the gears had no wear evidence whatsoever and as part of the overhaul we replaced the rear section, viscuous centre diff with a new DCCD complete with its own programmable ECU. Using my laptop this has 5 programmable positions with '0' being fully open, '5' being fully locked and any variety of mappable settings in between. The handbrake now releases the diffs and it is possible to execute very neat handbrake turns.
I have done a lot of under bonnet heat management and with the Hybrid Front Mount Intercooler I am achieving induction temepratures at the throttle body equivalent to ambient temperature. The car now maintains ambient induction temperature up to 4500 rpm in the cruise and with this additional heat management work the Hybrid Tube and Fin FMIC now out performs the APS Intercooler fitted to the STi 6 Wagon.
FURTHER UPDATE
When first fitted the car was running around 380-410 bhp subject to the map on Optimax or with the use of Methanol but it was decided to rebuild the engine with STi 3 heads which I ported myself. My own Mark 3 ported headers and purpose designed uppipe were fitted in place of the tubular GT spec and this greatly improved spool. One of my own TD05-06 20g turbos was fitted, ported to the uppipe and turned through 180 degrees to discharge directly in to the intercooler pipework. With a Simtek ECU at .15 bar less boost this car now produces 422 bhp and 355 ft.lbs with more to come on V-Power plus 2mls per litre NF. The factor limiting the power is the turbo. 454 bhp has been achieved with race fuel but it is intended to fit an alternative turbo to allow the car to run in the 450 - 500 bracket on V-Power plus NF at 2mls per litre.
There have been further developments on this vehicle which will be reported in the near future.