Welcome to our featured cars section. Here we give you the low down on on some of the cars that we have upgraded and engines that we have built or rebuilt and even give you a chance to have your say about what mods we have done to your car. If you wish to be named then let us know otherwise names will be changed or removed to protect the guilty!!
Another owner who also has a JDM Subaru Impreza STI Wagon 2002.....
In 2003 my car was imported into the UK almost new (only 5k Japanese miles) and I have been sole owner in the UK. The car is an everyday road car used for relatively high mileage (up to 20k miles/year) with occasional track use.
Modifications have gradually developed over the years with a variety of turbos (VF30, MD195 and MD321H) with remapping using Ecutek software.
Power has developed from the stock 280 bhp to slightly over 400 bhp with the MD321H. These modifications have all been based on the original JDM STI 2.0L engine.
The need for a rebuild
By early 2008 the car had covered approx. 85k miles, comfortably pushing out over 400bhp for the last year with no issues on the standard engine. However, on the standard engine at this mileage, and with the MD321H setup and supporting mods, there was clearly little headroom for improvement in the power stakes. The next obvious step was to go for a built engine.
My main decision was whether to stay with 2.0 or go for 2.35 or 2.5. The 2.0 route was quickly ruled out since more power would only result in a laggier car. It was therefore a question of 2.35 or 2.5. This took some time to make a decision since the large majority of road cars were opting for the 2.5 route based on improved torque and low down spool, making it a very usable road car.
However, due to my driving style I had always loved the revvy nature of the 2.0. My objective was to find an engine that would rev like a 2.0 but spool up quicker, provide more torque and power, and be extremely strong with the facility to take power up to 600bhp. The 2.35 setup therefore seemed the obvious choice for me.
Based on his reputation with 2.5 builds I decided to discuss a 2.35 build with Len at Subaru4You. This would be the first 2.35 build for Len using his own spec. Len came up with several options of achieving 2.35. The first option was to use a 2.0 CDB then bore & liner this to result in 2.35. The second option was to source an EJ22T CDB, machined to take centre thrust with stroked pistons and rods.
The problem with the second option was the availability of EJ22T blocks which are very difficult to source. Luckily, Len managed to source a brand new EJ22T together with JE pistons, Carillo rods, 2.5 STI crankshaft, Cometic head gasket set, ARP 12mm head stud kit, S4Y oil pump, Kevlar timing belt, ACL Race main/big end bearings. A full build was then developed, agreed and started with Len in early May 2008.
Whilst speccing the build with Len, I had also been considering turbo options. Because the car would still be my everyday driver I was looking for a turbo which could provide power in the region of 450-500 bhp. The obvious choice was the proven MD321T. It was suggested trying the brand new turbo. This unit would be similar in performance to the MD321T but with the hot-side ceramic coated.
By end of May 2008 Len had completed the build including installation of the new turbo. The car was collected and then mapped on standard ECU for running in. For the first 1000 miles the car was run on mineral oil, then switched to semi-synthetic. At 1500 miles we switched to full synthetic.
On 21 June 2008, at 2300 miles, the ECU was replaced with Simtek and remapped up to 1.8 bar peak. However, problems were encountered during the final stages of mapping with a new uprated Walbro fuel pump which resulted in aborting the mapping session. This was a real blow as I was hoping to go to the Nurburgring in June! Given the logistics of obtaining a replacement pump, fitting and remapping there seemed little chance of completing the car for the Ring.
On Thursday, the pump was fitted by Subaru4You, then a ‘special slot’ with mapping that evening to finish off! By 10.30pm mapping was complete & I then headed down to Dover to catch the 7am ferry the next morning for the Ring trip…. how close was that!!!
The first 3 months
The 2.35 was a huge improvement on the Ring trip of the previous year where the car had been 2.0. The increased power, torque and spool meant the car was much quicker and far more usable through the gears and in corners. The same revvy nature is also just what I wanted. This has meant that the car has been massively improved on the road as well.
There has been a lot of fine tuning over the initial months. This is the inevitable side of a rebuild and one that shouldn’t be under-estimated beforehand. I have had several map tweaks to cure turbo surge, plus upping the boost to 2.0 bar. I have also had spark plug failure which wasn’t readily identifiable and ended up with the car being recovered to Len’s for diagnosis. Combine that with idle control issues and other minor tweaks, there has been a lot of effort required from all to complete the car fully.
All in all, the build is exactly what I’d wanted resulting in a very usable daily driver. Subaru4You have done a great job and their after-build support has been second to none.
The car has now completed around 8k miles and is running superbly and is driven hard often with negligible oil usage. I have every confidence that the car is a reliable build and is comfortably delivering between 450-500 bhp.
On the road current spool times in 5th are 1 bar at approx. 2800 rpm with full boost of 2 bar at approx. 3500 rpm.
[PICS BELOW - CLICK TO ENLARGE]
And the results of your dyno run