Project Update for August 1, 2012:
Wow, started writing this Monday and I'm still writing it on Wednesday. Its been a crazy week. The Subaru arrived back from AWD Tuning on Tuesday the 31st, who had it for 3 days sorting and tuning the new motor they built. I am not allowed to share the power numbers until after the race, other than to say it makes "plenty of horsepower" with the conservative tune necessary to complete the grueling PPIHC event. With no car to wrench on our guys here at Vorshlag took the weekend off (much needed!) but got back to work Tuesday morning, after it returned to Vorshlag. Let's get caught up from the last week of work.
More Plumbing and Thermal Protection Updates
Even after my last July 23rd thread update there was still a bit more plumbing to do. The engine bay had a factory late model STi plastic coolant expansion/fill tank, but that made us a tick nervous. It also was plumbed with hoses using worm gear clamps, which Pirtek wanted to change to use threaded ends. We found an aluminum Moroso expansion tank that looked pretty good. When it got here a few modifications were made and this new coolant expansion / overflow /whatever tank was mocked up in the car, as high as possible. Brackets were made to bolt it to the LH strut tower, then another threaded aluminum bung was TIG welded onto this tank (after it was machined down to a reasonable size on the lathe). The modified tank was then mounted and coolant lines plumbed to the radiator and turbocharger, with lines made by the guys at Pirtek. There's an overflow line (tied into the radiator's puke line) if the cap over-pressures as well. The high mounted location of the axillary tank makes the coolant (water only) system that much easier to fill and purge of air. Its also now metal instead of plastic, and has threaded connections instead of clamped.
Below are some shots of more plumbing work, start with the two -6 braided stainless lines and Red Horse bulkhead connectors and end fittings for fuel. These two lines run inside the car (protected from being ripped off by under car debris) along a protected part under the cage, then snake behind the dash and come out through the center of the firewall, away from any heat source.
Some more of our heat insulation solutions are shown below. The main source of heat is, of course, the turbo. It now has a form fitted thermal blanket and the downpipe is fully wrapped in ceramic header wrap.
An picture of the custom oil cooler heat shield is shown below. Here you can see the oil cooler feed and return lines routing very near the (wrapped) exhaust header primaries. A stainless steel heat shield was fabricated with an air gap to the exhaust and also has a shape to keeps these lines routed smoothly away. These two lines have since been wrapped in thermal sleeving and a reflective thermal barrier film was applied to the heat shield on the top side. Next to that picture is a shot of the stock clutch salve cylinder. The OEM "Clutch Delay Valve" (CDV) has been removed and the clutter of 3 OEM hard and soft lines has been replaced by a single Teflon-lined, stainless braided, BrakeQuip hydraulic hose, custom made at Pirtek Plano South. This new clutch line will be also be wrapped in thermal sleeving, as this line was thought to be the culprit behind the mysteriously missing clutch actuation about 2/3rds of the way up the mountain in Brianne's 2011 PPIHC run. No clutch = no smooth shifts. Hopefully this thermal management will prevent this issue from cropping up this time up the mountain.
Other Fab and Prep Work
To work with various thickness wheel spacers, some extra long ARP wheel studs were installed in both the front and rear hubs. With the rear hubs removed it was obvious the bearings were shot, so those were pressed out and new bearings went back in. When the Subaru arrived here it had a full-sized battery (35+ pounds) in the OEM location, way up front. A new Odyssey AGM style battery was picked, a new mount fabricated in aluminum, and it was all bolted to the trunk floor way in the back, for better weight balance. All new 0-gauge cables were made with swedged ends. All new wiring was made to the new fuel pumps, with isolation relays, as well.
see part 2 below...