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Unread 08-04-2012, 07:21 PM
Fair!'s Avatar
Fair! Fair! is offline
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Join Date: Jul 2004
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Default Re: Brianne Corn's Pike's Peak Subaru STi

Project Update for Aug 4, 2012: Final thrash underway for the trip out to Colorado Springs that leaves tomorrow. The last few days have been a blur. I just worked a 25 hour stint and got back to the shop after a few hours sleep. Please forgive spelling/grammar/logic errors in this post, as we're all having trouble remembering what happened. Final hours of prep are here!

More Exterior Prep

I think Ryan had finished metal work on the right rear fender where we left off. From there Ryan finished up welding the left rear flare, Big Paul helped with some metal grinding, and I got to work on the bodywork on the right rear. This is the one with the fuel door and was extra fun. I started on this at 7 am Friday morning, knocked that out, we went to the test (more on that below), came back and I worked through the night on that plus the left rear. I suck at body work - we don't normally do this work - but it's done and they are wrapping the car now.

Don't ever try to make exaggerated OEM steel flares like this on a Subaru. Just cut for the tire clearance you need, buy composite flares and slap them on. This was an epic amount of work - like 150 man hours or more. Not what you do for race car flares.

Matt has been working on the hood, hood scoop and bumper cover wrapping for the last 2+ days. Amy and Jason are jumping in now to help cover the rest of the car now. Lots of work to do.

I left the shop at midnight on Thursday but Matt and Ryan were still going strong. We had talked... talked about replacing the OEM rear wing but there just didn't seem like we had time left to get it on, do some testing, and make the matching front splitter. Well I made it back into the shop at 7 am on Friday and saw this monster bolted to the trunk. They took the GTC-300 carbon wing from my Mustang, mounts and uprights as well, and made it fit Brianne's Subaru. Fit perfectly, bolts securely to the full steel trunk lid, and the forces go right into the rear fenders/chassis. Massively strong uprights - .250" thick 6061-T6 plates. Trust me - we've heard all of the suggestions on Facebook already: No, it doesn't need cables or guy wires or more structure. The same wing worked fine on my Mustang just bolted to the trunk, going into Turn 1 at 150 mph at Texas World Speedway, and it worked on the Subaru in testing at 130+ yesterday. No shimmy, no shake, and it isn't falling off.

More Race Prep

Thermal wrap is still going on in many places. The ECU is still in the factory location, under a metal "shoe rest" in the passenger foot well. To keep heat from the ECU and the navigator's feet we've covered this section in thermal insulating blanket, sealed to the floor. The downpipe is fully wrapped, too. No more melted shoe soles.

Making it up the mountain without overheating is difficult. This will be the single biggest failure point for new and old teams alike. I suspect it will take out 50% of first time Pikes Peak teams. One trick for combating the heat of the thin atmosphere going up towards 14,000 feet is spraying water on everything, the whole way up. About a mile into the race co-driver Jeremy Rowland will flip a switch and turn on the pumps, and the two spray bars will mist water in front of the massive Perrin front mount intercooler and the CX Racing aluminum radiator. They tested the flow rate of the pump and found a water reservoir that slightly exceeds the amounted needed for the ~11 minute run. It is mounted securely with straps that go into anchors in the chassis.

On Wednesday I took a 4x8' sheet of .063" aluminum to Janco Fabrications and borrowed owner Kurt's sheet metal brake and sheer. Took the templates Ryan made and cut out a rear bulkhead and top shelf, separating the passenger compartment from the trunk, which has the fuel filler neck, fuel tank opening, and fuel pumps. Mike from Pirtek helped me cut, mark, drill, trim, and install both pieces. We must have had them in and out of the car 20 times - you know how it goes. Both pieces bolt in to existing holes and they bolt together. Aluminum tape will seal the edges and rubber will surround the fuel lines and battery cables shown passing through.

I kind of screwed up when I bent the top piece, so instead of taking the sheet back to Kurt's and making the bend angle again, we made a home made "sheet metal brake" with our 1200 pound fab table, some angle iron, and a crap load of clamps. It was pretty ghetto but we got the bend right. When its midnight you do what you gotta do.

Somewhere in there our fab man Ryan made a new exhaust from after the downpipe, during the wee hours of the same night he mounted the rear wing. Its made from the normal 16 ga 304L stainless, 3" mandrel bends and strait pipe we keep in stock for just such occasions (we also stock 2.5" and 2.75" bends, V-bands, and poly hanger mounts). No muffler, as per AWD Tuning's request - makes more power, and makes more bark. It is loud but it sounds like a proper race car!

Friday... no Thursday morning? I worked on the inner fender panel structure welding, covering the big gaps made when the rear fenders were sectioned and mounted outboard 2". These make the fenders rigid once more and keep water and crap out of the trunk and passenger compartment. Had to do the rear doors also. Seam sealer normally goes over these joints and it all gets painted (but not today - out of time!) The AST 5100/6100 suspension was on and ride heights were tweaked Friday morning.

The car was corner balanced, race aligned, and fluids were topped off. With driver and co-driver it is sitting at 57% front bias - not bad for a AWD car with the motor way out in front like this. The rear diff was removed Wednesday night, taken to AWD Tuning, and their techs installed a new OS Giken rear differential that was another sponsored part for Brianne's race effort. Ryan reinstalled the diff, Motul synthetic gear lube went in, Amsoil went into the motor, and it was fired up once more.

Quick Track Test

With the rear bumper & brake lights still removed and barely started rear bodywork, we loaded up the Subaru into the Vorshlag trailer and headed out to the Mineral Ring, a 60+ acre asphalt site we rented west of Ft. Worth, about 2 hours from our shop (2.5 hours with some construction traffic). Not ideal, but Eagles Canyon Raceway was down for repairs and the folks at MSR were none too friendly with my requests to rent some track time that day. We made the trek to Mineral Wells, unloaded the car and set-up a crude course layout (approx 1.5 miles long), sort of following something the drift crowd had run there recently. Tried to test elements that Brianne might see on the mountain: medium speed corners, some low speed stuff, and one faster straight/turn to check the rear aero.

Ryan and (Brianne's crew chief) JasonM checked all of the systems and I drove the car. This was because Brianne couldn't make it on Friday for this systems check, I fit the seat width and location set-up for Brianne, and had tested in 500+ whp race cars at this same test site. We had one set of practice tires (from my DSP BMW at the 2010 SCCA Solo Nationals) and another set of 285 A6s mounted to 2nd set of Vorshlag/D-Force 18x10 wheels (one of her two sets of race/quali tires). The testing itself was brief but productive: two sets of recon laps to get everything warmed up, then two sets of hot laps. The guys used an IR gun to check temperatures then pyro'd the tires to see how our pressures and camber settings looked.

Video of session 1 (1 lap): Link
Video of session 2 (4 laps): Link

First video is short, the 2nd is about 4 laps and a little more exciting. The site was DIRTY and we didn't have the time to clean a good line, so we made do with what a course we could set up quickly. I don't pretend to have half the driving talent of Brianne, but maybe enough to at least get a feel for the car. The car felt great: it makes PLENTY of power (thanks to AWD Tuning), grip was excellent, the R4 Porterfield pads bedded in nicely, and all systems were in the green. On my 2nd set of hot laps I ran over something and cut a tire at the end, so we wrapped up testing and loaded the car back into the trailer before the tire went completely flat. Didn't want to risk cutting a new tire on this dirty course. That's all we really wanted to do - a handling check and a short stress test of the mechanical systems and see if anything broke. Nothing did. Win.

Grabbed some food on the way back and made it to the shop by 9, then we all worked all night. Sure, a day at a proper road course with Brianne at the wheel and the car 100% prepared would be ideal, but we always knew that with the timeline we had this wasn't likely. The crew does have a few days in Colorado (to rent PPIR or during practice on the mountain) to fine tune things a bit, but I feel like the handling is very close and everything else felt spot on.

Last Little Bit!

Brianne is now here and joining the crew, already hard at work. We're all going strong but they are debating some last minute additions that could help make Brianne's race effort that much faster, but it would eat into the "one day buffer" built into the transit time going from Texas to Colorado (16 hours one way). That's a day that could be used to acclimate to the high altitude in Colorado Springs, a day to deal with any transit problems on the truck trailer (which I feel is low risk, being that both are in top shape/have new tires/etc), or a day used in our shop to build more go-fast goodies into the Subaru. Some things can be finished up on site, but big things cannot.

Decisions, decisions...

That's all I have for now. I will post up one more update covering the last of the Vorshlag shop prep, and of course a big post after the event itself.

Stay tuned!

Last edited by Fair!; 08-31-2012 at 08:33 AM.
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