APR will be hosting a domestic vehicle open house on June 20th, 2009 to showcase new products for the Mustang, Corvette, and Viper. Over a dozen street and track machines (including some non-domestic vehicles) will be on display. There will be free food and drinks, and over $3000 worth of raffle prizes.
Spanning up to 67", with a 12" chord, the APR GTC-300 airfoil is the most aggresive and efficient airfoil in APR's entire line-up of airfoils. Yes, the GTC-500 airfoil sits wider, at a span of 70", and looks more aesthetically-pleasing when mated with the wider Vipers and Corvettes, but you just can't beat the lift to drag (L/D) ratio of the GTC-300 airfoil.
We'd write all about what kind of numbers the GTC-300 airfoil puts down, how to read and understand those numbers, and what kind of angles to run, but APR already has an entire page dedicated explaining all this already. Take a look!
See the new Gurney Flap (wickerbill, or whatever you want to call it, etc.) on the APR GTC-300 airfoil? http://www.flickr.com/photos/linnick/3584593960/sizes/o/in/set-72157619142962881/
This flap increases the effective camber of the airfoil and increases the maximum lift coefficient (Cl-max)...which translates into more downforce at the same angle-of-attack (AOA) vs. not having a Gurney Flap. Also, coefficient of lift (Cl) is increased most likely increased, but coefficient of drag (Cd) could either be increased or decreased vs. not having the flap. Can't confirm it without CFD simulations. In any case, lift to drag ratio L/D is going to be higher with the flap than without the flap. This type of "aerodynamic tuning device," in this application, typically makes no more than a small (~5%) difference in downforce.
The one pictured is a prototype piece. The carbon weave pattern is different from that of the airfoil's. Of course, the production piece will have a matching carbon weave pattern. Can a driver "feel" a difference with the flap installed? Unlikely. Does it look great and make the already huge GTC-300 wing look even bigger? Definitely.
Arrived late Saturday evening at the Town House motel in Lancaster, on Sierra Hwy, just south of Avenue J. A bunch of folks, including Manly Kao, Ed Lee, Kevin Feng from Buddy Club, and friends were chillin' and drinkin' outside. Manly was "pretty buzzed," as he would keep repeating to himself. :) Stayed in Manly's 1-King bed room, slept on my cot and in my sleeping bag...he said he "rolls around a lot" so sharing the bed was out of the question...for him. :P AJ Latteri arrived a bit later, and took a spot on the floor.
Guy taking a picture of me taking a picture:
Kevin Feng and friends from Buddy Club:
Booze bar:
Manly Kao, "buzzed"...
AJ in his corner:
Sunday morning, got to track, set up, and signed in. Manly and AJ took advantage of the sun and dust storm shelter of the enclosed trailer for most of the day. We saw some E-Z UPs fly away. Manly was there for Street RWD, AJ and I were there for Modified RWD. We were alotted 2 morning practice sessions and 2 afternoon time attack sessions.
The rig and the car:
AJ's rig:
1st practice session, got in the car and got to the hot pits, set the boost to 11psi, and heard a very loud "PPSSSSSHHHHHH" just as I made it past the pit walls. Got boost? Nope. Got around the track slowly and back to our spot. Turned out that the charge pipe had blown off at the turbo compressor outlet. Realized that I should have checked that connection -myself-, because that connection had always had a history of not staying on when anyone but me did the connecting. Oh wells, I'm not gonna blame anyone...water under the bridge. Didn't have enough time to get back out during the same session. Decided to check and tighten a lot of other air and water connections.
The car:
2nd practice session, turned the boost down to 6psi wastegate only (~160whp at wastegate), went out again and got about 4-5 laps before running low on fuel. Smelled burning oil and smoke leaving the back of the car. Initially thought it was just the left-over oil that pooled up in the exhaust from the previous motor, but then I saw smoke coming out from under the hood. Well, good thing I had to leave the track to refuel anyway. So I got back to our spot and checked under the hood again. Hmm...I didn't see anything wrong at first. The oil catch can was empty, and there wasn't any sign of oil leakage...until I checked the oil catch can blow-by tube. OMG. The re-inforced transparent tube had melted...right after the fitting on the valve cover gasket. Oil, along with the melting tube, had dripped down and burned off the turbo manifold. Wow. This was the tube that came with the Greddy catch can! Replaced immediately with a proper oil cooler-spec. hose. Added some oil. Lunch break.
The spot:
Time attack session #1, set boost back up to 11psi (~210whp), saw oil burning smoke again (Manly later told me he heard the announcer talk about my smokin' car...hahaha), got worried, fiddled with the boost controller, accidentally set it to 15psi, then finally back to 6psi. Didn't smell any oil burning so figured the smoke must have been from the left-overs in the exhaust. Felt the car exhibited a bit more understeer than I would have liked. Ended up being so slow that the car behind me had to pass me. Hot lap fast time ended up being a very slow 1:45.xxx. Got back to our spot and sniffed around some more, but didn't find anything wrong with the engine. Noticed the open ducts brake duct (foglight?) openings on the bumper doing nothing but letting air into the wheel well. Decided to seal up those openings with cardboard and tape to help with front-end downforce.
Front-end aero mod, with a little help from Mickey Mouse:
Time attack session #2, back out to track, boost controller happily set to 11psi. Uneventful warm-up lap, increased the speed on the hot lap, smelled absolutely no burning oil, and saw no smoke from the exhaust. So I decided to focus the majority of my attention on driving (as opposed to staring at the gauges all the time) and picked up a bunch more speed. Couldn't tell how much the cardboard and tape was helping, since I changed up the power settings and my driving, but it still felt "better" to have done it. :) Caught up to the car ahead of me and ended up with fast hot lap time of 1:40.725, good enough a last place 10th out of 10 finish in Modified RWD!!! :P (next time at Big Willow, ima go much faster...I promise!)
Getting the car and everything else prepared for the track, driving on the track, fixing the car at track, and having the "shakedown day" coincide on the same day as the "competition day" can be quite tiring and stressful at times (especially when the car was broken at RTA Buttonwillow 2 months ago), but being able to drive on track and chillin' with some track buddies made it well worth my efforts. At the end of the day, I was just happy to have gotten through it without any major problems and without a broken car. And now that the car is working and ready to drive again, I'll be hitting up the tracks with Speed Ventures (http://speedventures.com/) at least once or twice a month, plus doing some drifting with Drift Association (http://driftday.com/). I should have plenty of time to fully test and sort out the car during the hot summer, in preparation for the next Redline Time Attack event at Spring Mountain (Pahrump, NV).
Here are some pics taken by other photographers who were there to capture the action. The authors were kind enough to allow us to post their awesome pics here:
Got the Baby Monster back from Hiro's Auto Repair this past Thursday. Freshly bored block, new Wiseco pistons, new rod bearings, new main race bearings, new HKS 2mm metal head gasket, new miscellaneous engine parts, new Greddy 1L aluminum oil catch can, and simplified/proper water routing. Re-used the head, R&R billet connecting rods, OEM forged long-nose crank (with WPC Treatment on the nose). Assembly and clearances checked by the machine shop. Crank balanced, valve job, etc. Billet main caps from previous build could not be re-used, so back to OEM main caps now. Driver-side valve cover breather plumbed to new catch can. No WPC Treatment this time...no time. It should be fine, now that the cooling system is done properly. Broken on the turbo manifold from 2008...still broken.
New 55mm Koyo radiator swapped in on Friday. The 1.5 year old 37mm Koyo from had sprung a leak in the core somewhere. Charcoal canister removed. Greddy water expansion tank relocated to where the charcoal canister used to be. New prototype carbon Gurney flap added to the APR GTC-300 airfoil. A lot of oil smoke was coming out the exhaust...thanks to the cat and muffler being filled by oil from the previous motor. New OEM 323GTX PCV valve put in. Dumped the nice ENEOS synthetic oil (from Hiro's Auto) and replaced with 10W-40 Valvoline dino oil for the break in. Tried to do some break-in in front of the office, but turned out to be very inconvenient due to very limited space. Changed the oil again after incomplete break-in. Dark oil out.
Today, finished complete break-in at private testing facility per instructions at http://mototuneusa.com. Took it easy and ran with 11psi (~210whp). Got the Greddy boost controller settings just right for very, very quick response at 11psi. Set this as the "Lo" preset. Set the "Hi" preset to around 15psi, but wasn't able to get the settings just right...oscillations at 13-14psi before arriving at 15psi. Not in the mood to run 17psi yet (previous "Hi" setting was at exactly 17.3psi, putting down about 265whp). Water temperatures and oil pressures seemed fine and stable during over 30+ miles worth of very hard driving at the site. More tendency to understeer while cornering around 40-50mph, as the effects of the downforce from the GTC-300 wing would begin to set in. The extra understeer would go away at 60+ mph as the lift reduction due to the APR carbon/Nomex honeycomb splitter would begin to take effect (got dead bugs on the splitter). Very stable in a straight line at 120mph, but at 11psi, there wasn't enough runway to get much over 120mph. Did some big manji drifts and spun out...handn't done any drifting since early-mid 2008...only a bit rusty...har har. No more smoke from the exhaust...most of the oil in the muffler must have burned/blew out. Changed to fresh dino oil and new filter after the break-in/testing. Light-colored oil out. Found shiny metal shavings in the oil filter as expected. Piston rings should be sealing well and cylinder walls should be super smooth now.
Just finished dinner. Leaving for Willow Springs Raceway in a few minutes...
