Monday, January 26, 2009
First off, apologies for taking so damn long to add an update.
Last installment was from Buttonwillow where we broke a throttle shaft. I fitted another but toook the precaution of brazing the plate to the shaft. What I didn't do was braze both sides. That, as it turns out, was a mistake. So an few events later and I'm at Calif, excuse me, AAA Speedway in Fontucky, blazing down the front straight at about 120 when the throttle once again sticks open as I shift into 6th. Instantly shut it down and coast in. I already know what's wrong with it. Turns out you can still break the shaft even when it's brazed on one side. Upon tear down I realized that once again the screw had broken in half with head stuck to the brazing but the threaded portion sucked into the engine. Crossing my fingers I pulled the top of the BP4W manifold (two piece) and very gingerly dropped a magnet wand into each runner. #3 had a tiny little camper, the 2.5m shank of the throttle plate screw. My engine was safe, or so I thought.
So I get yet another TB but this time JB weld both sides in an attempt to keep any detritus from going astray. I install, fire it up and notice some wristpin noise. Lota wristpin noise. Dammit. Maybe running 7400 down the half mile front straight at AAA all day wasn't such a hot idea. So I went back to Buttonwillow a few weeks later to finish it off, which I did at the end of the last session of the day. Seized up tight just as I wound out 5th leaving the esses. :(
Ryal Greenwood at British Car Service in Tucson has made a custom TB for he calls Throttle Zilla. He pulls the OEM 9mm shaft out, bores the TB and installs a very nicely machined 14mm shaft in there, mills one face so it has .5mm less cross section and voila! I'm testing it for him as I know now that shafts only last about two events in my motors. We're also investigating the feasibility of a single barrel type throttle body that will bolt to the stock manifold and the manifold we're working on.
So the OGK now needs a motor. I have a fresh VVT head and 01-05 bottom end in the shop I can mate for a replacement. Good time to work on adapting the VVT head and control systems into the NA6 harness. I'll be using a proprietary ECU with a custom harness. If I can come up with a reasonably priced harness that I can serial produce, I'll offer that as a kit to the public.
While the motor is out, I'll get the Miatacage installed by Drew Staveley
Yes, the same Drew Stavely from Setup. Turns out he can weld and drive, my kinda guy.
Seats going in are Momo Daytonas. 20.3 lbs, Halo, $600 ea on closeout and FIA approved. Oh and they fit. So when everything is in it should finally look something like a race car inside and be about 1000% safer.
Along way we'll be adding the Energy Suspension bushings, OS Giken limited slip and finally, the V8 Roadsters subframe. We added a dual plane APR aluminum wing for Buttonwillow and wow did it make a difference. Going 90 through Riverside in the rain was not something I would have thought possible. The event before that we added an ISC Racing front airdam and as expected the car was a tad loose with it. Adding the wing made the car tight, totally overpowering the front downforce provided by the air dam. What's crazy is even at zero angle of attack, I could feel the wing making the car stick better as low as 60mph. Amazing.
The wing is made up of parts from three different models and the minimum rake was like 10°. So I drilled new holes for the stanchions, put some nutserts in and moved the stanchions wider while I was at it. It's mounted to the body outside of the trunk. No way the flimsy FRP trunklid would withstand the pressure without a bulky support structure underneath. Not being a fan of redundant structure, I elected to mount it directly to the body to save the weight. It's now rock solid and easily supports me bouncing up and down with my entire body weight in the middle of the wing and I have zero added support structure. Perfect. The downside is I can only open the trunk about 10". Oh well, it is a racecar.
So now it needs more front downforce. We'll add a 3" splitter thats sorta squared off on the outside corners. On those corners we'll add dive plane (canards) to help keep air off the front tires. Hopefully that'll balance the car out.
That's it for now. Dinner is waiting...