Undertray

Here you can see a large gap between the floor and the diffuser. I was concerned about the diffuser acting like an air brake and needed to fill the gap.

And looking at it from the back of the car. I made a template out of poster board and cut the flat undertray out of 22 gauge aluminum.

And here it is in place. I would probably benefit from a piece to cover the driveshaft tunnel but that will have to wait for another day.

Testing the improvements

I had a very bumpy abandoned runway to test out my changes the other day. The new front sway bar and changes to the rear motion ratio seem to have done exactly what was expected-there is much less body roll and quicker reacting handling but it's also less forgiving. I went from full soft to full hard on high speed compression and the car felt most controlled somewhere in the middle. I tried stiffening low speed compression on the back only and the car went from planted to tail happy pretty quickly. Full stiff on the rebound seemed to reduce traction but adjusting to the middle felt right. I suspect the whole set-up is just a little too stiff for the very bumpy surface but I'm pretty optimistic for Nationals. I am concerned about the lack of traction off the line and under hard braking. The car has 93% anti-squat and I can raise or lower that with an adjustment of the top bars on the 4 link, I think I want to try lowering the AS number to improve braking performance. I also have an oil leak and the back of the rear spoiler and expansion chamber of the diffuser seem to have sucked up every drop of it-a good sign that the aero is working, I think. And it looks like I will have to vacuum out the interior of the car after every event because it fills up with small rocks kicked up by the slicks. Here are a couple of short videos, pardon the audio, I forgot to plug in a mic:
acceleration test  http://www.youtube.com/watch?v=9Yqpc0-8k8U
slalom test  http://www.youtube.com/watch?v=SZPos62DFw0

Oil Cooler

I may need an oil cooler but don't want to run one if I don't have to because of the extra weight right on the nose of the car. I bought a stock XK12 oil cooler off e-bay and it just happens to be the same width as the radiator I have in the car. The problem is that I have no place to mount the cooler. I have the space in front of the rad, just nothing to attach it to. I decided to build some prototype pieces that will clamp to the radiator side tanks and once the concept is proven, I can get lighter ones made from aluminum.

The front side of the U shaped clamp with the oil cooler bolted on

The back side of the clamp with a bolt to tighten it and a piece of scrap aluminum to spread the load across the radiator

Here is a shot of the whole oil cooler in front of the radiator

And it's right behind the lower opening in the spoiler for maximum airflow

Front Sway Bar

As great as the car felt last weekend, looking at pictures of it on course showed me that the Pink Panther suffers from a little too much body roll. I did not have a front sway bar so I decided to mount one.

Here is the stock MGB-GT front sway bar, which happens to be correct for the car

The ends use a rubber bushing but they are too soft for this application

So I pressed them out

And pressed in an aluminum replacement

For the mounts I picked up some .75" x 1.25" aluminum and cut it 3" long

Then drilled holes to bolt to the car and one that is .625"-the same size as the sway bar

Then I sliced it across to make two halves that clamp over the bar

I still need a place to bolt the mounts so I also picked up this aluminum angle and cut it into 3" pieces

Here is the mount bolted to the angle. Notice I stamped a 1 into the mount, this is to ensure I don't mix up any of the pieces

And here is the bar bolted to the mounts

There are thin washers between the two halves to provide the right amount of tension on the sway bar

And the end links are just .75" square tube with a right hand and left hand nut welded on the ends, and the appropriate Heim joints. The piece attached to the lower heim joint attaches to the lower wishbone on the front suspension.

Installed on the car

Timing marks

Doing proper ignition timing has always been an issue because the plate with the timing marks appeared to be missing. But while I was replacing the oil pan gasket, I found the plate at the very bottom of the engine, where it is doing me no good at all.

Here is the plate all by itself and it has slotted holes so it may or may not be accurate

I used a dial indicator on cylinder #1 to find true top dead centre

Then bent a piece of hanger wire and bolted it to the water pump housing. Then cut a notch into the pulley and marked it with white paint. Now I can get out the timing light and properly time the engine.

Leaky coolant sensor fix

During the first big race, a coolant sensor on the water pump sprung a big leak. I pulled it off and discovered that somebody had tried to fix it with silicone and safety wire.

I removed the sensor and was left with a nice flat area for bolting a plate

I drilled and tapped 3 holes

Then bolted on an aluminum block off plate

First Autocross

Well, I think the Pink Panther performed better than expected. The handling is awesome although the amount of engine braking when you chop the throttle is startling, the rear tires just stop moving as quick as the car. I didnt find the unassisted steering difficult but Briget did. The power was way down and we think it is fuel pressure related. The regulator would not hold a steady 3 psi, it would fluctuate between 0 and 7 psi. Then it developed a previously unknown coolant and oil leak and that's why we only did two runs each. Another weird thing was after a couple of runs, the engine would stall when we hit the brakes, even with the clutch pushed in. Perhaps related to the fuel pressure problem. But , as I said, it handles far, far better than expected so it's going to be awesome when I sort the engine out. Here is the video:  http://www.youtube.com/watch?v=_g1JsBUA32o