Trackday Troubles - Blown Intercooler Hose

I was lucky enough to attend the Macquarie Racing trackday at Wakefield park, was a fantastic day. I had planned to shake down the car after the clutch install and with the previous overheating issues that I had experienced.

The first session the temps were around 24deg with little to no wind, the car performed well with temps very stable after 8 laps at around 1:04 second mark. It was just me and two other cars out of the track, I came back in to check on things and the tyre pressures.

The second session I wanted to continue to check the car and if all was OK I would duck out at lunch time and put on the 3 spare tyres I have had sitting around for about 5years, not the best to set times on but with the rears now without tread I needed to change them over. Unfortunately about the 3^rd lap in the intercooler hose blew, trying all of the shops in Goulburn I was not able to get a replacement 2in to 3in 90deg elbow silicone joiner.

Driver & Isolation decals

Apex racing delivered a Isolation decal, also picked up a driver name decal and race numbers for the door to replace the old magnetic numbers.

6point Harness and New Velo seat

I had purchased a new seat for the car back a number of years ago whilst at WTA and never got around to actually fitting it, has been sitting in the garage ever since and thought it was time to fit it to the car and at the same time replace my current Willans 4point harness which is very old and I am finding that I am submarining in the seat when driving around the track.

I picked up a new harness which is a sabelt 6point harness from V-Sport yesterday to fix the submarining issue, the added bonus of this harness will be that it will allow me to use a Hans device in the future when funds permit.

The crotch strap on the Sabelt harness is fitted over the hoop that was installed under the seat originally when the cage was installed, it is then attached to two eyelets with a square place underneath towards the back of the seat on the floor. When fitting the eyelets I miss judged the holes and ended up drilling into the chassis frame so had to drill another hole which was disappointing.

When it came time to then fit the new seat I could not actually get it into the car with the Bride rail attached to it so had to remove the seat rail to get it through the door and cage into position. One the seat was in position and the rail mounted to the vehicle when I tried to fit the seat to the rail the seats side head protection fouled on the roll cage.

I will need to get some custom mounts made up to install the seat lower in the car so that I can fit the seat in without fouling on the cage.

Lithiumax battery

I picked up a new Lithium battery today from Lithiumax. 450cca and weights 2kg, comes with a nice little trickle charger and a fantastic neat mount. Price is reasonable as well at $459.

First test and it works really well with a very strong cranking ability.

ECU heat and vibration reduction

A friend recommended i get some isolation mounts to avoid having issues with the ECU, the theory is that vibration and heat kill ECU's quiet quick so it is ideal to mount them in locations that avoid these areas. 

Using these isolation mounts i can fix the vibrations coming through from the chassis and also it increases the gap between the transmission tunnel and the ecu so improves the heat shielding.

Rear bar removal

The rear bar set up has been worrying me a little as even with the sheet and air stakes i reckon it catches a lot of air down the straight. I removed the rear bar and think i might try and run the car without it next time with the aim of lessening drag.

Lithium battery

After sitting at the workshop for a couple of weeks and then trying to start the previous battery i had been using died, i tried to charge it back up but it started to get really hot and would not fully charge. I think it might have lost a cell.

I purchased a new lithium battery recently after talking with a couple of the guys and it arrived very quickly, it was only 0.8kg so super lightweight. Unfortunately after installing i found it was simply too small for my vehicle as it would not start it without adding in an additional jump start battery.

The Lithium battery i thought was 12ah which was close to what i was using before but found it was actually 4ah, also the CCA was 195 and it probably needs closer to 400 to start the car

Remember to tighten those wheel nuts

After picking up the car from ASR this morning who sorted the clutch install and machining of the input shaft for the clutch. I got 5min down the road and saw the trailer wheel bouncing off into the bushes, cars swerving to miss it.
Andrew brought up some wheel studs for me which was nice bit ended that the studs were stripped and that I needed to get new studs. NRMA came out and the nice guy offered to go down the road to get some new studs which we promptly installed and in was on my way.

Towing Weight Check - Race Car & Trailer

For those towing with there cars it pays to check things out. Got mine weighted today and with nothing in the car (I usually have a lot of tools etc) and nothing in the cruiser but a full tank it was the following.  Remembering that my trailer is 2000kg max total weight
On Ball Weight

• 1820kg trailer (ATM)
• 3200kg car (GVM)

Off Ball Weight

• 1990kg Trailer (ATM)
• 3030kg Car (GVM)
• 5020kg Total (GCM)
• Ball weight 170kg

Leaves 10kg to play with on the trailer (not sure if I even have a full tank in the Nissan)

Trailer tyre issues

Found an issue with clearance on the trailer of the rear tyres.
The center guard has a support and it is very close to the rear tyres, it seems to have started to rub causing a section of the tyre and be worn down.

I need to cut it off and then weld it back on to fix it.

Understanding the possible reason for the clutch failure

Andrew from ASR picked up on an issue today that was missed in the previous install and most likely would have been the cause of the clutch failure.
Using a flat ruler he checked the flatness of the clutch discs and found them to be bent out in the center, this was very odd and along with the failure of the retaining plates, which he had never seen before just didn't seem right.

In the installation instructions it shows that 4mm must be taken off the center shaft otherwise it can cause a failure.

Checking with another box he was able to confirm that that 4mm was not taken off the input shaft which meant the center bearing was pushing too far into the center of the clutch and bowing out the clutch discs eventually causing the retaining plates failure.

Trailer tie downs

After a recent trip to Wakefield, driving back the rear tow down had come loose and the car was only secured by the two front tie downs.

When I got home and realized I could see that the car had moved back about 30 cm and onto where I had secured the splitter using the remaining strapping from the now loose tie down. Had I hit the brakes hard there was nothing stopping it from moving forward.

I have been using the following method for some time which is, two tie downs off reinforced front tie down points on the car to custom eye bolts on the draw bar. One one strap across and through the rear diff cradle. 

This method  has worked well up until now, with 11h trips to Phillip Island and having minimal issues, I think a mix of tiredness and not tightening the straps correctly have caused the issue. Time for a rethink.

I have been looking online at a number of different options and methods and came across one that uses the existing 50mm wide tie downs and a short strap that they go through, this then forms a loop that goes over the wheel and is tied down at an angle to the sides of the trailer.

A lot suggested only two were required but I wanted to be sure so have gone with 4.

First attempt and it seems to secure things well although there is some slight movement forward and back which has me worried a little.

Clutch rebuild kit arrived

The replacement clutch has arrived through Otomoto, i ordered it on the 1st October and it has taken a little while longer but i allowed 4 weeks just in case.

Clutch spring retainer broken

So i finally managed to get some free time and motivation to pull the gearbox out after the eastern creek track day last month.

Man those top bolts are a pain to get to, i  removed the exhaust and top intercooler piping then got long extensions and got most of them except the top two on the passenger side.

These are always the pain in the arse ones as they get heat from the turbo and exhaust. After stuffing around for ages i managed to get a spanner onto both of them and crack them loose.

I didn't have a rear gearbox/tail shaft piece to stop the oil coming out so i just drained all the oil to stop it coming out. Adding in some extra safety with two straps around the box i managed to get it off and remove the clutch. 

Turns out the spring retainer on the 2nd clutch plate had failed. The intermediate plate and flywheel have coped a bit of abuse as well but not bad for a clutch installed in 2003. Need to get a rebuild kit now and then machine the flywheel and out it all back in but i might get someone to do it as i cant do it myself i think.