Basal Skull

Another great weekend a the Ridge. Problem for me was the tires (nt01) I had ordered in showed up with damaged beads and replacement set was a week away. So went to the track with my 5+ year old street tires, driving pretty slow. Kind of frustrating. Confirmed that my friends in newer cars are much faster with me on old street tires...

anyhoo, did some off roading in an unusual area, coming on to the front straight - too much power, not enough tire . Incredible amount of dust, couldn't see anything, don't know how many times I went around as I couldn't see anything with the dust. Car stalls, I hear someone yelling to get the car out of the grass as there's a fire, well the car's stalled. So jumped out with the fire extinguisher - now occasionally, you see guys come out of their cars in a hurry with their helmet off but still stuck to their neck restraint as you sort of forget to release the neck restraint, I did the same thing, had the helmet hanging off the neck restraint but got the fire out. Car seemed okay and drove back to paddock.

Could have been much much worse, was able to drive the next day with only minor off at the end of the day virtually in the same place
(Apologies to the other drivers and RS driver behind me who had to swerve to avoid me yesterday )

I'm making sure I have a spare set of track tires available at all times from now on, not going to the track on street tires except in the rain. The plasti dip seemed to protect the bumper from the heat. Also need to recharge the fire extinguisher, don't go to the track without one.

Targa Tim

you were much slower in street tires, probably 6 - 8 seconds per lap off your usual.

good for me, as I enjoyed your point-by.

Basal Skull

Always good listening to your exhaust and admiring your back side, don't get to do so very often

Mike J

Close call - great you had the right tools at hand, or it could have been much worse - Porsche BBQ is expensive! Have you had a chance to look underneath to see if no damage to some of the plastic bits (valve covers) ?

The track area must be getting really dry - any chance they would shut down due to fire concerns?

Cheers,

Mike

Basal Skull

Yeah Mike close call...

The other things I had to do while at the track after the off is take both rear wheels off and deflate, remove all rocks/debris that had jammed in between the tire and rim, also had to take the rear brake caliber off one side to get rocks out between the caliber and brake disk. Re-inflated tires and checked next morning to confirm maintaining pressures.

I had a good look underneath today on the lift, cleaned/hosed it down from underneath, took the trans cover off. Looks fine: plug leads, O2 sensor wires, valve covers, turbo oil and actuator hoses, driver shaft covers, and heater hoses (I don't have any rubber suspension components). Parts of the orange heater hose looks a little toasty but that's about it. Changing oil and trans fluids, greasing/oiling all suspension components and cleaning up the interior over the next few weeks/week ends; and getting new tires! Not sure I can make any more days in June/July but will try to go to a couple Fri/Sat week ends in Aug/early Sep.

Al Pettee

Agree 100% on the fire extinguisher, even if you don't race.

A few summers ago at Watkins Glen, I finished a 30 minute HPDE session, and pulled into the paddock, and when I was idling and cooling down, flames suddenly shot up from the engine bay, so I jumped out with my fire extinguisher and snuffed out the flames before anything else got burned. Turns out it was Pentosin leaking onto the hot exhaust from a corroded elbow joint from one of the lines. Talk about Code Brown....

Basal Skull

Can't have too much safety equipment

That high pressure Pentosin line ... one of the few fail items on these cars, especially if run hard. (mine failed and left my car stranded on the track for a week a few years ago, and the only other local 993 turbo that was frequently tracked had bad lead on track - I've deleted mine as most of you know!)

Mike J

Wow, that is a replay I had a few weeks ago on a DE event by the Vancouver Island Porsche Club - just finished two days of pushing the car - got the checkered for a cool down lap, was about 1/4 the way around and blue smoke starts to pour out of the rear of the car. I stopped and assessed - I was the last guy on the track so it was closed - and saw a light fluid dripping out. I took a chance (stupid!!) and got permission to drive backwards on the closed track to the pits.

After getting back to the pits and spending a bunch of time digging in, I found the soldered seam between the banjo head and the hard pressure line for the clutch assist failed right at the pump - spraying high pressure pentosin onto the right side of the engine and it was dripping down onto the heat exchangers. VERY lucky no fire.

No fixing that kind of leak in the field nor would I drive with the pump dry, so removed the IC/air box/bottom cold air lines to the turbo and a bunch of other stuff to get to the P/S belt which I cut and drove home using "Armstrong" steering - damn car is really heavy without assist, plus 2+ hours on my back under the car.

I replaced the line but will need to replumb so that side of the pump just moves fluid directly back to the tank rather than hold unused pressure. I think the primary reason it failed is someone before me had mucked around there and not put the strain release back onto the pump properly, so the stress went directly into the banjo fitting.

Cheers

Mike

Basal Skull

I was thinking re: the Pentosin line (it might be something similar to the reason the RS alternator pulley is designed to spin the alternator slower) - when running at sustained higher rpms, the pump just spins faster/produces too much pressures (also the vibrations like you say and that strain release thing not working well).

Basal Skull

Good idea about cutting the drive belt btw, wish I had thought of that when mine failed (although a pain to get at), I would have been able to drive home. Could you use the clutch okay without the assist or had you done the manual clutch thing already?

Mike J

Put in a new RS clutch with a GT3 disk/motorsports PP earlier this year, and did the conversion. Initially used the MPL, but found out the downside of an increased diameter slave is the stroke is shorter, and on a brand new clutch, the engagement point was basically on the floor. It was drivable but when cold, the transmission was way too balky, and it required long strokes of the clutch pedal. I went back to a stock slave cylinder until the clutch gets compacted a bit, then I will be back to the MPL. With the stock NA slave the engagement point is still quite low, but at least its off the floor!

My understanding is the clutch circuit pressure regulator (it's just above the pentosin tank in the engine bay) regulates the pressure out to the clutch assist at 70 bar, and bleeds any extra pressure back to the tank. I had a line made up that basically took that regulator out of the circuit, and allowed the pump just to pump the fluid back to the tank - but it was too tight of a fit to make it work well in the long run so I will need to work on it again later this year.

Honestly, I am not sure if the failure was a true mechanical failure or due to long stretches of higher RPM's, not sure, it could even be both. On my car though, it was clear the strain release was not attached well, so I fixed that.

Cheers,

Mike

Essexmetal

We have had three failures here of the power steering hard line. Crack started at the end of the weld bead of the mount tab. Two were leaks, and one was a pretty good fire. As luck would have it, it was my car that produced the burn. It was on the track when the right turbo decided it did not like to be oil cooled. I knew it was the powersteering and made the conscious choice to drive it up the hill into the pits rather than stop at the corner worker with the dry chem extinguisher. By the time I got there most of it burned out and what was going was the engine compartment seal which got put out with two bottles of water. Not hard to convert to high pressure Aeroquip and suggest that anyone who still runs the stock line seriously consider that upgrade.

Ryojo, glad the effects were minor !!!!!

Mike, I take it the VIRPCA was running on the mainland ? This weekend we had Ross Bentley as a guest driver coach at our event. He mentioned there are building a world class track on the Island up by Cowichan. Spending my first 28 years on the Rock it will be interesting to hear what is happening with the track and any updates on its completion.

Rick

Mike J

Hi Rick,

Excellent advice re: getting proper lines put in!

This particular event was sort-of a track event, the Vancouver Island Porsche club holds the event in Ucluelet - they take over two full runways at the Tofino airport and run a very large Auto-x one day, and a higher speed DE event the next. Its can be fairly quick (around 220KPH in the back straight) but it's not as good as a proper track , no elevation change- plus the runways are a bit brutal on tires/cars given they are mostly concrete and have been exposed to the west coast weather for decades.

The autocross if more fun in many ways, 500+ cones and 1.5+KM's long - that is a bit of fun, a lot more than your standard parking lot event. There is a bit of sliding as well given some sandy bits ...

I had heard about this new track, it will be great to see it in action.

Cheers,

Mike

OverBoosted28

Do you think new lines will last at least for a while, on a car that's tracked about a half dozen times a year? I replaced my lines that were starting to seep. Would really hate to have one of these go at the track. I don't trailer it, so I need it to last.
Maybe someone can share a DIY on beefing up these lines/system for those of us that still have our assisted systems.

Essexmetal

Boosted, I would say that the split at the support tab is 100% a fatigue issue. Newer lines would have to be a better choice for added longevity. RPM may add to the shake but it may be just a time running thing and being exposed to track conditions does not accelerate the problem as much as mileage. The other two failures on turbos here were street related, those car never saw the track. Hydraulic pumps create a lot of pressure pulses that can fatigue things quite quickly.

An aged memory does not allow me to specifically tell you what the adapter fittings were that I used to connect the pump to the distribution block. The metric to AN hose fittings can be purchased from BAT... British American Transfer or Pegasus Racing and many other places I don't use. The line is a dash 4 Teflon stainless steel Aeroquip. Same type as popular with brake flex lines, except those are traditionally dash 3 size.

There is more work in getting the **** out of the way for access than installing the line and adapters. Mine has been trouble free for 5 years and almost all on the track. Certainly there is less of a worry on the street since the temps are down and it will be a leak not a fire.
Rick