Jump to content


  • Content Count

  • Joined

  • Last visited

About Redracn

  • Rank
    Ferry's Protegé

Profile Information

  • Location:
  • Ride/s
    991.2 GT3,997 TurboS, Cayman R

Recent Profile Visitors

1,357 profile views
  1. I haven't been following this thread so I am probably a bit in the dark about what is going on. I did just look at the logging screen shot above and the MAP pressure and had a good giggle as it was a very flat trace which is not what you get with airbox/filter restrictions. You expect to see the MAP pressure drop as the airflow increases. I am concerned that Motec is in trouble as they have not released a new product in over 5Years which is forever in a fast changing hi tech industry and a lot of the products are now old and stale. M1 was designed around 2006 so even it is showing its age. Even the colour dashes are just an ADL3 with a third party plug in graphics processor added to run the colour LCD. "What size throttle bodies?" Or do you mean a single throttle body? Now there's a loaded question. ITB are a tuned resonant part of the system so as usual the answer is that it depends!. Heads, cams, rev range etc. Every bit needs to work with the other bits to give the best result. The best source of this information is from someone who has been there and done that with real data/results to back up their expertise. When it comes to power and dyno results the old saying "the BS stops when the flag drops" about somes it up. My advice is that unless you are just happy to have a bit of a play and the final results are not that important do it right once and go to an expert on your engine. Yes I know there are many so called self proclaimed experts out there and finding a genuine one is near impossible.😟 Now for a TB that feeds a plenum it just needs to be big enough to have minimal pressure drop across it. What pressure drop is acceptable? Well that depends too.. I would expect something around 75mm would give good results on a 3.2 but that depends on what feeds it and what is on the other side. I.e no use being bigger than what follows or precedes it. The less sudden cross section area changes the better for air flow. Now you need some CFD calculations or a good old fashion flow bench to evaluate all aspects of the inlet path. I did a check the other day on my rally cars stock air filter. At full noise it dropped 9KPa. Put in a K&N and the drop was under 1KPa being a Turbo it did not change the end result much but in a NA it is a huge gain. Lesson! Air filters matter especially on a NA engine.
  2. I had an issue with my GT3 PDK where it went into limp mode saying Reverse not available. Turning ignition off and on would not fix it. Factory tech from a Porsche center hook up his laptop and it reported a clutch 1 error so no Rev,1st,3rd,5th,7th gears. Codes were reset and after a so called detailed inspection it was declared all good. Nothing replaced. I am very disappointed that a car with just over 3,000km would have such an issue but what really annoys me is that nothing has been done that would fix the issue. I suspect I am not getting the entire story from the official Porsche Center and until I get a real explanation I am reluctant to take it anywhere as faults never fix themselves. At this cost level you expect any issues to be properly sorted first time whatever it takes as having the customer do the field testing is very poor form. OP. Sounds like the electronic module or possibly a sensor. Absolutely nothing to do with being in sports mode.
  3. Still a big gap. The Yokos are a real race tyre with stiffer sidewalks and warm up way quicker and have a bigger operating range and far better cycle capability than cup2. Z221 are even faster but with a narrower temp range. Dunlop DZ03G are fighting back against Yoko and I will be trying their latest in a few months. Putting R rubber on a road tyre construction just makes a track capable road tyre not a race tyre.
  4. Does your 996.2 rev to 9000rpm? Hydraulic lifters have their place but it is not at 9000rpm and up.
  5. 👍 The accountants would also be consigned to the corner with the marketers. Especially given a repeat of the 991.1 engine debacle would be a real problem for the GT department so the 991.2 engine had to deliver no matter what. It seems the accountants are in control of the 991.1 engine cam DLC coating durability improvement (I won't call it a fix) as it's cheaper to replace the engines as they blow up for 10 years than it is to recall and replace all 991.1 engines with a real fix (more expensive to build engine)
  6. Yep It seems they could not convince the actual race engineers to use the 991.1 engine in 991.1 cup cars as they went with the proven Mezger. Would have been an interesting meeting between marketing wanting the new engine and the engineers saying no way will we use that road oriented unsuitable engine. At least the engineers won that one. 👍
  7. Racing sorts out the weak point very quickly and if Porsche had raced the 991.1 engine they would have sorted its valve train issues before selling to the public. The 991.1 engine has a road car style hydraulic clearance adjusters and crank lubrication. The 991.2 engine uses a better Motorsport style center feed crank lubrication and solid lifters as is the norm in Motorsport style engines. Some will value the direct Motorsport link and some won't but it will reduce the buyer pool for 991.1.
  8. Lower rev limit may help with the cam issue. Otherwise I don't believe the cam gear design is any different other than the later manufacture than GT3 means they have already applied the DLC (Diamond Like Coating) coatings as do current GT3 warranty replacements.
  9. Reasonable effort by these guys and a lot better than most but I would still only give them 50%. Checking the temperature rise is good. The power supply was inadequate. Locating the saturation point is required but it only takes a few seconds to do it once you have the test rig running. For coil on plug applications the battery voltage has little affect unlike what they reported as does the rpm as pretty much any coil on plug can do 20,000+rpm with the limitation being its temperature rise in the given application. But the biggest mistake is the singular focus on energy. There is another very important part to a coils performance especially on boosted applications and they have ignored it. The "Maximum Available Voltage" determines if the spark can jump the spark plug gap under the cylinder pressure. If the available max voltage is not high enough then you have no spark and a misfire usually showing up around peak torque . Also most of the energy that would have gone into the spark is absorbed by the igniter electronics greatly heating it. The spark current is also important and while integrating arc voltage x current gives the energy delivered you need to know the spark duration/current as for the same energy you can have a short duration high current or a low current long duration spark and whiles a longer duration may help a poorly tuned engine idle a bit better a spark that last 10 degrees of crank angle at 6000rpm is of no use because if you have not ignited the fuel in less than 1 degree of crank then you have bigger problems to sort out and a shorter duration higher current spark could be the answer with its higher instantaneous power to ignite the mixture. I would ignore their results as the focus on energy delivered alone is only small part of the story in any well designed ignition system.
  10. Agree about hybrids as being a far better option in Aus. Also agree that for most/some on this forum the cost argument is academic but for the vast majority it matters a lot and for these technologies to make any difference to CO2 emissions and a clean energy future it has be be viable for the masses. By masses I also mean in China, India etc as without them onboard nothing done in Australia will make any difference. We in Aus could stop all emissions tomorrow and China growth will cover that in a month. Sola PV just pushes the cost of storage back onto the grid rather than seeing the bill for your batteries. So far the grid and non solar customers have worn this cost but will that continue? The manufactures are being forced to make EV's by governments. One method of coercion is the banning of ICE from specific areas or markets and the other even worse one is Corporate Average Fleet Consumption in the EU and USA that require a minimum mileage be achieved across the fleet and this number is getting smaller and smaller and smaller (CO2/km). The only currently viable way to use less fossil fuel at the car is go electric and burn that fossil fuel in a power station where it is not counted in the consumption calculations. Hydrogen may also get a look in but most is currently produced from fossil fuels. Lots of people will have to buy electric so we can still get an ICE Porsche sports car. All this because the government is taking more control of our lives. The EU already dictates the energy properties of toasters, kettles, vacuum cleaners and cars.
  11. Advice as to the best power supply heading forward is like financial advice as it depends on your situation, ability to go without and future predictions. As an Electrical Engineer my view is that Electricity costs are only going to go up with more renewables as they need 100% backup and the suppliers of that backup expect a return on their investment so will charge appropriately. Use them less and they will simply charge more. The government has a limit on how much can be charged of $14,2000/MWH which limits their ability to recover cost. Many other additional costs due to renewables but that's another story. One possible scenario. To give your EV a full charge at night you will need a battery of similar size to the one in the EV. So a 75KWH Tesla will require 6 Powerwall II at around 13K each that's $78K and the life expectancy is 10 years so that's $7,800 a year just to own the storage batteries. Now the size of the solar panels and batteries you actually need depends on how much you drive and how many days you need to go without sunshine. It could be both bigger or smaller depending on your ability to handle not having the car available. You could spend an even bigger fortune on batteries and solar panels but there will still be the odd occasion you run out of power. So to cover that you can use the grid or have your own genset. The smaller the solar/battery system the more you will need the grid/genset or go without. A quality 8KVA 1500rpm diesel is over 10K but has a very long life. Current fuel cost for a diesel for domestic electricity use 1.1L for 4KWH @ 85cL or about 23cents/KWH for fuel cost plus asset cost and maintenance. Currently that $7800/year will buy 5,600 L of diesel at $1.40/L my V8 diesel Touareg would do 66,000klm on that much fuel and many smaller diesels could nearly double that. And that is just the cost of owning the batteries and not the panels etc. That 8KVA genset on $7,800 worth of diesel @85cL is 9200L or 33.4MWH I use 18KWH/day = 6.6MWH/year so $7800 would run my house for 5 years Batteries in the power supply make no sense except in the outback and even then the biggest benefit is not having to listen to the generator at night and having some power overnight when consumption is lower and running the generator is less efficient.
  12. It seems that fuel cost is a common reason to look at an EV. If EV become more common the fuel cost will rise to match or even exceed fossil cost as the Governments will need to replace lost revenue and given they will have full control of your supply at state level will most certainly charge significantly more if you want to charge at peak times, at night or on low wind days. The faster you charge the more you will pay as well. Rationing is already here renamed as "load demand" and we can expect a lot more "rationing" in our future even without an EV rollout so buckle up this will be a wild ride.
  13. I would go a bit higher being a 997.2 with PDK. At retail it would be 180-190k so at auction I would go to 140-150K
  14. Thanks for the laugh 😂. Don't let reality get in the way as feelings are way more important👹

PFA [Porsche Forum Australia]

This is an online platform for like-minded Porsche fans/fanatics/tragics to come together to read, chat and share.

It is also a platform to arrange and participate in off-line social meet-ups, events and drives.

  • Create New...