Engine Thermostat, Low Temperature (begins opening at 160 deg F)

[JFP in PA]

Originally Posted by Dr. Acula

Good info to know, thanks! Along those same lines, then, do you have an opinion on the third radiator kit for the non-PDK 9A1 cars?

I have a 2011 Boxster S and I monitor the coolant temp with an OBD-2 Ultragauge. The coolant temps in this car vary as much as 20 degrees just driving around town, It freaks me out because my Toyotas don't vary near that much.

Because the third radiator adds considerable volume to the cooling system, it tends to dampen thermal swings. Things still change, just not as quickly.

[mikefocke]

JFP if the low temp thermostat is so good, why would Porsche have specified a higher temp one? Was it based on predicted use patterns for the "not a race car" Boxster as opposed to the GT cars where racing was predicted? How does the low temp affect emissions? Is there any dumping of more unburned gas (think choke here) into the cats as the "choke" system stays on longer?

[JFP in PA]

Originally Posted by mikefocke

JFP if the low temp thermostat is so good, why would Porsche have specified a higher temp one? Was it based on predicted use patterns for the "not a race car" Boxster as opposed to the GT cars where racing was predicted? How does the low temp affect emissions? Is there any dumping of more unburned gas (think choke here) into the cats as the "choke" system stays on longer?

It was done strictly for emissions purposes.

We have put emissions exhaust "sniffers" into cars before and after the 160 stat install, and actually found slightly lower emissions at idle with the 160 F stat, which ties in with the better gas mileage claims by owners. We did not run the car for prolonged periods at varying RPM's, so I have no data beyond our simple test.

We have customers that have run one of these stats in daily drivers for over 100K miles, and their cats are still fine. Interestingly, we see more correlation between cat failures (read non mechanical cat damage) and running cheap gas, those that always buy the cheapest they can find seem to have more problems than those that stay with major brands of fuel; and this correlation also seems to apply to non Porsche brand cars as well, so I would tend to point at fuel quality as the major determinant for cat failures we see.

[PaulE]

Originally Posted by mikefocke

JFP if the low temp thermostat is so good, why would Porsche have specified a higher temp one? Was it based on predicted use patterns for the "not a race car" Boxster as opposed to the GT cars where racing was predicted? How does the low temp affect emissions? Is there any dumping of more unburned gas (think choke here) into the cats as the "choke" system stays on longer?

You guys are way more informed than me and I appreciate all the good stuff I learn here. I love my Boxster but can no longer wonder why Porsche makes some or the choices they do like -

• use a sealed, greased, ball bearing on the IMS which is submerged in the sump. The use of a common casting for both cylinder heads required the IMS, but at what point did someone say, "Hey, how should we put a bearing on this end of the IMS?"
  
• use a grade of plastic on internal headlight lenses that will turn dark with burn marks even if you only ever use stock halogen light bulbs.
  
• use soft-touch black paint on interior trim panels that turns sticky with age.
  
• design and specify a water pump that should be replaced at intervals to prevent engine damage from broken impeller bits migrating to cylinder heads and causing hotspots.

Signed, glad I don't own a GT2, GT 3 or Turbo requiring me to have my cooling system fitting welded to my engine block!

[JFP in PA]

Originally Posted by PaulE

You guys are way more informed than me and I appreciate all the good stuff I learn here. I love my Boxster but can no longer wonder why Porsche makes some or the choices they do like -

• use a sealed, greased, ball bearing on the IMS which is submerged in the sump. The use of a common casting for both cylinder heads required the IMS, but at what point did someone say, "Hey, how should we put a bearing on this end of the IMS?"
  
• use a grade of plastic on internal headlight lenses that will turn dark with burn marks even if you only ever use stock halogen light bulbs.
  
• use soft-touch black paint on interior trim panels that turns sticky with age.
  
• design and specify a water pump that should be replaced at intervals to prevent engine damage from broken impeller bits migrating to cylinder heads and causing hotspots.

Signed, glad I don't own a GT2, GT 3 or Turbo requiring me to have my cooling system fitting welded to my engine block!

If it makes you feel any better, other high end brands like Ferrari also have similar issues, but only after you spend a quarter of a million dollars to get one........

[PaulE]

Originally Posted by JFP in PA

If it makes you feel any better, other high end brands like Ferrari also have similar issues, but only after you spend a quarter of a million dollars to get one........

I hear you. Having grown up around old English Jaguars, Austin-Healeys, MGs and Triumphs, I thought the days of leaking rear main seals were over! On some of those cars, part of the rear main seal was literally a piece of rope!

Anyway, with guys like you to fix them, LN Engineering and Flat Six Innovations to come up with better IMSBs, Nine8Six to get us better headlights and Ben006 to give us an economical short shifter, it's all good!

Sometimes I think I want to get a newer Cayman S, then I think about what I'll learn about that the aftermarket has come up with fixes for those cars!

[JFP in PA]

There is an old racing adage: "Speed cost money, how fast do you want to go?" These cars are no different; the more you expect from them, the more you have to put into them. The big issue is too many people do not go into the owning experience with their eyes open, and expect a performance vehicle to have about as much maintenance and ownership costs as a Honda or Toyota. Unfortunately, life does not work that way..........

[PaulE]

Originally Posted by JFP in PA

There is an old racing adage: "Speed cost money, how fast do you want to go?" These cars are no different; the more you expect from them, the more you have to put into them. The big issue is too many people do not go into the owning experience with their eyes open, and expect a performance vehicle to have about as much maintenance and ownership costs as a Honda or Toyota. Unfortunately, life does not work that way..........

Totally agree, and the only replacement for cubic inches is cubic money!

Originally Posted by Gelbster

Paul, I share your anxious thoughts about newer Caymans and other 9A1 cars. And then my wiser half mentions Toyota/Lexus, Sad when diy enthusiast like Ben have to fix the basic engineering issues for pennies if done at the Factory. But hats off to those who have relentlessly worked to fix the flaws in the M96 - if only Stelan's AOS had worked better.

Funny, I have my eye on a Lexus RC 350F AWD as a daily driver to replace my Acura TL

[Gelbster]

Paul, I share your anxious thoughts about newer Caymans and other 9A1 cars. And then my wiser half mentions Toyota/Lexus, Sad when diy enthusiast like Ben have to fix the basic engineering issues for pennies if done at the Factory. But hats off to those who have relentlessly worked to fix the flaws in the M96 - if only Stelan's AOS had worked better.

[Gelbster]

RC 350F =Me too.
What would change that is if I could find a really competent,honest and affordable Indie+ suitable car. My Boxster experience has been appallingly expensive and time consuming beyond imagination. And that coming from A Jaguar/Rover/Aston guy !