Carpokes Porsche Forum

Pretty confident my dash gauge reads correctly as I ran the 16V engine with a then new pressure sender which gave excessively high readings and things went back to normal when fitting the 30 year old sender from my 2.5 engine.

The 3.0 bar I see on the gauge at idle is also with an oil temp of around 100°C with the engine sitting still, regardless of the fans running or not.

Seems to me there could be too much main bearing clearance in your block and that would make sense with too little oil pressure at idle thus too little as well in the chain tensioner... I hope I'm wrong!

I'd try the thickest oil you could source as the easiest test before digging deeper.

Main bearing clearances were well and truly on the low side with plastigauge , we ended up measuring everything with a micrometre to be sure.

From the 16v peanut gallery, I'd just point out that my 8v oil pressure at idle is highly dependent on idle rpm (and oil temp obviously). When I was idling at 800 rpm (due to F9 DME quirk) it would run down near 2 bar when really hot. After correcting that and bumping idle to 880, it never dips below 3. That almost 2 psi per 100rpm of idle speed...

Yep it's a hard one, if anything my idle is a bit high around 900rpm. Oil pressure is strong through the rev range and meets the specs in the manual for idle, it just seems to drop off at 100degC.

We spent a lot of time checking the clearances on the main bearing because at first they looked too tight rather than loose, I'll have to dig through my paper work but they were on the lower end of the range.

I guess the most obvious thing to check first for low oil pressure is the pickup, not really sure what else it could be

On my standalone I set a minimum oil pressure of 2 bar with an engine cutoff if it dropped below that. I started to do some spirited pulls in second and third gears. A few times the engine would stall after the pulls at red lights. I was still working on my idle tune so I thought the tune was causing the engine to stall. Long story short, seems when the oil heated up during the pulls and idle still needing tweaking the RPMs would drop causing the oil pressure to drop, it would drop below 2 bar and shut the engine down.

No idea if it’s relevant here or not, thought I’d mention it. Engine is healthy as far as I can tell so not really worried about it. I lowered the minimum to 1 bar at low RPMs.

Could you take a video of the sound for us?

Will do, its a bit hard to start the car in the evening during the week, my neighbours are so close it shakes their windows .

Was planning to try a couple things on the weekend when I can get it up to temp.

Bergerac wrote: Mon May 25, 2026 7:16 pm Will do, its a bit hard to start the car in the evening during the week, my neighbours are so close it shakes their windows. <SNIP>

The Fabspeed exhuast is really loud at idle with no cat for some reason, I need to find a good silencer

When you mention a temperature of 100°C at warm idle, where is it measured?

I really like my Australian-made Varex muffler with a built-in valve...