So you are still hitting 240F with two oil coolers? Maybe its not so bad given the track and ambient temps, but I was expecting significantly lower.

That is definitely odd that you still went into limp mode even though you were below the limit.

Yeah something is up with that limp mode thing. I have hit 270 before without going into limp mode.

Thanks! Doing my best to share what I learn... really appreciate everyone's terrific input!

You have to understand, I push the car really really hard. With my original Stillen setup, I would have seen 280f in these conditions I am 100% sure... Also, remember that Nissan has said that 240 is within the sweet spot of engine oil operating temperatures for this car. Most of my time on the track was 180-220f... 240f was peak. I am going to give this kit my strongest endorsement. This is the kit to get! Robert will soon be providing details. He sent me pics but asked me to hold off until we tested it at the track.... hang tight just a bit

SO, HERE'S THE UPDATE... My post yesterday was after my second track session... During third session, I had an epic battle with a Lotus, then the engine completely shut down on me after going into what I thought was limp mode. I had to coast off the track.... It was not limp mode. One of the O2 sensors on headers had become disconnected and very likely caused the engine shut down. I drove the car to my in-laws after the event. Looked all around the car and when I looked underneath I saw that my O2 sensors that attach to headers had been nearly sheared off the location they mount to on transmission. The bolt had either rattled loose or was sheared when the car bottomed out on my 9 hour drive to Utah from AZ. I'm not surprised, I did some very serious canyon driving. I reattached the sensors with some make-shift parts and drove home from UT to AZ last night. Got a ticket on 93, but that's another story...

Lesson learned... All of us that lower the car need to consider relocating the o2 sensor bracket from the bottom of transmission to sides.

Unfortunately, I had to cut my day short and missed the last 2 runs and the time trials at day's end.... But I should be able to post the video from session 3... Stand by

PS Mike, your buddy Jimbo (with MR2) says 'hi'

limp mode on tranny or diff fluid temps?

This is really starting to piss me off.

Trust me, I was irate yesterday at the track... but it turns out this one is my fault, not Nissan's... read my post above, hope it was clear... The O2 sensors simply came undone... wouldn't have happened if the bracket hadn't scrapped against the road or track or dead animal on the road or whatever

Ah I thought both things happened, both limp and then turned off. Got it.

I should have been more clear... it felt like limp mode... you'll see when I post the video that I lost power several times.... engine finally just shut off... No check engine light for whatever reason... at first I thought it was fuel starvation

Just updated video journal with my third session.... as well as a video of engine cutting out

http://www.the370z.com/track-autocro...tml#post112816

Great video :)

So back on the oil temps thing: I'm still driving on the street mostly (for now anyways, although hopefully I can hit some track stuff later), so obviously I'm not heating up the engine as much as you do on the track. I'm running Stillen's cooler plus a 1-qt spacer on the oil pan from AAM for the moment (which also spaces down the oil pickup, so in theory it's going to help prevent loss of oil pickup on a hard corner too).

Anyways, you have any thoughts on what's "too cold" for hard driving? I'm mostly staying in the 190-220 range now even in aggressive street conditions, but on highway night drives at high speed, my oil temps are sucking down to 175-180 when cruising due to the lower ambient temps and high airflow to the cooler. I'm starting to wonder if that's too cold and the oil would be better off a little hotter in that scenario (not that it matters when I'm actually just cruising, but it might matter when I get back on the gas/revs hard at those temps). Keep in mind we're nearing the peak of TX summer heat, so these temps will probably drop substantially in the winter.

I'm planning to put a thermo plate in on my next oil change anyways, which should at least keep the floor at 180. I'm not even really sure how these plates are specified anyways. Is 180 when the valve starts opening, or when it becomes fully open?

Hey WSTAR... I read about your spacer, nice job. There are plenty of engineers and chemists better qualified to answer your question but my quick input is that yes, especially with thicker oils it is better to have a thermostat and avoid running hard at low temps... and there is probably a reason that most thermostats open at 180f... other than that, not sure exactly what the right number is for our cars and your particular oil... Given that I'm using a lot of cooling and a thicker oil, I'm planning to use a thermostatic switch. Re how they work, my understanding is that they are binary - either open or closed - at a given temp... some may open or close partially

Or if you go with a kit like GTM's (which is what I am using) they provide a thermostatic sandwhich plate which lets the engine take care of anything under 180 then it auto starts circulating after that...

I think its a win win...expecially here on the Northern East Coast when temps get real cold, I dont want to be blowing fittings. But then again I let the car warm up...

I would've expected a mechanical thermostat to not be binary, because it's simpler to build them that way (basically a spring that slowly changes shape with temperature), but I guess they could also use some kind of bent bi-metal strip that would snap one way or the other at a given temp. Oh and I'm running 5W-30 Motul 300V too, so mine isn't quite as thick as yours to begin with.

I believe they use a spring design just like the thermostat for your radiator. It should begin opening at 180 and should be fully open by 195 or so.

(btw, sorry travis for the temporary side-issue technical hijack here) I went ahead and called BAT, who are the US distributors for the Mocal plates, and asked them so I could sort this out for sure. What they told me on the phone was this (for the Mocal thermostatic sandwich plates, who knows about other types/brands):

The passageways that flow to the cooler are always open and unregulated. Separately, there is a bypass passageway that goes straight through to the oil filter. The thermostat slowly closes off the bypass passageway as the temps rise. The temp range for the closing-off action is roughly around 5-10 degrees F, roughly centered on 180. Once the bypass is fully closed off (so roughly around 182-185-ish), all oil flows through the cooler.

On the other side of the temp range (when you're down at anything under 175-178-ish) essentially both paths are wide open, it's just that the bypass is the path of least resistance, so "most" of the oil will take the bypass route. But by leaving the cooler path open with a little flow going through it as well, it helps get the cooler system warmed up too, so it's not a sudden temp-shock transition when you get warmed up and close off the bypass.

He said they sell a model that's set for 200F as well, but that they don't recommend it for car applications, and it's mainly marketed at marine/aviation needs.

good info... the 200f could be used to activate a second cooler in a dual core setup