1 line over 220, and it is 100° f outside..... I have had my car coming up on the 260° f line when it was sub 50° s outside so you ain't even close. But at 100° f ambient outside it wouldn't take long to get to the 260° f line fast.

So you where about 240, Invest in a oil cooler, He wont get UPREV( Long story) so the fan mod is out, But both very well worth it, I saw nothing over 185 last week in the 100-103 heat. I have both oil cooler and the UPREV fan mod. :)

just relax......... it is happen when cars heatsoak

TIP; make sure the front of your radiator is clean and not full of bugs.last night i was taking the fang vents out and noticed my radiator was pretty much covered in bugs.so as soon as i was done with the fang vents,i took it to a car wash and sprayed the rad off with a pressure washer keeping adequate distance from the fins to avoid damage.

today is 87 here and after the car was fully warmed then sat for 15 minutes.i took it for a good hard spirited drive on the back roads going to redline a couple of times and then maintained shift points from 4-5k.surprisingly my oil temp did not go past 207 which before this it would get to 220 pretty quickly.so fang vents removed,clean radiator is working pretty good. :happydance:

Yesterday here it was 107 here in DFW....ughhh I drove the Z to work and midway through my commute it felt much more guttless (oil temp never rose above 200) when I punched it to get on the freeway, later that eve I drove the Max to Nordstrom. After a while it felt guttless to, Vq's just hate heat.


An old article from Oct 09 R/T Observed:

An observation we made over the week was the VQ's sensitivity to temperature. Engines prefer cool weather, but the VQ absolutely detests hot days.

when the oil hit 220 the car start to lag. anyone know how to fix it?

Man, my car sits at 220F on the regular and i dont notice any slow downs from it... Lucky me:tup:

This lack of power is not from the hotter oil temperature, it is from the hotter ambient air temperature. Warm air is less dense, so it makes less power. This is why cooler air makes your car run better. Think of an intercooler for FI.

True, but I really doubt it's going to affect your emissions/inspection. Even California won't trip on that afaik.

Anything's possible ;)

A relay, some wire, toggle switch, and maybe some diodes should get the job done. Just run a 12V wire to a switch, and have the relay trigger the fan(s). I haven't looked at how the fans are controlled on the Z34 so you may need to use some diodes to prevent confusing the BCM or something. I haven't done much hacking on a CAN Bus car.

^ it works when the engine is off but as soon as i start the car,the ecu takes over regardless of the simple switch.if you do find out how to be able to do it with the engine on,id be happy to make a small donation to your favorite charity lol. :)

The AC does help with oil temps, I'm not sure what's up exactly but it is 100% observed since I've got my car, regardless of driving style, AC on = cooler oil temps.

I've not added an oil cooler yet to the stock Nissan water-to-oil one.

Would be interesting to note how much power is actually lost while keeping AC on, maybe around 5 to 10 hp max, I really don't feel much (maybe would on the track though... when I go at some point, only just over 560 miles on mine)

Last week temps were so hot that my oil temps almost touch 240F. I don't think it's pulling timing, but more like limiting throttle. I can feel the car accelerating and hitting a wall as if throttle opening was limited. Physically flooring it has no effect. It's a weird feeling, but I "wstar" made a good point about the ECU limiting throttle opening at low revs. This is one really hot summer.

Yes, on a stock ECU, turning on the AC will keep oil/water temps a bit lower in the heat. It's because the stock ECU turns on the electric radiator fan(s) at lower temps when the AC is on than when it's off. UpRev can set them to turn on whenever you want regardless of AC :)

I'm surprised some of you guys are having issues with oil temp,the past 4-5 day in Atlanta has been 95+ and 3 of those days were over 103deg and my oil temps haven't gotten past 210.

The throttle limits wouldn't be directly related to heat though, that's just a general thing. This engine does pull timing when things get hot. The ECU is very dynamic about timing. It's looking at very sensitive knock-sensor data and basically always keeping itself just under the threshold of hard knock. So you can think of it as pulling timing in the heat, or adding lots of useful advance when things are cold, but either way it's trying to safely make the most of the available conditions given air temp/pressure, fuel octane, etc.

yeah, I've been noticing that lately as well. It has been over 100 degrees lately in MN and I have no lower end power. However, when it hits 3.5k rpm or so, there is a burst of power.

Thanks for the clarification, wstar. How does this affect your updated throttle tables? I really hate the feeling of not being able to open up the throttle more than anticipated under 2k and even worse when hot.

Its been in the 100's here in central Texas as well. I can really feel power loss in these conditions. I was thinking about getting a vented hood to try and let some of that heat escape from the engine bay.

Man, I can't wait to get back home to WA state next year!!!! If it gets in the high 80's during the summer, thats considered a hot day for us, lol.

That's nothing I have a shot on my phone last week of 115deg.

You guys must have a special car or special sensitive butt dyno. I ran my car around the track at 190F (first lap), to 260F near the end of the session (18 min later), it had virtually no change in acceleration performance as verified by top speed/long g's.

It doesn't affect throttle tables in any real way. Heat is heat, engines don't like hot air.

It's really about the hot air, not about the hot engine oil. If your intake air was relatively consistent, the oil temp isn't going to affect things too hugely (other than perhaps some minor effects from hotter coolant/block heating your intake air a bit on the way in). No engine likes breathing hot air, because there's less oxygen per volume to use. Hotter air is effectively the same thing as restricting intake volume and/or flow rate (think NASCAR restrictor plates).

could you please elaborate on this? Are you talking about emissions inspections? And if yes, what does an uprev tune have to do with emissions?