Alright, so it's a given that cold air and a cool block=more power. Well, last two days, with it being below freezing tonight and last night and being in the 30's and 40's most of both days (coldest 2 days since last winter here and coldest since I purchased my G), I've noticed a very noticable jump in performance, both immediate (including the cold start, where it is louder and the RPM's go a little higher before settling) and over time (the cold air seems to be getting to the engine better and seems to maybe be keeping the plenum a little cooler) keeps alot of that power instead of dipping off after the first several minutes. I drove it for a half an hour and noticed that after 30 minutes, it still drove strong like I had just started it up, unlike the way I was use to whereas after those first few minutes, the heat seemed to be taking a noticable toll on the feel/power of the car.

Now, granted, the same was true w/ my old Accord, but not to this extend.

 

Air intake temperature and coolant temperature significantly affect the G35's engine performance.

 

heh, I've definately found that out.

 

yup so have some fun an rip on it while it cold

 

1% air density increase for each 11F drop in temeprature. 75F drop is like adding a 1.0 psi supercharger plus
Gasoline has a knock index that changes with air temperature [the combustion temperature].

Ignition advance is reduced in warm weather to avoid knock so ecu adds some back as the fuel gets colder.

Winter gasoline tends to have a higher BTU [by product of being more volatile to meet Reid Vapor index] and thus creates higher BMEP [more torque]

 

My G35 went from upper 14.4s in upper 70 degree weather to lower 14.3s in lower 50 degree weather. No changes to the car. Over the past 7 years, my experience been that the VQ series motors tend to run about .3-.5 seconds and 2-3mph faster in 40-50 degree weather vs 80-90 degree weather.

 

love it when it starts to get cooler, car craves it

 

So I’ve been having a problem with trying to drift my 03 g35 coupe, in the hot weather I can barely get it to kick out when clutch kicking and if I get it to get sideways, it will lose power and straighten back up. No matter what I do to try and get it sideways. I’ve replaced all the crank and camshaft sensors. I do have a knock sensor low circuit code. And I’m sure it’s the sub harness that needs replacing. But other than that I don’t really understand what could be causing my issue. Literally today it’s 30 something degrees, took it to a boat ramp and she ate like nothing was wrong, cloud of smoke, and was able to hold the drift as long as there was pavement. Could it be the cooling system not keeping the engine cold enough and it’s getting too hot, or something with the intake? Just confused. Any help would be much much appreciated

 

Seems like you answered your question. Have you put a switch in to disconnect the yaw switch too?

 

yes i have both abs and yaw sensor disconnected. Ive been getting the same response lol I just wanted to be sure because if it was the knock sensor sub harness I figured it wouldn’t matter what time of year, if I tried to drift it wouldn’t let me with the power loss. That’s why I was stumped.

 

“Correlation does not imply causation” is what I think of here, ha. Probably unrelated to weather, those harnesses are cheap replace. Cheap insurance.