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car is losing power, when it's hot after spirited driving...

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Old 07-13-2011 | 03:05 PM
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From: NoVA
clear case of heatsoaking
Old 07-13-2011 | 03:09 PM
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What's the ambient temps where you are located?

When it gets to 50-55C here you can definitely feel the loss in power, and the coolant temp will rise to about 95-100C, that's without major spirited driving lol
Old 07-13-2011 | 03:26 PM
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Originally Posted by MACS
FYI - Loose is the opposite of tight, lose is the opposite of win.

+10 Points for knowing what grammar is!
Old 07-13-2011 | 03:29 PM
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I've had maybe something of a similar issue from what you described, but mostly in terms of the softer sound. When I had my FI HFC's on and would drive around on a hot day, then let the car cool off while running to the mall or what not, and getting back into it, the sound would be waaay softer and more gentle. I think it might be the HFCs' reaction to heat that affects the sound. However, I'm not sure about the power loss. But, generally speaking, the hotter the car gets, the worse it performs.
Old 07-13-2011 | 09:33 PM
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Originally Posted by ShyTown91
clear case of heatsoaking
this exactly.

Originally Posted by Soliditude
I've had maybe something of a similar issue from what you described, but mostly in terms of the softer sound. When I had my FI HFC's on and would drive around on a hot day, then let the car cool off while running to the mall or what not, and getting back into it, the sound would be waaay softer and more gentle. I think it might be the HFCs' reaction to heat that affects the sound. However, I'm not sure about the power loss. But, generally speaking, the hotter the car gets, the worse it performs.
again, an issue of the motor being heat soaked. not only that, but if you think about it...the cars intake manifold only takes in a given amount of oxygen at a given rate, at any given time. the the hotter the engine bay gets, the less oxygen density. hence the reason why your car seems to run better, and smoother, on colder days/nights. the exhaust note is probably a by product of the given state. deformation in hfc's (the web) is normal, is it not? it's unlikely that your hfc's are done after just ONE year of use, OP. you're fine.
Old 07-14-2011 | 01:29 AM
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Ambient temperature is not too hot here now (30-35 celsium).

Vented hood is not for me. So is it possible to add some engine oil cooler?

Today I'll try to drill some holes in my custom thick undercover for the ventilation purposes and put it back (I like the "brace effect" of it). And will remove upper engine cover, as one racer advised me.
Old 07-14-2011 | 04:10 AM
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adding ventilation means isn't going to really help; from what i understand. i dunno though...i could be wrong. you would think it would, right (as i did). i still think cold air intakes work best to bring in colder air; again, some have oppositions against the whole idea though.
Old 07-14-2011 | 05:12 AM
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how do you think, can my overheating front brakes (and they overheat really bad - stock small 320x28mm) be one of the reasons that engine overheats and goes to the limp mode?

i'll soon switch to the akebono BBK with the 2-piece DBA5000 rotors, and they shouldn't overheat...
Old 07-16-2011 | 11:50 PM
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Originally Posted by Mike
Borderline limp mode?

The hotter the car gets past the threshold, the more it cuts power...
our cars pull 5 degrees of timing once intake temp is above 95 degrees.

causing hp tq to drop dramatically.

when i was getting uprev tune , car had to sit for 20 mins between pulls.
83 temp when if was getting tuned.

nissan could have just done ones from the factory.

a gtm oil cooler will solve this issue, per tuner.
Old 07-17-2011 | 10:49 AM
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Originally Posted by ShyTown91
clear case of heatsoaking
WOW bout time so one said this, What I was goign to say.. Took like 12 posts?? heat soak will kill your HP.. Cant rally do much unless you drive with the hood open,, LOL Felt it on mine yesterday. Temp here are in the mid 90's and humid.
Old 07-17-2011 | 11:37 AM
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oil cooler & you can drive without heaksoak.

every 370z i know that goes to tracks for autocross has ones.

hence the need for an external cooler.
Old 07-17-2011 | 12:03 PM
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Originally Posted by ShyTown91
clear case of heatsoaking
+1 agreed
Old 07-18-2011 | 03:12 AM
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what cooler would you recommend (but not too expensive)? GTM?
Old 07-18-2011 | 08:13 PM
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Originally Posted by harp00n
what cooler would you recommend (but not too expensive)? Gtm?
+1. I would like to know also
Old 07-21-2011 | 10:17 AM
  #30  
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can anybody confirm, that removing upper engine cover (with the infiniti logo) can help a little this heat problem? i beleive, intake manifold would be better ventilated?

or it just will make the air intakes to overheat more?


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