Hi all

Right, I haven't owned my Sunny GTI-R for all that long but have
begun to notice a couple of things about it, and was wondering if
anyone else experiences the same kind of thing or could offer an
explanation. After stop start driving, after a while the performance
seems to become markedly reduced, and at times it feels hesitant
particularly just before the boost comes in. Is this a problem or just
the way it is. I was thinking that maybe in stop start situations the
intercooler becomes heat soaked, due to the lack of air flowing through
the bonnet, causing the intake temp to rise and therefore performance
to suffer. Has anyone done anything to combat this i.e. fans, water

injection, or maybe switched the intercooler for a charge cooler?

I was talking to Pat the other night about the turbo "kit" in
his car.  He said that on hot days, the knock sensor starts
going nuts and starts retarding the timing and dumping fuel
to keep the motor from grenading.  Sounds like this is what
is happening to you.  Intercooler isn't cooling the charge
enough (or is getting heat soaked) and the engines is trying
to protect itself the only way it knows how.  I do remember
seeing some cars that mist water onto the intercooler during
drag runs to keep it cool, but this is for drag racing and
I'm not sure it would help much.  Maybe reducing the boost
could help this problem (maybe with a manual boost adjustment

knob).

Anyway even N/A cars have that problem. If I am dragging>>and the engine gets heat soaked...the car feels sluggish as well.Then Juan Velasquez wrote: >I do remember>seeing some cars that mist water onto the intercooler during>drag runs to keep it cool, but this is for drag racing and>I'm not sure it would help much A couple of basic things here. First, from what little I know about turbosystems, I have read many times about water spray over the intercooler to help cool the charge. It should work. Regarding heat soak, that is very much a potential problem. Alex, what octane fuel are you running? Octane has a very real effect on heat soak. Higher octane fuel will transfer less heat to your engine. Yes, the thermostat controls the water temp, but the water has an easier time controlling the temp if there is less heat transfer. I guess that's a longwinded way of saying if you are not using the highest octane pump gas available to you, try it. I'll bet your engine will be happier with it. That goes for anyone who is experiencing poor performance in high temps. Although higher octane will not provide more bhp (except under certain situations where it will help maintain bhp), or add to mpg, it does have other effects that are beneficial to your engine

Well Alex I have some bad news.  The GTI-R's that Nissan ran in the
rally's all had a bad problem with overheating and cracking the heads.
We in fact have quite a few that run in our club and the only way that
they have managed to get around the problem is to fabricate a front

mount intercooler.

Well I think I am going to look into someway of cooling the intake charge better(I already use the highest octane fuel available to me so changing to a higher octane fuel as suggested is not going to help me). The idea of a front mount intercooler, sounds like it might help me but I don’t really want to increase the length of the intake that much (I want to keep turbo response as high as possible) so what I was thinking is how about replacing the standard air to air intercooler with and air to water one (thus keeping the intake length as short as possible) and then placing a radiator to cool the water at the front of the car?. The other option is perhaps water injection (not the spray onto theintercooler type) but the spray into the intake charge type, although I don’t like the idea of squirting water into my engine I do know that ithas been used with good results on a variety of other turbo cars.