Hi guys,

I sold my s2000 last year and got an 07 350z, planning on building a track car.

So far, I tracked my Z few times in SOCAL tracks, and I noticed my stock water temp gauge was rising after one lap.

Last week, I went to Buttonwillow Test day for a half day, about 85-95 degrees. First lap, water temp was at normal, but it was rising after first lap. I do not have this problem on driving long distance, and I was not redlining at the track too.

I am planning on replacing my AC condenser, Radiator and install Oil Cooler, but I was wondering if anyone else, who tracks their G or Z, is having Water Temp problem.

I am missing part of the under tray, may be thats causing bad air flow?

 

This is a common issue. Radiator and Oil Cooler should help. VQ runs hot!

 

I would fix the under trey first, but I heard it's the vhr not the hr that have cooling issues. ..... search around ive seen people talking about coming issues lately

 

Actually I do have the main middle under tray, but I am missing both fender liners. I am not sure if fender liners are part of under tray.

Would this interfere with the airflow going into the radiator?

I also ordered voltex wing, so I was going to build custom chasis-mounted front splitter to balance the downforce, and fix front under tray problem.

Anyone recommend getting fender liners?

 

I don't think missing the fender liners is the problem. I took mine off and I only had an overheating issue at one event. I had an off and ripped off my front splitter and undertray. It started overheating after I lost the undertray. It was also brutally hot and humid that day so not sure if it was undertray related or the scorching heat. I replaced the undertray and did not overheat at the following event. It was also much much cooler that day. Also check for air on the cooling system. These cars are notorious for trapping air in the system and thus could cause overheating.

 

You can also run your coolant system with a higher ratio of water. Water is a better conductor of heat. Some guys run with pure distilled water with a cup of coolant for color.

Water wetters like Redline and Royal Purple do help a little in the same respect.

 

I flushed my coolant right before the track day, but it didn't help. I think it got worse.

I will try adding more water this time when I replace my radiator.

 

I never experienced high water temps while tracking in the hot, humid South, but I did experience high oil temps before installing an oil cooler. Maybe do what Timmy said and try and bleed the system again. I've heard several times before as well about it "trapping" air.

 

https://my350z.com/forum/autocross-r...track-use.html

 

Having actively raced an HR-converted Z for the past few years, pverheating can be a problem. First, make sure both high and low speed fan operation is intact. This really helps in pulling air through the radiator. Using a decently sized oil cooler makes a difference, as does a bigger aftermarket dual pass radiator. Using Redline waterwetter and distilled water will help. Finally, SCCA and NASA rules mandate the use of fenderliners and they do help in directing airflow through and under the car.

 

Thanks dkmura, I will try them!

I thought about replacing my ac condenser too, since the fins are little damaged. But I will just try to fix the fins when I install my aftermarket radiator.

I am surprised that SCCA and NASA have rules about fenderliners. I was just curious because I have seen some race cars with fenderliners installed, so I thought there was a reason race cars still have them on.

 

Don't bother with the a/c condensore- unless it's so blocked that there's no airflow, it makes little difference. Be sure to mount your pricey new oil cooler with some 1/4" stainless wire mesh in front of it, or that too will get dinged. Both SCCA and NASA have those rules because they want some resemblance to the stock cars being raced.