Do any of you guys have any suggestions on reducing underhood temps on a
turbocharged car? With a properly bled cooling system with almost straight
water and water wetter, what other things do you recommend? I will put
washers on my hood bolts to lift the rear of the hood up. What else short
of Swain coatings?

vents over the exhaust manny area

I have an NX, which has been turbo for about a year. Ihave a twin core radiator, but otherwise nothing for cooling other than standard. Underbonnet temps measured with a digital meter havent been seen to go over 50 deg C. I drove it at mid summer, with a fully laden trailer with camping gear, a loaded boot and two people on board, and it didnt miss a beat..... Ive thought about bonnet vents, but it doesnt seem to need them.
I cant understand how cooling seems to be a problem, the radiator I fitted was just a precaution, I know of 3 people who are running thier original NA radiators, and have no problems???
Summer round here is in the high 20's ( C ).

How about Z-3 fenders? I do not like them but wouldn't that increase the flow in and suck out hot air? Just a thought.

Umm....high 20's C is not very hot. I'm talking about 100+ temps in Sacramento. I was starting to overheat in 90+ F temps in El Cajon with the AC on. Also, my fans turn on a lot. There is a lot of heat coming from the manifold/turbo area.

Bring back Jack. :D

Originally posted by 92SE-R
Umm....high 20's C is not very hot. I'm talking about 100+ temps in Sacramento. I was starting to overheat in 90+ F temps in El Cajon with the AC on. Also, my fans turn on a lot. There is a lot of heat coming from the manifold/turbo area.


Terrin

Well i have swained my exhaust manifold. Not sure if it "really"
helps all that much . Just going by the amount of heat emmitiing from that are it feels the same. In any case i have a Koyo radiator,
summit flexalite dual slim fans . On my way to and from Buttonwillow (no a/c ), yes i sweatin like a dog. IMy water temps were 190-200 degrees consistantly driving up there at 4000rpms.
never did it get over 203 degrees. It was 100+ degrees on the drive there from Antioch. Maybe you might want to try a thicker radiator and stronger fans if you havent already.

Using a combination of these two articles:
Eliminating Negative Boost (http://www.autospeed.com/A_0629/P_1/article.html)
Siting Cold Air Intakes (http://www.autospeed.com/A_1023/P_1/article.html)
One should, through exhaustive testing, be able to determine optimum locations of intake and exhaust venting on and around the front end of the car. Takes time to do stupid shit like this, though, and just a little bit of money. Finding out that a Pulsar SSS GTi-R hood scoop would actually be useful for injesting cool air would be neat. Fitting Z3- (actually more like Buick-)style hood vents in various places of low external pressure would be invaluable to releasing hot air efficiently.

How many SE-R people have actually done this? None that I'm aware of. Dr. Lew put some inexpensive vents and an ugly-ass (sorry, Lew) Z28-style scoop on his hood. Said those mods helped, but there didn't seem to be much science to his discovery and implementation processes. I could be wrong; he may have put it in a wind tunnel for all I know, but it doesn't look as good as I think it could. :(

For whom would this work? Everybody, but it would be body-dependent (Classics have different aerodynamics than NXen, which are different from B14s, which are different from B15s). The B15 was only offered in one body style, but I think that the aeros between the two- and four-door variants of the 13 and 14 platform would make testing on one body useful on the other.

If this answer is just too silly to fathom, just remember that you were the one who asked. ;)

Originally posted by Low612
Well i have swained my exhaust manifold. Not sure if it "really"
helps all that much . Just going by the amount of heat emmitiing from that are it feels the same. In any case i have a Koyo radiator,
summit flexalite dual slim fans . On my way to and from Buttonwillow (no a/c ), yes i sweatin like a dog. IMy water temps were 190-200 degrees consistantly driving up there at 4000rpms.
never did it get over 203 degrees. It was 100+ degrees on the drive there from Antioch. Maybe you might want to try a thicker radiator and stronger fans if you havent already.

Well my temps are relatively the same too. When driving in 100 degree weather my temps are always at 88c but while in traffic the most it goes up to is 95c(203f). This is with nothing, not even water wetter. Although if I beat on it and shift at redline it has hit 98c. Ive driven with the hood open too and still 88c, no difference. This is with the top mount there as well. By the way Larry what gauge and where did you place the sender for reference?

Originally posted by SucKit


Well my temps are relatively the same too. When driving in 100 degree weather my temps are always at 88c but while in traffic the most it goes up to is 95c(203f). This is with nothing, not even water wetter. Although if I beat on it and shift at redline it has hit 98c. Ive driven with the hood open too and still 88c, no difference. This is with the top mount there as well. By the way Larry what gauge and where did you place the sender for reference?


Im just using my techtom as reference. It displays water temp .
I cant really complain about my temps since Nx's all motor that i know of run hotter like 200+ consistantly.

If you want some decent hood vents, go to RoadRace Engineering's website. (roadraceengineering.com)They sell nice flush mounted style vents. Good luck getting in contact with them.

I get in contact with RRE all the time. The trick it to read the web page and find out when the busy times are. If u Email them don't expect a qucik reply because ur not the only one sending them email. I forget how much they get everyday but it's alot of mail. ohh got my 660cc Friday :D Mad bOoSt Yo

Well... as you will all learn very soon, it is not good to get me thinking. I'm the guy they were talking about when they came up with the saying "DONT GIVE HIM ANY IDEAS!".

As cowboydren said, nobody has taken the time to do this testing yet... the operative word being YET. I have ordered the equipment required to do such testing and will be conducting experiments shortly. see, now you've gone and done it.

Anywho, I have access to a 200SX, a Classic and my NX2000 so results will be posted shortly for all of them.

dude, terrin, get a NISMO or KOYO radiator, my fans dont turn on unless i have been idling (ie turbo timer) for over a minute standing still in the heat.

new thermostat will help. also, your intake would probably benefit from being in a "cold air" spot, away from the top of the engine bay where it is hottest.

also, you could make a scoop to catch under-bumper air and route it so it blows directly into your engine bay, as you have like 47 inches of ground clearance anyway and can afford some.

i also dont have splash guards anymore. they have been munched up from my attempt to cut them for intercooler pipes, them catching 140+mph wind (and no, not from JP's ass) and promply being ripped off, or shredded by my tires/pavement. seems to help with cooling at any rate.

According to Mike Kojima, those splash guards serve as a vacuum to suck in air through the radiator.

92SE-R wrote:
>According to Mike Kojima, those splash guards >serve as a vacuum to suck in air through the >radiator.

Which splash shields are they? I took the
ones on the bottom that are on either side
of the crossmember off, thought it would
help release heat better??

I do have the NISMO radiator and FAL fans.
They cool the car back down quicker than stock but
the overall underhood heat still feels pretty
high. Measured ~165F engine bay temp (not water)
in 95F stop and go and not getting on boost.

Those are the ones.

Raising the hood at the rear is exactly the wrong place to raise it; that's the highest pressure area of the hood. As low612 wrote, put vents over the exhaust manifold, the closer to the front of the hood, the better. Use reversed NACA ducts.

A splitter or deeper airdam will help, too.

Where can I get these NACA style ducts?

I'd check with Summit or Jegs, but last I checked, JCW had some, too. Any shop that does race car bodies should be able to get them if not have them on hand. You know what a NACA duct is, right? Kind of a teardrop shape, except there's a hole in the fat end. :)
http://speedmods.com/images/aa5bco1.jpg
Circle track racers use them to duct air into the cabin. They're commonly used for brake ducts on the sides of lower airdams. I'm not sure what the above poster meant by using them "reversed," but I bet you need to move a little more air than a NACA duct of a reasonable (small) size can handle. I'm also not 100% certain that a cowl vent is the worst thing you can do for your car. It's true that on older cars, this was a very high pressure area, but without testing (above), there's no way to be sure.

The Gonzo NX uses a GTi-R hood vent directly over the [F-Max -style] exhaust manifold and turbo; I think it looks funky, but you didn't ask me what I thought. Go ahead and pick up a JCW catalog and look at what's available; you just might find a "borrowed" scoop style that suits your taste and doesn't make your car ugly. ;)

I found some cool-looking options here:
http://images.google.com/images?q=NACA+Duct