Adding some cooling duct work

[Your Mom]

Last track day was about 80 degrees and my car wasn't taking cooling very well. 215 on output and 208 on input. The duct work i've had has worked ok but now its not enough. So i started taking everything apart upfront to add some duct work. Question is how?

you may be able to see the duct work here, i basically made 2 pieces that touch the rad and the intercooler. and attached them too the headlight supports. it doesn't cover all the radiator. i just bent the left one out today.
Problems i see in this picture is the hood latch kills a good bit of space. a carbon hood with side pins would allow me to chop the latch piece out. not gonna happen anytime soon, though. see the spacer for the IC, its making the IC tilt forward so its not a strait shot for air. I would think the IC and rad should be parallel. I already took it out today and made the IC more parallel but its not perfect. really could use a new IC. the greddy i have is a POS, seen years of beating, i can barley see through it. if i can sell the one i have i'll get a new one.


here the gap between the rad and core support isn't good, i ripped out the foam to paint. gotta find something to stuff in there.


Couple things i'm thinking of doing.
I want to run some duct work from the edge of the radiator to the bumper trying to cover all the area i can on both sides.
A piece on top of the IC to close some gaps.
Then a cooling plate for the GTR silvia grill piece i have
Stuff the open sides of the rad with something
fill the top gap between the rad and core
I might have the rubber piece for the hood that when closed touches the core support. don't have one on it now.

more pics for clarification




got any cool ideas or pics

[Your Mom]

thermostat was changed last year before TH to nismo one. I run distilled water with a bit of coolant and water wetter.

[Your Mom]

OH i forgot to add i'm taking out the 12" flex a lite fans and putting the stock shroud and stock fan/clutch on. I ordered up a brand new shroud last week from a nissan shop in CA for 53 shipped. stupid enjuku wants 100 not shipped.

I really hate changing too many things at one time but i really really don't want to have overheating issues this weekend. I've got slicks now thanks to monty and i want to find a new weakness with them.

ok i've whored enough, people gonna start calling me a_ahmed.

[veilside180sx]

A splitter would help a good deal, as it forces the air into the radiator/intercooler.

[cdlong]

fixing your intercooler is probably the best first step. get a fin straightener and clean that thing up. a lot more air will get to your radiator that way.

you could use some window sealing foam tape for the top of the radiator. you can get different thickness from home depot.

what does it look like with the grill installed? what about ducting forward from the IC to the bumper? is there a way for air to go around the IC and under the car? i would run some more aluminum from the front of the core support to the top on the grill, and from the front of the headlight supports to the grill. and from the IC to the entire opening in the bumper.

having the IC parallel won't make any difference. and removing the hood latch will help, but not much. mostly it causes turbulence, and having turbulent flow through a heat exchanger isn't always a bad thing.

[sr20goofus]

i run no ducting, on my car, but my FMIC is only an inch away from my rad. I also use the stock fan and shroud. At the end of a 80* track session my coolant temps will be around 190-200 with the stock thermostat.

i think the stock fan and shroud do way better than most people give credit.

[Cory]

You may want to consider a hood vent as well.

[2Fass240us]

What's the fin density on the IC? If you can get a less dense one in there, it will help with airflow to the radiator.

Other than than, I think you are on the right track with blocking off things. Splitter & partial underpanel plus hood vents sound like the best PoA. Speaking of which, I have a differential pressure gauge you can have for the shipping cost. This will allow you to measure the pressure differential between under the hood and on top, and show you empirically where a hood vent needs to be.

[SoSideways]

Stock clutch fan + shroud is the way to go definitely.

BTW I picked up a stock shroud, brand new, for $25 from Enjuku a few years ago when they had that big BBQ. It was on display as a "we want to get rid of it" item in the "clearance" pile.

I am so happy I got it.

Just need a brand new clutch unit for the fan and I'm good (don't want that thing to take a crap on me in the near future).

But yeah, like everyone else said, the most important "ducting" piece is the piece that goes underneath, like the stock piece of plastic. That piece alone will force a lot of air through the openings on the bumpers.

[Your Mom]

I got the bottom stock diffuser thing on been for awhile. we'll see what i can get done today.

A big splitter would be nice but that's more money i can't spend right now. i have a sheet and more of aluminum that i can mess with.

[McCoy]

Brian, I'd say do it in a couple of steps. For now I'd say start with sealing all the holes around the radiator to get as much air through the radiator as possible.

I installed the stock fan shroud finally and must say it's doing more than I thought it would, so I agree that getting the stock clutch fan and fan shroud installed is a must.

Find some hard foam that cuts easy and the sides only take 15-20 minutes of work. I just made sure that the foam cutouts were larger than needed and punched/stuffed them into place... no issues as of yet with them falling out.

[e1_griego]

I think the stock clutch fan and shroud will be an improvement, even without extra ducting and whatnot.

[Your Mom]

i think so too, but i did some ducting today. all i have left is to add a piece to the space between the rad and core.

made a out of cardboard 1st

then aluminum

Luckily the left side copied almost perfect to the otherside


Then made a piece that goes from the IC to the underside of the front bumper. and got the pass headlight in.

Made my own cooling plate that connects to the gtr grill


nice and tight

ready for this


if this doesn't work something else is wrong.

[McCoy]

That should work...

[flip240]

very nice, you make it look so easy, hehe