Any cooling tricks you know?

[soldave]

Got a relatively crazy build in progress at the moment for my drag daily driver. I'm going for a 17cm housed HX-40 with a top-mount manifold and all the trimmings in my Evo III. To cut a long story short, if I want any chance of this fitting the radiator has had to be switched to a 24" long VW Scirocco radiator, and of course the a/c is getting dumped (foolish in Okinawa, but I've got to make some sacrifices). The radiator is going to be moved a few inches forward so that everything fits and because of intercooler and radiator placement I'm just going to be able to have 2 12" wide and 2.5" thick slimline pusher fans on it.

I'll be using Water Wetter, get a fan controller to bring in the fans a little earlier, and am going to heatwrap everything I can in the engine bay (can't do the manifold because of warranty implications but everything else is getting mummufied), but am still a little concerned about whether the radiator's going to provide adequate cooling when I'm driving around in traffic (in summer we can get temps around 33C with 90% humidity. Am I missing any tricks for cooling? All I can think of is trying to make some ducting for the front bumper to make sure that every bit of air possible gets to the radiator, but that's only going to provide cooling when I'm moving.

I know it's a general question but if anyone has some tips I'd be very interested to hear them.

 

[Craig_CD9A]

Oil cooling might also make a difference.. I've seen people make air guides in their bumpers to direct flow to the oil cooler.

 

[Rockabilly]

A push fan between the IC & the Rad at the IC output half sounds ok. A very thin pull fan behind the Rad
for the other half would be better than sending the hotter IC end through the Rad. The alternator won't
mind some air flow between the dump & the alt. You could duct air sideways between the IC & the Rad where
there is no fan. Run only 10 to 15% glycol just to protect the alli. Water runs a lot cooler than glycol.
Cheers !

 

[4piknup]

water to air intercooler to save having all that room up front stolen by a air intercooler.
i know you still need a watercooler radiator, but it will be smaller than a air intercooler.

 

[Gianni]

water to air intercooler to save having all that room up front stolen by a air intercooler.
i know you still need a watercooler radiator, but it will be smaller than a air intercooler.

Plus you you can mount it anywhere.

+1 for water to air cooler

 

[DOUGMO]

ducting will make the biggest difference if done correctly
needs to be all sealed an make the air all go through the rad

 

[milkandoj]

Run only 10 to 15% glycol just to protect the alli. Water runs a lot cooler than glycol.
Cheers !

I thought with the redline water wetter it had all the corrosion inhibitors in it so you dont need to run any other corrosion inhibitors or have a glycol coolant to protect the Al?
Either way if you did want to run some glycol you would need to buy just glycol (im not sure where you can get this anymore) rather than the coolant concentrate with a high glycol content in it, as they have their own corrosion inhibitors and the number one rule is done mix different coolants as the additives may react. So the water wetter and coolant together may not be a great idea.

Where the OP lives in summer he won’t need any anti freeze properties, but anti boil is a concern, the water wetter will not raise the temp the water boils at, only how quick the heat is transferred across the metal surface. So people (myself included) run a higher pressure radiator cap to raise the boiling temp of the water due to the higher pressure in stead.

When i put water wetter only in my car i did try doing som loggin before and after, i didnt notice a great the temerature of the coolant its hard to tell, maybe a degree or two possibly i though, but its hard to test under the same conditions and be sure and say it made a differnce. I dont need anti freeze where i live anyway so it wasnt a step backwards. The idea is the water with no coolant absords heat much quicker than having a glycol content and the water wetter breaks the surface tension more so aid's it transfering from the engine to the coolant further. That meant to be the theory anyway.

I was recently reading up on people using the sirocco style radiators with good results, i was actualy going to go down this path mysef but have other things to keep me busy now.

 

[BMGTZ]

since you will be changing the radiator anyway i suggest the following.

custom 2 pass alloy radiator with and external header tank. the header should have an inlet from the engine and a return to the radiator.....radiator then back to engine.

by increasing the volume of water to a larger than stock amount it will take longer for the total volume to "heat up". Hopefully the amount of time you require more heat rejection than the radiator can provide will be offset by the extra volume.

use a lower than stock thermostat heat range....76 degrees for example. that will keep the total volume in flow all the time.

If you find the heat rejection to be inadequite you can plumb an auxiliary radiator say inside the drivers side wheel arch...inline.

Lots of hoses but about the same hassle as the air to water intercooling

 

[CYBORG-X]

just pointing out the simplest of all mods, stick 8mm worth of washers on the 4 bonnet hinge bolts to raise the rear of the bonnet... and remove the weather strip

in aircraft dynamics, which started during ww2 with combat fighters. engineers found that too keep the engines cool the air intake to the engine had to be 1/3 of the size of the air exit of the engine bay. these were v12 supercharged engine having the dinger reved out of them, so they know what they're on about.

next.. basic airflow and turbulance through radiator heat sinks, shows that a radiator that has its overall direct air intake covered by 15% works more effeciently then 100% and in situations where air is forced onto the surface the turbulance impeads the flow, thus loosing efficiancy....

but hey, lets just stick to my first line =)

 

[soldave]

Thanks for the advice everyone. Well I looked a the Scirocco radiator I got and... well let's just say I'm a little afraid to breathe on it wrong incase the fins break! Think this radiator is going to be used as a guinea pig to find out how much space I've got. Can't fit a full 3.5" Scirocco racing radiator on there but I have seen an all aluminium one from JEGS which is 2-core and might be better for me. Will take a look at the sizes of everything once the project starts getting underway.

 

[caged]

I used a std half core honda civic radiator with a Hx35 on my gsr. Never got hot and had a solid 5hours spent on the dyno on a 41deg day. I was going to use a Scirocco but couldnt get one cheap. Make a good fan shroud, it will be the differance between overheating or not. I didnt bother using any ducting because if it did get hot the fan would come on and that didnt bother me (it didnt come on when drving btw). I havnt seen a 17cm housing on an hx40 before?? is it wastegated? is it a 60mm comp inducer or 58mm? Im going to be doing an hx40 pro (billet wheel) on a 4g63 in a few weeks, It should make good hp.

 

[htgsr]

Im not sure a racing radiator will solve your problem, I run a PWR radiator that works beautifully on the track great on the motorway but is hopeless in traffic because its designed to have a lot of air flow, I had to mount 2 fans that cover the whole thing just to keep temps down while rolling round town but on a 30'c day it will still hit 100'c

Just my 2cents

 

[warbo]

Another vote for the stack of washers between the bonnet hinge and panel. Simple, free, quick to do, and if you dont like it, very easy to reverse. Try putting your hand at the bottom of your front windscreen before you do the mod, then compare after!. Am about to do it to my 97 RVR due to the ridiculous amount of heat being trapped under the bonnet (IMPOSSIBLE to leave your hand on the bonnet above the head after been sitting at idle for about 30 min).

 

[soldave]

I used a std half core honda civic radiator with a Hx35 on my gsr. Never got hot and had a solid 5hours spent on the dyno on a 41deg day. I was going to use a Scirocco but couldnt get one cheap. Make a good fan shroud, it will be the differance between overheating or not. I didnt bother using any ducting because if it did get hot the fan would come on and that didnt bother me (it didnt come on when drving btw). I havnt seen a 17cm housing on an hx40 before?? is it wastegated? is it a 60mm comp inducer or 58mm? Im going to be doing an hx40 pro (billet wheel) on a 4g63 in a few weeks, It should make good hp.

It's going to be twin wastegates as I'm going twin scroll with a JM Fabrications top mount exhaust manifold.

 

[caged]

Another vote for the stack of washers between the bonnet hinge and panel. Simple, free, quick to do, and if you dont like it, very easy to reverse. Try putting your hand at the bottom of your front windscreen before you do the mod, then compare after!. Am about to do it to my 97 RVR due to the ridiculous amount of heat being trapped under the bonnet (IMPOSSIBLE to leave your hand on the bonnet above the head after been sitting at idle for about 30 min).

one of the problems with the washer trick is if you're involved in a crash, since its raised, it won't hook itself into the chassis and only crumple the front
it'll just go through the windscreen which is bad :unsure: I just remove the weather strip.

It's going to be twin wastegates as I'm going twin scroll with a JM Fabrications top mount exhaust manifold.

Yeah I assumed that. What I mean, was the factory 17cm holset housing factory fitted with an internal wastegate or a non wastegated housing??

 

[soldave]

one of the problems with the washer trick is if you're involved in a crash, since its raised, it won't hook itself into the chassis and only crumple the front
it'll just go through the windscreen which is bad :unsure: I just remove the weather strip.

Good call. I'd not thought of that before.

Yeah I assumed that. What I mean, was the factory 17cm holset housing factory fitted with an internal wastegate or a non wastegated housing??

From the factory I don't know.