Radiator question.. Core thickness/air flow

[3t-RA40]

Would be good to hear anyone's comments on that bottom splash guard as i haven't had it on mine for years either now.

[ace]

this is all great info guys......
just wondering why is a hyundai excel radiator so good? cmon its hyundai........
good quality? mounting points? cheapness?
cheers, ace

[TurboRA28]

I was chasing a radiator with slightly larger surface area than the ra28 one. Something that fitted in with minimal cutting/mods. Preferably alloy, as living right near the beach I find copper radiators only last a few years. Also alloy for the lightness. Cheap is a bonus too.

The hyundai one fitted those requirements.

I originally got interested in it when the AE86 radiator died. $450 dollars for a replacement wasn't going to help the bank account at the time. So i went to the wreckers with a tape measure to find something that'd fit. The hyundai one suited that well. $80 with a thermo fan on it! Couldn't complain about that.

After YelloRolla mentioned he was using one in his 3t-gte ke corolla also and thought it was a good thing.

So yeah just found them a good one to use.

Cheers
Joel

[phrostbyte]

I went hyundai for most of the same reasons as above. For one I had heard that it was a good one for cooling a 4A-GE, as the xcel is fitted with a 16valve 1.6L aswell, also it was light, alloy, and had a good amount of surface area. The thermofan that comes bolted to it is a monster and does an excellent job too .

Kev.

[Pure_In_Sanity]

Just something in regard to undertrays. I recall hearing a few years back that commodores with the gen3 engine suffered bad with temp increases when the undertrays were left off. They help direct as much air into the radiator as possible and also help draw excess heat out at the rear of the tray like Stu said- sorta a venturi effect.

[RiceburnaGTV]

Good timing with this thread,I was about to get the ta23 radiator tripple cored for my ta22 but think I will go down the hyundai route aswell,now all i need are some 13" 3 spokes big wing and a nike tick sticker to complete the picture

[phrostbyte]

Another question I was going to ask. As well known, heat rises, would bonnet vents (Not a scoop) help hot air get out of the engine bay? I would be thinking that most air getting through the radiator would hit the firewall and sit there heating up the engine even more. Only minimal amounts of hot air would go under the firewall and out...

[EldarO]

Kev, vents do help quite a bit, a cheap alternative to cutting the bonnet, maybe not for you because ke70's are plentiful, but for someone with a supra or soarer, like myself, is to put spacers at the back of the bonnet, effectivley making the whole rear seal of the bonnet one big vent.

youve seen it, commonly referred to as "dorifto style"

fairly cheap, very easy to do.

Eldar.O.

[oldcorollas]

this has been discussed before in length...

some vents help, some don't. placement and design are essential to making them work...

some vents, at speed, will stop air going out of the engine bay.

better way to get more airflow thru radiator, is to exclude air from going under the front of the car... that way the radiator air gets sucked straight out (as mentioned before in this thread)

[RWDboy]

From my extremely basic knowledge i give you this spiel :

The reason that under-trays generally work quite effectively is because the air behind the radiator is both hotter, and slower than the air as it was entering the radiator... meaning the pressure is higher... anytime that you have a pressure difference between one volume and an other you will get flow (in an attempt to balance out the pressure). The undertray serves two purposes, to act as a boundary to air flow underneath the radiator (to further encourage air to pass through the radiator) and also to ensure that the air behind the radiator is at a higher pressure than the air underneath the tray (resulting in extraction of the hotter, more pressurised air further back from the front).

Alot of cars have three piece undertrays extending from one wheel arch to the other basically because it encourages air to flow around the car (rather than under it) particularly near the engine compartment, and because it allows the air from the engine bay to escape out towards the rear of the car, and into a fast flowing stream of air (faster the flow, the lower the pressure).

Also the 'simple' explanation for using a thicker core is that it heats the air up more as it passes through. But you need sufficient air flow through the radiator and through the engine bay for it to be effective ... otherwise, as sort of explained above, you will just end up worse off than before.

In a sense - you should try and use the thinnest radiator necessary to do the job... if you have got excellent air flow, you don't need a septuple core 5-inch thick radiator - it just adds unnecessary weight to the car. If you use a single core radiator with good airflow in the engine bay - and it isn't doing the job, then you should think about something thicker.

Don't increase the thickness of the radiator though if you think air-flow is the limiting factor!

Increasing the size of the radiator (as in width and height) will help with air-flow through the radiator, but obviously with some cars there is only so far that you can go - and with some engines there is only so much radiator that you need. If you *can* put a wider or taller radiator in - then that will help.

It's hard to know whether air flow is limiting the ability of the radiator to cool down the water or not. If you are over-heating very quickly when opening up ye olde throttle (even on a cold night) - then my vague not-technical know-how would tell me that the radiator is either too small, or too thin. If it takes a long time to cool down (once you return to cruise-mode after a bit of a thrash when the water temp goes up) then you might tend towards thinking there isn't enough air-flow. Tough to say - sometimes you just have to experiment.

[takai]

Kev, vents do help quite a bit, a cheap alternative to cutting the bonnet, maybe not for you because ke70's are plentiful, but for someone with a supra or soarer, like myself, is to put spacers at the back of the bonnet, effectivley making the whole rear seal of the bonnet one big vent.

youve seen it, commonly referred to as "dorifto style"

fairly cheap, very easy to do.

Eldar.O.

And yet the back of your bonnet is a MASSIVE high-pressure area as it is already. Having it spaced up will do very little to your temps.

[RWDboy]

Some venting is better than none - and although the centre of the windscreen is very high pressure, there will be slightly less pressure towards the edges - where some heat will be able to escape.

It's not really a permanent solution - more like something you would try out on a really hot day out at a track rather than something you should use for everyday cooling purposes.

[Regina]

Just curious, would the distance between the intercooler and the radiator cause any great effect on heat in that area. Just trying to find a cause to why the core on my intercooler is hotter than inlet tank or exit tank. Possibly heat soak, via air, from the radiator? Or heat soak through mounting points between intercooler and radiator. The amount of heat in the core of the intercooler makes me think that it is doing little to cool the charged air and thus usless at this stage.

Mick

[RWDboy]

Probably because the air travels slower *inside* the core than in the end-tanks and hence is able to transfer more heat into the air flowing over the intercooler. If the end tanks were hotter you'd be worried!

[Enchanter]

I beleive the "dorifto" style bonnet gap is only good for lower speeds such as burnouts, slower drifting etc