What we all think about charge coolers?

[Turbo-Brown]

Hello!

Was thumbing through a book last night (yes I can indeed read!) and saw a piccy of a BMW engine of some sort (will scan the pic in tomorrow) with a charge cooler neatly mounted on top and, as usual, though "I could make one of those"

Anyone think it's a good idea? Would mean mounting another rad at the front of the car and carrying the weight of the cooling water around but they're supposed to be quite efficient.

Cheers!

Alex

[kam]

Not 100% on this, but from what I've read on other boards and forums over the years, aren't charge coolers the less preferred option to a good intercooled setup? Only used where space doesn't permit the use of a decent sized intercooler. Only what I read though, but I know some of the Ford Escort RS Turbo boys used to use these a bit back in the days instead of larger intercoolers. Now they all prefer the larger gaping mouth look front mount IC's!

[kam-325i]

They are used, or were, when space was not availble for a large intercooler.

They are better, but a same size charge cooler as a intercooler cost more

[chrisr29]

I think they work best in marine applications where they can achieve 100% efficiency or better by drawing in sea water that's below ambient. In a car, I suspect they are no better than a normal intercooler......just a shed load more costly!

[Morat]

Don't they suffer from heat soak? Surely the water heats up and has to be cooled so you're back to square one....

[Turbo-Brown]

You move the heat to the front of the car which will only heat up under boost or when the charge air temps's above ambientish.

When you're cruising, the circulating water will be being cooled by the rad at the front and the intake air too.

Whereas an IC can heat up quickly, the water will take a while so you get a greater capacity for sudden bursts of heat......as I understand it.

[chrisr29]

Looked into using one myself utilising the air-con rad as a water cooler. But I figured by the time I'd bought the charge cooler, pump, reservoir, pluming etc I'd prob be into the thick end of 300 quid. Where as a brand new, ally intercooler cost me £100.

Would be an interesting project to try though. Maybe put the reservoir in the boot and plumb it with metal pipes running under the car, which would help shed heat as well and even-up weight distribution to boot.

[tim-ix]

I'm no expert but won't the intake charge have a shorter distance to travel with a chargecooler rather than an intercooler? Will this have any effect on turbo lag or is that dependent on turbo inertia and manifold volume?

[Turbo-Brown]

I had thought about the benefits of having a smaller intake system and I'd tend to agree that it should improve throttle response too.

[appletree]

Matts dad here
Just spent 20 mins writing a post previewed pressed preview then back lost the whole bloody lot dont care any more

[appletree]

Matts dad here
Try again try this link http://www.alertmotorsport.com/intercoolers.htm Matts going to use an home made version of this. As you know Matt is using a manifold mounted supercharger and this set up lends itself ideally to his install . Set against it is the cost of the pump and rad also the individual cylinders are less likely to recieve the same temperature compared to air to air (the post I lost read much better than this one) If i recall correctly water absorbs something like 8 times the amount of heat volume for volume, many things come into the equasion air and water velocity coling surface areas metal conductivity etc and of course the cooler is much smaller. Like you I imagine the cooler won't have much to do off boost and should have some thermal inertia which will be an advantage, on the track things wont be as good on the plus side lag should be better. Some books suggest this cooler is best if you put ice in the coolant tank (although they are talking short duration dragsters etc). Overall I imagine Air to Air would be best especially if you have a lot of heat to get rid of and space/neatness is not an issue Does anyone have any ideas for a 12v coolant pump?

[chrisr29]

12v coolant pump; plenty on ebay. Caravan accessory shops sell them as well.

[Turbo-Brown]

Was thinking of getting a bilge pump from (or for I guess) a boat for it.

I've read that water and aluminium exchange heat 14 times better than air and aluminium so you should be able to get an old intercooler and have the charge air pass through where the cooling air used to, and the water pass through where the charge air used to.

Having given it some thought, I reckon it'd be easier to fit a reasonable sized additional rad infront of the cooling rad than an IC. Once I master (yeah right) welding ali with my TIG I'm gonna give a charge cooler a go using a sierra cossie IC as the heat exchanger and have a poke around the scrappies for a suitable rad.

The air plumbing should be significantly simpler too as I intend to make another set of throttle bodies so as to lose the standard inlet and the air's only gotta travel over the engine rather than round the front of the car

[chrisr29]

Bilge pump should be plenty powerful!

As an added thought try making the reservoir out of something pourous.....pottery for instance....then the effect of the coolant evaporating through it's walls will act like a crude refrigerator, removing even more heat....

[appletree]

Yea
I was thinking about using somthing porous when i was awake at 4am this morning i came up with a clay land drain with a plate glued on each end fed with evaporator water then the coolant pipe passing through that, the air passing over should drop the temperature by what is known as the latent heat of evaporation (the energy that would be required to evaporate that amount of liquid at that temperature and atmospheric pressure). Dont tell anyone about any of this or they will send some men round in a little black van with some pills and a straight jacket Matts dad

[gareth]

i was thinking about this a while ago... my idea is a follows:

use a small locally mounted charge cooler (old subarus have them afaik) and use the spare wheel well as a location for a cooling tank. a huge radiator can be positioned horizontally under the boot floor and uses a duct / scoop for airflow. there must be room for some absolutely massive thermal inertia with a big tank too.

the fun bit involves using some parts from a cannibalised caravan / motorhome fridge or similar to chill the water in the tank
even though the refrigeration unit will never be able to keep up with the heat input from the hot air charge, there will be the large thermal inertia within the tank and lest face it, you're not going to spend enough time on boost to actually heat the water up a significant amount

an example of why intercoolers are naff was in my bros crappy uno turbo he had a while ago (150 notes, thank you very much!!!). on a full chat launch you could feel the intercooler cooking and losing efficiency before you were in 3rd! if you then cruised for 30 secnds it was nice and cool again. this is because the only thermal inertia available is the small bit of thin aluminium of the intercooler and it is totally dependant on airflow for constant cooling. high speed stuff was ok, thrashing about town just cooked it and it was only good for about 5 seconds on full boost.

this was with a standard small intercooler, standard engine, tidied up inlet tract, decent filter and a capri cherry bomb backbox, the boost limiting fuel cutout disconnected and the boost wound up 'to the max' in an attempt to kill it!!!!

[jkarran]

It really depends what you're wanting from it.

There's a lot of sensible posts already above but I would add...

Downsides: They're more complex than air/air as you have all the air plumbing + water plumbing + rad. If they corrode or burst your engine swallows the cooling water and goes pop They add the weight of the cooling water, pump and plumbing, often high in the front of the car.

Upsides: You can get better than 100% efficiency with a good setup and ice for short periods, ideal if you're into drag racing. No awkward plumbing out in front of the car. Compact and neat.

Comments: Can be combined with air/air cooling to improve efficiency if you already have air/air cooling, I think it was Renault did this on one of their 80s F1 cars. You might find a home built effort flows and cools better if you pass the water through the core and the charge air over it (opposite to normal air/air), be sure you use a corrosion inhibitor in the coolant!

jk

[Turbo-Brown]

Ah haaa!

Here's the piccy that spurned the whole idea:



Looks a bit like an M30 to me only with some crazy dizzy drive running off the front of the engine. Also I thought the oil filler was at the other end on the M30 so I'm probably way out.

Anyway, I'm keen on the idea as it massively reduces the complexity and size on the inlet side of the plumbing, and water hoses are easier to route than air piping as they're quite a lot smaller in diameter.

[Toby_Unna]

the older non motronic m30 has a dissy drive like that. and the water pump mounting looks similar as do the cam cover bolt locations and breather.

i'm going for e28 528i motor or something like it



edit: where's the throttle body? twin setup before the chargecooler?

[Turbo-Brown]

Wonder who made it. Looks like a nice piece of work with the cast plenum / runners and the injector bosses being pointed neatly down the runners.

Think it just looks right too, and I've convinced myself it'll be easier to get a reasonable sized rad in the car than a big IC.

I had wondered about the TB myself, perhaps it's incorporated into the inlet to the plenum and not visible in the piccy.

Seems like an odd way of doing it to have them before the turbos to me, would've thought that'd suck oil past the compressor seals with the throttles shut.

[appletree]

What book was the picture in?

[Turbo-Brown]

"Maximum Boost" by Corky Bell (no laughing at the back!)

[Andy335Touring]

[Turbo-Brown]

the self same

[Toby_Unna]

the older non motronic m30 has a dissy drive like that. and the water pump mounting looks similar as do the cam cover bolt locations and breather.

i'm going for e28 528i motor or something like it

i wonder how old that chargecooled set up is - the engine in the pics seems to resemble the seventies 2800CS engine

i guess it's later than that though.