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Intercooler questions

Posted: 19 Aug 2006, 13:47
by airhead
I have a 1.6td syncro. I want a bit more grunt out of the engine and Im thinking the intercooler option is the best so far. Is it a big job to fit one, is it expensive, where should the intercooler go, where should I get it, and what are the pros and cons? Will it increase wear on the engine signifigantly? What about fuel consumption? Will I get a big horsepower increase? Is it worth it? Are those my feet? :D

Thanks!

Too much to young,,,,,

Posted: 19 Aug 2006, 21:28
by Fritz
What you need is some 'Laughing Gas' mate, that will make it go like shyte of a shovel and you'll pi$$ your sides every time you boot it if you pipe some into the cab area through the air vents.

This mod is not the cheapest but is the quickest way of increasing the performance of your dosey diesel motor...


Regards

Fritz,,,,,,,,,, :shock:

Posted: 19 Aug 2006, 23:26
by HarryMann
Is it a big job to fit one,
Depends on the facilites and skills you have, and how tidy or get the job done finish you want.
is it expensive,
Depends how you source it. A complete kit ready to fit froma german suppleir could cost £350 to nearly a grand depending on how top-notch you want to go.
2nd hand sourcing a small VW intercooler and pipes ? the pipes are the fun part usually

where should the intercooler go,
If it's what are now being called charge coolers (air>water intercoolers), then the water radiator at the front and the intercooler close to the turbo.
If an air-to-air one, then again, as close to the turbo outlet as possible, many stick them in the rear quarter somewhere, some behind the rear n/s light with a fan (the very small ones)
On a 2WD its possible to fit a large i/c underneath, just in front of the rear cross-member - made specially. I have one actually. This thing will really make a difference to charge temperature, but its large
where should I get it
As above
and what are the pros and cons?
Efficiency of two things. Cooling the charge and losses in pipework. If the pressure losses due to convoluted pipework exceed any gains due to higher density then not worthwhile, though > if you leave fuelling and boost alone then regardless of power it'll reduce peak combustion temps, so no bad thing for longevity, esp those engines.
Will it increase wear on the engine signifigantly?
Why should it do that?
What about fuel consumption?
If it works well this depends on how much extra fuel you do or don't add, it won't make an enormous difference if you leave the fuelling alone, but should improve it a bit.
Will I get a big horsepower increase?
No, not big, unless you also up the boost and up the fuelling too.
Is it worth it?
If you want a lot more power, then as the boost and fuelling go up its a good thing to keep peak cyl and exhaust temps down (EGT) - the intercooler does this as well as improve the charge density, if its an efficient setup.
Thing is, the normal JX compressor to inlet pipe is very short and direct, so any tortuous changes here may lose boost pressure due to pipe losses. Usually you gain, but you want a decent intercooler that does knock a fair bit of temp out of the charge, to combat any losses

It isn't really worth it much on a std JX if you leave the boost and fuelling alone...

The easiest way to get more power is to increase the boost, up to 10 or 12 psi, and slightly increase the fuelling. That costs about £15.

But reliability in the long term may be compromised. the 1.9 runs quite happily at 12-13 psi boost, even more, and a fair bit more fuel before intercooling is really necessary, but put all 3 together and you can have a much more powerful motor with reliability. Keeping the charge density high is more important as boost pressures go up, as more heat is added during more compression.
It will also be slightly more more noticeable in very hot weather

e.g. nice to have an i/c but is not always the first step to increase performance.

Are those my feet?
Highly likely, but don't trip over them :wink:

Posted: 21 Aug 2006, 00:37
by R0B
there is about 30bhp difference between my 1.6td and a 1.6td passat intercooled engine i have.i believe.....

Posted: 21 Aug 2006, 00:56
by HarryMann
But not through intercooling alone Rob?
Presume thats a Robestimate or is it a VW figure for these two?

Posted: 21 Aug 2006, 01:14
by R0B
tbh i dont know.i was told this by someone else.who doesnt know either. it seems..

Posted: 21 Aug 2006, 01:16
by HarryMann
were they implying this is the difference an intercooler makes, as in just bolting one one :roll:

Posted: 21 Aug 2006, 01:20
by HarryMann
Perhaps I should have said, 'Ah, I see :roll: '

Posted: 21 Aug 2006, 23:58
by airhead
Thanks for that very detailed reply, HarryMann! Im strongly thinking about this option. I will want to certainly try it with higher boost and fuelling, and if Im not happy with fuel consumption or I think its stressing the engine, I can always drop it back. Now my understannding of the setup is that the intercooler is supposed to go between the turbo output and the intake manifold? Is this correct? Cause the kit that bernd jaeger used to sell seems to go before the turbo, ie: Between the air filter and turbo. Is that a half arsed measure or have I got it all wrong?

My plan for positioning is to cut out louvres on the guard at the bottom side of the engine bay down where the turbo is (Syncro) and put the intercooler behind there, assisted by a fan as well to get the most out of the setup.

Is 100bhp (or more?) concievable with this setup without stressing the engine? My understanding is that if theres more power coming from the engine, this increases wear and tear, thereby reducing the lifespan of the engine.

Posted: 22 Aug 2006, 00:13
by HarryMann
Is that a half arsed measure or have I got it all wrong?
Wouldn't think anyone would put it other than 'inter' the turbo and inlet manifold, esp. Bernd. Thats what the word means - to cool 'between' stages of compression.

My plan for positioning is to cut out louvres on the guard at the bottom side of the engine bay down where the turbo is (Syncro) and put the intercooler behind there, assisted by a fan as well to get the most out of the setup.
Going to have to be very small, and also thats a hot area isn't it... at least the pipe runs should be short. This is a difficult problem that I've mulled over a lot - and am current mulberrying over same for a close-couped oil cooler solution on the other side of the engine bay. The engine support bars are right where you don't want them...
I'm sure others would say just a small one in the box behind the taillight...but you'll still need a good fan, but note, its no good having a fan if the air can be exhausted - mount the taillight proud of the normal rear panel, and the vehicle draught should help create an exhaust suction - blow through front to back to help

the other option is to cut the bottom out of that box and mount it vertically behind the rear quarter panel a larger one can then be used with less fuss over the pipework too.

Is 100bhp (or more?) concievable with this setup without stressing the engine? My understanding is that if theres more power coming from the engine, this increases wear and tear, thereby reducing the lifespan of the engine.
the cylinder head is prob the critical component, indeed it is on the std JX and 1.6, maybe why a lot fit the 1.9 Head, with some mods to it, for valve area as well as more resistance to cracking between them.

I've read of 150 BHP and more from these 1.6 engines up at 5500 rpm + - without an intercooler. Its not the first thing a lot of the real way out guys seeking 200 BHP from these do... but we're talking very extensive pump and injector mods.

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Posted: 22 Aug 2006, 00:25
by R0B
if you look herehttp://www.busman.be/pagina45a.html you can get larger air intakes.do you think these would help much

Posted: 22 Aug 2006, 00:47
by HarryMann
Not really Rob, until you're doing 120 mph, the ram air effect (dynamic head :wink: ) just isn't worth much more than 1 or 2%...

The good thing about T25 vans is they pick the air up high, which on a hot day is worth MUCH more than any dynamic head effect.

However, if we're talking 150 BHP, then the mass flow rate would require a larger diameter inlet hose down from there than standard.

Used as an intercooleer feed, it would help a bit yes, but not much unless the intercooler cooling air exhaust could cope. As the ram effectis actually almost zilch until well over 100, as much or more work needs to be done thinking through the suction side of the cooling air's exhaust.

Think Airhead might have a Doka, so it would be important to pickup air well away from the very hot engine compartment that these suffer from - normally on a Doka it comes from the side inlet grille, behind the locker.
I have punched a lot of large holes in my Dokas engine access flap and then mounted the number plate about an inch or so proud of the flap's surface - stood it off. This i'm told now, is an old beetle trick - but I'm not kidding myself that it helps anything a great deal - but just doesn't actually do much harm. I've also removed the flappy crappy silencer shield from sheared off rivnuts, and fitted a thin stainless one on the silencer itself, again, maybe every little helps is the motto.

Mr Airhead - What I would suggest as Modicication No.1 - in fact insist on - is that a good oil cooler is absolutely imperatice with these engiens in this position. £300 from Busschmiede or you can sort a setup from here in the UK... this will do more to help longevity than anything else.

http://www.thinkauto.com/

Posted: 22 Aug 2006, 08:09
by airhead
Thanks for the advice! Plenty of food for thought anyway. It will be a while before I do it but nice to know I can with relative ease.

I have a transporter Im turning into a camper actually. She ain't a Doka. :D

Posted: 22 Aug 2006, 08:21
by HarryMann
Ah, in that case take Rob's suggestion to heart then... maybe without a larger intake, but use the left hand snorkel intake to feed plenty of air down to the intercooler, seal it all up on the inlet side so it will go through it, and make sure the hot air can get out somewhere easily to a alower pressure region behind. A good guide is that about 1/4 to 1/2 the frontal area of a radiator is the area of air that will naturally go through it, the rest will want to go a round without a shroud. A fan will be essential to make sure the intercooler has some sort of airflow.

Then the engine intake air mus come from right across the other side, the other snorkel, as you don't want this pre-warmed. the ducting can be insulated quite easily if it has to run across the engine compartment. It is not that importnat how long htis is, provided the hose/ducting is of adequate cross-section, 3" or thereabouts would probably do it (70~80mm).

Posted: 22 Aug 2006, 19:50
by Simon Baxter
Funny you should meantion this as I am in the process of getting together that parts required to build a oil cooler set up for the Diesel T3.
I have had a fairly lengthy discussion with a very helpful chap today about the very subject.
Some problems that may arise are that the cooler really needs a good air flow, fans are okay, but for it to work then it really need to be at the front of the van, which will involve just short of 10m of pipes. 10m of pipes means pressure drop and an increased oil capacity (not too much of a bad thing though)
Running a fan on a oil cooler, will work to some extent but nothing like what good air flow will do.
This won't be the sort of thing to bolt to a tired engine as a good strong oil pump will be needed to shift the extra oil around.
On my 2wd van I had a oil cooler between the fuel tank and gearbox, it worked really well, but on a syncro this would be uber bad!
The only way I can see it working effectivley is to mount infront of the radiator.
The kit will involve a take off plate which will be suitable for 1.6TD, 1.9TD and 1.9TDI, oil pipes and a oil cooler, all UK sourced and no bank charges to pay!
Once I have this kit perfected then the next step will be a intercooler kit, bigger injector nozzles, or maybe a charge cooler set up, Charge coolers are very expensive, and due to a lack of useable space for an intercooler then I think, performance wise this is the better option.
As the old saying goes "Theres no replacement for displacemement", meaning the best way to improve performance is to increase the cubic capacity of the engine.
The easiest/best/most affordable way is to rebuid a 1.9TD (AAZ), although ony 5 bhp more it packs a lot more torque and when in standard for is fairly well de tuned, a few simple mods can see this engine really fly and produce TDI like power but run reliably on a cable and use factory parts.