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Charge cooler sizing ...

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You shouldn't need a pressurised system unless the cooler core is seeing air temperature that'll cause the water to boil (100deg C or more).

 

That said, if it gets close you could get local boiling on the surface of the water side of the cooler and that would be very bad.

 

I'm going for a big front rad and some good size pipework with a header tank as big as will fit within the wheelbase. That most likely means in the boot. Cos the front is full and hot!

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I didn't say you *need* a pressurised system, pressure does just builds up providing everything is water tight, and the OE washer tank isn't up to it.

 

I don't buy the water hose size thing and I see that post has been changed since I last read it, LOL! I'd rather have a smaller bore evacuating the heated water faster than a fatter bore with slower flow. It's all hair splitting idealism at this level anyway.

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I don't see your logic. First you say a huge tank is important, but then you think that water volume in the pipes isnt. :?

 

Use a good pump and the flow isnt a problem (or even an issue)

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Sorry, maybe I didn't explain myself very well, they're both important and I (as in me personally) said I'd rather have faster flow through a smaller bore than a slower flow through a larger bore.

 

CC kits are built for purpose. If 2 car lengths of 17mm bore and 3 gallons of water more than does the job, I don't feel the need to run 32mm bore, which is completely impractical for a lot of road cars that run boot mounted tanks anyway. But if the water runs are much shorter and the tank capacity is smaller, then there's an obvious advantage there.

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Sorry, maybe I didn't explain myself very well, they're both important and I (as in me personally) said I'd rather have faster flow through a smaller bore than a slower flow through a larger bore.

 

CC kits are built for purpose. If 2 car lengths of 17mm bore and 3 gallons of water more than does the job, I don't feel the need to run 32mm bore, which is completely impractical for a lot of road cars that run boot mounted tanks anyway. But if the water runs are much shorter and the tank capacity is smaller, then there's an obvious advantage there.

 

Yes, thats the point, most people won't run boot mounted tanks so its advisable to run large piping to get the most capacity..

 

But in a big system, don't worry about water flow slowing down in a large system, as the advantage is the water flowing round is cooler as there is more of it, so its 'swings and roundabouts', but more water will always help heatsoak issues..

 

32mm is overkill... I only use this on the drag setups with the massive 6" and 8" cores which have matching cores with 32mm inlet/outlets. 25mm is the most advisable for road car systems.

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i dont think chargecooling has ever made it into page 3 before. usually dies of after page 1. bravo chaps,

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They're not as popular over here as they are in the states, but interest is steadily picking up.

 

Good kits are pretty expensive too, which puts a lot of people off, as does the added complication of water tanks and hosing etc. The effort is worth it though!

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They're not as popular over here as they are in the states, but interest is steadily picking up.

 

Good kits are pretty expensive too, which puts a lot of people off, as does the added complication of water tanks and hosing etc. The effort is worth it though!

 

Yeah, any idiot can fit an intercooler :lol: I think the problem is too is so may people have fitted CC's in the past, f*cked it up, had bad results, and then people tarnish chargecoolers as being 'crap', when in fact there are so many advantages - if you know what your doing 8)

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i've used them for a while. and i'm just getting my new one finished, just painting the pipe work matt black and its ready to go in. trying to go for the oe look .

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Yeah, any idiot can fit an intercooler :lol:

 

He he, not a Corrado VR6......bugger all room!! :lol: That's why I went with a chargecooler instead.

 

I think the problem is too is so may people have fitted CC's in the past, f*cked it up, had bad results, and then people tarnish chargecoolers as being 'crap', when in fact there are so many advantages - if you know what your doing 8)

 

You're spot on there. Even as little as 6-7 years ago the few Chargecooler setups I looked at were hopeless. The 'good' ones struggled to get IATs lower than 50 deg and one really, really bad kit rose IATs from ambient to 70 deg by the time the car hit 3rd gear :shock: That particular car need a supplementary air-air cooler aswell :lol:

 

These days CCs are much, much better!

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Lots to digest here! :?

 

A few of questions though for all contributors of this thread:

 

1) To avoid heat soak/rising water temps in a chargecooler setup, would you run the pre-radiator fan continuously?

2) What kind of boost temperatures would you see going into a chargecooler from a G60 running 14psi?

3) Given the boost temp for 2) above, what could the chargecooler outlet air temp be? (lots of factors, I know, but gimme a ballpark)

 

All that I've read so far makes me think chargecooler rather than intercooler or water injection, but it all depends on what you're after... :wink:

 

Thanks!

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Er, think I may be able to answer one of my own questions :oops: correct me if I'm wrong!

 

2) Assuming ambient temp is 18C (average) then air out go the G60 compressed to 14psi/1bar (eg. 68mm pulley on a rebuilt charger) would be doubled in pressure and hence doubled in temperature, to approx 36C...

 

So why does the boost pipework get so d*mn hot? Is it heat soak from all the lovely 100+C oil that's lubricating the charger? Heat soak from the hot engine bay into all those lovely black plastic boost pipes?

 

If so, would a standalone oil supply (as offered by Pitstop) and polished metallic boost pipes not be better options for keeping the boost temp down? Surely if the stock intercooler has to handle only 40C it would be a more elegant solution than having the charger body/pipes heat the air to nearly 100C then fit a massive cooler of some description to take all that heat away again???

 

I realise that there's some heat transfer directly through the metal mounts and fixings from the engine to the charger, which would be tricky to completely remove, but am I missing something here? :?

 

On that note, would people recommend an exhaust manifold wrap to keep temps in the engine bay down?

 

My bro (a Golf nut) says that the 8 valve non-crossflow engine suffers from heat transfer from exhaust to inlet as one is just below the other!

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Plumb in a thermistor type air temp sensor and see what the actual charge air temp is. I think you'll find it's a lot more than 36 degs. If it isn't, you don't even need a cooler at all.

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Plumb in a thermistor type air temp sensor and see what the actual charge air temp is. I think you'll find it's a lot more than 36 degs. If it isn't, you don't even need a cooler at all.

Thanks - good idea. I noticed on the forced induction VR6 thread that the late 1.8T temp sensor(?) is much more responsive than the stock Corrado unit, and that mounting it in the airflow inside the throttle body gives the most accurate readings for the ECU to act upon - is that also good practice and relevant for the G60 engine? If so, is there a VAG partcode to be had? :wink: And who can I get to bore a hole in my TB?

 

I think that most of the heat in the charger must be conducted through from the engine via the oil feed and the metal mounting brackets... Don't think it can be internal friction otherwise my charger wouldn't have lasted 85k miles and still be providing sensible boost. I'm no expert though! :?

 

A standalone charger oil supply kit would appear to keep the body of the charger (and the air inside) cooler:

"We have experienced [oil?] temperatures no more than 30

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You're right, you do get muchos largos heat soak under there. It's a very cramped place for a supercharger to live in!

 

Not sure what the part number is for the 1.8T sensor, but just ask the stealer for one off a 225hp TT. Yeah it's perfectly OK to use in a G60 for measuring purposes, but I'm not sure if it will hook up to the G60 ECU though. Don't know enough about the engine. Stealth Racing made my throttle adapter and fitted the 1.8T sender to it.

 

I'm not sure how efficient the Glader is in relation to other chargers but 36 deg at 14psi would be seriously good. Turbos knock out compressed air ranging from 70 to 170 degrees on full boost, depending on the boost pressure set, ambient temp etc etc. That's why cooling is important. Bimbling around on part throttle, the IATs aren't that critical, but a cooler than can't cope with full boost soon becomes apparent when you nail it :lol:

 

Standalone oil supply sounds like a good idea, which is how the Rotrex works. Even has it's own little Mocal type cooler too.

But as you say, the charger is still physically attached to a hot lump, which you can't do a whole heap about unfortunately.

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Thanks cheesewire.

 

Any G60 bods know if the TT's temp sender is compatible with the G60's ECU? Anyone, anyone?

 

I wonder if using phenolic washers between the G60 mount and the engine block would 'eliminate' heat transfer... One for the G-werks/PSD boys I think! I know G-Werks sell phenolic insulators for the inlet manifold, so perhaps the same principle could be applied here.

 

My '36C' temp for the air was a bit 'theoretical' and assumes that there are no other heat sources nearby that would significantly interfere with the simple process of compressing the air... Blatantly not the case in my current (stock) setup :(

 

But if the air coming out of the charger on full boost is only 40-50C because the charger body is not unnecessarily hot, then the stock IC may be able to hack it and give me relatively cool intake temps :D

 

What's the rule of thumb? For every 10C drop in intake temp, you have 3% more oxygen, so 3% more power available? 8)

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Yep, that it is the default Air temp compensation map, which Physics gave us :lol:

 

I'm liking your train of thought......doing more with what you've got rather than using counter measures to combat the extra heat of extra boost!

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Call me Mr. Retentive, but I like to get the basic package right before going for world domination :wink: :lol:

 

But it is a learning curve - getting to know what's relevant and what's not. Great fun though, and I foresee many hours spent trawling the forum for nuggets of knowledge!

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Just read spotted this thread coming back to life and just done a few tweeks to my setup that have improved things no end.

 

1.8t boost sensor is part number 058 905 379. Made a big difference to response on a VRT. Just check that you don't already have an open element sensor already. I think it's in the side of the boost pipe middle of the engine bay? The temp curve is very close so it should work fine on standard ECU, not identical though.

 

The 10" radiator from the Daves, fitted up front great without any cutting. But I did have to trim the fan brackets to get a bit of clearance. Again this is on a VR though, the G60 front is different (like a valver?) so you may have more or less room.

 

Ducting air into the charge cooler rad made a big difference, as did opening up the VR grill to get more air in. If you don't duct the air to the pre rad it'll take the easy route through the main radiator and the charge will eventually get hotter than your expecting.

 

The fan does run all the while, but it's not needed above about 45mph.

 

Some pics here of my kit and install guide http://www.the-corrado.net/.archive/forum/viewtopic.php?f=1&t=27844&st=0&sk=t&sd=a&start=75

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