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Discussion Starter #1
I've been mulling over and exploring options or a while now about ways to improve the cooling on my 9000 in the summer- especially for track days.

The cooling system itself is in good nick with a newish radiator and has been thoroughly flushed and cleaned.

The main reason I run hot is because of the obstructions in front of the radiator- namely the bumper
, the A/C condensor and the large intercooler. I've lifted the back of the bonnet to allow more hot air out, but it still runs pretty warm.

I don't want to throw the A/C away, alhtough thta woudl be the most obvious fix. I am considering removing the fins between the refigerant pipes on the top section.

One of the biggest compromises to cooling is having to run glycol-based antifreeze. After a hose leak, I was forced to run a mainly water mix for soem miles before I could get a fix, and the reduction in temperature was very significant. You don't want to do this for long though on an aluminium/iron mix system as electolytic corrosion will take place.

So I was wondering what could be used as an alternative corrosion inhibitor and thought that perhaps central heating inhibitor might be suitable- after all it has to do a similar job in systems that have a mix of steel, copper and aluminium.

So, assuming I get the concentration correct (this can be checked by ascertaining the electrolytic voltage induced, which IIRC should be less than 0.1V) can anyone think of a good reason why this shouldn't work?
 

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Mark,

I can't see why something like 'fernox' wouldn't work in the summer (no good for winter though).

Also, have you tried adding a few drops of non faoming detergent to the header tank? possibly something like driveway cleaner to remove the surface tension and let the water get in better contact with all the metal bits of engine and rad?

Andrew.
 

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Something called "Water Wetter" is frequently used here in the states. Especially in the climate I live in. Also, have you tried rigging up a manual fan switch. My C900 used to run quite hot, but I found that if, on hot days, I ran the fan constantly around town the temps would stay quite low.

If you ever build an engine again, consider ceramic coating pistons, combustion chambers, valves, exhaust etc. I don't want to start a new topic about that, as it's hotly debated, but I do know for certain it drastically reduces engine heat.

As for the anti freeze, the red stuff lasts longer but is less effective than the green. If you're running the green stuff there might be some way to upgrade things. Here's an interesting link to a site that sells electric water pumps. It would take far too much modification to do easily, but if you ever come to that point it could be usefull. They flow much more than stock water pumps, and because they can be turned off you don't need a thermostat. You can also make your cooling system reverse flow which is much better for both performance and reliability. Anyway .. just some thoughts. Hopefully you won't have to remove the A/C.

Yours,
Dubbya
 

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Adrian,

please don't mention electric water pumps - you'll make Mark E come out in a rash.

Mark E,

Do you still have the mesh grille? If so, I'd remove that for track days (remember that mesh screens are used to stop draughts in many convertibles). You could also start a new fashion by drilling lots of great big holes in the mid section of your bumper (with small "computer type" fans in them!). On the other hand, you could just go to a radiator specialist and get them to make you a heavy duty (high density or extra thick core) radiator.

Of course the other question is: Are you really overheating? The Saab gauge (at least of your/my vintage) seems fairly frisky in the "hottish" temperature range. Do you have any real temperature readings to justify your concerns?
 

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Discussion Starter #5
LOL EWP- well I learnt my lesson there Mark- but I am still going to look at using one as an auxilliary pump next year. Adrian, this was before your time so to speak, but basically an EWP doesn't work on the 9000 due to the pump chamber configuration. It will work very well on cars with less sophisticated cooling systems.

Yes, on my last track day I did take the grille out but it didn't make a huge difference.

In saying I run hot I mean that the temp gauge was permanently beyond the point that the fan cuts in.

I've thought about the bumper option, but decided it was too difficult, and I'm also considering fitting a couple of scoops (normally used for brake cooling) inbetween the foglamps and lower grille and then trying to duct that air to the area behind the bumper.

Yes, I also use water wetter and it helps a bit...
 

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Read the post on the attempt at an EWP. Makes sense that it would have trouble with all the stock engine bypasses being at just the wrong points for it to work.

If anyone ever builds an engine again, it might be more work that the result is worth, but you could do the replumbing necessary for making it work correctly. Plug off the return lines, move the heater pick up line to somewhere else etc .... just a thought. It would eliminate the need for a thermostat from my understanding of the post on this, which I suppose is one less thing to go wrong. Maybe a lil too much work just for that though ...

Cheers,
Dubbya
 

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I have used water in computing systems for cooling, and there are some substances whick are water wetters, and they still protect against corrosion in aluminium and copper. I will try and find a product name for you.
 

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Here's a thought ... for track days adding some sort of front lip for the very bottom of your front end. If you can direct more air away from the underside of your car it will create a stronger vacuum and pull more air from your engine bay. Might make a little better cooling. Of course it would be difficult to fit a lip strong enough to withstand high speed, and a good effect kit is both somewhat unsightly and expensive. But it's a thought for future Saaber's who may eventually encounter the same problem.

Yours Truly,
Dubbya

edit: Also some older Muscle cars in the US had "Cowl Induction" hoods. It works kind of like raising the back of your hood as you do now, but more so. I'm sure you're familliar with them. Sort of a reverse scoop. Pulls air out of the engine bay and if low enough, doesn't look at all "ricey".
 

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Actually, from what I have read about the cowl induction setups is that it will push air into the engine bay from there since the base of the windshield is a high pressure area. But then it may push air through and down out the bottom to help cool the bay. So still a good idea.

Another thing that can be done, is to shroud the front side of the intercooler/radiator opening to force as much of that air as possible through the core. Hirsch was explaining that the air will build up at the front of the rads and then dump around the sides versus all of the air passing over them. So a good thing to do will be to seal off/shroud the top, bottom and sides of the rad/intercooler area so it forces the air through the core better. Makes sense to me. I will be doing it to my intercooler to help make it more efficient at cooling the intake charge.
 
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