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Discussion Starter · #1 ·
Abbott Racing is currently selling a heavily modded old stle 9k which among many other things has a gearbox oil radiator w/ an electric pump fitted.

Has anyone ever experimented with this modification to a 9k, and would keeping gearbox temps down lead to a longer life for the 3rd gear c-clip and the box in general?
 

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I have no experience of this in a 9000, but gearbox cooling is quite common in competition cars and becoming more common in road cars (particularly mid and rear engined ones) as everything underneath gets covered in to improve aerodynamics, downforce et al.

Remember that gearboxes get hot mainly because of power loss in the gear box, and that even normal cars' gearboxes get surprisingly warm on a high speed run. Presumably, Abbott have plumbed in a small oil cooler, a thermoswitch and the pump. Hardly high tech, and as long as it's been done properly, and does not effect the oil level when it switches on and off, should be OK. Even a small cooler should have a dramatic effect at keeping the box cool, and therefore prevent the oil from degrading with temperature. I suspect that modern synthetic gear oils will withstand higher temps than conventional oils, but I don't know much about 9000 'boxes as mine's an auto.
 

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Remember that the oil in the 9000 'box is an engine oil and as such a multigrade in itself, so it'll get thicker as it gets hotter. How hot is anyones guess, but dipping a cookery thermometer into the dipstick hole after a strenuous run ought to give us an indication. Anyone out there got one and like to give it a go?
Nick.
 

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The oil in mine gets warm but not hot enough to be uncomfortable, so lower than about 45c ish.

The auto's are cooled as standard anyways, could always mod an auto cooler C900 or 9000 for a manual....

Andrew.
 

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Johann Heuschmid told me I should install a radiator on my 9-3 gearbox if I should plan to go far beyond 300 hp. Seams like a good idea. I wonder why so few have done it yet.

Yours,

Philip
 

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Originally posted by cdcarlsson:
[qb]Remember that the oil in the 9000 'box is an engine oil and as such a multigrade in itself, so it'll get thicker as it gets hotter. [/qb][/b]
All oils that I can think of get thinner as they get hotter. Multigrades get thinner more slowly compared to a monograde oil. Perfecting the oil that has a constant viscosity across a wide temperature range is the holy grail of oily chemists.
 

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Originally posted by Scaero (Maptun stg3):
[qb]The oil in mine gets warm but not hot enough to be uncomfortable, so lower than about 45c ish.

The auto's are cooled as standard anyways, could always mod an auto cooler C900 or 9000 for a manual....

Andrew. [/qb][/b]
45 Celsius!! I'm amazed if it's that low after some high speed use.

You could use a radiator from an auto, which has a small cooler in the cool end of the rad, if it provides significant cooling. But you'd still need a pump and switching equipment.
 

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If that's the same car I saw a couple of years ago (green, I think?) Abbott fitted that stuff just because the owner asked them to. They didn't seem to think it was necessary.

Yes, an automatic radiator would probably be the way to go if you wanted to do a similar setup. Much neater.
 

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Originally posted by Mark B:
[qb]  QUOTE
Originally posted by cdcarlsson:
[qb] Remember that the oil in the 9000 'box is an engine oil and as such a multigrade in itself, so it'll get thicker as it gets hotter. [/qb][/b]
All oils that I can think of get thinner as they get hotter. Multigrades get thinner more slowly compared to a monograde oil. Perfecting the oil that has a constant viscosity across a wide temperature range is the holy grail of oily chemists. [/qb][/b][/quote]Apologies, you're right Mark. I was assuming too much from the basic numbers. The second number in the multigrade description refers to the oils apparent viscosity at 100 degrees when compared to a non-multigrade oil. I thought it refered to a straight index of viscosity. I stand corrected.
Nick.
 

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Originally posted by philip hs:
[qb]Johann Heuschmid told me I should install a radiator on my 9-3 gearbox if I should plan to go far beyond 300 hp. Seams like a good idea. I wonder why so few have done it yet.

Yours,

Philip [/qb][/b]
Indeed. Nearly all high-powered factory cars have them; the STi is a good example.

Adrian~
 

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I feel a purchase coming on....

sounds like a good idea
especially for track days where you are doing lots of the old lever stirring in a lap also lots of on and off the power in a low gear
ie lots of gear churning oil action...
 

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Discussion Starter · #12 ·
Am I right that the hardest part of adding a radiator to the 5spd would be how to tap into the gearbox case to draw oil in/out, fit a thermo-switch, and make certain the oil level stays constant in the box? Sounds like a job to be considered during a rebuild. Summitt Racing sells a huge assortment of oil radiators, pumps, ect.

Thanks for all the comments. Please keep us informed if anyone has a go at this. (sorry Ylee if this means the kids are going to go to bed hungry again)
 

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I have had good experience with a company called Think Automotive www.thinkauto.com from whose website I borrowed these words of advice:

Mocal and Laminova oil coolers are used for cooling gearboxes, crown wheel and pinion units, differentials and power steering pumps, here the primary problem is not so much concerned with avoiding bearing metal to metal contact, as in engine cooling, but in preventing loss of tolerances due to heat expansion of metals which in turn lead to greater friction resulting in a runaway spiral of heat build up.
Some gearboxes and all power steering pumps have an oil pressure system that can be tapped for oil flow otherwise a remote pump is required.
When designing an installation these pumps require a switch, either heat actuated or manual, pumping cold oil is not recommended.
Add extra oil to fill cooler, pump and pipes which must be at or below the normal oil level otherwise the oil level in the gear housing will be too high when the pump is switched off. When returning oil onto the gears do so after the point of contact to avoid pumping losses caused by cool oil. If difficulty is experienced in supplying ram air to an oil to air cooler we can supply a fan and housing. Use -6 (3/8" bore) hose.

Looks like the idea of using the radiator from an auto is out unless you can find a back pressure valve to prevent the cooler emptying when the pump is off.
 

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sounds plausible...
and not too expensive
My gearbox is being re-built at the moment so is an ideal time
My researches have found that there is no fwd gearbox made capable of handling the kind of power my engine is putting out
the nearest is quaife with one rated at 350hp...
x-trac and hewland's are at the 300 level
(they are also upwards of £7k!!!!)
so how to preserve this one...this sounds like a very good idea
One good thing is that the gearbox is using engine oil so normal engine oil coolers should work
Also I should be able to pick up some of the stuff s/h....
 

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Looks like the idea of using the radiator from an auto is out unless you can find a back pressure valve to prevent the cooler emptying when the pump is off.  [/b]
The other option is using the C900's in-lower radiator pipe oil cooler, that should be low enough.

Andrew
 

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Originally posted by BillJ:
[qb]If that's the same car I saw a couple of years ago (green, I think?) Abbott fitted that stuff just because the owner asked them to. They didn't seem to think it was necessary.[/qb][/b]
Yes, that's correct. It's more of a nice to have rather than a necessity.

AFAIK the failures that Abbott incurred on their track 9k were all mechanical that oil cooling would not have made any difference to.
 

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The next time someone's going to a track day or even rolling road session, it might be an idea to put some of those temperature sensitive stickers that you normally use on calipers on to the gearbox and see what sort of temperatures are reached.
 

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If you are upgating you gearboxes with an oil cooler then make DAMN shure the pipes/lines are VERY secure. It would be a pity to loose the box becase af a broken oil line witch is another reason for a lot of broken autoboxes!
 
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