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Discussion Starter #1
I'm in the market for FI and while comparing kits here I read this about the TT:

"The turbo should be idled down for at least a minute after seeing any levels of boost (to allow the oil to cool the turbo)..." [BimmerDude18]

From what I gather, that this means the TT setup is oil-cooled and the idea is to run oil through it for a bit to cool it off so the heatsoak doesn't get too intense. I hear that this sort of issue is sidestepped when a turbo is water-cooled.

So first I'm wondering if is this accurate, second if it's only necessary in the summer, and third if water-cooling is an option with the TT setup?

Thanks!
 

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If you are hammering on the car you are building extra heat vs cruising, if you decide to stop right then all that extra heat just sits in the engine components including the turbo cartridge.

The idea is to let the car cool off, keep in mind you might see normal oil temps but the rest of the engine is still hotter then normal so when you shut it off the oil will just start absorbing that heat and burn.

Watercooling is mainly for DBB turbos because they use much less flow of oil, only for lubrication really, so they need another cooling source. Supposedly even with the car shut off the water will continue to circulate due to convection.




Just don't beat on your car then park it.
 

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I'm in the market for FI and while comparing kits here I read this about the TT:

"The turbo should be idled down for at least a minute after seeing any levels of boost (to allow the oil to cool the turbo)..." [BimmerDude18]

From what I gather, that this means the TT setup is oil-cooled and the idea is to run oil through it for a bit to cool it off so the heatsoak doesn't get too intense. I hear that this sort of issue is sidestepped when a turbo is water-cooled.

So first I'm wondering if is this accurate, second if it's only necessary in the summer, and third if water-cooling is an option with the TT setup?

Thanks!
The TT setup is functional with water cooling (the passages are there), but by no means is it necessary. All turbos have some sort of oil feed lubrication to the bearing, it lubricates and cools the charger. If you're beating it on the dyno and shut it off immediately without giving it a chance to idle for 15-20 secs, that's how to quickly destroy turbos... you're leaving the spinning turbo without a pressurized oil feed ... next fire up, expect white smoke- the turbo chra needs replacement. This is true for all turbo cars.
A min is severe overkill on the behalf of cautiousness. If you don't want to sit there (for less than 30 secs after boosting), waiting for the turbo to cool down, ever, I suggest looking into a turbo oil accumulator.
 

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The turbocharger used in our system is oil-lubricated and hence, oil-cooled. There are passages on the turbo to add water cooling if desired. Water cooling is not necessary though.

As previously mentioned, you want the turbo to cool down a bit (actually, stop spinning), before you shut off the engine (hence cutting off the oil supply). So all you really need to do is drive sedately during the last 30 seconds of your trip, let the engine idle a few seconds, and then shut if off and you're good to go.
 

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Discussion Starter #6
Thanks for the quick replies guys - that makes sense.
So I'm guessing that water cooling the TT kit wouldn't even really matter - it's not so much the heat as the risk of oil cutoff while spinning...gotcha

Well that sounds like a natural warmdown procedure that I probably do anyway without thinking so - not a big deal.

if anyone has any recommendations for timers or accumulators to check out for the heck of it let me know!
 

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So I'm guessing that water cooling the TT kit wouldn't even really matter - it's not so much the heat as the risk of oil cutoff while spinning...gotcha
it's both. If the turbo is still really hot AND you cut off the oil supply, the oil that is left there will oxidize (coke) and leave a nasty residue all over the seals/bearings, shortening their life considerably.

If the engine is running, that oil is quickly replaced by new oil and never gets hot enough to oxidize.
 

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Discussion Starter #9 (Edited)
Oops right - so the turbo can stop spinning and still be full of really hot oil that can hurt it.
So say I get a turbo, drive crazy, stop quick and shut off the car - but I have an oil accumulator - is everything ok?
Or does the accumulator not do much for cooling in that situation?
 

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Oops right - so the turbo can stop spinning and still be full of really hot oil that can hurt it.
So say I get a turbo, drive crazy, stop quick and shut off the car - but I have an oil accumulator - is everything ok?
Or does the accumulator not do much for cooling in that situation?
It's not that the oil is really hot damaging the turbo, it's that the turbo and surrounding components are really hot heating up the oil (that is no longer flowing) and ruining the oil, which then ruins your turbo.
 

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Discussion Starter #11
ok understood
and I now see bluejeans had already answered my accumulator question there...
thanks again guys!
 

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Discussion Starter #13 (Edited)
If running a ball bearing turbo, and you like to shut down the engine quickly and not worry about spool-down time, then this accumulator is what you need:

http://www.cantonracingproducts.com/cgi-bin/commerce.cgi?search=action&category=2415
awesome. it looks like I'll be going with this Accumsump :)
and it looks like I'll be installing the whole shebang with my uncle on his lift

any idea what other parts I should have on hand to incorporate this into the TT kit? (e.g. the suggested 1/4" Compression Fittings for Steel Turbo Oil Feed Lines 2 Per Package? a mounting bracket?)

whereabouts in the engine compartment should it be mounted ?
 

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Discussion Starter #14
update: turns out the TT kit uses a journal bearing turbo (not ball) and therefore the Accusump has been deemed overkill
 
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