We get the intended purpose for the heat shield... and understand the hood scoop meltage... and are aware of the NAM thread... and all that jazz. :yesnod:
I've searched for evidence of cooked and coked turbos due to turbo wraps on modern cars with design and function similar to the MINI. I couldn't find any. Can you point us to some? Because this is a pretty common mod now on many turbo cars. Seems like we'd see lots of threads on failed turbos if what you suggest was the case.
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BlimeyCabrio Oscar Goldman of MINIsLifetime Supporter
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not to mention...if you're AT ALL concerned, drive for a few min at normal speeds for a cooldown - you'd be surprised at how quickly temps normalize.
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Here's more to think about...
if you keep the heat in the exhaust gasses, they flow faster down the pipe. The higher gas velocity also has more momentum and this results in faster turbo spool and scavaging (low pressure side of the exhaust pulse pulling more gasses out of the cylinder when the exhaust valve is open). There is no arguing the point.
Coking of turbos was a much larger problem than it is now. Synthetic oils are better at taking the high heats, and overall materials and cooling system designs are much better as well.
OCs valve cover melted because of insufficient cool down yes, but really, the heat shield made it so the really hot air had to go where it shouldn't and bingo! Without some instrumentation, we also don't know what the temps of the air that flow around the turbo gets to, and does it really warm up the valve cover more than without. The factory piece isn't there to protect anything but the hands of people who might touch it! That said, if he'd had a wrap I doubt that he would have melted anything, as the heat would have been held in the hot side and air temp rise would have been a lot less, even though it would have taken longer for the turbo to cool.
If I had an R56 S, the very first mod I'd do would be a turbo wrap. Then a standard hood (if it would fit over the engine and the like!)
If you're really paranoid, hook up a small Spal fan to blow air over the turbo after the car shuts off with a timed relay.
Personally, I think the "heat shields" are really a waste of money. Look good, yes, make the scoop last a bit longer, yes, but it's just working on a symptom (melting scoop) where the root cause is really poor heat managmenet. Fix the root cause, not the symptom.
Matt -
Thanks Matt! -
lotsie Club Coordinator
Thanks Doc, for explaining this all so well:cornut:
Now, can the DDMWorks Ram CAI get past the turbo heat? It uses the scoop opening to feed air to the intake. Or is this a whole other thread issue?
Mark -
Hmmmm
I'd just use the wrap and then it's a lot more of a non-issue. Also, there was a guy who had a shop around here that modified turbos. He'd port and polish them for improved flow, and use a thermal barrier coating on the outside of the hot side to do some of what the wraps would do. And it kept the hot side from getting that rusty look!
Anyway, like someone else posted, none of this is new stuff. It's just new to the Mini world....
Matt -
Hey all....
PGT, I agree under normal driving conditions but with track usage, I still think the car needs to cool down.
:ihih:
:lol:
With all due respect, I actually know that is not the case (at least for me).... remember, I've done roughly half a dozen track days with the heatshield (on two different cars) and never had any problems until this weekend which coincidently didn't melt until the last two sessions and both of those sessions were blackflagged. (no cooldown lap)
M7 is coming out with a new heatshield with a higher temp material. Though I think it will keep the heat coming upwards without burning the isolation material, I still think it would be a good idea to remove the shield for track usage. Unfortunately, the heat will still go backwards towards the valvecover.
Again, with a proper cooldown, it shouldn't be an issue.
Seems we're damned if we do and damned if we don't...
I won't wrap the turbo because I've got friends that have trashed bearings in their turbos from wrapping. (granted, none of them are mini owners but I would expect the same results)
I'm going to order an M7 hood scoop so when I remove the heatshield during track time, I don't have to worry about trashing my scoop.
Mark -
BlimeyCabrio Oscar Goldman of MINIsLifetime Supporter
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Mark - I STILL love you
I didn't mean nothing else contributed to your melted valve cover (like lack of a cooldown lap).
But what I DID mean is that, without the shield, I don't think it would have melted. Just because it didn't melt in the past when you had the shield on doesn't mean that it didn't contribute this time. That's like saying she didn't get pregnant the first four times we did it, so that proves I had nothing to do with it the fifth time...
Since we can't test the exact same conditions again without a cooldown lap AND without the heatshield, we'll never know... but the lack of melted valve covers on other cars suggests this was a factor. -
From past experience I would wrap. I dont want the heat just hitting the m7 cover and flowing in the wrong direction. I have wrapped in the past with no issues at all. Whenever you push a turbo hard you should always give it a cool down run.
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