2nd Gen R56 Cooper S Most liked posts in thread: Heat Shield vs Turbo Wrap?

a heatshield works better on a turbo manifold than fiberglass wrap does. As for a turbo blanket vs. a tight heatshield....I'd agree with the good doctor.

 

it covers the turbo? I stopped caring about M7 long ago when Peter showed himself to be more concerned with image and profits than customer service and quality.

 

I would consider the M7 a manifold. The Way wrap is a tight wrap. The turbo can take the heat, the plastic bits can't.

Mark

 

right. Like the thread Orangecrush posted (on Nam not sure bout here)...his valve cover melted because the shield deflected all that heat right to it.

a tight fitting wrap is probably the best way to go. ... a heat shield with heat wrap stuck to it isnt going to do nearly as much

and Tim, you said it seems counterintuitive to wrap it tightly... Where's the heat go?...well it goes out the exhaust while the turbo is doing its job and building heat.

 

Weird, since the valve-cover isn't cooled by the coolant I don't know if I'd agree with that.
I always thought that a heat shield was to prevent heat going somewhere you didn't want it (like the hood scoop or the intake) while the wrap was designed more towards increasing exhaust efficiency by...well the exact physics for it escapes me at the moment... basically exhaust flows from areas of high heat towards cooler areas so wrapping the exhaust from the turbo to the catalytic converter retains heat in that area and improves flow to the cooler area behind the cat. I'm sure someone on here can give the exact scientific terms and some cool equations to match this.

You're right to be a bit concerned about trapping too much though, a rapid shut-down of a hot turbo stops the flow of oil and coolant through it and trapping even more heat in there can lead to increased coking, I'd think this can be avoided with some gentle driving before shutdown though.

 

Thanks for the cross link, I don't read too much of the sewing site these days. I only read the first page but I don't think idling down would've prevented his valve-cover from melting. He said he burned through the Kevlar under, I've seen other turbocharged cars with EGTs reaching 1200-1500 degrees but only under severe loading, I'd imagine this was when the Kevlar failed, once that was done the heat from the turbo was directed towards the valve cover and resulted in the melting. It's probably a pretty rare occurrence and most people with heat shields won't experience this. Back when most valve-covers were metal this was never an issue with a heatsheild setup, that and previously turbos would often be mounted lower on transverse applications from the factory. Now we've got a plastic that probably doesn't do well when subjected to jets of air in excess of 1000 degrees.

 

Tim...relevant cross references are always supported and welcome.

I'll jump on that was an extreme example boat too. But I'll also state that for heavy track use on modded R56 that heat shield may not be the best solution.

 

Has anyone actually documented EGTs on an R56? It occurs to me that although I'm more familiar with traditional multiport fuel injected vehicles with turbos and what their EGTs are that the newer direct injection engines can safely run leaner under a wider range of conditions which could mean the EGTs remain high even when not loaded.

 

We need Way to get in on this, but from what I understand, the internals of the turbo can take VERY high heat, it all the plastic bits around it that can't.

Mark

 

Dumb question but with the stock hood scoop, the grill only has about 1/2 of the honeycomb grill holes drilled out. Is taking a Dremel to the ones that remain blocked going to make any difference at all to improving airflow (and reducing heat build up to the hood scoop)?

 

It would help airflow and I think others have done that, but I don't think it solves the melting problem in the long term unless you never stop moving.

 

That could be the counter part to "always open"

 

I suggest that MINI, under warranty, start replacing the damaged hood scoops with the higher temp resistant carbon fiber units. It seems they have a fix waiting in the wings. Not sure what to suggest for the damaged hood stripes.

 

there's no need to run a modern turbo car before shut down. Turbo timers went out with the '90's. Modern turbocharged cars continue to circulate coolant and oil for a short time after shutdown.