2011 Boss Shinoda Level II FR

[Pastor_J]

I don't know the specs on this car yet but the car itself looks really good.

[TennesseeMustangPerf]

The Level 2 cars carry a full suspension system upgrade with control arms, lowering springs, exhaust, tune, gears, graphics, body modifications, interior upgrades... oh, and that little supercharger helps the car move down the road too. 
The level 2 cars are all supercharged, the level 3 cars are all turbocharged (with twin turbos an option).  SPV makes the world's most powerful production Mustangs, with performance to suit your needs all the way up to 1100hp!

[Pastor_J]

So what is the advantage of twin turbos over a supercharger? Do you get the turbo lag still that I got back in the late 80s in my Lebaron?


Don't laugh, I'm being serious. 

[TennesseeMustangPerf]

Turbos work in similar form to produce power as superchargers, however they are not spun off the engine belt but rather the exhaust exiting the engine.  Twin turbos give a couple of advantages.  The obvious being that the twins increase more boost than just one would as you double the air volume this will in turn increase boost pressure.  The other thing that they can benefit is in the fact that the compressors can be different sizes or stages.  This allows one compressor to operate at higher RPMs and the other to spool up sooner.  This allows the vehicle to generate low RPM boost as well as carry the boost throughout the higher RPMs as well.  Third way that it benefits is because two compressors operating at 10psi may generate a combined 16psi, for example.  Let's say that they do this while spinning off of 50,000 RPM.  That same setup and compressor may have to spin to say 75,000 RPM in order to generate those boost numbers, which in turn generates a lot more heat than two compressors would working together.  All in all, twins offer a very nice benefit.
As for the turbo lag, the newer designs in turbo compressors greatly reduce lag, and with a twin setup that may offer a low RPM spool and a high RPM spool compressor, turbo lag is all but completely eliminated.

[gunner_501]

The progressive boost of the turbo out performs the the belt driven supercharger hands down over ALL rpm ranges. I'm waiting to see what the different turbo companies come up with for the new 5.0 motor. I think Rob will agree that should be intersting.

[TennesseeMustangPerf]

Most definitely, Tim.  As soon as everybody can figure out that nasty variable timing system, you will see superchargers and turbos for the 2011 5.0L cammer hit the market.  That will indeed be a beast!  Start out with a 412hp car bone stock and THEN add forced induction... now that would be a beast for sure!

[gunner_501]

The tuner companies have to get onboard too. I think this winter will be an interesting time for all the aftermarket companies.

[TennesseeMustangPerf]

Agreed.  I am really excited to see what they do with the system.  Late fall to early winter is a good timeline, especially after November (SEMA).  I bet you will see a large aftermarket hit the new 2011s just before Christmas this year.

[Pastor_J]

I listened to an article on How stuff works the other day comparing Superchargers and Turbochargers. One thing that they mentioned is that one Nissan Skyline made for Europe actually encorporated both a Supercharger AND a Turbocharger. But according to them it was way to pricey for what you got.


The one thing that got me was that they said that most turbo companies recommend you let the car idle for up to 2 minutes before you turn it off if you've been driving a any speed to make sure that the oil circulates in the turbo before shut down.

[gunner_501]

Was that a turbo using oil from the engines oil pan or a sealed system? Sounds a little funny to me.

[TennesseeMustangPerf]

On a supercharged+ turbo car, the problem (well, main problem) aside from tuning is that running boost into a compressor to be double boosted just generates more heat than anything.  The compressors boosting boost does not increase volume that much, and the boost incoming into the compressor can actually slow the compressor down. 

@Tim,
Most turbos are indeed engine oil lubricated.  The only exception was an SCCA cup car that I saw.  It had an independent oiling system due to the dry sump engine oil system that created drainback issues due to the height of the oil canister.  Jamie is correct that most manufacturers recommend idling the engine a few minutes before shutting down any time the engine was used hard.  This is mostly to assist in the cooling down of the compressor though, as if it cools too quickly it can warp or crack.  It is even recommended on my F-350 after towing.