I think that sounds like a really cool idea! If the cutout is between the headers and the turbo, there won't be any boost. That would be a good way to take the load off the turbo if you wanted to, as long as you don't mind some extra noise.

 

There is no load on the turbo at cruise and putting around. Exhaust energy and volume is what drives the turbo and there isn't enough at cruise to load it up.

Basically, everyone agrees that it will not build boost and it'll be loud. I, for the life of me, can't figure out why these are good things. However, it won't hurt anything either.

 

I guess the only real advantage you have is that you could open the cutout and be able to give the motor the boot, while not putting heat into the turbo. This is if you want to get on it right after you start the motor (not really a good idea anyway, but worse if you are pushing it w/ a turbo), or just before you shut the motor off and don't have a turbo timer and don't want to sit with the car an extra couple mins to let it cool.

 

Not to mention it would give it that mean rumble at idle that the turbos somewhat muffle


Also, although it probably wouldn't be good for the turbo, it would be kinda neat to go to like 100mph at 4000rpms or whatever, then close the cutout so it is instant full boost


And if it's a street/strip car, I'm sure relieving the turbo of duty when you don't need it will extend the life of both the turbo itself and the engine

 

umm. negative. Just a guess, but I'm betting the turbo would still take about the same amount of time to spool up. If you're going to be accelerating wouldnt you just want to be using the turbo anyways??

You dont seem to be reading Mike's posts, or you're just ignoring them. When you're just cruising around, the turbo isnt doing anything!!!! It isnt under any load. Just because the shaft is spinning inside doesnt mean you're wearing it out any faster. Any difference in turbo life would be negligeble. And I fail to see how having a cutout open or cruising around with it closed is going to have any affect on engine life. It will however have an affect on the lifespan of your hearing ability.

 

And the other thing is that 18-wheelers driver literally 1,000,000 miles with the turbo loaded and spooled-up just about the whole time. I don't think we're going to wear one out.

 

Well I'm almost 1/5 the way there (195,000).

I see what you are saying now... not practical.

On a side note, is it possible to turn the boost down to 0psi for street driving?

 

Yes. There are lots of ways to set up an adjustable boost system. I have two in my GN -- one under the hood, and one in the center console. The under-hood one is more precise, so we typically don't screw with the console, but you could use that kind of adjuster to achieve what you want.

Note: If you're at 0 psi, then your turbo is already spooling up. A naturally aspirated motor has negative manifold pressure.

-Jake

 

Ahhh, forgot about that

Thanks!

Reason I was asking is I think some time eventually(probably 2-3 years from now) I want to get some major power from my car, and turbos seem to be the most efficient way to have a 500-600whp daily driver.

 

An 8.5/1 motor exhausting through a turbine is pretty underwhelming at 0 psi. I have a High/Low switch for my turbo. At Low, it goes to the base wastegate spring setting, which is about 11 psi. At 11 psi intercooled, 8.3/1 compression and 10/1 A/F ratio, I can beat on it all year and never break it, but still make 550 rwhp.

When I flip the switch, it applies pressure to the closing side of the wastegate and the boost goes to 20 psi, where the Methanol injection comes on and it makes 680 rwhp.