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Discussion Starter · #1 ·
So I have this nifty new ecoboost but I'm not sure the boost is all that desirable (or necessary). I'd like to experiment with removing the boost, or selectively removing the boost, to see how the car performs as a vanilla, normally aspirated 4-banger. I'm guessing that the turbo provides less than 100 HP over the normally aspirated engine. Probably much less. Does anyone know what the HP/torque ratings would be without the turbo? Has anyone tried running with the TB connected directly to the air filter box? Or with the waste gate stuck open?

Thanks for your thoughts.
 

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You realize you posted in the "Performance" section.
 

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Why in the world would you want to do this? Just as a science experiment? Trust me... that turbo does add a SIGNIFICANT amount of HP across the powerband. I'm sure at the higher RPM's it adds more than 100HP (Crank).

Can you bypass the turbo, sure... but be prepared for all sorts of issues. The car's ECM is programmed to manage the engine's operation as designed.

If you want more economy out of the vehicle just KEEP IT OUT OF BOOST! Drive it like there is an egg under the accelerator.

The car weighs 3500 pounds. That little 4-banger under the hood is good for 32+ MPG on the highway at 65MPH. However to get it moving from a slow speed or stop requires judicious use of the go pedal. This is what screws the overall gas mileage up. Drive it like an octogenarian and she will reward you with great MPG's. Drive it like you stole it and watch the gas and MPG's go bye-bye!

U.M.
 

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Discussion Starter · #5 ·
I've read: "With only 6 to 8 pounds of boost pressure, a turbo can increase power output 15 to 25 percent or more over a naturally aspirated engine." I expect that this is all the boost pressure the wastegate in this system is designed for. If so this puts the boost from the turbo at somewhere between 45 & 75 HP. Given that the turbo was put in this car to reduce emissions I'm guessing closer to 50 HP. That puts the normally aspirated high revving 4 banger at somewhere in the 250 HP range. That's plenty of power for this little car. While the turbo is fun I'd rather increase the mileage by 15 to 20%. Eliminating or minimizing the boost from the turbo should accomplish this.

It would also reduce under hood temps which is desirable from a durability standpoint. After driving the car only a few times the heat build up under the hood is disturbing. I've decided to open the hood when I get the car home to allow the heat to escape. I want to open the hood in public as well but I can't afford the potential for missing parts every time I return to the car at the grocery store.

I'd be surprised if bypassing the turbo would cause the ECM/software problems. I've see non-aspirated cars with turbo kits installed without requiring mods to the ECM. Lots of these mods end up with a performance chip enhancement but not because it's necessary. The chips are added to add a little more HP.

Thanks for the thoughts though.
 

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I've read: "With only 6 to 8 pounds of boost pressure, a turbo can increase power output 15 to 25 percent or more over a naturally aspirated engine." I expect that this is all the boost pressure the wastegate in this system is designed for. If so this puts the boost from the turbo at somewhere between 45 & 75 HP. Given that the turbo was put in this car to reduce emissions I'm guessing closer to 50 HP. That puts the normally aspirated high revving 4 banger at somewhere in the 250 HP range. That's plenty of power for this little car. While the turbo is fun I'd rather increase the mileage by 15 to 20%. Eliminating or minimizing the boost from the turbo should accomplish this.
Well lets see if I can unpack this for you. The 2.3 Mustang Ecoboost motor makes 17-20 PSI of boost STOCK. So all of your following assumptions are incorrect.
It would also reduce under hood temps which is desirable from a durability standpoint. After driving the car only a few times the heat build up under the hood is disturbing. I've decided to open the hood when I get the car home to allow the heat to escape. I want to open the hood in public as well but I can't afford the potential for missing parts every time I return to the car at the grocery store.
The turbo does not create that much extra heat when it's not making boost. So again, if you keep your foot out of it it won't run that much hotter than an N/A car. Aside from all this.... that's what the cars cooling system is designed for.
I'd be surprised if bypassing the turbo would cause the ECM/software problems. I've see non-aspirated cars with turbo kits installed without requiring mods to the ECM. Lots of these mods end up with a performance chip enhancement but not because it's necessary. The chips are added to add a little more HP.
I never said bypassing the turbo would cause ECM/software problems. The ECM however will be very confused when all of its A/F table data suddenly doesn't match what is expected and it will make drastic changes to compensate. Your last three sentences show exactly how much you don't know about tuning and forced induction.

So please, go ahead and bypass that turbo and then record the results and post it here so you can show me how wrong I am on all this. I'd love to see it! While you're at it dump those direct injectors for a carb and regular intake.

U.M.
 

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Discussion Starter · #7 ·
That's VERY helpful. There are some aftermarket wastegates that have much lower boost pressures than 20. So I may be able to achieve more eco with a more eco minded wastegate.

As far as the direct injection goes I'd like to dump it for port injection (or even TBI). The carbon build up on the intake valves is a headache I could do without. I read somewhere that some of the TDI engines are starting to add a port or TB injector to minimize the carbon problem.

And you're 100% correct. I don't know anything about overcharging. Nor do I want to. It's an education I can do without. But I would like to un-boost the engine to up the economy. If a lower boost pressure wastegate can get me there (or close enough) then that's the path I'll go down.

Thanks for the help.
 

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Okay... if you are really serious, cause it seems like you are trolling.... Why mess with the turbo and wastegate at all?

Step 1. Connect intake directly to throttle body.
Step 2. Remove turbo and have a section of exhaust pipe welded/adapted to put in its place. (The turbo is going to be a restriction now blocking the exhaust gasses from freely passing through the exhaust system and will rob power)
Step 3. Remove all the unnecessary intercooler parts and piping..(Since you won't be using the Turbo and the TB is now connected directly to the airbox all of this is just taking up space and adding weight)
Step 4. Find a custom tuner and a dyno so you can have a proper tune made for your new configuration.

U.M.
 

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Oh sh-t, just pull the turbo, IC and throttlebody off and throw on a side draft Weber.
 
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