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Fatheadrr

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Where do you live OP. Sounds like a waste gate might be opening to early. When boost drops at WOT does it come back
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OP
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Over a 45 minute drive, I tried several things. I accelerated gradually, then punched it after 3000rpm, I punched it earlier, I punched it in 3rd, 4th, 5th and 6th. Boost never got above 14, and never held while on the pedal, always dropped off.

1st sounds loud and rpms go up, but speed seems slower than rpm.

Down for a local driver to test mine, and for a Google Duo.

Thanks,
John
Where do you live OP. Sounds like a waste gate might be opening to early. When boost drops at WOT does it come back
This morning was the only time I've put the pedal to the floor, and only one time through some gears. It isn't something I'm keen on doing. Just a test.

Tonight's drive home was an improvement in boost. My commute is 95% highway. From 2nd gear onward, I shifted around 5500 rpm and boost was maxed out between 8-15 psi depending on the gear and speed. Didn't hammer the throttle in any gear, brought it up gradually, but with constant pressure on the pedal. If psi did drop while accelerating, it was only by 1-2 lbs, but came back up with additional pressure on the pedal.

To your point, my post this morning was about waste gate function, to determine if mine is operating properly. Assuming every clamp is super tight, and no leaks are present, it could be the waste gate. Right? A Google search earlier led me to a random forum and a waste gate solenoid. Don't want to speculate, though.

I live on Staten Island, NY. There is a forum member that lives here, though we havent crossed paths yet. I just so happened to click into a post he was active in. He owns a hatchback.
 
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Hollywoo0220

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You are just NEW to turbo applications. When you throttle back (even just a little) your EWG will drop your current pressure. However, if you are still in the higher RPM and in the correct GEAR you will build the pressure again (when getting back on the pedal). 5th and 6th gear will not build up pressure unless you are past the RPM that 4th Gear falls from. Your Si is built for running in the higher RPM, use it you will like it.
 

Fatheadrr

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You are just NEW to turbo applications. When you throttle back (even just a little) your EWG will drop your current pressure. However, if you are still in the higher RPM and in the correct GEAR you will build the pressure again (when getting back on the pedal). 5th and 6th gear will not build up pressure unless you are past the RPM that 4th Gear falls from. Your Si is built for running in the higher RPM, use it you will like it.
I agree semi with this. But if your WOT in 4th that boost should not drop until rev limiter is hit at high rpms
 


Hollywoo0220

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I agree semi with this. But if your WOT in 4th that boost should not drop until rev limiter is hit at high rpms
We really don't know. He could be experiencing a bit of "wheel spin" that is dropping his boost as well OR the intercooler is getting somewhat heatsoaked. Could be numerous things.
But, he has reported that his boost level has increased. I believe he is just getting accustom to this set-up.
 
OP
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We really don't know. He could be experiencing a bit of "wheel spin" that is dropping his boost as well OR the intercooler is getting somewhat heatsoaked. Could be numerous things.
But, he has reported that his boost level has increased. I believe he is just getting accustom to this set-up.
The car seems to like the higher rpms, in general. I learned that on the drive home. No wheel spin, my shifts are smooth.

I'll say it's part learning curve, and part me not yet knowing what to look for and expect from a turbo application.

But I also agree with Fatheadrr that high rpm in 4th, making 13-15 psi that falls while I'm still accelerating doesn't seem right. Even to the uninitiated, like myself.

Obviously, I'm going to continue to drive it and discover new breakthroughs. It's my only car, and I work in a neighboring state.

I really appreciate all the variables, guys. I really do.
 

PowerPerLiter

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THE BOOST WILL VARY BASED ON WHAT YOUR TELLING THE CAR TO DO AND THEN LIMIT POWER TO ADVERTISED. IT WILL NEVER BE THAT TRACKABLE FOR YOU.

If it had that large of an actual issue it would have given you multiple lights by now.

SMACK THE FUCKING THROTTLE DOWN AND LET HER EAT.

Sounds like you're wasting our time. Roll off from a stop sign at 10 mph and send it. Tell us how it feels and be sure your ready for second gear.
 
OP
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THE BOOST WILL VARY BASED ON WHAT YOUR TELLING THE CAR TO DO AND THEN LIMIT POWER TO ADVERTISED. IT WILL NEVER BE THAT TRACKABLE FOR YOU.

If it had that large of an actual issue it would have given you multiple lights by now.

SMACK THE FUCKING THROTTLE DOWN AND LET HER EAT.

Sounds like you're wasting our time. Roll off from a stop sign at 10 mph and send it. Tell us how it feels and be sure your ready for second gear.
Everything you're all capping I've tried. Clearly you'd rather flip out. No need to keep checking this thread.
 


Friction

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This morning was the only time I've put the pedal to the floor, and only one time through some gears. It isn't something I'm keen on doing. Just a test.

Tonight's drive home was an improvement in boost. My commute is 95% highway. From 2nd gear onward, I shifted around 5500 rpm and boost was maxed out between 8-15 psi depending on the gear and speed. Didn't hammer the throttle in any gear, brought it up gradually, but with constant pressure on the pedal. If psi did drop while accelerating, it was only by 1-2 lbs, but came back up with additional pressure on the pedal.
To echo other comments, you just don't understand how turbo cars work. Assume yours is working fine, bank your experiences in the "this is how a factory tuned small engine small turbo setup" functions. If you ever tune it, or change platforms, some of the characteristics will transfer to that new platform and some will be different.

You seam to be expecting supercharger performance that is mechanically driven and more predictable. The turbo is driven by exhaust gasses and has an internal bypass valve that the ECU controls. It spools based on the exhaust energy, if you're part throttle and accelerating, as the car approaches the speed it can do at the throttle position you're at and acceleration slows due to not being WOT, boost will fall.

That was the most basic way I can put it. Just drive the car and learn how it works.

I remember my first turbo car that I installed the turbo on and it was very weird and different from what I was expecting.
 
OP
OP

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To echo other comments, you just don't understand how turbo cars work. Assume yours is working fine, bank your experiences in the "this is how a factory tuned small engine small turbo setup" functions. If you ever tune it, or change platforms, some of the characteristics will transfer to that new platform and some will be different.

You seam to be expecting supercharger performance that is mechanically driven and more predictable. The turbo is driven by exhaust gasses and has an internal bypass valve that the ECU controls. It spools based on the exhaust energy, if you're part throttle and accelerating, as the car approaches the speed it can do at the throttle position you're at and acceleration slows due to not being WOT, boost will fall.

That was the most basic way I can put it. Just drive the car and learn how it works.

I remember my first turbo car that I installed the turbo on and it was very weird and different from what I was expecting.
The second paragraph was a helpful explanation. Thank you!
 

PowerPerLiter

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OP
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I know you think I am an asshole but if a compiled amount of knowledge and even general turbo car operation is what you seek...........

this is a thread I posted a while back and put substantial time and energy into
https://www.civicx.com/threads/atte...ion-how-to-prevent-blowing-up-your-car.40183/
I don't think you're an asshole, I don't even know you.

I just don't need aggressiveness when I'm trying to learn and rule out mechanical issues.

Thanks for the resource.
 

charleswrivers

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The second paragraph was a helpful explanation. Thank you!
Remember... I said the stock tune has partial throttle boost dampening. You generally will NOT reach peak boost unless you are floored. Even though the small turbo mechanically can reach full boost on partial throttle... and there is enough exhaust gas to do so... the ECU controls the electronic wastegate and will prevent you from reaching peak boost. It does this to make the car be far more linear than it has the potential to be... and that's what the tunes do... and why you can get a 50% bump in torque in the mid-range. It also makes the power delivery un-linear though. You get a surge of power In the midrange and the torque tapering off rapidly... though it is still higher than the stock tune.

The only other possibility that hasn't been mentioned... you keep say things about your engine working hard... RPM and speed don't seem to match. That... along w/low boost... would be indicative of a slipping clutch. When the clutch slips... your RPMs will rise... speed will no longer rise comparatively with RPM. Also... since the engine because unloaded because it and the drivetrain are no longer locked together... the engine is effectively not under as much load and can cause boost to drop because of the lack of load. Flooring the car at low RPMs in higher gears can cause it to happen.

OP... you'd really do best to have a passenger ride with you and record a video of what you're finding concerning if you want some more input... and even then we'd still be guessing, but there may be something you're not conveying well to us. Otherwise, we're all just playing the guessing game and we're not really going to get anywhere with it. This piece where boost is dropping at higher RPMs and the RPMs vs speed not matching and this and that is throwing flags to me... but it could be fine and you're just not getting the response you're expecting. So long as your foot is staying to the floor, I'd not expect what you're describing to happen.
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