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Discussion Starter · #1 ·
I know mostly everyone here looks for top peak power/performance/acceleration, but im looking for a different approach.

Im not interested in top RPM power but low to mid. Im looking for acceleration and torque on the low to mid end.
Besides a tune which is a must, what other things can help/improve low to mid acceleration/torque.
My car for some reason doesnt like it when i go past 5200 rpms. Starts cutting off power drastically no matter what plugs I use.
Tried BKR7E and BKR8EIX, and both do the same thing but it does it less with the BKR8EIX

Im looking to build a good back roads/track acceleration cruze.

Mods in mind are:
Upgraded clutch system
Lightweight Flywheel
Tune obviously
Short Shifter from DDMWorks
Turbo Downpipe
Already remove resonator and muffle and replace with Trush Glasspack
CDV Deleted

*not a noob but not a professional either - So any input/opinion/recommendation is well received.

Thanks in advance
 

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The Best Acceleration Plugs are the Denso IK'22s ....Way Way Better than all of the NGK's.. Its not even close....The downside is they only last 10k...
 

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A tune doesn't really seem to help sub-2500 RPM acceleration in the manuals. They do pick up in the 3-5K range dramatically though.

Downpipe, catless exhaust, and a forge bypass valve all help spool quicker and hold boost better.
 

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Discussion Starter · #4 ·
A tune doesn't really seem to help sub-2500 RPM acceleration in the manuals. They do pick up in the 3-5K range dramatically though.

Downpipe, catless exhaust, and a forge bypass valve all help spool quicker and hold boost better.
That sounds great, i know it will be hard below 2500rpm, but from 3 to 5k that sound great. forgot about the forge BPV, will add that to the list. Thanks!!!

I wanted the Forge BOV, but for some reason i just dont like how that one sounds.
 

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Discussion Starter · #5 ·
The Best Acceleration Plugs are the Denso IK'22s ....Way Way Better than all of the NGK's.. Its not even close....The downside is they only last 10k...
Dont mind the 10k maintenance, im used to it, had same type of plugs on my previous car. Will definitely try those to see if i get better results.
Do local shops sell them or only online?
 

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2014 Cruze Diesel, 2007 Cobalt, 1981 Camaro Z28, 2017 Volt
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Dumb question: you are running Premium, right?
 

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Okay - just needed to make sure we knew all the facts...it should not be cutting out there, that's still peak power. Weird...
 

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The biggest issue you're going to run into is the 87 HP 1.4 engine. You need to pull more power out of this engine before the turbo kicks in.
 

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The biggest issue you're going to run into is the 87 HP 1.4 engine. You need to pull more power out of this engine before the turbo kicks in.
It probably makes about 30 hp down low, lmao.

The turbo is tiny and spools fairly quickly though. The manuals limit boost via ECU tuning down below 2500 RPM, but they start to bring on a decent amount of power around 1800-2000 RPM.
 

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Discussion Starter · #11 ·
Okay - just needed to make sure we knew all the facts...it should not be cutting out there, that's still peak power. Weird...
Exactly, and yea, been running premium since day 1. But it just doesnt make sense to me, and it all depends on the condition and how i accelerate.

I f i start on first gear and and stay on 4K rpms, and slam the gas pedal, exactly at 5200 rpms, you feel a massive cutoff, you hear the exhaust start to sputter, and you feel like you just hit the brakes.
If i replicate the same thing on second gear, it will not cut off so drastically, but you can feel the car suddenly loose power on the same range and struggle to accelerate a little.

But weirdly enough, sometimes on the first gear pull, it will go all the way to 6k without issues.

So on that regard, im at a complete loss.

I think maybe dirty injectors???
Computer cutting off??
Knocking???
Like i said, it happens with both sets of plugs, BKR7E and BKR8EIX
I had the intake manifold issue, but did the Fix provided here.
Gonna try to take a video off what happens, see if that can explain the issue better jejejej.
 

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Exactly, and yea, been running premium since day 1. But it just doesnt make sense to me, and it all depends on the condition and how i accelerate.

I f i start on first gear and and stay on 4K rpms, and slam the gas pedal, exactly at 5200 rpms, you feel a massive cutoff, you hear the exhaust start to sputter, and you feel like you just hit the brakes.
If i replicate the same thing on second gear, it will not cut off so drastically, but you can feel the car suddenly loose power on the same range and struggle to accelerate a little.

But weirdly enough, sometimes on the first gear pull, it will go all the way to 6k without issues.

So on that regard, im at a complete loss.

I think maybe dirty injectors???
Computer cutting off??
Knocking???
Like i said, it happens with both sets of plugs, BKR7E and BKR8EIX
I had the intake manifold issue, but did the Fix provided here.
Gonna try to take a video off what happens, see if that can explain the issue better jejejej.
I'm thinking ignition - coil pack specifically. It's a known weak point (and make sure that your springs are straight when you put it back on the plugs). Mine pulled smoothly to the redline - bounced it off the limiter in 2nd/3rd a few times without realizing it when trying to pass, but power hits a brick wall at 5500 RPM on stock tune/turbo.
 

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Discussion Starter · #13 ·
I'm thinking ignition - coil pack specifically. It's a known weak point (and make sure that your springs are straight when you put it back on the plugs). Mine pulled smoothly to the redline - bounced it off the limiter in 2nd/3rd a few times without realizing it when trying to pass, but power hits a brick wall at 5500 RPM on stock tune/turbo.
Never crossed my mind that it could be the coil, maybe not getting enough current???or its failling..

And thats the same feeling, a brick wall jejejeje

Will pull it out and check the springs just to make sure.

Im also trying to get a Wideband A/F gauge.
I wanna see what is the mix at that point, if fuel is being cut off, or suddenly running rich and chocking the engine maybe?
Or the opposite and suddenly running very lean???
 

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Fuel cutoff feels like hitting a wall, but that's usually only done at your speed limiter.
 

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I was just about to do some research on this, but I figured I would borrow this post as it seems the OP and I are looking at the same things.

What about the actuator? Has anyone researched putting a different one in to holds boost longer? Maybe taking one from a diesel and modifying the bar?

Again, I haven't done the research completely and it may have already been answered somewhere else. Also, I know this would not completely help down low and these tiny turbos can be maxed out pretty quickly. Just a thought.
 

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Discussion Starter · #16 ·
I was just about to do some research on this, but I figured I would borrow this post as it seems the OP and I are looking at the same things.

What about the actuator? Has anyone researched putting a different one in to holds boost longer? Maybe taking one from a diesel and modifying the bar?

Again, I haven't done the research completely and it may have already been answered somewhere else. Also, I know this would not completely help down low and these tiny turbos can be maxed out pretty quickly. Just a thought.
I wouldnt go that route, because if you alter the rod/actuator, your gonna increase boost, but fuel trims will stay the same. It could lead to bad things in my opinion.
But anyone is more than welcome to shed some lights.

But like i said, from my understanding, even, if you did that, (wich it shouldnt be done witout fuel adjustment and tune) i learned that this car is torque manage and will cut boost one the desire torque is reached.

My car for example never hits 15 psi, right now its hitting 9-10.

But this is open for discussion, which is what i like about this forum, everybody contributes to find a answer or solution
 

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I was just about to do some research on this, but I figured I would borrow this post as it seems the OP and I are looking at the same things.

What about the actuator? Has anyone researched putting a different one in to holds boost longer? Maybe taking one from a diesel and modifying the bar?

Again, I haven't done the research completely and it may have already been answered somewhere else. Also, I know this would not completely help down low and these tiny turbos can be maxed out pretty quickly. Just a thought.
Boost is controlled by the ECU, and that is the way it should be. The boost mapping or max torque values can be altered via a tune. Too much boost at low RPM = trashed pistons or bent rods.
 

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Makes sense to me. However, even if you are making the appropriate changes within the tune, you are still limited by the spring within the actuator, correct? Would an individual, that is tuning their car themselves, not be able to set proper values to compensate for the stiffer spring with an upgraded actuator? Conservative tune at low RPMs, ramp at higher RPMs, and maintain a higher max boost.

I guess I don't know the max boost this turbo can produce and if it is even worth it on a factory one. I was getting ready to buy the Vermont Tuning one, but it is no longer made and I am not spending the money BNR wants, since I am going to be tuning with the help of a friend.
 

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Makes sense to me. However, even if you are making the appropriate changes within the tune, you are still limited by the spring within the actuator, correct? Would an individual, that is tuning their car themselves, not be able to set proper values to compensate for the stiffer spring with an upgraded actuator? Conservative tune at low RPMs, ramp at higher RPMs, and maintain a higher max boost.

I guess I don't know the max boost this turbo can produce and if it is even worth it on a factory one. I was getting ready to buy the Vermont Tuning one, but it is no longer made and I am not spending the money BNR wants, since I am going to be tuning with the help of a friend.
The ECU is in full control of the actuator through the turbo control valve...it will hold whatever boost the turbo can produce - upwards of 26 PSI, though that's well past the efficiency window of the turbo (the stock recirculating valve is another matter - for that, I would recommend the Forge BPV).

These aren't 1980's turbo cars anymore that just control boost through vacuum hoses alone.
 

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Discussion Starter · #20 ·
The ECU is in full control of the actuator through the turbo control valve...it will hold whatever boost the turbo can produce - upwards of 26 PSI, though that's well past the efficiency window of the turbo (the stock recirculating valve is another matter - for that, I would recommend the Forge BPV).

These aren't 1980's turbo cars anymore that just control boost through vacuum hoses alone.
You recommend BPV vs BOV??

i know the differences and the tunning required for the BOV, but just wanted to ask?
I know it will hold better boost, but will sound be affected, as will it be heard more if you have an intake?
 
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