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Acura EL
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Discussion Starter #1
So as some of you may know, a couple months back i had posted a thread on my turbo's shaft play. It turns out it was infact blown..It has been rebuilt since then but there's a new problem here. today i went to have some fun on a straight away near me and my car had hit boost cut pretty badly in the 6000-7000rpm range in 3rd (havent tried other gears to see if it does it in them aswell). The thing thats weird is that its the exact same turbo but everything, and i mean everything, has been replaced in it..Ive already had it on the car for around 400km for the break in stage and the weather at the time of the pull was pretty normal (25-27 degrees Celsius)


my questions are: is it a tuning issue? Do i need to get the car retuned?

could it be something else?
 

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ej8
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6,365 Posts
Not enough information.

What was your boost pressure before the rebuild?
How are you controlling boost? (mbc, ebc, wg spring)
What is your boost cut set too and did you get to that psi or did it just feel like boost cut kick in?


Its possible you didnt put everything back as before.
There could of been a boost leak before you took everything apart.
The turbo with the shaft play could of been lagging and not making full boost.
Could be a few things
 

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Classic Man
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Sounds like ur turbo is more efficient now, since it been rebuilt. Or maybe you fixed a small pre turbo exhaust leak or boost leak, and now its slightly more efficient and makes a few psi more boost.


I would either turn the boost down a little or get it retuned.
 

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Acura EL
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Discussion Starter #5
Not enough information.

What was your boost pressure before the rebuild?
How are you controlling boost? (mbc, ebc, wg spring)
What is your boost cut set too and did you get to that psi or did it just feel like boost cut kick in?


Its possible you didnt put everything back as before.
There could of been a boost leak before you took everything apart.
The turbo with the shaft play could of been lagging and not making full boost.
Could be a few things
i was at 15psi before, now only 10.
its an electronic boost controller
i definitely did not reach anywhere near that on the pull. It only reached around 9-10 when it cut, and when it did a big flame came out the side and the engine light came on for a split second..
 

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ej8
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i was at 15psi before, now only 10.
its an electronic boost controller
i definitely did not reach anywhere near that on the pull. It only reached around 9-10 when it cut, and when it did a big flame came out the side and the engine light came on for a split second..
What was the AFR leading up to the cut?
Most EBC drop the psi to spring pressure when they cut. What is your spring psi or boost controller 0 duty% psi?
Also are you saying the boost cut was 15psi and you lower it to 10psi and you end hitting the cut?
And what psi was it tune for?

And the flame sounds like you have to much timing pull in the tune.
 

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How big is your wastegate's spring? I've had an issue in the past where a bad boost controller caused a nasty boost cut. Have you tried running straight wastegate pressure to see if it still cuts?
 

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Acura EL
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Discussion Starter #8 (Edited)
i was at 15psi before, now only 10.
its an electronic boost controller
i definitely did not reach anywhere near that on the pull. It only reached around 9-10 when it cut, and when it did a big flame came out the side and the engine light came on for a split second..
What was the AFR leading up to the cut?
Most EBC drop the psi to spring pressure when they cut. What is your spring psi or boost controller 0 duty% psi?
Also are you saying the boost cut was 15psi and you lower it to 10psi and you end hitting the cut?
And what psi was it tune for?

And the flame sounds like you have to much timing pull in the tune.
I'll be honest with you, I don't know much about what you're talking about. It vacuums at 20 psi if that's what you are asking

Also the turbo does go to 20 psi just like the old turbo, It just needed a break in. The car is tuned for 20 to my knowledge.

The AFR is close to rich when it happens aswell
 

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97 honda coupe
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if you take the top port off of the wastegate and go for a cautious run, see if it still hits boost cut. the computer is mapped for a shitty turbo that isnt generating boost efficiently and the duty cycle is probably too high on the top end. so if you take the top port off and slowly build boost it shouldnt hit boost cut on you. however if it does still hit the boost cut then you might have another problem such as afr's going above a setpoint.
 
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