How to make my car not boost?

[StryfeS13]

I have a T25 setup on my KA24DE, and I need it to stay out of boost. I don't have any fuel management as of yet and I don't want it to run lean. Don't ask, I'm waiting for shit to get shipped to my door and it's taking forever cause winter storms on the east coast.

Anyway, can I disconnect my wastegate actuator arm? Hopefully that will cause it to stay out of boost and run like normal?

[z2roll4life7]

Don't drive it man don't risk it

[StryfeS13]

Yeah, it hasn't been driven the last 5 days. No worries. I was just curious if that was possible.

[since87]

Originally Posted by z2roll4life7

Don't drive it man don't risk it

i know your sn from sdrev

[roboticnissan]

Get a boost gauge and watch as you drive?

[gunmetalr32]

take off your turbo... No turbo. No boost!

[RACEBREAD]

ya boost gauge and watch ill bet it hits "A" psi lol

[steve shadows]

Just take the wastegate actuator off. Should work.

[StryfeS13]

I can't just get a boost gauge and observe the boost lol, I don't want it boosting at all. It misses at idle and bogs under normal driving, since it doesn't have enough fuel I'm guessing, so I'm just trying to disable it until I can figure it out.

@ steve shadows, I guess I will try that.

Oh, and tell me if this sounds right people: KA-T with T25, FMIC, etc etc etc, but with no fuel management. When floored it goes vrooooom, then boost hits and it goes blahhhh, and it stutters and won't go into boost.

I'm guessing it's because it has more air than it used to, and now it needs more fuel than it used to have as well. So when I go into boost and it stutters, goes blah, etc, it's cause it's going lean. Correct?

So hopefully when my shit gets here, it'll fix this problem.

[mikerbike]

Sounds like something else is wrong. The engine wouldn't be getting "more air than it's used to" at idle because of a turbocharger. And if you consider putting around under boost 'normal driving', then normal driving with all factory running gear and a small turbocharger won't make it bog. You have other problems, most definitely.

[StryfeS13]

It had no problems before boost, so maybe a possible boost leak???

The PERFECT way to explain it is that when it goes into boost at FULL throttle it's like it's hitting the speed limiter. It just falls on it's face

[UNISA JECS]

Originally Posted by StryfeS13

I have a T25 setup on my KA24DE, and I need it to stay out of boost. I don't have any fuel management as of yet and I don't want it to run lean. Don't ask, I'm waiting for shit to get shipped to my door and it's taking forever cause winter storms on the east coast.

Anyway, can I disconnect my wastegate actuator arm? Hopefully that will cause it to stay out of boost and run like normal?

Disconnecting the wastegate will only make you boost even higher, hopefully you fuel management also allows you to control timing thats where its at for a reliable efficent KA-T.

[guitaraholic]

I agree with mikerbiker, you def have other problems, yes check for a boost leak, your car will run lean before book, then rich while in boost (I believe that is how it is).

If you want no booost, I guess there are couple of ways you can do it.

1. Make the arm on the WG actuator a lot longer (you'll have to mod it, but its pretty easy, just do a search, or you can do what I did (because my WGA stopped working and I was kitting 17psi). I got the HKS adjustable, when I turned it up all the way (full length), I would make like 2psi at FULL THROTTLE at 6000RPM,, I didn't realize how SLOW and SR without boost is.

2. You can get real extreme and just bypass the turbo all together and hook a tube from the make straight into your thottle body. You'll be completely without boost then. Though I would still put some kind of filter over the turbo (don't want crap getting sucked in)

[brndck]

Disconnect the wastegate arm from the flapper. There should be a small c-clip connecting em. Voila, no boost.

[cotbu]

Originally Posted by guitaraholic

2. You can get real extreme and just bypass the turbo all together and hook a OEM like tube from throttle body to AFM. You'll be completely without boost then. Though I would still put some kind of filter over the turbo (don't want crap getting sucked in)

fixed it a little for you.
For this 240 owner, it's probably the safest option period!

[guitaraholic]

Originally Posted by cotbu

fixed it a little for you.
For this 240 owner, it's probably the safest option period!

LOL, I didn't realized I left out MAF and was missing a few other things. I was caught in mid sentance in the middle of work when putting up the post. LOL

After going back and reading mine I was like OOPS...lol.. Thanks for correcting it for me.

[FaLKoN240]

What injectors are you running? What MAF are you running?

[arsenics14]

If you are running stock injectors, and running a blow-through setup (MAF sensor in front of the intake manifold or after the cooler) there is a way...

You could disconnect the cool side pipe from cooler to MAF leading to intake manifold. But I would not drive around like this for a long time unless you have a filter in front of MAF.

Best bet is to wait for your parts to come in and get everything done right 1st time.

[nismoman]

This thread is completely stupid. Get a tuned ecu installed then drive the car or drive it now and blow it up.....

[mikerbike]

Originally Posted by StryfeS13

It had no problems before boost, so maybe a possible boost leak???

The PERFECT way to explain it is that when it goes into boost at FULL throttle it's like it's hitting the speed limiter. It just falls on it's face

Oh. You said it misses at idle and bogs during normal driving, so I thought you meant, "It misses at idle and bogs during normal driving." A leak in your charge piping or pre-turbo intake tube could cause the problems you are describing.

Originally Posted by UNISA JECS

Disconnecting the wastegate will only make you boost even higher,

woahwoahwoah!! Disconnecting the wastegate pressure line will make more boost.

Disconnecting the wastegate actuator from the wastegate flapper (as described in the posts you're trying to discredit) will decrease boost, a lot.

Originally Posted by guitaraholic

2. You can get real extreme and just bypass the turbo all together and hook a tube from the make straight into your thottle body. You'll be completely without boost then. Though I would still put some kind of filter over the turbo (don't want crap getting sucked in)

Bad Idea, IMO. Then the wastegate actuator will never see pressure and never open, sending ALL of the exhaust through the turbine and causing it to spin to the moon. When it's building pressure against the intake tract, it's RPM is being limited. When there's nothing fighting it, my guess is, the turbine or compressor wheel will come apart. Maybe not though. I wouldn't risk it.

[guitaraholic]

Originally Posted by mikerbike

Bad Idea, IMO. Then the wastegate actuator will never see pressure and never open, sending ALL of the exhaust through the turbine and causing it to spin to the moon. When it's building pressure against the intake tract, it's RPM is being limited. When there's nothing fighting it, my guess is, the turbine or compressor wheel will come apart. Maybe not though. I wouldn't risk it.

You do make a good point, maybe combining the two ideas would give you the best result for "zero" boost. If you disconnect the WGA and bypass the turbo, you will have no pressure on the turbo to build boost, and being you are not building boost, you are not going to have as much exhaust pressure to spin the turbo. (wastegate is open with the slightest amount of exhaust pressure), and well you would bypassing the turbo all together with connecting an OEM style tube from the MAF to the Thottle body.

Though this is all a lot of effort to run zero boost. Maybe best idea not to drive it, or put back on the OEM setup until all the stuff arrives.

[cotbu]

He's over thinking the idea, If there are no charge pipes connected, there would be no boost to build, "NO BOOST TO BUILD" even if the wastegate was still connected. again the compressor outlet to hot pipe would have to be connected in someway to the throttle body.
As long as the little T2 had oil and water it could run this way forever!

Originally Posted by guitaraholic

You do make a good point, maybe combining the two ideas would give you the best result for "zero" boost. If you disconnect the WGA and bypass the turbo, you will have no pressure on the turbo to build boost, and being you are not building boost, you are not going to have as much exhaust pressure to spin the turbo. (wastegate is open with the slightest amount of exhaust pressure), and well you would bypassing the turbo all together with connecting an OEM style tube from the MAF to the Thottle body.

Though this is all a lot of effort to run zero boost. Maybe best idea not to drive it, or put back on the OEM setup until all the stuff arrives.

[mikerbike]

Originally Posted by cotbu

He's over thinking the idea, If there are no charge pipes connected, there would be no boost to build, "NO BOOST TO BUILD" even if the wastegate was still connected. again the compressor outlet to hot pipe would have to be connected in someway to the throttle body.
As long as the little T2 had oil and water it could run this way forever!

Indeed, no boost to build, meaning the turbo would be allowed to spin faster than ANY situation where it would build boost.

And if you "connected in some way" the "compressor outlet to hot pipe to the throttle body", wouldn't it be like normal? Sending compressed air from the compressor outlet to the throttle body? Were you high when you wrote that?

[cotbu]

I was answering the OP's initial question. No boost. Now regarding the spinning of the Turbo, if the wastegate was still connected or not, its going to spin. agree? never being able to make boost is the outcome. I don't really know what you're getting at. Disconnecting the flapper isn't going to stop the turbine from spinning uncontrollably. Either way is a no boost answer to his question.
And yeah, I'm a little tipsy and its a new years after after party.


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[steve shadows]

Originally Posted by UNISA JECS

Disconnecting the wastegate will only make you boost even higher, hopefully you fuel management also allows you to control timing thats where its at for a reliable efficent KA-T.

NOT the vacuum line, the actual whole unit.

If the flap door is open it shouldnt boost at all or maybe only 1-2 psi.

The flap door having tension and being closed is what creates build up of exhaust pressure which creates boost on the compressor side.

If you just take off the vacuum line to the actuator you are correct though

gotta take the arm off the door, other than that it's a mechancal ssystem, you would have to remove the turbo to remove the possibilty of any positve pressure at all

[UNISA JECS]

Obviously I meant the pressure line going to the wastegate actuator, but yea you should disconnect the actuator rod from the wastegate flapper.

[mikerbike]

Originally Posted by cotbu

Disconnecting the flapper isn't going to stop the turbine from spinning uncontrollably.

False. The reason the flapper is pushed open by the wastegate actuator is to CONTROL the speed of the turbine/compressor. I'm sure the flapper will be pushed open at idle if it's not connected. Sure, the turbo will spin, but not enough to build any boost against the charge piping/intake tract.

[UNISA JECS]

Originally Posted by mikerbike

False. The reason the flapper is pushed open by the wastegate actuator is to CONTROL the speed of the turbine/compressor. I'm sure the flapper will be pushed open at idle if it's not connected. Sure, the turbo will spin, but not enough to build any boost against the charge piping/intake tract.

Whats false about what he said its true. I doubt the flapper would even open at idle, at idle you can take yoru finger and stop the compressor wheel instantly. It will build some boost even with the flapper disconnected cause believe it or not the exit of the exhaust is still somewhat restricted and will spin the turbine fast enought to build a pound to two of boost.

[mikerbike]

He said 'uncontrollably'. The reason the wastegate is there is to 'control' the speed of the turbine/compressor. And the exahust flow isn't the only thing regulating the speed.

I've never disconnected my flapper from the actuator to see if it is open at idle, so I could be wrong. But it doesn't take much to swing 3 ounces of metal on a <1" fulcrum.

I had a small T3 on a KA a long time ago, with the flapper assembly removed completely, and the turbo wasn't spinning at idle. I didn't drive it around like that to see how much boost it made in the upper RPM though. But I'm sure, positive, that unless I was using high throttle/high RPM, it wouldn't boost. Positively sure.

If it's warm this weekend, I'll disconnect the actuator from the flapper on my SR, just to see, and report back my findings.

[godrifttoday]

Just don't connect an intercooler pipe that's all