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Old 11-12-2015, 03:32 AM   #1
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Boost

Ok i posted here a couple days ago... but i dont think i was clear on what i meant. My friend has a sr20det s14 thats over boosting at low rpms but doesn't go past what the boost controller it set at. Someone said wastegate but what else can cause this?

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Old 11-12-2015, 04:21 AM   #2
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What do you mean by "overboosting" in low rpms?

But check the usual:
- check if wastegate opens
- check for any leaks
- check if hoses for the boostcontroller are connected properly
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Old 11-12-2015, 08:34 AM   #3
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At like 1000rpm its al ready at 3psi or higher

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Old 11-12-2015, 08:37 AM   #4
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Last time i said boosting to soon and got no help

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Old 11-12-2015, 01:27 PM   #5
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So the boost is starting early is the best way for me to describe it but i thought maybe with saying overboosting i may get someone to understand what im saying. I believe his boost never started building til 2500rpms but now he cant even touch 5mph or 1500rpms without hitting 3.5psi or higher

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Old 11-12-2015, 02:24 PM   #6
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It would help to have more car info. Is the turbo stock, is it stock boost, manual or electric boost controller, electric boost guage or analog boost guage. My guess would be a poor boost vac guage. As it is really hard to build boost that low in the RPM range.

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Old 11-13-2015, 01:32 PM   #7
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My guess is an improper reading - try another gauge or hook up a long vacuum gauge and give it a shot.

If not - it could either be a seized wastegate (unlikely, even at 1K rpm the engine shouldn't be producing enough air to start positive pressure), too small of a turbo, or your ignition timing is severely retarded with a large amount of fuel enrichment (basically unwanted antilag).
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Old 11-13-2015, 02:10 PM   #8
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He feels the added boost but one day it was fine your normal turbo lag then now its no lag at all. I thought it may be a leak by the boost contoller due my civic i had the boost controller broke and i had instant boost but with it the turbo was so big first wouldnt even boost.

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Old 11-13-2015, 04:36 PM   #9
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Quote:
Originally Posted by r.a.ward42 View Post
now its no lag at all.
If you eventually fix this please let me know. I want to break whatever it is that causes this so I can get no lag too.
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Old 11-15-2015, 09:34 PM   #10
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Boost Gauge must be hooked up wrong??? Where is the reading coming from?
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Old 11-15-2015, 09:34 PM   #11
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From the how the car takes off and the boost gauge both

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Old 11-15-2015, 09:37 PM   #12
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Quote:
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From the how the car takes off and the boost gauge both

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Where does the hose on the back of the boost gauge go?
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Old 11-15-2015, 09:47 PM   #13
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That im not sure id have to ask. Its my friends car just was on this site so figured i could get some starting points to help him get it fixed cheaper

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Old 11-16-2015, 12:51 PM   #14
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Thread only makes sense, if you don't understand how stuff work's. Boost gauges reads positive pressure and or vacuum not lag.

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Old 11-16-2015, 01:47 PM   #15
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Im just say its boosting soon not saying its reading lag. There is pressure from the turbo from start not from 2500 rpms or so like it should be. My understanding of lag is the point of where the turbo isn boosting to where its building boost. I may be wrong on the understanding of lag iv only had one turbo car and didn have it very long but all my knowledge of cars is self taught so i can see where i may make say somethin that dont make full sense. And seems like a few people understand what i mean so i cant be to far off from what it is.

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Old 11-16-2015, 03:51 PM   #16
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You need to find out where the hose from the boost gauge is going. We will know more once we find out. At idle, the boost gauge should read vacuum only, when you press the gas pedal and gain rpm's the gauge will lose vacuum pressure and read positive psi (boost) pressure. Lag or not the positive pressure will increase.

Your saying the gauge is reading positive pressure at a high psi (where your boost controller is set) at 1500 rpm's? If it is true then that's good. Most likely your gauge isn't reading correctly or isn't plumbed into the right area.
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Old 11-16-2015, 05:15 PM   #17
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Boost controller is set for 13psi. The boost never read anythin til closer to 3000rpms by at 1500 its already at 3.5 to 4psi and he is feeling his boost pretty much from take off

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