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I was hoping you could answer a few questions for me? 1) What should the compression be after a test on all four cylinders? 2) when installing a mechanical dual stage boost controller I was told one of the lines from either the pressure source or the wastegate has to be plugged off and you use another vacuum source? is that true?
3) Why does the boost on second stage only reach 20 lbs. in first, second and fifth gear? shouldn’t be 20 lbs. in all gears if that is where I have it set? 4) would my B.O.V. have any effect on the boost? All help would be greatly appreciated as I live in Reno Nevada there are no real authorities on dsm's or evo's here PLEASE HELP with any answers you can give me.
 

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renoevo8 said:
I was hoping you could answer a few questions for me? 1) What should the compression be after a test on all four cylinders? 2) when installing a mechanical dual stage boost controller I was told one of the lines from either the pressure source or the wastegate has to be plugged off and you use another vacuum source? is that true?
3) Why does the boost on second stage only reach 20 lbs. in first, second and fifth gear? shouldn’t be 20 lbs. in all gears if that is where I have it set? 4) would my B.O.V. have any effect on the boost? All help would be greatly appreciated as I live in Reno Nevada there are no real authorities on dsm's or evo's here PLEASE HELP with any answers you can give me.

1) I have never done a compression check on my car. If you purchased a gauge from sears just take it back.... I have used two of those in the past, and both of them were F'ed up.
The main thing you are looking for on a compression check is that the numbers from one cylinder to the next are consistant.... if one is ready way off from the other three then you have a problem.

2) If you still have the stock outlet tube on your turbo with the boost nipple on it, that is your best boost source for a manual boost controler. If you do NOT have that nipple any more, use a "T" in the BOV line as your boost source. So you end up with one boost source line to the MBC, one boost line going from the MBC to the wastegate actuator, and a bunch of extra lines connected to the stock solenoid. Leave the solenoid plugged in to the wire harness and don't worry about it any more... I have no idea why people think it needs plugs over the nipples... it isn't connected to anything anymore. You will have an un-used nipple on the stock intake tube that needs to be capped over.

SAVE YOUR STOCK BOOST LINES, T's, AND RESTRICTOR PILLS!!! If you ever want to put the car back to stock and sell it you will need them.

3) You need to clarify this question, I have no idea what you are talking about.

Keith
 

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1) Agree with Fourdoor that the main thing is that all 4 cylinders check out the same or within 10psi of each other.

2) No need to specify a mechanical dual whatever. No need for such a thing anyway, and if you have a TXS MBC, you should probably change it for a good one like the Hallman or Forge. Regardless, any MBC you have should just tap into one of the two pressure sources: turbo nipple or BOV line. I prefer the turbo nipple, but both work.

3) What? With an MBC, boost should increase in each successive gear, because there is more load. It would not make sense for 1st, 2nd, and 5th all to reach a peak of 20psi. 1st and 2nd should be lower while 5th should be the highest. 3rd and 4th are proggressively higher than 1st and 2nd...

4) BOV can affect many things. What type of BOV do you have?
 

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renoevo8 said:
1) What should the compression be after a test on all four cylinders?
Engine coolant temperature: 80 − 95°C (176 − 203°F)
Lights, and all accessories: OFF
Crank the engine with the throttle valve fully open and measure the compression pressure.
Standard value (at engine speed of 250 r/min): 163 psi
Minimum limit (at engine speed of 250 r/min): 138 psi


renoevo8 said:
2) when installing a mechanical dual stage boost controller I was told one of the lines from either the pressure source or the wastegate has to be plugged off and you use another vacuum source? is that true?
Fourdoor is right, if your using a new source for the boost controller, you would cap the old boost source that comes off the compressor outlet pipe, but not the wastegate.

renoevo8 said:
3) Why does the boost on second stage only reach 20 lbs. in first, second and fifth gear? shouldn’t be 20 lbs. in all gears if that is where I have it set?
Use third gear to set boost.

renoevo8 said:
4) would my B.O.V. have any effect on the boost?
It could; if you still have the stock BOV, it has a dentency to leak at around 19psi.
Update your car's profile so we can see all you upgrades. :thumb:
 
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