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Boost question

xaisomboun

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Joined
Jun 19, 2011
Messages
117
Location
Minnesota
313 checkin in here with a boost question!

So I used to have it set around 15 psi and when I would go WOT in 2nd or anything, it would jump to 19, almost 20 psi before settling back down to 15 evenly.

Is this normal?? Is this bad?? How can I stop it from happening?

Just as a precaution before I blow anything up, I set it back down to 10 psi and it only jumps like half a psi before settling down to 10.
 

turbowop

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Apr 29, 2001
Messages
11,971
Location
Yakima, WA
No. Boost creep is when the boost stops at the set level, but then creeps upward as the RPM's go up. If you aren't 100% of the answer, please don't post misinformation. You just confuse people.

What you have is just a boost spike. I find that I get less spike when tapping an intercooler pipe or the compressor housing of the turbo as a pressure source for the boost controller, and see a larger spike when tapping the intake manifold or a line off of it, like the BOV line. It is also dependent on the boost controller you use.
 
Last edited:

Brunoboy

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Apr 25, 2008
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2,880
Location
San Bruno,CA Home of SFO
my mistake wop, i meant to say spike....I posted it while at a local coffee shop.
 

xaisomboun

Well-known member
Joined
Jun 19, 2011
Messages
117
Location
Minnesota
Quoting turbowop:
No. Boost creep is when the boost stops at the set level, but then creeps upward as the RPM's go up. If you aren't 100% of the answer, please don't post misinformation. You just confuse people.

What you have is just a boost spike. I find that I get less spike when tapping an intercooler pipe or the compressor housing of the turbo as a pressure source for the boost controller, and see a larger spike when tapping the intake manifold or a line off of it, like the BOV line. It is also dependent on the boost controller you use.



If I tapped off the intercooler piping, would I just swap sources from the BOV and Boost guage? I have the garage mod done to my BOV.
Also the manual boost controller I use is some no name brand my friend got me as a present. This could also be a likely cause right?
 

LIV4PSI

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Joined
Nov 24, 2011
Messages
1,762
Location
O-H-I-O
Quoting brunoboy:
Boost creep



Turbowop is right, it is a boost spike. Here is an excellent video for anyone who has 8 minutes to spare

click

OP, a better boost controller can't be a bad idea. They are rather simple in design, but I have seen some horribly made cheap ones.
 

Brunoboy

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Apr 25, 2008
Messages
2,880
Location
San Bruno,CA Home of SFO
I know hes right...I was in a rush to post....
 

turbowop

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Apr 29, 2001
Messages
11,971
Location
Yakima, WA
Sorry if I sounded harsh. It seems as if there have been a lot of posts like that lately, which bugs the sh*t out of me. If it was just a smartphone whoops I posted something I didn't mean to, than so be it. /ubbthreads/images/graemlins/wink.gif
 

turbowop

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Joined
Apr 29, 2001
Messages
11,971
Location
Yakima, WA
Quoting xaisomboun:
Quoting turbowop:
No. Boost creep is when the boost stops at the set level, but then creeps upward as the RPM's go up. If you aren't 100% of the answer, please don't post misinformation. You just confuse people.

What you have is just a boost spike. I find that I get less spike when tapping an intercooler pipe or the compressor housing of the turbo as a pressure source for the boost controller, and see a larger spike when tapping the intake manifold or a line off of it, like the BOV line. It is also dependent on the boost controller you use.



If I tapped off the intercooler piping, would I just swap sources from the BOV and Boost guage? I have the garage mod done to my BOV.
Also the manual boost controller I use is some no name brand my friend got me as a present. This could also be a likely cause right?



The BOV and gauge are probably sourced from the intake manifold since both need to see vacuum as well (if you have a boost gauge that reads vacuum that is). You boost controller only needs to see boost pressure. If you want to tap an intercooler pipe, you will need to install a nipple or find an existing one to use somewhere on the piping. On 503 I use one off the turbo outlet, and on 1051 I tapped and threaded the upper intercooler pipe for a nipple.

The boost controller that came with 503 when I bought it was a pile of sh*t made from Home Depot parts. It would spike like 10psi. /ubbthreads/images/graemlins/rofl.gif I installed a $50 Hallman unit and it only spikes about 3psi with it tapped off the compressor outlet. Works great.
 

Brunoboy

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Joined
Apr 25, 2008
Messages
2,880
Location
San Bruno,CA Home of SFO
Quoting turbowop:
Sorry if I sounded harsh. It seems as if there have been a lot of posts like that lately, which bugs the sh*t out of me. If it was just a smartphone whoops I posted something I didn't mean to, than so be it. /ubbthreads/images/graemlins/wink.gif


I know what you mean. All good wop , you know I've been on here long enough to know better.
-shane
 

MellowVR4

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Joined
Jul 25, 2009
Messages
1,662
Location
Milwaukee, Wi
i fixed my spiking problem with the lower shore mbc, ported the exh housing and waste gate hole, 34mm flapper and ported the o2 housing. Also i tapped the j pipe for the pressure source that i needed. needle does not move after it hits it set point. lower shores mbc works great, gotta give it to them.
 

xaisomboun

Well-known member
Joined
Jun 19, 2011
Messages
117
Location
Minnesota
Quoting MellowVR4:
i fixed my spiking problem with the lower shore mbc, ported the exh housing and waste gate hole, 34mm flapper and ported the o2 housing. Also i tapped the j pipe for the pressure source that i needed. needle does not move after it hits it set point. lower shores mbc works great, gotta give it to them.



Question, where can I get a LSP boost controller?? Ive googled all over to no avail..
 
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