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Roush 9 PSI?

  • Thread starter Thread starter ximportdriver
  • Start date Start date Aug 3, 2007

ximportdriver

20+ Year Stangneter
Oct 7, 2003
386
46
59
Rancho Cordova
Aug 3, 2007
#1
  • Aug 3, 2007
  • #1
I have a 99 S281 supercharged, and I thought it was not supposed to give any more than 8 PSI, but today it registered 9; is this good or bad?

last weekend I cleaned the MAF, IAC and throttle body - not sure if that matters
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,015
1,612
194
NJ
Aug 4, 2007
#2
  • Aug 4, 2007
  • #2
boost readings on a boost gauge aren't always that accurate.
 

ximportdriver

20+ Year Stangneter
Oct 7, 2003
386
46
59
Rancho Cordova
Aug 4, 2007
#3
  • Aug 4, 2007
  • #3
2000xp8 said:
boost readings on a boost gauge aren't always that accurate.
Click to expand...

i didn't know that, thanks
 

2000xp8

SN Certified Technician
Aug 8, 2003
8,015
1,612
194
NJ
Aug 4, 2007
#4
  • Aug 4, 2007
  • #4
Not saying yours is inaccurate, becuase depending on variables, you very well could of seen a real 9psi.
It's just that my buddy owns a shop, and they hook up the boost to the dyno equipment, and not always is it the same as what the car owner says the gauge is always telling them.
 

ximportdriver

20+ Year Stangneter
Oct 7, 2003
386
46
59
Rancho Cordova
Aug 4, 2007
#5
  • Aug 4, 2007
  • #5
2000xp8 said:
Not saying yours is inaccurate, becuase depending on variables, you very well could of seen a real 9psi.
It's just that my buddy owns a shop, and they hook up the boost to the dyno equipment, and not always is it the same as what the car owner says the gauge is always telling them.
Click to expand...

that's good information to be aware of
 

gonen20

New Member
Jan 27, 2006
195
0
0
Aug 5, 2007
#6
  • Aug 5, 2007
  • #6
When I first got my S281SC it was putting out 12 PSI Boost with out Really getting on it!!! I thought this was really strange, till I noticed my Intercooler temp gauge was showing it was running very hot! My Intercooler Hoses were booth Clogged and nothing was cooling the blower like I told you in another thread!! I'm not sure why that would raise the boost in my guage and blower but it really did!!! I kick myself for not taking a picture of the gauge with that boost measurement showing, no one has believed me of this! Also, the boost would come on instantly back then, Since then I've fixed the problem and I'm lucky if I see 7 PSI out of my boost gauge and in order to get into the boost I really have to put my foot in it!! Whats interesting about an automatic S281SC is that, when I'm into it and the car is automatically shifting the boost stays up and drops very little boost through the shifts! All I need are some better gears and better tires to hook up!
 

marcus95

Active Member
Jan 26, 2004
2,133
0
46
California
Aug 5, 2007
#7
  • Aug 5, 2007
  • #7
Ahh Todd.

You know you are full of shi*.


Only kidding. It's nice to know those temps are super low now huh?

That is a strange one though. Your boos reading 12 psi with the stock pulley? Hey, we have seen much stranger things.



As to the thread starter. I have seen the Saleen guages read off by up to 5 psi of boost so I wouldn't worry about it. Your gauge could be reading correct also as a slight ambient temperature change will give you more or less boost. Overall, your car should make maybe 1 psi more boost when it's cold in the morning.
 

ximportdriver

20+ Year Stangneter
Oct 7, 2003
386
46
59
Rancho Cordova
Aug 5, 2007
#8
  • Aug 5, 2007
  • #8
marcus95 said:
Ahh Todd.

You know you are full of shi*.


Only kidding. It's nice to know those temps are super low now huh?

That is a strange one though. Your boos reading 12 psi with the stock pulley? Hey, we have seen much stranger things.



As to the thread starter. I have seen the Saleen guages read off by up to 5 psi of boost so I wouldn't worry about it. Your gauge could be reading correct also as a slight ambient temperature change will give you more or less boost. Overall, your car should make maybe 1 psi more boost when it's cold in the morning.
Click to expand...

what's interesting--and baffling--is that when i saw the extra 1 psi on the gauge it was in 100 F weather in the afternoon around 4 pm; i don't see 9 psi in the morning
 
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