factory boost psi

[ilplumber]

Installed SPA boost gauge. Zeroed the gauge then started the truck and went for a drive. At full throttle I maxed out at 7 psi boost. Is this normal for a factory 2001 auto turbo? Seems a little low to me. Thanks!

 

[mediccummin]

NO

You should be getting around 18-20 stock. You might need to go back through and check for leaks in your tubing. Good luck... ... ...

 

[LSMITH]

SPA has no tubing, it is possible to have a leak at the fitting, but not enough to get you down to 7 PSI. The truck would be a miserable gutless pig at that boost max. Do you have access to a digital camera? I have been following this from the 911 post this morning and am not sure you are in the right port. You should be getting 18-20, the peak recall feature on the SPA (the ushbutton) should show 20-21 PSI. You should be able to sustain 18 PSI through the gears. Something is not right. Is there any more info you can give to help us help you?

 

[barryg41]

I had a hard time getting my boost to read right the first time. I had to take the boost transducer apart and reconnect it again to the plug. I sprayed it with brake cleaner to make sure it didnt have any trash or oil on it. Did the trick for me!



I had to to do it again after about 4 months to get it right again. There is a grease for this problem... . someone spell it out for me.



I always got 19 lbs. stock and 31 with PE EZ.

 

[DHarvey]

Hmmmm... . I've got the EZ box, but have never gotten over 24psi and that's under heavy load WOT. I use the turnbuckle too to delay the actuator. Stock it would peak at 21psi. Think something could be wrong here?

 

[KatDiesel]

Originally posted by DHarvey

I use the turnbuckle too to delay the actuator.

Do you have the turnbuckle in far enough to effect the wastegate? If you do, then next I would look at your gauge and see if its accurate.

 

[ilplumber]

I will remove clean and replace it. I put it in the 3/4" hole by the fuel filter. Slightly to the right of it when standing on the drivers side of the truck. truck seems to run normally.

 

[DHarvey]

KatDiesel wrote...

<<Do you have the turnbuckle in far enough to effect the wastegate? If you do, then next I would look at your gauge and see if its accurate. >>



I have the spring on the end of the turnbuckle and the turnbuckle is adjusted to minimum length, causing the spring to be stretched ~twice it's original length. It should be causing strong resistance to the actuator... maybe not enough?



I don't suspect the guage as it always seemed to indicate correctly with no bombing.

 

[JR2]

iplumber - go back to the 911 section and get Brandons phone # that he posted. Call him, he will get it working correctly. He is "the man" when it comes to SPA gauges. He has installed hundreds of them.



JR



Any luck on the thermocuople??

 

[ilplumber]

I set the boost range @ 60 bar this morning. I got 17 lbs. boost at WOT. I thought it should be at 16 bar. Hooked 50 psi air directly to sender and got almost 50 psi on gauge in 60 bar range. So i assume this is the setting for me to use? I will call my supplier tomorrow and have them send me the correct thermocouple and yellow plugs. The gauge does not zero every time i turn the key on? I zero it drive 2 miles and shut the truck off. turn the key back on 10 minutes later i read +2 psi and sometime -2 psi without the truck running. With the gauge zeroed and truck idling i get 2 psi boost. Such an expensive gauge should be more user friendly. I'm not a rocket scientest by any means but i don't think i'm as dumb as this gauge makes me feel. If I have no luck with the supplier tomorow I will definetely call Brandon. Thanks for your help in my ongoing saga. Silly me thought it was a 2 hour project. Still a cakewalk compared to working on the vette. That long valve cover makes a pretty good seat.



ILplumber

 

[JR2]

Iplumber- I have the same problem with the the zero. From the best I can tell it is most definitly temp sensitive and it has alot to do with the range of the sensor (0-250 psi). I mounted a small power switch on the back of my gauge pod so I can zero the gauge with out turning the truck off and back on. My fuel press gauge does the same thing. I agree that the gauge should be a bit more stable. If SPA would come out with a pressure sensor that had a bit smaller range it would help too... nothing like using a 0-250 psi sensor to measure 12 psi fuel press or 35 psi of boost. 0 to 100 psi would work fine. I have access to some other brands of sensors and was thinging about playing around with different sensors when I have time. The problem is the sensors are about $200.

 

[LSMITH]

I have had the SPA for a long time and have not had any trouble maintaining zero. With temperature changes the density altitude will change. This effectively changes the atmospheric pressure, which is the reference pressure that is used to set your zero point on the guage. High and low pressure systems moving into and out of your area also affect it in the same way. That said, I still do not have trouble. I reset my zero once a month or a little less. It might be off a pound and sometimes two, but will come back to the seasonal mean for your area within a day or two. This is not unique to the SPA or to digital guages in general, it affects the analog guages the same way and by the same amount, you just can't see it on the analog guages. With the resolution of the SPA you are not going to get around the zero wandering slightly, it is not the range of the sensor. For the resolution and accuracy (both are overkill, but I like it) I will gladly put up with this "problem" on my guage. Hope this helps clear up some of the confusion.

 

[mediccummin]

oops

I should of read a little closer, He has the SPA my fault, foot in my mouth... ...

 

[Cumminpwr11]

stupid question time







What is WOT?

 

[speedracer]

WOT = Wide Open Throttle (even though we technically don't have throttles)