Vacuum/Boost data:

PFS PMC handheld controller shows -23 lbs at idle.
Autometer gauge shows -17.

PFS PMC shows 10 lbs at WOT
Autometer gauge shows 13.

Which should I trust? Autometer gauge is basic vacuum line gauge to UIM. Can anyone offer an explanation for the discrepancy? Thanks

 

Do a search for "autometer boost gauge"
That should answer your question.


-Ted

 

i searched for that exactly, found nothing that stood out. just some people mentioning their autometer boost gauge in their setups.

 

Oops, you're right - sorry for the too general a search.
Try keywords: "autometer boost accura*"


-Ted

 

https://www.rx7club.com/forum/showth...threadid=59745

actually while searching around, it confirmed what i've always felt. autometer makes fine stuff.

you hear so much bad stuff around them for a few trully silly reasons.

"the quality is low" - well they have several lines of guages each in a different price braket, so buying a 20$ used boost guage is not a good representation of the 50$ new one they make.

"mine didn't set to zero with engine off" - well if it's a tiny ammount and you are not anywhere near see level, it is due to a change in ambiant air pressure. this also changes day to day based on weather conditions. if it is a psi or more then you obviously got a bad guage that either slipped out of the manufacture or got banged up in shipping (these are delicate instruments, not footballs for UPS).

ambiant pressure changes are why most lines of autometer guages do not center on "0", but it's normally a bit less than a psi difference. any guage that does not automatically correct itself EVERY DAY to zero, is being forced to show YOU zero when the engine is off. so don't take it as what you are getting for 100$ more than the average autometer.

if you have a question, consider the changes in ambient air pressure and then call AM's tech support, they will probably try and help you sort it out. you can also buy a pressure pump and hook it into the guage, pump it to a certain presure and verify the guages pressure.

 

There is a ton on this issue in the Power FC section. Chuck did some extensive testing and comparisions. Make sure when you do the search to set the "search from" parameter to "the beginning".

 

It's funny that all of the VDO, HKS, GReddy / Trust, A'PEXi, Omori, and Defi boost gauges do not have this problem fluctuating "0"...



-Ted

 

i don't see it as a problem. maybe all the japanese manufacturers just like to force a 0 reading. it makes perfect sense for it to have a very slight fluctuation.