I have a -15% and +2 Crank on my ride. I just installed a boost gauge last week. I was seeing 16psi @ redline in 2nd ( I have the MTH tuner as well w/ a redline of 7200) Now a wk later Im seeing around 14psi. It has warmed up considerably and become more humid here in SE Wisc.

I know that ambient temp plays a role and perhaps humidity in the boost generated...from what I have read here.

Question----

what variation of boost do you see and under what atmostpheric conditions....ie...high boost = cold/ dry...low boost =hot /humid...???

Thanks.

 

moderator plz move to performance mods.. for S. sorry

 

Cold dry air gives the highest hp.As soon as ambient temp rises and humidity increases your ability to get boost decreases.Im sure that the technoids will chime in,but in laymans terms,thats what happens.Its all got to do with the density of cold dry air vs hot humid air and its effects on boost and hp.So if you dyno a supercharged car pick a cold dry day for bragging rights.

 

I understand that cold air has a greater density thus a greater boost is created.

guess I should re-word the question...

Im curious what your "normal" range of boost has been....(all mods on the vehicle remaining constant)...and under what astmostspheric conditions....??

For example...."my car got 16 psi when 30F and dry and 12psi when 95F and steamy.....

I understand this will vary widely as weather conditions vary widely across the lands...

Motor on.

 

Wouldn't the car have greater then 16psi before with the 15 and 2%? Or as you said there is variations in cars.

 

ITs cold again TwOMINIs; whats the boost reading today.

 

Cold air is more dense... you can't burn humidity... Also barometric pressure plays a part in this too... Best are those cool morning days when its 50 degrees or so... Too cold and you have no traction... low to mid 50's are great temps to play in...

 

unless you have tires like mine that slide under 60 degrees. I'm in the powerband/tractions dilema.

 

If you have a data logger that measures manifold air pressure, you can get quite accurate readings, esp. when compared to either electrical or mechanical boost gauges. In my car with a 15% SC and 2% crank pulley (effectively a 16.4% pulley), the Defi boost gauge may read 16 psi, while the beta Bim-Com logger usually shows 0.3 to 0.5 psi lower. The calculation does adjust for atmospheric pressure.

 

It's been too wet to see what the boost reading are...damn tires, can't seem to take a bite .