I have a 99 gst, and was wondering what the proper vacume is you should get. i have an aftermarket gauge and it usually reads about 19. the reason is im asking this is because my friend has a gsx and his always reads around 10. just curious which is correct.

 

19 is right... something is up with his car

 

yeah mine is the one thats reading 10, i think my gauge isn't sealed well enough, i'm gonna take it off and seal the hell out of it, but at least i got all my other vacuum leaks sealed off

 

-19 to -21 is what your vacuum should be at. Mine is at -20 to -21 usually.

 

depends on elevation but yea in san diego sea level i had a 750rpm idle, -19 vacuum at idle, and -24ish vacuum during decelleration.
-10 sounds like a leak

 

I'll have to look at mine again but I get a bit more than -24 on decel, don't know why, but I do.
..and yeah, 18-20hg is right.

 

i leak and i'll still tear your car up bestwiseguy lol

 

ha ha F**** YOU. jk. hey at least my rim has never fallen off.

 

lol, "vacume" lmao... Mine reads -20. -10 would be a considerable leak.

 

mine reads -20 too....lol dusty