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Discussion Starter · #1 ·
Hey guys
I just installed my boost gauge this past weekend. I am wondering if i am getting correct readings.

Idle: is around 16-18 mm Hg vacuum

Normal driving/cruising (holding speed constant): 10 mm Hg vacuum

Hard acceleration seems to be right boost levels, 1st and 2nd gear around 10psi and higher boost in 3-5 gears (up to 15psi).

Downshifting: goes down to 20 mm Hg vacuum.

Do these values seem right? are they similar to what you guys get? Also, what is boost spike and boost creep and how do i identify them on my boost gauge?
Thanks for your feedback.
 

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I think they seem in the normal range- My guage read 17 under hard acceleration in 2nd gear yeasterday- hadn't seen that before!
 

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Discussion Starter · #3 ·
Did it stay at 17psi the entire time? or did it settle down to a lower number. If it peaked at 17psi and settles down to a lower number is that boost spike? Thats what i was wondering....how to read boost spike on a boost gauge.
 

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It just hit 17 and went down to 15, then 13 (normal on my car for WOT)- I don't know if that's a boost spike- I thought it might have been related to the cold weather we've been having- I tried to reproduce the 17, but to no avail.
 

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The vacuum readings are similar to mine.

i installed my gauge recently too. Strangely, I get almost 15 psi on all my gears. As far as I know, it's not a spike because It holds and I can repeat it anytime (at WOT). It's never past 15 psi. On partial throttle, I get about 7-10 psi in 1st and 2nd.

ofcourse most people seem to agree this is irregular. I'm stock btw.
 

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I guess a good way to differentiate between regular boost and a spike for someone new would be the following:

We know we're suppose to get 14-15 psi in 4th and 5th, so however your particular gauge performs in 4th and 5th when achieving 14-15 psi, should be considered a normal boost and reading. With that in mind, compare the gauge readings in the other gears to the norm. If the needle is more eradict or fades much quicker, than it's probably a spike.

Also, an unreproduceable reading should generally be considered a spike. Car and gauge should perform consistently unless you have a bad gauge or...a bad car :(

I consider myself fortunate to have a stock car without boost limits in the early gears. That said, I can't expect much gains from a Boost controller, so it'll take more mods to get a gigger kick.
 

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boost --RE : siliver bullet

i have the same problem...

1st 2nd 3rd gear you work up ur boost which may spike sometimes

on 4th and 5th pressure already is rounded up giving you higher boost readings when u accelerate

do you have a boost controller ? i sugguest an electronic one like mine APEXi to control boost at each gear to prevent spikes and overboostin
 

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mine's been reading 13.9 psi max....and that's only 3-5th gear, in 1 and 2......i only managed bout 10.....i've spiked to 15, but that's a spike, so that don't count
 

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boost

sounds like you may have a boost leak...

double check ur hoses to the gauge, where do u live, boost tends to vary in high altitudes..

if it holds and stays @ 13.9 than its fine.. if it goes from 13.9 to 10 then u have a leak
 
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