Thread: normal stock compression
10-31-2009, 07:11 PM #1
normal stock compression
on a slightly warm engine run 5 mins and then each cyl. tested, i ran , 115, 115, 115. happy that all #s were exactly the same , but some what low???, the compression tester i have has adapters, the male one going in the spark plug treads fine but the othe female end going into the male end of compression hose does'nt really thread , slightly wrong size, maybe leaking air slightly, are these #s low for stock?
10-31-2009, 07:14 PM #2
10-31-2009, 07:50 PM #3
mike , a real cheap one, like a ebay store , if i remember, i think i need the correct adapter, why?, do those #s sound low?, should'nt i be running 125-130 psi?
10-31-2009, 07:55 PM #4
EFI PV motors are usually 115-120ish
EFI non-pv are usually 130-135ish
all EFIs are a few psi lower on #3
could just be the gauge
when checking compression:
-make sure the PVs are closed/down (when applicable)
-leave the other 2 spark plugs in
-open the throttle
-make sure you have a good charge on the battery
10-31-2009, 08:10 PM #5
rich,all that is done,im going to sears to get a new one, but i'm going to have to test it on the new milled heads, i expect to "bend that dial" all the way back!
10-31-2009, 08:17 PM #6
just so they are all pretty consistant, you are golden!
11-02-2009, 07:12 PM #7
115 for a PV EFI motor!? I have really high stock compression, maybe I'll leave it that way, who has the fastest stock compression gpr?
11-02-2009, 08:12 PM #8
- Join Date
- Oct 2005
11-02-2009, 09:57 PM #9
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