Stock compression pressure for a NA8?

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Li7hium
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Stock compression pressure for a NA8?

Postby Li7hium » Tue Mar 25, 2008 5:45 pm

Hey guys,

Had a compression test today as Lara is starting to blow a bit of blue smoke.

Just wondering what the stock compression rates are.

Lara went

1. 162 psi
2. 157 psi
3. 161 psi
4. 163 psi

I'm thinking a 6 psi spread over the 4 cyclinders isn't bad, but if all four have dropped pressure, then maybe it is time for the engine overhaul.

Matt
NA8
Wakefield 1:14:78 28-6-09! Oran Park GP 1:27:73 30-03-08 Oran Park South 54:50 14-10-2007 Eastern Creek 2:02:44 6-8-07
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manga_blue
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Postby manga_blue » Tue Mar 25, 2008 5:59 pm

Mine were all 175-180 last week on an NA8 with 165ks. No smoke, but used a litre of oil at Winton on Sunday.

I'd try another gauge or two first before committing to overhaul.
’95 NA8

Babalouie
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Postby Babalouie » Tue Mar 25, 2008 6:27 pm

Factory manual says the range is 192psi(new) to 135psi(shagged). So 160psi is pretty much right in the middle of the range...
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ampz
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Postby ampz » Tue Mar 25, 2008 9:03 pm

so you have another 30 psi of shagging to go :lol:
Huh?

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Li7hium
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Postby Li7hium » Wed Mar 26, 2008 9:03 am

Thanks for the info guys.

I shouldn't be surprised since it is not dríven by a Granny only taking it to Church on Sundays.

Mechanics have indicated that another guage of oil isn't required at this stage as the sparks plugs are clean with no indication that it is burning oil (aside from the aforementioned blue smoke).

I'll keep an eye on it this weekend when Dad is driving it around Oran Park.

Still, I am going to be obtaining some quotes to have an engine rebuilt and keep running this one this year.

Matt
NA8
Wakefield 1:14:78 28-6-09! Oran Park GP 1:27:73 30-03-08 Oran Park South 54:50 14-10-2007 Eastern Creek 2:02:44 6-8-07
BRZ
Pheasant Wood 1:05.4940

manga_blue
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Re:

Postby manga_blue » Wed Mar 26, 2008 10:42 am

Li7hium wrote:Mechanics have indicated that another guage of oil isn't required at this stage ...

I meant another compression gauge. I wouldn't trust just one set of readings.
’95 NA8


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