Author Topic: Compression figures  (Read 4610 times)

Offline Sgt_Lemon

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Compression figures
« on: 27 August 2013, 21:15 »
What should the factory compression figures be for a 1.8 8v?
If someone can post off the Haynes PDF it might be worth putting the figures down for all other models as I couldn't find it within the section or searching in the MK2 section.

Offline gazareth

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Re: Compression figures
« Reply #1 on: 27 August 2013, 23:49 »
about 180/190 is good on standard engine. but your engine is cammed yeah. so I would just make sure they are even from cylinder to cylinder.

Offline Sgt_Lemon

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Re: Compression figures
« Reply #2 on: 28 August 2013, 11:32 »
Thanks, will check it out tomorrow.

Offline Sgt_Lemon

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Re: Compression figures
« Reply #3 on: 03 September 2013, 20:18 »
I just did a compression test, got from 1-4 figures of   150/ 145/ 145/ 145.

Offline Gambit

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Re: Compression figures
« Reply #4 on: 03 September 2013, 21:24 »
Was that with throttle wide open? Thats low, try a diff compression gauge also

Offline Sgt_Lemon

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Re: Compression figures
« Reply #5 on: 03 September 2013, 22:21 »
Throttle wide open. The book says between 145-190 is good. To be honest though I'm happy that they ae all close, not sure the tester I got at a car boot for £5 can be trusted.

Offline gazareth

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Re: Compression figures
« Reply #6 on: 03 September 2013, 22:26 »
they will read lower at cranking due to the sports cam and modified head you have fitted. but they are very even. when I tested mine one of them was 195 and other 3 were 190. did retorquing the head stop your coolant loss btw?

Offline Gambit

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Re: Compression figures
« Reply #7 on: 03 September 2013, 22:47 »
How will they read lower with cam & head job? The valves are closed so no difference in compression

145 is too low, try a different gauge

Offline clipperjay

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Re: Compression figures
« Reply #8 on: 04 September 2013, 11:54 »
Agreed okay but would personally like to see a bit higher than 145 soon or later rings or valve stems will need doing sooner than later?

Offline Sgt_Lemon

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Re: Compression figures
« Reply #9 on: 04 September 2013, 12:44 »
The tester I used wouldn't hold a value so 2 people were needed so I doubt the accuracy of the figures.