325i piston compression?

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urfy
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Post Wed Aug 21, 2013 2:47 pm

Can anyone tell me what the factory piston compression be for a 325i?
Also what should I expect from a rebuilt engine (new rings, bearings)?
89 BMW E30 325i Sport
93 BMW E30 325i Cabriolet
89 Mercedes 190E 2.5-16 Cosworth
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maggspower
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Post Wed Aug 21, 2013 2:55 pm

Depends what engine it is:

25 6 E1 is 9.7:1
25 6 E2 is 9.4:1
25 6 K1 is 8.8:1

The number will be on a machined flat near the bottom of the dipstick tube.
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urfy
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Post Wed Aug 21, 2013 3:02 pm

maggspower wrote:Depends what engine it is:

25 6 E1 is 9.7:1
25 6 E2 is 9.4:1
25 6 K1 is 8.8:1

The number will be on a machined flat near the bottom of the dipstick tube.
25 6 k1
89 BMW E30 325i Sport
93 BMW E30 325i Cabriolet
89 Mercedes 190E 2.5-16 Cosworth
86 Mercedes 190E 2.3-16 Cosworth
96 Mercedes E320 CE Sportline
88 Nissan Bluebird ZX Turbo
89 Nissan Bluebird Executive Turbo
Speedtouch
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Post Wed Aug 21, 2013 3:39 pm

Standard factory power output figure was 171bhp, though some early high compression ones were more like 180bhp, while some later low compression ones struggled to achieve 160bhp.

A chip can improve things somewhat. winkeye
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
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urfy
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Post Wed Aug 21, 2013 3:57 pm

Speedtouch wrote:Standard factory power output figure was 171bhp, though some early high compression ones were more like 180bhp, while some later low compression ones struggled to achieve 160bhp.

A chip can improve things somewhat. winkeye
Sorry if I wasnt clear but I was talking about the figures for compression for each cylinder (as if your doing a compression test)
89 BMW E30 325i Sport
93 BMW E30 325i Cabriolet
89 Mercedes 190E 2.5-16 Cosworth
86 Mercedes 190E 2.3-16 Cosworth
96 Mercedes E320 CE Sportline
88 Nissan Bluebird ZX Turbo
89 Nissan Bluebird Executive Turbo
Speedtouch
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Post Wed Aug 21, 2013 3:59 pm

They are usually around the 150-160psi (10-11 bar) mark.
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
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urfy
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Post Wed Aug 21, 2013 4:11 pm

Speedtouch wrote:They are usually around the 150-160psi (10-11 bar) mark.
oh I was expecting to be 180+ psi
89 BMW E30 325i Sport
93 BMW E30 325i Cabriolet
89 Mercedes 190E 2.5-16 Cosworth
86 Mercedes 190E 2.3-16 Cosworth
96 Mercedes E320 CE Sportline
88 Nissan Bluebird ZX Turbo
89 Nissan Bluebird Executive Turbo
Speedtouch
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Location: Canterbury

Post Wed Aug 21, 2013 4:15 pm

Some are indeed that high.
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421