320i head on a 2.7 block

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visionz
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Wed Jun 14, 2006 5:28 pm

what would happen if i did this.. it's an m20.. just wondered :) would it be pap? cheers
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Brianmoooore
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Wed Jun 14, 2006 10:52 pm

First of all, welcome to the zone.
This one's been discussed many, many times on the zone. A forum search (use the button under the page header), should show up dozens of posts on the subject.
Short answer is: you will produce an engine developing a useful amount more power than a 325, with a lot more torque.
You will need to use the motronic management system, a 325 inlet manifold and throttle body, and a zone 2.7 chip in the ECU.
Only machining needed is opening out the ports of the head slightly to match the 325 manifold
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eRgal
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Wed Jun 14, 2006 11:38 pm

Hi,

I have looked at this subject for hours and still cannot make up my mind what makes the best 2.7 engine, There does seem to be a lot of conflict of opinion as to what bits make the best 2.7

Would the 320i head on the 325i block give a noticable increase ? and would the eta block improve this further.

Thx David.
Templ8e30
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Thu Jun 15, 2006 12:57 am

eRgal wrote:Hi,

I have looked at this subject for hours and still cannot make up my mind what makes the best 2.7 engine, There does seem to be a lot of conflict of opinion as to what bits make the best 2.7

Would the 320i head on the 325i block give a noticable increase ? and would the eta block improve this further.

Thx David.
You can't fit a 320i head to the 325i block as the pistons will clash with the head. The 325i pistons have a unique shape and will only work with a 325i head.

Best 2.7 is 325i head with 325i pistons machined to fit into either a 325i or 525e block using the 525e crank and non-325i conrods. The block will have to have about 1.5mm shaved off the top to get the correct piston height.

All non-325i conrods are the same part.

You'll also need a vernier adjustable cam pulley to compensate for the shaved block.

A good camshaft of at least 272 degrees is also desirable.

Get building winkeye

Cheers,

Iain T
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eRgal
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Thu Jun 15, 2006 12:10 pm

ah soz I read orginal post wrong , Thought he had said 2.5 block but its 2.7

:oops:
Geeman
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Thu Jun 15, 2006 12:13 pm

Iain speaks the truth, but a 320 head on a 525e block will be a good unit if you do the things that Brian says. This is the simplest route to 2.7 power. Wouldn't hurt to add a cam too.
visionz
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Thu Jun 15, 2006 1:50 pm

Thanks guys :)
DennesShi
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Thu Jun 15, 2006 4:41 pm

Where doing the same thing with my 2.7 eta egine, we put a shaved 2.0 head on this eta block. And i don't need the oil cooler anymore, which you need with a 2.5 or 2.7 head.

give me more power please babe winkeye
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