323i head on Eta????

[Super Eta]

somewhere i heard that you can put a 323i head on an Eta and it will give you a few gains from it now if this is true is it a straight bolt on or do you have to do a bit of modifying to get it to work proper.

Fill me in on the 411 with this.

[rwh11385]

i heard the same thing, it was some guy from europe......

oh yeah...... I definately believe it was Gunni!

He was saying the 323 is a perfect fit on the eta block. (I think)

there was a 323 head on Bmwe30.net I believe...... I almost posted it on here, but got distracted.

EDIT: well, shit, I can't find the head....there's someone parting one supposedly on BEN, but no head....search for 323.

[Digitalwave]

Where is that guy that said he dyno'd like 170whp with a pretty much stock 323i engine?

[Super Eta]

well if this is all true about it giving you a bit more horse then i *might* consider doing the swap.

I am not familiar with 323's so can someone give me some background info on what sets them apart from the 325i's and 325e's?

What kind of M20 do they fall into for example Eta's are M20B27 and 325i's are M20B25?

[rwh11385]

well if this is all true about it giving you a bit more horse then i *might* consider doing the swap.

I am not familiar with 323's so can someone give me some background info on what sets them apart from the 325i's and 325e's?

What kind of M20 do they fall into for example Eta's are M20B27 and 325i's are M20B25?

Number Models
M20B20 320i
M20B23 323i
M20B25 325i, 325is and 325i
M20B27 325, 325e and 325es

I'm looking for more info the the head swap......

[rwh11385]

http://babelfish.altavista.com/babelfish/urltrurl?lp=de_en&url=http%3A%2F%2Fwww.e30.de%2Fmotor%2Fm20%2Fm20.htm

2.7i conversion pages on www.e30.de

http://babelfish.altavista.com/babelfish/urltrurl?lp=de_en&url=http%3A%2F%2Fwww.e30.de%2Fmotor%2Fm20%2Fm20seite32.htm

"Page 3,1 - Variant I (122 HP 325e block, 320i head)"

Around the 325e too
entdrosseln, a 320i/323i cylinder head with all attachments must be blocked. This
Cylinder head possesses the same combustion chamber form and valve size as the 325e which in this
Range already times no problems prepares. Best one uses the most current design of the
320i with Eingebermotronic and regulated catalyst, here is then also a cam shaft
with still somewhat more opening angle than available in the 323i.

Oh yeah, whoever mentioned this orginally (Gunni I'm still beating) said the 323 cams are hotter than 325.

[Super Eta]

Robert, You have an addiction please seek help immeadiatly! :P

[rwh11385]

Robert, You have an addiction please seek help immeadiatly! :P

damn straight. I eat, drink, sleep, think BMWs 4 Life.

I just don't drive one right now......

I'm an E30 Addict.....too bad there's no 12 Step program....only 3 Pedals beeeotch!

[bimmerlover]

I'm not sure if this is exactly what ya'll are talking about or not.. but here's an article I found that's very good.

http://www.e21bmw.net/graymarket/library/327i.php

This may be stupid of me.. but I'm unsure as to whether there is a difference between the E21 323i and the E30 323i engine and if so, which one ya'll are are talking about.

I have an 82 323i (e21) and I am looking into making it a 2.7. We have lots of eta blocks floating around. I just have to find a reason to take the engine apart first. I always say, if it's not broken, don't fix it :-D


Later!

[rs4pro3]

yes there is a difference the E30 323i head has porst sizes like the I head where as the e21 head had port sizes like the eta head. Here is more info.
Small six cylinder heads
This is an article that will cover the various types of cylinder heads avalable on the small six engine.This will be of benefit to owners who want to modify their small six (E30 or E21) or simply background reading for the technically inclined.
When the small six was launched in 1977 its cylinder head came with small combustion chambers.This followed BMW's philosophy of small chambers for high thermodynamic efficiency. The small chambers allowed shorter flame paths and more resistance to detonation and pinking (or pinging to all you US folk).Now I'll vouch for that- when I first bought my 1982 323i I ran the ignition 22 degrres advanced above the reccomended setting, by mistake, for one day. All that was there was a slight metallic rustling noise at low revs/high loads. Now I would certainly not reccomend over advancing the ignition to such a magnitude as, on efficient engines this is detrimental to performance and will wreck the crank,bearings ,etc, after prolonged use but it does go to show.
In general design, the light alloy head followed normal BMW practice i.e. a cross flow head with the valves in V formation operated by a single,central camshaft pushing up on short rockers (that look like snails!).The same head casting was used for all initial models including, the 320/6,520/6 (E12) and the 323i.The combustion chambers have a volume of 37cc. This gave the 2.0 litre cars a compression ratio of 9.2:1 and the 323i one of 9.5:1.
This compactness was achieved by adopting a valve angle of 2 x 22 degrees as opposed to the earlier big six/four cylinder 2 x 26 degrees.Infact the small six's combustion chamber was more of a wedge-shape than the classic part hemisphere of past BMW's.Alot of stiffness was provided at the cam by running it with seven bearings (the big six only runs in four).This allowed the high valve lift of 10mm and squarer profiled cams (quite a common trend in engine design during late "70's/early "80's) i.e.steeper camshafts with higher valve accelerations made it possible to reduce the valve opening duration now being 260 deg compared with 264 deg and 272 deg for other BMW engines.This meant that high rev volumetric efficiency was not effected by the reduced duration with the added benfit of slightly better flexibility (claimed).Now I write a 'cynical' "claimed" because this flexibility was not reflected in road test comparing the 320/4 and 320/6. To be fair the 320/6 was marginally heavier and pulling a taller rear end ratio. The inlet ports on this early head are small and circular and of about 32mm diameter.The casting number to look for is 1264200 on the inlet side.The 323i used tuned induction pipes of 454mm length, all drawing from a common small plenum. According to BMW the plenum chamber volume is kept small to improve throttle response.
The pistons were flat topped or slightly domed in the case of the 320/6. At top dead centre the crown of the piston is below the level of the cylinder block (how much so I forget, but I can look it up) which is not good in terms of squish.A piston to head clearance of 1mm or just under is desirable otherwise the squish zones become flame front quench zones and tend to extinguish the flame front. This has been adressed in later versions of this engine such as the 325i,325e,E30 323i and E30 320i/6.This is a shame because the combustion chamber shape has a nice squish zone opposite the spark plug. When compared to other engines such as the Alfa Romeo 75/Milano V-6 the BMW chamber is a much more thermodynamically optimised affair.
The E30 320i/6 and 323i had a redesign for their cylinder heads.Again the 320i/6 and the 323i used the same head casting (1264731) with exactly the same combustion chamber shape but this time the inlet ports were enlargened to a 36.5 mm diameter.The compression ratios on both models was now 9.8:1.I have reason to believe that the cam timing duration was lowered but figures I do have conflict (I intend to get hold of a cam and measure it myself soon). I know the relatively large 110 deg Lobe Centerline Angle was retained.None of the above BMWs were officially sold in the USA.However the small six based 'Eta' engined was.This (as fitted to the 325e plus 528e-US and 525e-Europe) used the earler small port head casting (1264200) and a compression ratio of 8.0:1 in the USA (due to their lower octane fuels) and 11:1 in the UK.Three of the cam bearings were made redundant to reduce friction. The cams Lobe Centerline Angle was reduced to just 102deg with around a 236degree duration (don't quote me on that!)and low overlap.The inlet tracts of this motor are of considerable length-553mm.
However the milestone of the small- six engines was yet to come:the 325i unit (325is in the states).This head (casting number 1705885)has large U-shaped ports (about 37mm by 37mm) a slightly larger combustion chamber volume of 40cc but follows a new combustion chamber philosophy. Several studies have shown that an open chamber design (basically spherical in shape) has a faster burn rate (desirable in terms of avoiding detonation and good for efficiency) than either a classical hemi chamber (such as that used on tha Alfa V-6) or a Heron chamber(bowl in piston such as that used in VW Golfs/Rabbits).On the 1705885 head there is a dish in the piston within a dome! This is hard to explain unless it has been seen.Basically BMW engineers probably reasoned out that it would not be possible to move the spark plugs to a more central position( desirable in terms on thermodynamic efficiency) and keep the cylinder configuration the same so they moved the bulk of the chamber volume around the spark plug (which consisted of the offset dish in the piston and the hemi in the head) all the rest became squish zones.This is an outstandingly efficient package. The stroke was made shorter than the old 323i while the con rods were lengthened to increase rod to stroke ratio to reduce friction/increase top end poke.The compression ratio was 9.7:1 and 8.8:1 for the US market/later European spec. The lobe centerline angle of the camshaft was reduced again to 108 degrees but so was the duration. The late Eta used the large port "885 head (often called the 'supereta'). I have no knowledge on what kind of piston or cam timing that has been used.
R K PAUL ("82 Kaschmir gold E21 323i)

[Super Eta]

:shock:

I assume you copied and pasted and i wont be able to sit long enough to read all that i move around alot and cant stay focused on one damn thing but ill try reading it all.

[rs4pro3]

I would of posted a link to it but I don't have it on-line anywhere it was emailed to me and I'm not sure where they found it. But it is well worth the read.

[Super Eta]

yep i read and now regret not paying more attention in my Automotive class but i did understand alot of what that guy was saying though since i did of course study in that class and did some book work about Cars and their engines.

Sounds like BMW has it down to an art. lol

So basically putting an E30 323i head onto an Eta block will give it some gains i assume.

[rs4pro3]

Check out the link bimmerlover
posted as it covers the 323i head install onto a eta block.

[cheades]

I had a 323i head that I put on my 325e and it was great, really allowed the car to rev like my 325i does now. The car was definitely quicker and felt much smoother throughout the rev range than it did with the old head.