E30 Zone

Now, I know there is a difference between the 320 and 325 cam, the latter having more lift but in real terms am I better just leaving the 320 cam in the head rather than trying to source a 323 one.

Does anyone actually have all the specs on these. I've heard from this page:

http://www.e30tech.com/forum/showthread.php?t=104109

320/323 = 264 degree
325 = 256 degree

This suggests that the 320 and 323 are one and the same?!

I've got to make my mind up today really what I go for...

Another website quoting the same.

This would suggest that the 323 and 320 cams are infact the same:

M20B25 : 264 degrees with cat and 260 without, 108 degree lobe separation, 10 mm lift
M20B20/B23 : 252 degrees without cat.

And I've actually just discovered that the cams in the 323 where the same in the 320 when it was still being. If you search on the part number.

Does that suggest that they (BMW) altered the cam in later models to make it less aggressive in the 320?

Has anyone got a 2.7 with the stock 320 cam in?

I have a 2.7 with a 2.5 head and cam... And its great! Iv never been in a 2.7 with a 2.0 cam but iv heard the torque delievery is good.. Is it any better than a 2.5 cam in torque?? Im not sure...

Might leave the 320 cam in then, its not worn much. Save me a few quid as well!

Do I need to do anything to the head to get the 325 cam in there? I'm trying to find a post on here that suggested it needed machining?

Is it a 2.0? If so, leave the cam in there.....

Give daimlerman (malcolm) a PM.. He knows his stuff abouts cams and what can be used for a 2.7 build

This thread?

http://www.e30zone.net/modules.php?name ... c&start=25

I seem to remember seeing a comparison between the 4 BMW supplied M20 cams(320,323,325 and eta)that indicated that the 323 item was the most aggressive of the four.

Now back in the early '80's/late '70's,an E21 323i was considered to be quite an animal,about 140ish BHP compaired to the carb fed 320 at about 115bhp,now the addition of fuel injection and 300cc would not account for the power hike without a different cam,surely?

I have tried a (GSF supplied)325 cam and currently have a 323 cam in my 2.7,and the power delivery is very different,325 cam gave a 'flat' torque curve with almost max power from 2000rpm,but was all done by about 5200rpm,the 323 item gives a torque 'peak' at around 4000rpm,but is still pulling like a train at 6000+rpm.

Now I have not tried a 320 cam,my gut feeling is that GSF sold me an 'M20 cam'....ie,as far as they are concerned,one size fits all,but that could just be me being a little cynical!

This is a good read:

http://en.wikipedia.org/wiki/BMW_M20

I'd like to try and get hold of a cam from the 323 but I suppose this won't be an option nowdays.

A new 325 cam is 100 smackers....

You don't happen to have a spare good cam pulley do you mal, mines cracked!

monkeyboy1979 wrote:This is a good read:

http://en.wikipedia.org/wiki/BMW_M20

I'd like to try and get hold of a cam from the 323 but I suppose this won't be an option nowdays.

A new 325 cam is 100 smackers....

You don't happen to have a spare good cam pulley do you mal, mines cracked!

Took me a while to find a good,s/h cam.

GSF cam was about £80,IIRC

Yes,£10 plus £2 p/p?
Do you want both bits,or just the cog wheel?