| Coyote |
Posted
Sunday, Mar 4th 11:59pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 23
Argentina
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simply that. |
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| Marquis_Rex |
Posted
Monday, Mar 5th 11:20am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 522
UK
BMW 323i 2.7-as featured in Total BMW Nov 2002,Porsche 911/993TT |
This is the kind of question that is best answered after extensive study, calculation and measurement. A company like FEV (germany consultancy), Cosworth or AVL would charge litterally thousands to answer this.
You could ask someone who's already done it, but even if they've dynod their car- I wouldn't trust the figures from any old inertia or water brake dyno-especially when you see some of the figures quoted.
Sorry, no real clear answer.
I myself would build a model of said engine using benchmark BMW data- for stuff I didn't have- such as intake and exhaust losses, combustion etc etc, and then populate it with Turbo-compressor isentropic efficiecy maps. Then I would optimise the cam profiles. This would get me within 5%- however I have no interest in Turbo engines.
So you see, it's not an easy question to answer.
Alternative you could listen to the advice of some "internet Guru"- Besserwisser!  |
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| Coyote |
Posted
Tuesday, Mar 6th 4:41am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 24
Argentina
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i meant from the popular aftermarket cams, such as schrick, etc |
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| JJG323 |
Posted
Tuesday, Mar 6th 6:17am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1314
Reading MA USA
1979 BMW 323i |
| Coyote wrote: | | i meant from the popular aftermarket cams, such as schrick, etc |
For the 323i e21 2.3 liter m20 and k-jet you can run up to a shrick 288 cam. |
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| Marquis_Rex |
Posted
Tuesday, Mar 6th 3:24pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 523
UK
BMW 323i 2.7-as featured in Total BMW Nov 2002,Porsche 911/993TT |
| Coyote wrote: | | i meant from the popular aftermarket cams, such as schrick, etc |
Doesn't change the fact that for a turbo charged engines you need different cam profiles.
The Schrick profiles were designed to be run on naturally aspirated vehicles. Boosted engines ideally have less overlap (to avoid blow through/short circuiting of charge) and less duration than their naturally aspirated cousins.
You could Just fricken do it and choose whatever and hope for the best |
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| imaradiostar |
Posted
Tuesday, Mar 6th 6:56pm [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 1026
Nashville, TN
81 323i, 82 525i, 85 524td, 90 535i |
I think you have two pretty decent options, one is easy and one isn't. Metric Mechanic makes a few different M20 camshafts that are pretty aggressive in duration and lift but have steep ramps and low overlap. You would be in for about $750 bucks between the cam and the matching springs. Getting the MM springs is a very very good idea- Jim can explain it to you.
The other option is a PPF turbo cam. They're the supplier for the parts of a lot of the Swedish turbo m20's that are making a ton of power.
The stock cam isn't a bad choice- it won't rev sky high but it has reasonable overlap and duration for a turbo car.
jamie
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| Turbo3er |
Posted
Monday, Mar 12th 11:18pm [Edit] [Quote] [IMS] [View car] |
Junior Member
Post nr. 2
87 325e 87 325es 94 325Is |
i'm running a bmp design cam that is 288int 272exh 11.5mm int/11.0mm exh lift, in my e30 325 m20b27 and getting ready to turbo charge it in the next month or 2. it runs like a scalded dog n/a right now, and i think it might be just the profile i'm looking for when its turbo. |
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| Bill in MN |
Posted
Tuesday, Mar 13th 2:35am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 130
Minnesota USA
1988 735, 1986 535 turbo, 1981 Baur 323i |
When my 535 was NA I ran a pretty hot cam and once turbo'ed it ran like crap. I then put in a pretty sedate 272 and life was much different. Most "turbo" cams are pretty tame in reality.
Talk to Todd at TCD. He's done some pretty serious M20 turbos recently and is always willing to give advice. |
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| Coyote |
Posted
Thursday, Mar 15th 6:24am [Edit] [Quote] [IMS] [View car] |
Member
Post nr. 26
Argentina
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great ppl, lots of useful information. thanks. |
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