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chippeduk
Really Senior Member II
ECU Tech
Joined: 04-June-2004
Location: United Kingdom
Status: Offline
Points: 696
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Posted: 05-November-2004 at 14:24 |
My source is Ahmed Khan (programmer for BMW)
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daddy cool
Really Senior Member II
Joined: 27-October-2003
Location: Sussex
Status: Offline
Points: 691
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Posted: 05-November-2004 at 11:25 |
typical germans ,,, take a standard car spend thousands on research and development put a bigger engine in it to get more power then de tune it to make it slower ......... actually not like the germans at all ???
i didnty realize the 2.7 conversions released that much bhp , i shoulda just repaired my old one
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e30 2.7 cab
e30 325i
e30 325 sport
e30 318 touring
e28 m5
e28 m535
e34 m5
e39 540
e36 318ti (green)
e36 318ti (mauve)
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b318isp
Moderator Group
Joined: 10-October-2002
Location: Ireland
Status: Offline
Points: 2057
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Posted: 05-November-2004 at 10:09 |
I don't have an argument on chips - I have one in my car and there are improvements as demonstrated on a rolling road!
What is your source re. the M20 with 191bhp? For a 2v/cylinder basic engine, that's 76.4 bhp/litre which I would seriously doubt.
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chippeduk
Really Senior Member II
ECU Tech
Joined: 04-June-2004
Location: United Kingdom
Status: Offline
Points: 696
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Posted: 05-November-2004 at 08:32 |
I can try and help here.
I have a copy of an original alpina ecu code.
The C2 alpina (B3 in germany) was a 2.7 litre M20 powered car produced with 218bhp.
They released this car to the insurance people who give an estimate on insurance rating etc etc and they gave it a high grouping.
They then modded the car to give lower power and changed the mapping too produce 210hp.
I know this is not in relation to the throttle body but it shows of why manufacturers mod cars backwards to aid the selling process.
The e30 325i M20 was actually 191hp but was sold as 170hp after being throttled.
The e36 325i M50 was actually 204hp but was sold as 192hp after being throttled.
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b318isp
Moderator Group
Joined: 10-October-2002
Location: Ireland
Status: Offline
Points: 2057
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Posted: 05-November-2004 at 08:25 |
chippeduk wrote:
You can dissagree, thats an opinion and perfect for forums but the fact is, you fit the ported throttle body and you will notice the difference right away, not only top end but throughout the rev range. |
Yep, but the problem is that I have never seen fact - only peoples opinion. I'm an engineer, so I need to be otherwise convinced of opinions (by explantion) to change my point of view. There is no logic in what you say given that a throttle plate, an airflow meter flap and a valve (or two!) with its inlet tract are also in the way.
I always wonder why BMW picked specific sizes for a throttle body. Narrower pipework keeps the air flowing faster and there are other possible resonant aspects too. It could be possible that increasing the throttle bocy aperture would reduce power!
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chippeduk
Really Senior Member II
ECU Tech
Joined: 04-June-2004
Location: United Kingdom
Status: Offline
Points: 696
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Posted: 04-November-2004 at 10:59 |
I am using a hartge dif and en e36 328i box.
As for your engine, i would do the following which is proven to transform the engine and the way the car drives.
Chip
Throtle body
Sealed air filter or better pannel filter.
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daddy cool
Really Senior Member II
Joined: 27-October-2003
Location: Sussex
Status: Offline
Points: 691
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Posted: 04-November-2004 at 10:51 |
nice !!
evo motor i presume ?
tbh if performance was really the biggest issue with the car we wouldnt have bought it , but we do feel its a little sluggish hence the post .
i think its probably gna end up with a cam and a chip as long as it keeps its driveability we,l be happy . if it was a real performance issue i,d be looking at doing a low comp turbo conversion or the twin supercharged jag v8 but it really isnt worth it . i think i have spoilt myself by driving really fast cars like my saff and now it allways feels like everything else is positivly slow .
as for high power e30's , one question ,,,, what diff , g box would you use ? surely the e30 stuff wouldnt handle it too well ?
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e30 2.7 cab
e30 325i
e30 325 sport
e30 318 touring
e28 m5
e28 m535
e34 m5
e39 540
e36 318ti (green)
e36 318ti (mauve)
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chippeduk
Really Senior Member II
ECU Tech
Joined: 04-June-2004
Location: United Kingdom
Status: Offline
Points: 696
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Posted: 04-November-2004 at 09:14 |
Or you could remove the m20 and fit this instead:
Trust me, its cheaper than modding the m20
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paul325i
Really Senior Member II
Joined: 23-January-2003
Location: United Kingdom
Status: Offline
Points: 666
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Posted: 04-November-2004 at 09:06 |
chippeduk wrote:
Mind you, i`m probably a joker who is making a wild guess at all these claims :D
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Well we didn't want to say anything
Only kidding, but you're right about that level of modding, just not worth it on the M20 IMO, if i was at a stage where i needed polishing and head porting then it'd have to be on a multivalve engine to make it worth my while.
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chippeduk
Really Senior Member II
ECU Tech
Joined: 04-June-2004
Location: United Kingdom
Status: Offline
Points: 696
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Posted: 04-November-2004 at 09:01 |
P.S) my head was kinda highly modded with regards valves, ports, gear etc etc.
Mind you, i`m probably a joker who is making a wild guess at all these claims :D
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chippeduk
Really Senior Member II
ECU Tech
Joined: 04-June-2004
Location: United Kingdom
Status: Offline
Points: 696
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Posted: 04-November-2004 at 09:00 |
hehehehe.
I know all about race engines and builds.
The FACT is there are not worth the high costs when modding the M20 head.
If dave walker could only get 2hp from this head by porting and flowing then you tell me someone who can get much more.
Of course this does not relate to all engines, My escort cossie saw 14hp from head work (not cams) so i know how they work but this thread was about the m20 head.
Anyway, back to the throttle body.
You will definately see a gain throughout with the ported throttle body.
Having said that, the gains felt when driving are more spectacular.
I am yet to find someone who has done this and said they didnt notice the difference, if you know of anyone please point them here to explain.
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paul325i
Really Senior Member II
Joined: 23-January-2003
Location: United Kingdom
Status: Offline
Points: 666
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Posted: 04-November-2004 at 08:59 |
GT6-M3 wrote:
However, if you paid £3k, then you were stiched up like a kipper!
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GT6-M3
Senior Member II
Joined: 11-August-2004
Location: England
Status: Offline
Points: 237
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Posted: 04-November-2004 at 08:51 |
chippeduk wrote:
Hmmm, now for the proper answer.
The ported throttle body will give you far greater pulling power throughout the rev range and it is noticable.
Porting the head is worth 2-4hp (if you manage to make power)
I had a 3 grand head The m20 and m30 heads are very good standard.
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With respect, that thing about the TB is a load of cobblers. The engine wants to fill it's cylinders all the time that it's running. The throttle attenuates the flow so that they only partially fill and the engine doesn't rev it's big-ends off all the time.
Now, make the TB slightly better at flowing gas and all you'll get it slightly better power for a given throttle opening, but the power at a given engine speed it likely to be exactly the same as it ever was.
Only when the TB becomes a restriction in it's own right, at wide open throttle, will you notice a gain.
Also, the TB is bolted to a sand cast aluminium inlet manifold which is rough as a bears behind and doesn't exactly aid gas flow.
I'll admit that different heads respond in different ways to porting. However, if you paid £3k, then you were stiched up like a kipper! For around £700 you can get a reputable company to port a 16v head to race spec (none of this stage 1,2 and 3 <rap) so a 12v shouldn't be any more expensive.
Again though, the specific power output of these engines isn't anything to write home about and that's because they were mass produced with no particular attention being paid to the finish of the relevant bits.
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If anyone like old cars with big BMW engines, take a look at www.gt6.org.uk
sign the guestbook, you know it makes sense!
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chippeduk
Really Senior Member II
ECU Tech
Joined: 04-June-2004
Location: United Kingdom
Status: Offline
Points: 696
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Posted: 04-November-2004 at 08:37 |
You can dissagree, thats an opinion and perfect for forums but the fact is, you fit the ported throttle body and you will notice the difference right away, not only top end but throughout the rev range.
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b318isp
Moderator Group
Joined: 10-October-2002
Location: Ireland
Status: Offline
Points: 2057
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Posted: 04-November-2004 at 08:23 |
chippeduk wrote:
Hmmm, now for the proper answer.
The ported throttle body will give you far greater pulling power throughout the rev range and it is noticable.
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I disagree in the absence of other breathing mods. I have never seen evidance of this and it makes no sense anyway other that WOT given a throttle butterfly being in the way...
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chippeduk
Really Senior Member II
ECU Tech
Joined: 04-June-2004
Location: United Kingdom
Status: Offline
Points: 696
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Posted: 04-November-2004 at 07:19 |
If your going to the trouble of doing a maf conversion then i would advise changing the engine as your into a grand with setting the thing up and there are not too many people who can do it right.
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paul325i
Really Senior Member II
Joined: 23-January-2003
Location: United Kingdom
Status: Offline
Points: 666
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Posted: 04-November-2004 at 07:12 |
The E30 one won't dude, it needs the AFM and it can't interpret a MAF, but it think you buy the box which interfaces between the two.
Edited by paul325i
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daddy cool
Really Senior Member II
Joined: 27-October-2003
Location: Sussex
Status: Offline
Points: 691
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Posted: 04-November-2004 at 07:05 |
allerady has a single box , 3" stainless scorpion .
i did wonder how the ecu would run it with out the afm
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e30 2.7 cab
e30 325i
e30 325 sport
e30 318 touring
e28 m5
e28 m535
e34 m5
e39 540
e36 318ti (green)
e36 318ti (mauve)
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paul325i
Really Senior Member II
Joined: 23-January-2003
Location: United Kingdom
Status: Offline
Points: 666
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Posted: 04-November-2004 at 07:01 |
I'd use a Schrick cam, the increased size throttle body, have a MAF fitted instead of the AFM then you'll have to use stand alone management to run the fuelling, that last option won't be cheap but i've seen it in a car and felt it, sounds wicked to!
Best to have it mapped on a rolling road by a reputable firm if you're after then best gains, if you want to move the power band up the rev range then fit an aftermarket exhaust.
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daddy cool
Really Senior Member II
Joined: 27-October-2003
Location: Sussex
Status: Offline
Points: 691
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Posted: 04-November-2004 at 06:34 |
thanx fella's
as i said im not going to start porting and polishing , altering compresion or changing any major mechanical items . tbh big power gains arent possible without spending loads on any motor . but a couple more ponies or lb ft are allways nice .
what about a cam ? i fitted a schrick item in the 5 and it did the job but that was a 3.5 !
injectors ? higher cc capable injectors with a re mapped ucu to match ????
obviously a decent zaust fanimould and free flow system will help it breath but untill you get to high modification levels i cant see the benefit .
what throttle body do you suggest jason ? is it worth removing the air flow meter ? if so is it actually possible to make the ecu run it properly without one ?
what sort of power hikes are we looking at with
higher flow rate injectors, throttle body , cam ,and the filter and zaust i allready have ? someone must have done something similar allready !
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e30 2.7 cab
e30 325i
e30 325 sport
e30 318 touring
e28 m5
e28 m535
e34 m5
e39 540
e36 318ti (green)
e36 318ti (mauve)
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