I heard something interesting on the weekend.
I was told you can get more low-down torque on the 280 by advancing the intake cam by 2 teeth.
This will make the power band come in at lower revs.
The downside is you use a little more fuel and increase emissions as well.
Has anyone done this to their 280?
.
do the 280's have DOHC???
Yep.... ;D
It will also increase timing overlap (look it up) resulting in a very lumpy idle (think of those wankel engine cars I work on with that brap brap brap idle - thats because those engines have up to 150 degrees of intake/exhaust overlap).
Not to sure about your low end torque though... those sorts of mods as applied to a US V8 engie or a wankel engine results in more top-end power at the expense of low end power, torque and driveability.
This chart shows a lightly modified 13B with only 10 degrees overlap and it makes about 115 RWHP and the torque is pretty flat, it starts low, peaks around mid rpm (4000) and drops off thereafter:
(http://ianmav.customer.netspace.net.au/auctions/rx7-dyno.jpg)
This chart shows a highly modified 13B "Bridge Port" race engine with 150 degrees of overlap. It makes 170RWHP but see how the torque is "flat" at the higher revs and peters right off at low revs:
(http://ianmav.customer.netspace.net.au/auctions/dynotest.jpg)
Why didn't the Kraut's not be so stingy and put DOHC's in the 117's then??!!??!! ???
Not fair... :'(
Quote from: SELfor50 on 30 December 2007, 07:48 AM
do the 280's have DOHC???
indeedy and the M110 is a fine piece of machinery.
Anyone keen to develop variable inlet cam timing?
.
Quote from: Patrick Bateman on 30 December 2007, 04:28 PM
because it would of made the v8's even more massive.. Just take a look at the difference in size of the head on an m110 and its sohc father. its like double the width.
Also, have a look at the m119 at mercedesengines.net (http://www.mercedesengines.net/products.asp?cat=37) Well i think it is but it'll give an idea of how much bigger the cam boxes are for quad cams. (or is the term dual dual overhead ??? )
Quote from: 13B on 30 December 2007, 07:58 AM
It will also increase timing overlap (look it up) resulting in a very lumpy idle (think of those wankel engine cars I work on with that brap brap brap idle - thats because those engines have up to 150 degrees of intake/exhaust overlap).
My 280S gives a spit & fart kind of idle which reminds me of a dragster at idle, then it really comes to life when it's revved. But I can't say the power is anything to write home about. Yeah it's got a number of issues still to resolve but the above has got me thinking that the cam timing has to be put up the list. I really have to get everything right first before experimenting with intake cam timing but it will be interesting to know how far mine is out and/or if a little adjustment makes a positive difference to the norm.
Quote from: 13B on 30 December 2007, 07:58 AM
Not to sure about your low end torque though... those sorts of mods as applied to a US V8 engie or a wankel engine results in more top-end power at the expense of low end power, torque and driveability.
Agree, I would have thought going the other way, retarding the cam would do more for the low end.
Years ago I read something about replacing camshafts, it said if you can't get the timing right on, lean towards retard for this reason.
koan
Well this is very interesting...for lazy cruising purposes, more low down torque for the M110 isn't a bad thing...
Although I'm not sure I will ever go to the trouble of doing so, because it's fun getting all that power from the higher rev range when it makes that truly glorious sound ;D
Quote from: Andrew280SEL on 01 January 2008, 04:39 AM
Although I'm not sure I will ever go to the trouble of doing so, because it's fun getting all that power from the higher rev range when it makes that truly glorious sound ;D
I agree, once you get up above 80 and the M110 really comes alive and starts to roar, well mine does, it has this deafening loud BUURRRRRRR to it, I've looked under it and the exaust seems brand new so maybe it has some sort of extrators or better flow through system fitted.
The M110 motor has always been my yardstick to how Mercedes Motors should sound.
Bill
Quote from: Des on 02 January 2008, 09:51 PM
I agree, once you get up above 80 and the M110 really comes alive and starts to roar, well mine does, it has this deafening loud BUURRRRRRR to it, I've looked under it and the exaust seems brand new so maybe it has some sort of extrators or better flow through system fitted.
It's probably quite possible you have something different installed, 'cos I can't say mine is deafening in volume at that speed. But the sound is fantastic that's for sure. Although once I have the engine going past 4000-5000 RPM it starts to get loud - but this is a good thing, because of the sound. ;D
I just love the sound of my M110. It sounds like a well-calibrated and well-oiled industrial sewing machine; it idles very smoothly (noticeably smoother than two friends' W124 300Es with far fewer Ks on their clocks) and winds up respectably enough. Once it reaches about 85 km/h (no tacho - yet - in Boris) it takes on another life and pulls away from any vehicle I want behind me; it eats hills, chews them up, and spits them out like they were the slightest inclines.
A friend who owns a 5-litre V8 WB Holden ute was gobsmacked when he took Boris for a drive; his old WB (running on gas and petrol) was utterly gutless by comparison, though both cars had similar Ks on the clock (300,000).
That said, a tad more low-down torque would be nice to have - but not at the expense of the current smooth idle and utterly reliable instant start-up every time.
Anyone know what the specs were for the AMGed M110 (I think it came only in the W123)?
Quote from: OzBenzHead on 03 January 2008, 05:15 AM
Anyone know what the specs were for the AMGed M110 (I think it came only in the W123)?
Young Gordon, ask and yee shall receive:
http://ozbenz.net/download.php?id=232&mode=view
Quote from: Andrew280SEL on 03 January 2008, 01:59 AM
It's probably quite possible you have something different installed, 'cos I can't say mine is deafening in volume at that speed. But the sound is fantastic that's for sure. Although once I have the engine going past 4000-5000 RPM it starts to get loud - but this is a good thing, because of the sound. ;D
It starts coming in about 70, then 80 you hear it, then it just BRRRRRRRR's
I'll have to try and record it
What does your's sound like?
My clock has stopped and it dosen't have a tacho, going to replace it with a clock/tacho combo soon
Des: Thanks for the link - but all I get is the "You are not authorised to view, download or link from/to this site" message. ??? ??? This is despite my being logged in.
Shall search around for it later - am off to other pastures for a little while (my language forums).
I'd be happy just to pose by having an AMG rocker cover on the 280S ;D But yes the real deal would be better.
Interesting that the pic below shows a d-jet one in a w114. I assumed too that the AMG M110 existed in w123's only and CIS injection. :-\
(http://img245.imageshack.us/img245/4493/amgm110ak7.jpg) (http://imageshack.us)
Quote from: OzBenzHead on 03 January 2008, 05:52 AM
Des: Thanks for the link - but all I get is the "You are not authorised to view, download or link from/to this site" message. ??? ??? This is despite my being logged in.
Shall search around for it later - am off to other pastures for a little while (my language forums).
oh ok, humm not sure why it is doing that
if you go to Ozbenz
visit the W123 forum
scroll down to the 1980's AMG brochure picture thread and view that
Des
Des, was this the link to the w123gassers forum. i was just there trying to find that rocker cover pic. Could've sworn Nutz posted some info about the AMGM110. FWIW, that second link didn't seem to work - the m110.org site.
Also, i got the same error that OBH did. But is the first link on the w123gasser's site the same as your ozbenz link?
EDIT: forgot the link http://w123gassers.smfforfree2.com/index.php/topic,150.0.html (http://w123gassers.smfforfree2.com/index.php/topic,150.0.html)
Quote from: Des on 03 January 2008, 05:25 AM
Quote from: Andrew280SEL on 03 January 2008, 01:59 AM
It's probably quite possible you have something different installed, 'cos I can't say mine is deafening in volume at that speed. But the sound is fantastic that's for sure. Although once I have the engine going past 4000-5000 RPM it starts to get loud - but this is a good thing, because of the sound. ;D
It starts coming in about 70, then 80 you hear it, then it just BRRRRRRRR's
I'll have to try and record it
What does your's sound like?
Hmm...bit hard to say after driving the 350 so much lately...but I'd say it sounds much the same as what you describe, perhaps only alot quieter? If I've got the radio going, the engine is only really audible once the revs start to really come on (i.e that twin cam roar that sounds so awesome)
My tacho doesn't work in my 280 so unfortunately I can't say what revs exactly.
Quote from: OzBenzHead on 03 January 2008, 05:15 AM
I just love the sound of my M110. It sounds like a well-calibrated and well-oiled industrial sewing machine; it idles very smoothly (noticeably smoother than two friends' W124 300Es with far fewer Ks on their clocks) and winds up respectably enough. Once it reaches about 85 km/h (no tacho - yet - in Boris) it takes on another life and pulls away from any vehicle I want behind me; it eats hills, chews them up, and spits them out like they were the slightest inclines.
A friend who owns a 5-litre V8 WB Holden ute was gobsmacked when he took Boris for a drive; his old WB (running on gas and petrol) was utterly gutless by comparison, though both cars had similar Ks on the clock (300,000).
Wow, I think my half-a-million km 280 might be a tad more worn than I thought...it goes well, but it doesn't sound like that description! Then again it does need it's injectors sorting out. :)
http://img245.imageshack.us/img245/4493/amgm110ak7.jpg
OOOOooohhhh for xmas this year...I think thats guna be on the list.
My SEL has the sounds of a worn out exhaust and has a cracked Y joint, BUT sink the welly and it gets a very nasty growl, the more I listen to it, the more I think a sports exhaust would make it. BUT I'd keep the twin outlets, make it look stock.
Quote from: oscar on 03 January 2008, 06:03 AM
Des, was this the link to the w123gassers forum.
No?
http://ozbenz.net/
Australian mercedes forum.