M104 Cylinder Head differences... - Page 11 - PeachParts Mercedes-Benz Forum

MAG58 · #**151** 02-28-2010, 11:35 AM

Quote:

Originally Posted by JayRash

ok so that means the M104 head is goood? And what supra engine was that?

No, that doesn't mean it's good. It's quite bad actually.

And I've seen that website before, I didn't post it because I see a few numbers that don't seem right. IIRC the information it was located from wasn't in CFM's or 28'' so there was conversion going on.

kynsi · #**152** 02-28-2010, 02:15 PM

That website was just what google found for 2jzgte.

Im interested to see figures from other flow bench for M103 and 104 heads. If possible could you write them here in this topic?

My flow bench figures is tested in 10" of water, and that 28" field is actually calculated by program, so... lets not belive its absolute right.

Oh.. and i didnt say supra head is good, but in some videos it sounds just nice whith big turbo.

MAG58 · #**153** 02-28-2010, 03:27 PM

Quote:

Originally Posted by kynsi

Oh.. and i didnt say supra head is good, but in some videos it sounds just nice whith big turbo.

It's also quite a bit heavier than the M104... It does sound sweet though. But the shorter stroke M104's should be able to rev higher...

400Eric · #**154** 03-01-2010, 12:04 AM

Did anybody look at that head flow site I linked?

MAG58 · #**155** 03-01-2010, 12:43 AM

Quote:

Originally Posted by 400Eric

Did anybody look at that head flow site I linked?

Quote:

Originally Posted by MAG58

And I've seen that website before, I didn't post it because I see a few numbers that don't seem right. IIRC the information it was located from wasn't in CFM's or 28'' so there was conversion going on.

The website has lots of good info, but just browsing through other motors that I have seen flow benched before at 28'' and know what the flow is, I see some misinformation.

400Eric · #**156** 03-01-2010, 03:24 AM

I think the site posts ALL of the available info out there, even the ones that don't check out, in the interest of fair play. You've got to admit there isn't another site out there that has so many flow figures of so many different heads all in one place. Even Studebaker heads! You've also got to admit that a lot of the numbers there are very accurate.
Regards, Eric

kynsi · #**157** 03-01-2010, 08:00 AM

Quote:

Originally Posted by MAG58

It's also quite a bit heavier than the M104... It does sound sweet though. But the shorter stroke M104's should be able to rev higher...

Comparing Toyota and Merc Iv been thinking about same thing. Keeping the stroke 80.25 and still having 3 litre 24v turbo . M 104 also have little bit bigger valves...

MAG58 · #**158** 03-01-2010, 10:47 AM

Quote:

Originally Posted by kynsi

Comparing Toyota and Merc Iv been thinking about same thing. Keeping the stroke 80.25 and still having 3 litre 24v turbo . M 104 also have little bit bigger valves...

It also has a larger bore spacing, IIRC a larger coolant area in the block, a chain driven set of cams, bigger head bolts, and a better rod/stroke ratio...

AustinsCE · #**159** 03-02-2010, 04:30 PM

What about the RBXX series, they seemed to flow well on that chart, at least the intake. One of the biggest draws to the 104 for me is the fact that it doesn't start mixing fluids. My HG is throwing buckets of oil, but there's not much mixing. The flow doesn't seem to affect it's ability to make HP. 217 from an N/A 3.0 is pretty impressive, especially with mechanical fuel injection. I can only imagine what it could have done with new valve technology, direct injection, and both cams being variable. MB screwed the pooch, and now they're downsizing engines and using turbos!!!!

kynsi · #**160** 03-03-2010, 10:39 AM

We are driving one untouched m103 head in same flowbench soon...

400Eric · #**161** 03-04-2010, 04:14 AM

Cool!!!!
Regards, Eric

pentoman · #**162** 03-06-2010, 12:47 PM

Hi,

This thread makes very interesting reading. I like to learn more about Mercedes engine design. Just wanted to add some comments (sorry they're a bit out of date.

Quote:

Originally Posted by JayRash

Eric, i know but even the 3.0 and 3.2 of the same yrs made alot more power (286Hp & 321HP).

We got this BMW in the UK - S52 motor (3.0 286hp from approx 93-97, and 3.2 321hp from 97-99). What I can say is that in the UK it's a well known fact the 3.2 version does not manage the quoted output. They make 305-310hp in reality. Also the motor had double VANOS (BMW's form of variable valve timing) but am I right in thinking that just affects torque curve, doesn't affect top-end power? Or perhaps it does affect top end power because you can get better emissions and still the car is road legal even with high power output?

Quote:

Originally Posted by 400Eric

I don't think M.B.'s switch away from CIS-E gained them much horsepower because the 5.0 M119 didn't gain even 1 horsepower when it ditched CIS-E. Remember, the M119 did not get a new head design when it switched F.I. systems.

Well officially there is no difference but of course sometimes the manufacturers lie. Or perhaps it is better with EFI, but they wanted to keep power to ~325hp (it is plenty after all) and instead change the cams for better torque and still maintained the same power? But actually I think you're right there CIS-E is not too bad for power. Remember 2.5-16 Evo II makes ~235hp from on it. And 2.5 S14 bmw engine only makes ~240hp with EFI and independent throttle bodies. That said my friend has a 1990 2.3 S14 bmw with 269hp! Make me cry a bit. My 2.5-16 made 187hp on the same dyno

. I wish there was more Mercedes engine expertise around - but what I am reading here is good learning!

JayRash · #**163** 03-07-2010, 04:45 AM

well double variable cam control gives u the ability to run sportier cams yet still make enough torque low down.
And it lets u run more cam retard at high revs extending the power rpm range.

MAG58 · #**164** 03-08-2010, 10:24 AM

Quote:

Originally Posted by JayRash

well double variable cam control gives u the ability to run sportier cams yet still make enough torque low down.
And it lets u run more cam retard at high revs extending the power rpm range.

Not quite. But that's the general idea. Once cams get past a certain size though, the overlap and static Lobe Center Angle gets to the point where as much movement as VANOS or the adjuster on the MB intake cam is actually a hinderance. So you either have to modify the gross cam movement (I'm not sure if VANOS is infinitely variable or just on/off like MB) or remove it. I'm probably going to be using pretty healthy cams and pushing the powerband way up in the powerband (I can afford it, my car is 1200lbs less than the lightest W124...) and seeing how linear I can get response and power between 4k and 8500 so I'm just going to use two exhaust cams as cores to a hardface and then removing the adjuster.

kynsi · #**165** 03-09-2010, 09:45 AM

Quote:

Originally Posted by MAG58

I'm just going to use two exhaust cams .

Same here, intake has so little duraton. I threw it away too. Exhaust cam looks more like normal sporty cam. How did you make base cirkle compensate. By removing those little sockets from hydraulic adjusters?