PeachParts Mercedes-Benz Forum - m104 turbo project (c280)

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Quote:

Originally Posted by Turbo E320 (Post 1880497)

Hate to sound indignant here but the car i was talking about is running 12psi with over 178000 miles, probably more now since it is a daily driver. Its an all stock engine and i reread the thread and it makes over 400hp at .7 bar. So think with a turbo you could figure in 10-20 more horses because of power loss due to his belt driven supercharger. I havent read any instances of blown head gaskets or anything. My motor only has 51K on it so im starting pretty well off.

Is that car running a complete stand alone ECU??? As i said, and as its obvious that i am no expert, i would love to be prooven wrong on this, well why it seems the head gasket blew because the electronic controller i have made to enrich under boost had a loose connection. I did hear knock on my last run before the gasket gave way. If that car is running 12 psi, it gives me hope knowing i can run 8 psi for ever.

It runs an SAFC, a 250 dollar fuel adj. piggyback ecu. It is a OBDII fuel injected engine so many inexpensive piggyback units work like greddy emanage, aem fuel/ignition controller, and the Apexi SAFC I, SAFC II and SAFC NEO. If you need correct fuel cant you just do it GM style and mount a injector in or around the throttle body and wire a standalone system only on that one injector.

Maybe this, im not sure of its electrical requirements though: http://store.tlsperformance.com/spsetimaco01.html

What kind of software does your car actually have? Sensors? OBD 0,I or II? MAF/MAP?

ok here we go :rolleyes:

to start with i am running a wideband o2 sensor permenantly mounted in my car, and for those of you unfamiliar with what that is, it is a sensor which measures how much fuel and air is in the exhaust mix to tell me if my car is running rich or lean. and i use this readouts and tune my car usings maps on a laptop hoocked to the greddy ecu i have hooked into my car, in my view the only thing better than this i can do is full standalone, which i dont feel is neceseccary for only around 10psi.

in my view 310cc injectors are not big enough - not even with a rising rate fpr,

at present i am running 8psi thru my 280 and with the 310cc injectors it is too lean for comfort (heading into the 14-15:1 bracket around 6k)

and if i got a 5bar fpr i feel i would only just get it back into a more comfortable zone, but still not enough

4 bar 310cc injectors at 5 bar = 350cc,
350cc is still to small.
i would like to be in the 12.5:1 under full laod and are not raising boost until i get into this range (which i would just achieve with a higher fuel pressure but give me no room for higher boost as the 310s would be maxed.

blown_m104 runs a water injection system which allows him to get away with higher a/r ratios which i completely imagine he is getting only running 310s.

but for you turboe320, from my experience (running my wideband O2 fulltime on my 280) if you arnt going to get water injection there is no way i would go past 8psi with only 310cc injectors,

and all u guys no more hp figures mentioned in my post until i get dyno numbers for proof

peace

guys thanks for all the info and yes i will have to go with the extra injector option. and yes 12.5 psi on high compression engine is possible if running water injection system, even with higher than AVG AFRs.
@C280: Man please feel free to post anything you feel like, my intention was to speak my mind, and if i came on strongly my apology, surely wasn’t meant that way.

I highly respect this forum, and so far all members have shown a high caliber compared to other forums I have seen before, keep it up guys and keep the flow of info going.

Quote:

Originally Posted by c280nz (Post 1880546)

Not running HFM like most of you, but K-Jetronic semi electronic injection.
Stock injectors, fuel regulator and fuel pump.

Two additional injectors mounted in place of the rubber boot that is in between the air valve assembly and the throttle body.
Additional injectors controlled by an inexpensive Split Second additional injector controller.

Computer mapped thru software and fixed at .85 Lambda under boost.

Twin Garrett T2's set at .48 bar, chassis rail mounted intercooler, forced air into the intake filter assembly.

Twin 2" downpipes each to individual Magnaflow spun metal cats.
Wide band O2 sensor installed before the cats.
Each cat exits with 2" exhaust pipe to the rear silencer.

60% - 70% power increase over baseline, but a meager 210 HP under boost on a Mustang load dyno.

Why try to reinvent the wheel?
It has been proven by hundreds of installs using kits designed by premier turbo tuners that the small twin compressors work better on the M103 and M104 variants.

Boost develops around 1500 rpm, zero lag, instant torque.

Large compressor requires more gas to spool up which gives the lag.
Too much boost may give what appears to be incredible power, but also less then impressive performance....

Bigger injectors, higher fuel pressure will not reliably enrich an engine that is controlled by a piggy back unit on the stock ECU.

Let's see dyno charts and the resulting 1/4 mile results which prove the install.

Blown M104 posted dyno results, but if you read his thread he built a conservative motor not using high pressure.

All the mega horsepower Swedish built engines indicate boost beginning around 3000 rpm and have yet to post any dyno charts, just numerical printouts.

Important the the shape of the curve...

I'll put my 210HP conservative engine which develops max torque around 4000 rpm against a 500 HP M103 that develops torque and HP closer to 6000 rpm and I'll be gone by the time they are making power.

These are not high rev Japanese motors, they are high torque low rev German motors....

On my stock M103-12V the published torque is higher then the published HP...which should tell you how to build the motor and what you'll get from it !!!

Post your results and good luck...you might discover something that has been missed for the last twenty years !!!

Quote:

Originally Posted by Turbo E320 (Post 1880535)

Maybe this, im not sure of its electrical requirements though: http://store.tlsperformance.com/spsetimaco01.html

What kind of software does your car actually have? Sensors? OBD 0,I or II? MAF/MAP?

What you posted is the Split Second unit that I have used on my install for over a year.

http://i19.photobucket.com/albums/b183/rbycc/TTCM10.jpg

I would highly recommend it....

You can make the M103 and M104 variants into a rather simple and reliable turbo install by using additional injectors and a stand alone control.

This method allows the basic engine to remain stock, no messing with the original injection or control and not upsetting emissions.

This method assures passing state emissions tests.

In essence you have a stock engine control that doesn't know it has a turbo...

Same injectors, fuel regulator, fuel pump etc...

Very simple and to the point.

Without exact and reliable fuel mapping you'll lose an engine thru a lean condition !!!

Theres so much information now, we should work on a mercedes turbo/supercharged bible for the m103 and m104 engines. It would be a great sticky for the top.

Anyhow heres my progress, im in the last stage of fab with this for the oil drain. I am running water injection like Blown_m104 and anything over 4-6 psi will turn it on and I am using the 5 bar fpr.
http://img219.imageshack.us/img219/5...ldrain1wy5.jpg
http://img219.imageshack.us/img219/5...db7f6bba9f.jpg

my car with a single turbo is working fine so far, the turbo starts spooling around the 3 grand mark and heading up past 5psi round 3500, this suits my cars characteristics (with a lw-flywheel giving a fast rev) and my driving style perfectly, and thus i would recommend to anyone to go with a large single imo,
this also provides good flow to prevent running out of boost up top,

with the t3 t4 hybrid design, it has a small exhaust housing size for quick spooling, and a larger compressor housing for more efficient larger flow,
i talked to a few turbo guys before deciding on the exact turbo specs to get.
alot simplier plumbing with a large single aswell,

as rbycc has pointed out the most important thing is to not run it lean or u risk melting important parts :-)
i highly reccomend anyone doing a turbo project and there own tuning invest in a wideband o2 sensor.

here are a some fuel/air tuning rules of thumb
6.0:1 Rich run limit
9.0:1 Low power, black smoke
11.5:1 Rich best torque at WOT
12.5:1 Safe best power at WOT
13.2:1 Lean best torque at WOT
14.7:1 Chemically ideal
15.5:1 Lean light load, part throttle
16.2:1 Best economy, part throttle
18-22:1 Lean run limit

i have also retarded my timing by 6 degrees using the ignition retard module, to help prevent detonation,

another thing im going to be shopping for next is a heavier clutch, i may have to go to a puck clutch, and heavier pressure plate to help get the power down

Quote:

Originally Posted by c280nz (Post 1882577)

I along with professional tuners and manufacturers tend to disagree with you...

On a small displacement low revving motor twin turbos produce more useable power and are more efficient then a single large compressor....
No one has used a single turbo in the last twenty years with any success.

Only to look at the new BMW 335 engine.

You start to spool up at 3000 rpm and get 5 psi boost at 3500...

I spool up at 1500 rpm and get full boost ( .5 bar ) at 3000 rpm.

You retard timing to prevent detonation which sacrifices power whereas I advance timing with no detonation and increase power.

A Merc I6 is a motor that should produce more torque then HP...
The lower rpm you achieve max torque ( I max at 4250 rpm ), the faster the car will be.

Quote:

Originally Posted by RBYCC (Post 1882797)

Ok, but when using 2 turbos you only get half the engine pulses going to each turbo unless it's some kind of setup like in the supra's, which the mosselman and turbotechnics kits are not. I know it's like comparing apples and oranges but when my 2.5-16v was limited to .5 bars I used to have full boost also at 3000 rpm, later on I had 1.3-1.4 bars at 3500rpm and thats on a 4 banger runing a t3/t4 @ CR 8.0:1 .

P.S. it's all about the system design and turbo matching :-)

its all down to what it is u want from ur MERC, high power "drag" winner, single turbo is the way to go on account of being easy to work on later on (i think) but with the twins u get a quick spooling almost stock sounding car

Quote:

Originally Posted by JayRash (Post 1882976)

Point I wanted to make is , that with a properly size single turbo (targeted at the same boost and power) you will have the same response as with the twins, since this setup runs twins in parallel not sequential, slower spooling in single setups is dew to the use of bigger turbos in an attempt to make more power higher up ;) , the same will be true if you wanted to make more top end power on twins i.e. bigger twins = spool will become slower (in a parallel setup) .

Quote:

Originally Posted by Joreto (Post 1882891)

Ok, but when using 2 turbos you only get half the engine pulses going to each turbo unless it's some kind of setup like in the supra's, which the mosselman and turbotechnics kits are not.

Not sure what you mean by "half of the engines pulse"

With a twin turbo you have two manifolds with equal length runners...in essence two three cylinder engines.

Agree you can produce more power with one large compressor but you do not need to produce power at high rpm's in a low rpm engine...
The Merc I6 really doesn't do well above 6500rpm....

Historically Merc I6's have used twin turbos....

Quote:

Originally Posted by RBYCC (Post 1883123)

what I mean is that every other pulse goes to each turbo i.e firing order 1-5-3-6-2-4 so in a twin setup instead of all pulses going to one turbo they are split up, 1-3-2 -> in one turbo and 5-6-4 -> into the other so in essence you have half the pulses/power to drive each turbo .