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Discussion Starter #1 (Edited)
I just finished the prototype performance headers for the M103 and M104 engines, take a look and let me know what you think. These are designed as a CAT forward package. 304 Stainless construction.




Header.JPG
 

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Nice. How about designing exhaust manifolds for the m103 to accomodate a twin-turbo setup? A modern-day turbo-techniks or mosselman setup with variable-vane wastegate turbos... I'm sure many forum members would be interested in that design exercise.
 

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Very nice work there. Keeps us posted on their performance. Also, fill out your profile so we'll know where you are located.

Jayare
 

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one thing i would say is the std six cylinder exaust configuration is done so that it keeps two seperate pipes, using cylinders 1,2 and 3 as one and 3,4 and 5 as another.

performance headders i have seen that are already avalible follow this rule, and keep all six primary pipes the same length, then the cilinders will all breath exactly the same.

i would redesign that manifold so as to keep that setup, as it produces better results.


that aside, nice work, they look really nice.
 

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Discussion Starter #5
my header project

The headers are 3 into 1, front and rear banks then 2 into 1 to the "CAT" . Important attention to detail include the final phase were the 2 into 1 collector transition uses a 3 degree angle of inclination to savage off as much exhaust as possible. The best effort were taken to produce equal length primary tubes and still fit this comfortable into the space allowed.
 

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they look real nice, you have done a wonderfull job. how long did it take to make them?

edit: in fact looking again at the picture, is that a cad image or the actual hedders?


in the uk, cars before 1990 do not have to have cats, on those vehicles mercedes kept the 3 into 1 seperate all the way to the back of the car, to gain the max performance. as far as exaust goes it is like having two three cylinder engines. turbo tecnics also kept that design, there are two seperate exaust systems to aid flow. i have not seen a cat setup, but i'm sure ed posted about two small cats in his system.

you guys are lucky in being left hand drive also, that system would not fit uk/jap/australian/cypres cars, our stering box is in the way!

how much have they cost to manufacture, what would you selling price be.
 

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Very nice! I'd like to have a custom stainless header for the OM606 (M104 might be the same design) with a single T3 turbo collector
 

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Discussion Starter #8
Time to go left handed, haha, this is the finished product ready to bolt on "prototype". We will turn this into a production unit selling for track and off road use only w/disclaimer. The OEM emission fitting will be installed but capped off and the O2 sensor bung will be there for obvious reasons. The "one off" was expensive but we hope to have units priced in the 1K range. It will work on 3.0L 12 valve 3.0L 24 valve and 3.2L 24 valve plus all AMG version of these engines. Even the 300SEL or SE can use them. Take Care.
 

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I would suggest for credibility doing a base line dyno pull followed up same day with a pull after header install.
Dyno doesn't lie and one can see exactly what the headers do to the power band.
If possible perform the pulls on a load dyno like a Mustang.
The load dyno will provide more real world power numbers.

Best to consider pulls for the M103 and M104 as the engines have very different characterics.
 

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Time to go left handed, haha, this is the finished product ready to bolt on "prototype". We will turn this into a production unit selling for track and off road use only w/disclaimer. The OEM emission fitting will be installed but capped off and the O2 sensor bung will be there for obvious reasons. The "one off" was expensive but we hope to have units priced in the 1K range. It will work on 3.0L 12 valve 3.0L 24 valve and 3.2L 24 valve plus all AMG version of these engines. Even the 300SEL or SE can use them. Take Care.
Ummmm....I'm sure you've considered this into the design parameters (correct?), but just bolting on headers without any attention to the exhaust valves can burn them without a cam change. How much the MB onboard computer(MAF) will compensate for the need for more fuel, I have no idea. Maybe the overall length of your headers makes them a non-scavenging type header? In a modern engine, scavenging headers can actually decease performance over the factory cast iron.

Increase in HP can only come from an increase in dynamic cylinder pressure. Most headers scavenge, which creates a 'suction' or a condition of less than atmospheric pressure. Therefore, there is no way that a 'suction' can create an increase in dynamic cylinder pressure. And then there's the whole issue of back pressure and creating more or less torque etc. I question any actual HP gains, but your headers are going to give off MUCH unnecessary heat. Open hood, show 'cool' factor is high though...:thumbsup:

I'd pay way more attention to how AMG got performance out of these engines, if you want to modify.;)

Kevin
 

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I watched one of those car performance shows on cable a couple of yrs ago. They put bolt ons to the tune of $1500 to gain about 7hp on a new Mustang. I think it was a CAT back exhaust system and a performance chip...but I'm not sure I'm remembering correctly about the bolt ons. However, they considered that a 'victory'...I considered it lunacy. For another $1500 they could have bolted on a under hood supercharger and really had something. Oh well....

As RBYCC said, make sure the dyno is equipped to simulate real-world load scenarios....the #'s will mean more that way.

Kevin
 

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Ummmm....I'm sure you've considered this into the design parameters (correct?), but just bolting on headers without any attention to the exhaust valves can burn them without a cam change. How much the MB onboard computer(MAF) will compensate for the need for more fuel, I have no idea. Maybe the overall length of your headers makes them a non-scavenging type header? In a modern engine, scavenging headers can actually decease performance over the factory cast iron.

Increase in HP can only come from an increase in dynamic cylinder pressure. Most headers scavenge, which creates a 'suction' or a condition of less than atmospheric pressure. Therefore, there is no way that a 'suction' can create an increase in dynamic cylinder pressure. And then there's the whole issue of back pressure and creating more or less torque etc. I question any actual HP gains, but your headers are going to give off MUCH unnecessary heat. Open hood, show 'cool' factor is high though...:thumbsup:

I'd pay way more attention to how AMG got performance out of these engines, if you want to modify.;)

Kevin
???????????

"Bolting on headers without a cam change can burn the exhaust valve"...Guess one can learn something new every day...

Please explain your theory behind that...

"Increase in HP can only come from an increase in dynamic cylinder pressure."
Something else I'd like to be clued in on !!!!

So how did AMG make power in the 320CE, E34 and E36 M103 and M104 variants?

P.S.

The M103-12V doesn't use a MAF as it is CIS injection.
 

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Discussion Starter #14
RBYCC,
Kevin doesn't like headers and that's OK, and I'm willing to follow up with the brilliant group that I developed this product with to double and/or triple check opinion like Kevin's to make sure we haven't miss something. It does propel me to new heights in the endless pursuit of performance mods. He is correct about the heat. We'll find a solution to control the heat. Trust me. BTW my pet project is building a M103/AMG, talk about expensive. $1300 in pistons $1200 in Con Rods, ouch!
 

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???????????

"Bolting on headers without a cam change can burn the exhaust valve"...Guess one can learn something new every day...

Please explain your theory behind that...

"Increase in HP can only come from an increase in dynamic cylinder pressure."
Something else I'd like to be clued in on !!!!

So how did AMG make power in the 320CE, E34 and E36 M103 and M104 variants?

P.S.

The M103-12V doesn't use a MAF as it is CIS injection.
The theory there is that scavenging headers will cause a 'lean' condition that can burn your valves in some situations as they create suction. If you notice, I didn't say "will". That's why different cams (at least on the exhaust lobes) are often recommended for many headers. It also gets more complicated with the degrees of back pressure involved in design headers, their length, going into a CAT system or open etc. It's very possible that going into a CAT system, lean burn is not an issue....that's what I was asking.

How did AMG make power in those model MB's, you ask(?), I don't know as I haven't studied their designs. You can play around with variable valve timing(to advance) and computers as well, for some gain. I also stated that if you wanted to gain hp in a MB, to study what AMG did. The statement, "Increase in HP can only come from an increase in dynamic cylinder pressure." is the basic principle in any basic hp building book or shop you care to mention. Where do you think the boost from your twin turbos winds up?? However as I said, how AMG did it, I don't have a clue. You're setting me up...I don't appreciate that, as I didn't write the book on hp gains.

PS As far as your m103 jab, he was talking about the m104 as well which does have MAF, correct?

Kevin
 

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RBYCC,
Kevin doesn't like headers and that's OK, and I'm willing to follow up with the brilliant group that I developed this product with to double and/or triple check opinion like Kevin's to make sure we haven't miss something. It does propel me to new heights in the endless pursuit of performance mods. He is correct about the heat. We'll find a solution to control the heat. Trust me. BTW my pet project is building a M103/AMG, talk about expensive. $1300 in pistons $1200 in Con Rods, ouch!
No, actually Kevin does like headers if they are wrapped (or coated) to reduce heat AND they produce real hp gains(and torque), for $1000, not just 7-10hp. Usually when you're working on one end like the exhaust, you're also considering the other end like the intake-porting & polishing, different pistons, different cams and using turbo or supercharging to get more air & gas mix into the cylinders to "increase dynamic cylinder pressure." I wish you luck with your project and I was just simply asking some questions, not putting my neck out to be chopped off. RBYCC is usually more congenial than that...go figure.

Kevin
 

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Discussion Starter #17
Kevin,
It is my hope that everyone interested in my header project will offer performance enhancement ideas to compliment the header side of the equation. Headers alone are not the solution to the performance gains we all seek but merely a component to that solution. Those with expertise in the field of modern automotive technology can contribute greatly to the ultimate solution. One only needs to write their own goals in advance and then pursue that goal with passion and determination and we will all profit from it.

Thanks for sharing, and as always when productive ideas come your way we all want to hear about them.

Tomson
 

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Kevin,
It is my hope that everyone interested in my header project will offer performance enhancement ideas to compliment the header side of the equation. Headers alone are not the solution to the performance gains we all seek but merely a component to that solution. Those with expertise in the field of modern automotive technology can contribute greatly to the ultimate solution. One only needs to write their own goals in advance and then pursue that goal with passion and determination and we will all profit from it.

Thanks for sharing, and as always when productive ideas come your way we all want to hear about them.

Tomson
Tomson,
That was my last point, thank you. Headers are just one component in a chain of modifying techniques to enhance performance. I agree that there are engineers out there quite capable of designing us bolt-ons to achieve 500hp on pump gas, if so desired on the m103/m104 engines. Of course there's always the question of cost versus practicality.

I come in here to relax, unwind, ask some questions sometimes and give some answers. I don't come in here to be put on trial, or defend the basic principles of engine performance building. I can just as easily use the search function, PM and lurk if it comes to that.

Again, best of luck in your project and I can't wait to see your results.:thumbsup:

Kevin
 

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i can speak from experiance for the 103 3.2 12v engine amg made it make more power by

1) installing 104 crank to increse displacement( used 102 rods and custom pistons) also raising compression ratio to 10.5 to 1

2) incresed the inlet valve size, and extensivly ported the head (inlet and exaust)

3)fitted a modded hight lift and longer duration cam, but as the cars were mostly autos, the cam was quite "mild" compared to what they could have made.

4) removed the hydralic lifters and replaced them with modded 2.3/2.5 cozzy ones and fitted uprated head gasket (300 quid to buy now, mercedes uk and germany had never sold one, they have now only ever sold one, to an idiot with more money than sence (me))(these were for reliability not power per say)

5) FITTED A PERFORMANCE EXAUST, but i am unsure if this was hedders or just system as my car did not have the original exaust on it, they are megga expensive

the net affect of these changes was 245 bhp as apposed to the std 170ish

this was achieved by the well known method of make the engine ingest as much air as possible, add correct amount of fuel and then compress it as much as you can, then set it alight at the correct time to allow it to be fully burnt at aprox 12 degrees after tdc! any sooner than that and you get pinking

do all this and you get more power!

the exaust only comes into play if

the engins exaust stroke cant force the exaust gas mass to fully clear the cylinder,
or it comes out of one cylinder and goes into another through the open exaust valve, due to too short a primary exaust.

Both situations leading to a reduction in the ammount of fresh air being ingested, so lowering the oxygen content of the cylinder, and raisng the temp, both of wich will make less power than optimum.

a good hedder will scavange, or suck the exaust gas mass out of the cylinder
but the effect of this on its own will be very small, and could in principle cause the engine to be lean if the fueling is then too low

hedders alone will give very small power gains if any at all, they are not magic.

hedders can make big difference to a highly tuned n/a engine.
 

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Tomson,
That was my last point, thank you. Headers are just one component in a chain of modifying techniques to enhance performance. I agree that there are engineers out there quite capable of designing us bolt-ons to achieve 500hp on pump gas, if so desired on the m103/m104 engines. Of course there's always the question of cost versus practicality.

I come in here to relax, unwind, ask some questions sometimes and give some answers. I don't come in here to be put on trial, or defend the basic principles of engine performance building. I can just as easily use the search function, PM and lurk if it comes to that.

Again, best of luck in your project and I can't wait to see your results.:thumbsup:

Kevin
Kevin

I'm still extemely congenial....too old to get excited about much of anything !!!!

No one is putting you on trial, I was merely asking about your theory of potential exhaust valve damage when using a tubular steel or SS performance header.

Damage to exhaust valves typically occur when you run an engine with no exhaust manifold/header or just a straight stack of pipes.
Not really the effect of scavenging but more the exposure to cooler air temp which will cause damage to the valve.

Couldn't agree more that tubular headers will cause a leaner AFR.
On older carburetor engines the AFR is fixed via jets or metering rods.
They tend to run stoichmetric +
The addition of headers with no other change will move the AFR to stoichmetric -.
Get the AFR in the 13 range on this type of engine and power will be made.

On a computer controlled engine the AFR feedback circuit will automatically adjust so you stay within a range that will not cause detonation.
The modern car will always benefit from a program change with or without the addition of headers.

No need to change camshaft as too much duration could cause the vehicle to fail state emissions testing.

I go back to the days when the headers were built on the car by guys like Jere Stahl, Sanders, Thorley and Jardine.
There were no computers to do CAD design, just a guy with a bunch of bends, tubing and a welder....and yes they made much horsepower.

Gain 7-10HP on a M103....that equates to a 7%-8% increase of power to the rear wheels...very noticeable.


With a turbo you don't need any scavenging effect from the exhaust as the movement of gas is inherent with the design of the turbo.

On a NA engine scavenging will produce power.
The design of the header should be such that it prevents the individual cylinder pulses from colliding.
A good design will use the pulse from the firing cylinder to scavenge the next cylinder in the firing order.

Kleemann makes headers for many of the newer Mercs.
Expect 7%-10% HP gain on an NA and 15% on a supercharged engine.


Honestly, I have never heard the term "dynamic cylinder pressure"...
What is it, how do you measure it, is it quantative, and how do you know if you have increased or decreased by making any modification ???


Ed A.
 
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