Blueprinting and stroking a m103 300E...
 

Hey, ive been looking around, and I was wondering if anybody has blueprinted their 300E or stroked it? I heard bekker's used to sell a stroker kit, but they said they don't sell it anymore, and didn't reply when I asked what parts the kit included. Ive heard of impressive gains by blueprinting american v8s, but I doubt German units would yield as much horsepower considering their stringent fault tolerances at production. Also, has anybody tried replacing their head gasket with a thinner one? Or perhas even new connecting rods for the pistons to increase stroke? These are all things that could be relatively inexpensive and yeild a boost in compression which equates to more hp....

The M103 is already at nearly one horsepower per cubic inch. That's a measure we used to use for race engines . I would tend to think any more increase would have to come from forced induction and/or fuel management. Just my $.03 worth. (inflation adjustment)

Yeah, I've run into this. I've looked for ways to improve performance, but most people are quick to point out that this engine is in no way significantly restricted. It was engineered with quality, so it's hard to look for simple upgrades. I'd like to get the mossleman, but for over 6 grand, i might have to settle with what i have for the time being...

Yea, I guess its just too bad... I suppose we are really limited by the sohc inline design, considering its what... 17 years old now? I mean, you got Acura making 200hp 2 litres, but they use all kinds of variable valve timing and intake... but, like I said, the engine is 17 years old, there must be something that can be done... Does anybody know if the head can be milled? Or perhaps where to locate the parts for the stroker kit? I mean, it was sold at one point in time, there has still got to be some connecting rods and piston heads somewhere!!!

Badinfo,

You would probably be better off just selling the 300E and upgrading to a 400E or a high mile 500E which can be found in the low $20k's. As many can attest to, this is the best bang for the buck in the long run.:)

Good Luck

no way... where is the fun in just buying a faster car? There is no uniqueness, no hands on labor, just buying a new title... if I wanted to do that... I would have been driving a shiny Supra right now ;) My parents would never let me sell the Benz to make way for anything, not even a 500, so that is definetaly out, but I can work on my car, and I have time this summer... I just need to find something to do!!! (And no, cleaning my car doesn't count, I do that every weekend thankyou)

Bring the car to me at MB Autowerks and I will make it run!

HMMMM Turbo and intercooler with stand-alone fuel management... HP would be about 400+

But, it would be big money.

awww, i would sooo love to stop by your shop... too bad im stuck over here in WA

hehehe.... turbos and intercoolers, yea, that sounds about right!! Hehe, now look at what youve done, im going to have to waste my entire summer!! :D

I am building an engine right now. I just bought a blow engine for relatively cheap and i know a guy who i am going to work with on the head. For the head, I am thinking bigger valves and just a port and polish. For the rest of the engine, it is being built for a turbo...I will lower the compression a bit, and put forged pistons and rods in. I am also working on desiging a better piston oiling system for the upgraded HP. Other than that, and lightening up the flywheel quite a bit, that will be my engine. Then i am just going to design a bi-turbo for it and see what i can put out with a custom fuel system and maybe water injection. So we shall have to see. I will have the engine dynoed and post up here eventually what i put out. Depending on how i feel about my 190E 2.3 8V and converting the engine to the M103 that i build, i will either keep the engine, or i will put it up for sale for all of you 300E and 190E owners to bid on. I will keep you updated.

are you going to have the rods and pistons custom made? or is there someplace that sells exotic application parts for this engine?

Turbo parts
 

I have a set of 8:1 custom forged pistons, and other parts too I ordered some fully ported cyl heads from Europe I have lot of friends there working with these cars. I also can make exhaust manifolds and other parts Please check my post for Fuel enricment and KE- Jetronic tuning, some free HP there, that tuning is almost necessary for turbo cars I am going to add more pictures there I build several custom turbo cars before. ;)

As far as I know, and I could be wrong, is that the 3.6L stroker conversions done by Brabus and RennTech on this engine involve using a crankshaft from the 350 diesel engine. I don't know what the rest of the configuration is though. I do know these guys get ~$13k for the job. The 3.6 M103 puts out nearly 275hp, not bad for a 2 valve sohc.

Good gugally-mugally!!! Is it supercharged? :eek: :eek:

G-man
 

:eek: G-man is that crankshaft from GM 350 Diesel is that little bit too wild, there is no way to fit somethink like this V8 crank for srtaight 6? I have seen stroke kits for sale includes piston set they customice your old crank, they add metal outside of connecting rod journey, and grind of opposite side, means more stroke. Price was about $2000 but that is just the start for the process, then you may have trouble with connecting rods, also have to port head, bore the block and Etc.. But I like to do that

I also heard 350 diesel crank and con rods from a C280 would give you a M103 stroked to 3.6... Fact or fiction?
Adam

CORRECT ME IF I AM WRONG
 

Hi guys,

Does a GM 350 has different bearing arrangement compared to M103:confused:

I think AMG has a 3.2 stroker kit

Trying to fit a 350cu.inGM engine crank in a M103 engine is as easy as trying to replace your headlight wiper motor with a Boeing 747 engine.
The only communality between a 350 crankshaf and a 103 crankshaft is the name.
Forget it. It has never been done, will never be done, it can't be done
jackD

you sure they mean a GM 350 Or a Mercedes 350 Diesel engine.

I thought they were talking about a mercedes diesel engine from a 350 diesel model...

Alon

Jackd and chupr98,
Yes, a GM crank would be pretty hard to adapt to any Mercedes engine. Thats not what we are talking about though. The crankshaft in question comes from a 350SD-SDL which recieved the 603.970 engine. The M603 diesil engine is an inline six with 3.5 liters of displacement. Theoretically, when combined with con rods of the C280 it is capable to achieve 3.6 liters of displacement in the M103 engine.
Hope this helps!
Adam

Is it as easy as it sounds? do you just take the connecting rods from the C280 and the crank from the 350SD-SDL and bolt it all up, or is some hard work involved. Wouldn't the timing gear have to be replaced as well or is this not a problem. Has anyone in these forums tried it?

Mr Chupr98 was really talking about a 350GM engine, pls. re-read his post. If this is the case, better forget it.
If you are refering to a 350 Mercedes diesel crankshaft, my spec book give different crankshaft journal diameter and width. Installing 280C con rod on this crankshaft would require major machining surgery and pssibly engine block machining as well. I don,t have specs on the lenght of the 350 crank lenght so it might require stretching/cutting, which is generally not within a backyard mechanic capabilities.
Anything can be done (almost) but the results are sometime not worth the efforts (read $$$).
A transplant with a 5.0l from a 500E might be easier/cheaper to acheive.
JackD

I never said it was easy.
Well, the guy I recieved the info from may be completely rong or partially rong. It dosn't hurt to do the research.

Jackd,
Since you have these technical manuals on an assortment of Mercs, check and see if any other con rods will work or would be easier to adapt to the 350 crank. Inline 6 or inline 4, check it out!
Thanks!
Adam

Jackd,
BTW: Do you mean 280C or C280?? there is a big difference in engine config.

Bad info. If your interested. My friend has this kickass head for a 103 engine from the late 80's I belive its a brabus wiht big valves ported and polished heads,with a nice brabus racing cam and Valve cover. The thing just sites in his garage. I know he wants some serious money for it. Its brand new I think from what he told me never been ran. That would be a big improvement to this 103 engines. I had a 300 last yr before i got my 500. Let me know.

How about posting a price on the Brabus head?

3.6L M103
 

The M103 AMG 3.6L is a stroker crankshaft which is a BRAND NEW crank that has been reground to 93mm instead of the normal 81mm. The bore of the engine is increased from 88.5mm to 90.5mm. You could buy a brand new unground crank from AMG but the price of the machine work would not make it worth it. AMG could still do the machining but the price is in the $6000 range. I have been using welded strokers for years in BMWs and VWs. The Mercedes would be the same. The material content of German crankshafts are really good with a high nickel content that usually makes them very hard. A welded stroker crankshaft for a 6 cylinder is about $1500.00 and a brand new USA made 4130 Chromemoly crankshaft is about $3500-$4000. 90% of the 4130 crankshafts that are sold are made in the USA! and used by major race teams and engine builders. They are exported and then sold back to users in the US who think they are buying a HIGH QUALITY foreign made crankshaft!

Of course in using a stroker crank you will need to use special pistons or shorter rods and those can also be made.

There are a lot of horror stories about welded strokers but that is usually done by a bad machine shop or someone who did not know what they were doing. A lot of engine tuners use welded strokers and charge the customers BIG $$$ for them. some of them are really hard to tell it has been welded. On the good crankshafts the welding is specially done. then the crank is xray-ed to look for air bubbles or cracks. then machined. sometimes sandblasted or shotpeened. and Nitride Hardened treated.

I have used stroker cranks in engines that rev to 10,000 rpm with no failures! In fact I have never had a failure in any crankshaft that was welded to my specifications. or done by a machine shop that specializes in this.

Also the longer the stroke the lower the peak torque RPM.

example: (not exact)
80mm stroke = 7500 rpm peak torque
88mm stroke = 6000 rpm peak torque
93mm stroke = 4500 rpm peak torque

Sorry for the long post but I just felt the need to educate people in this very misunderstood area of engine tuning. If you feel the need to redesign an engine let me know!

Thanks a bunch Speedtek, your post really did clear up a lot of confusion! It looks as if strokking the m103 engine just isn't worth it when you consider a turbo setup (thanks to you Speedtek) can be had for $1k, and the turbo will probably give you better hp results.

Ok, were making progress here. But I think the issue of whether or not the 350 diesel crank will work in the M103 motor is still in limbo.

Also, the M104 motor displaces 3.2l, would this crank work in the M103 block as a option.

I too am exploring stroking the M103 motor, but if a viable alternate can not be found, I will be sticking with the 3.0l displacement and using a highly modified head/cam/header package.

According to my references, a Mercedes 350 camshaft has different journal diameter, is longer, uses a different timing gear, the distributor set-up is different and lobe configuration is also different.
Converting this cam to a 103 engine would probably be more trouble (cost) than building a new cam shaft from a raw piece of steel.
And forget about the 350GM cam. It is a totally different beast.
The best and chapest way to improve performance on a 103 engine is bring it up to specs on eveything and to get rid of 1000 pounds off the car.
Good luck
JackD

ahhh... but a w124 sans a thousand pounds is no longer a Mercedes, I believe they call those Chryslers...

When did camshafts come into the picture? I thought we were talking about crankshafts.

getting stroked!
 

One of the best strokes is 86.4mm. If you are turbocharging stay with the stock bore. that will come out to 3189cc almost 3.2L. If you plan to go Natrually Aspirated, I would suggest boring the motor to 90mm, which would bring you to: 3298cc or 3.3L

SUMMARY: 300E M103 Engine
88.5mm x 81.0mm = 2990cc STOCK
90.0mm x 81.0mm = 3092cc Overbore
88.5mm x 86.4mm = 3189cc Stroked
90.0mm x 86.4mm = 3298cc Overbore + Stroked

There is also a way we could offset grind the crankshaft to get it to a 83.0mm stroke and cost under $300. This would greatly increase the low end torque. You could still use the stock rods and take a stock set of pistons and machine the top of the piston a little. This will give you higher compression without spending a lot of money. I could machine the pistons up to 10.8 to 1 compression and as low as 8.5 to 1.

88.5mm x 83.0mm = 3063cc

I estimated the cost to do all this PLUS rebuilding the block to be in the $2200.00 range with NEW OEM pistons. That would not include rebuilding the cylinder head.

89.0mm x 83mm = 3098cc
Compression 10.5 to 1

Estimated HP: 197 HP @ 5600 RPM
Estimated Torque: 215 lb/ft @ 4400 RPM
Estimated 1/4 mile time 15.8 Seconds

Figures are based on using a stock camshaft, 1989 USA Spec 300e car as standard. Stock 1/4 mile 16.4 sec. Automatic.
I have come up with higher HP figures using a small camshaft &
exhaust:
Estimated HP: 220 HP @ 5800 RPM
Estimated Torque: 238 lb/ft @ 4600 RPM
Estimated 1/4 mile time 15.4 Seconds

I know everyone might have slight differences but I am using these figures as a guideline.

damn, all i can say is i wish Speektek was my neighbor :p
id always be running over and bugging him to do something with my car to make it go faster :p how much fun would that be?

thinking of moving to hawaii.... :D

Is this stroking article of any use? (no pun intented) :D

http://www.hotrod.com/editorial/article.jsp?viewtype=text&id=69883

Speedtek,

How about a 6 psi Powerdyne on a stock M104 E320 motor. Any problems.

HP?

OR-

9 psi on a 3.6L stroked M104 w/ 9.5:1 compression.

???

Speedtek...how much do you have to shave off of the stock pistons to lower the compression to 8.5?