Euro cam; performance improvement?

[TR]

I have recently come into possession of a new European version camshaft.  It is an 02, and at some point in the future will replace my U.S. version 05 cam, which came with the long block from Metric.

A question for those who have already made this change: Were you able to really sense, or better yet actually measure, an improvement in power/performance?  Has anyone done a before & after dyno test?  And if not (probably not) were you able to clearly "feel" the difference?  If so was it particularly noticeable?  Or was it just barely perceptible?  I'm guessing, and certainly hoping, that it was obvious & noteworthy.  I'm curious since it will probably be some months before this change will by made to my '71 280SL.

Tom in Boise
'71 280SL 4-spd, signal red w/lt. tan interior, restored/enhanced

[Richard Madison]

Tom:

Not sure this will help as it is just my subjective opinion but:

I owned a 1971 USA version 280SL for about 5 years. The car was adjusted and maintained by an experienced mechanic, a specialist in old Mercedes. The car ran very nicely and I was quite satisfied with its performance. I'm not a speeder or a racer but the car accelerated nicely and seemed happy even at the rare times I flirted with 80 plus miles an hour.

Now I have moved on to a Euro version 1969 280 SL. The engine is adjusted and maintained by the same mechanic so maybe a fair comparison of the two cars can be made.

Both cars have been driven by me and by the same fellow Pagoda owner. We both noticed that the Euro car is more eager to go and much zippier than the USA version.

Can't say if other factors are at work,  but at least to me (and my friend) the Euro car is a hotter car with noticably better acceleration.

I sometimes call her "Ol' Beige"...but Ol' Beige runs like a young stallion.

Richard M, NYC

[TR]

Thank you Richard, that is indeed helpful.  Noticably better acceleration, i.e., more oomph, is just what I'm looking for. Although I don't normally drive my car hard either.

In addition to the Euro cam my car will likely also end up with an earlier version 280SL distributor, which your car should have.  The thought/hope is that between the Euro cam and the earlier version distributor that my late-model 280SL will then deliver more snappy acceleration, and would be closer to what the M-B engineers had originally designed.

When these changes are made I'll try to have before & after dyno testing done.  It would be nice to quantify any power gain.

quote:Originally posted by 280SL71
Can't say if other factors are at work,  but at least to me (and my friend) the Euro car is a hotter car with noticably better acceleration.

Richard M, NYC

Tom in Boise
'71 280SL 4-spd, signal red w/lt. tan interior, restored/enhanced

[Ziggy]

As far as I understand, in general the performance curve moves to higher revs when using a hotter cam. This would mean that you would have less performance at lower revs. Isn't this the case with the m130 engine?
I would like to get a cam 10 or 20 degrees hotter. Wouldn't it affect performance negatively when driving under 5000 revs?

[Benz Dr.]

20 degrees hotter cam? Can't be done.
 Just like you can't overheat these things and expect them to keep running.

[Ziggy]

The 08 has a duration of 122 degrees, the 02 142. What do you mean exactly?

[Benz Dr.]

Duration can be plotted on a graph and shown in degrees but I'm talking about timing. You can't advance the can 20 degrees or the intake valves will hit the pistons.
You need a minium clearance of .9 mm at 5 degrees ATDC on the power stroke. That's very close and it doesn't leave much room for mistakes.
I have the results from a flow bench test on an old 250 head ( not cleaned up and full of crud ) and the guy who did the test was very impressed. He said it flowed more than the average small block Chev engine. So, flow isn't the problem but you can make it better.

What too many seem not to understand is that these engines are high performance right out of the box. They produce about 1 HP per cubic inch which isn't bad at all for 40 year old cars. What we have here is a car that's all metal and it's kind of heavy despite the alloy panels. Then you have a pretty small engine spinning at high speed producing lots of power for its size. What's wrong with that?

My car is as fast as most 280's but it has a 250 engine in it. It also uses 10 liters per 100 KM and it will run on regular. This can only be done using specific engine parts and machining techniques.

[Ziggy]

Thanks for the explanation Benz Dr. What I meant with 'a 10 or 20 degrees hotter cam' was replacing the 08 cam with a 11 or 02 type.
I was wondering whether you would lose power on lower revs with such a cam.
I am interested to know what you did with your 250 engine. Is there a topic somewhere about that?

[Benz Dr.]

There migt be some info scattered throught the site but most of the really trick stuff is inside my head where it will likely stay.

I'll give you a general outline of what parts I used:

*I started with a 250SE engine from a 111 coupe. This is the same engine used in a 250 SL.

*I used all new valves, guides, rockers and springs.

*All bottom end parts are new but I used a late oil pump because I used the oil pan with the ribbed bottom. This pan has a windage tray to pull the oil away from the crank and is a little bit deeper.

*The cam is out of a 230SL which has fairly good timing and it has the same specs as a euro 280 cam. I had to advance the cam timing 4 degrees to match the euro cam so it opens right around 12 degrees BTDC.

*I used early exhaust headers which are wrapped in heat tape. This holds the heat inside of the pipes and out of the engine bay. Hot gasses flow faster than cooling gases which produces more manifold vacuum.

*I also replaced the flywheel with a 280SL unit and put a 280SL pressure plate in because the 230SL unit would slip with that much power.

This car has a 5 speed ZF trans which I rebuilt.

*I used a dual point distributor from a 300SE. This is a true dual point system and the cam only has 3 lobes and each set of points runs 3 spark plugs. In its day, this was as high tech as you could get and it's still a very high tech unit. A normal 051 until runs at about 38 degrees of dwell - this one runs at 52 degrees of dwell which give a much hotter spark due to longer coil saturation. All the advance movements inside run in a ball bearing cage. The advance movement is very precise. I topped this off with a red coil, ballast resistor and new wires.

* All lubes are full synthectic including the power steering.

* visco fan clutch.

How I put it all together and what machining tricks we used is the stuff I won't tell you but I will say that it took a long time to do. The head was put on a flow bench to see where we were going.

[Ziggy]

Thanks for sharing that, this is certainly very interesting. How much extra HP do you estimate your engine has above a stock m129?
I would have never thought of using heat tape. Might try that as well.
Does installing new valve springs give an improvement?

[Benz Dr.]

I figure 10 to 15 more HP. I'd have to put it on a dyno to know for sure. The first 170 HP aren't that hard to find, everything above a certain amount takes a lot of scratching.
New valve springs are not exspensive and keep everything ballanced.

[pago41]

I don't mean to make a hot rod out of these wonderful engines, but is there not a way to tune and modify the engine to put out 20-30 more HPs and more punch? Something like what AMG used to do in the early days of tuning for Mercedes. There is a great humorous video of Jeremy Clarkson of Top Gear test driving a 113 in which he calls the down shift from 4th to 3rd only a switch that raises the noise level! At one point he is so proud to reach 65 mph on the motorway. He is driving a British pagoda. Check it out on the Youtube.         Happy motoring

[Benz Dr.]

There's a way to get that much HP. How much are you willing to spend? 'Cause it won't be cheap....

[JamesL]

Pago

As a Pagoda driver, I think Clarkson had A point but around that time there was a discussion on here - or maybe the UK MB club - about that car. The owner had all manner of trouble with it including the kickdown/pickup...

However, it's clear that the engine is a well built unit with - in it's day - very high tolerance for revving and running all day. So with some modern tweaks, you'd think there should be more in it than there currently is. Not that personally I think it needs it

[pago41]

Thanks Dan, i don't have a set figure in mind, but if i was rebuilding my engine, i would go as far twice the amount to get that much more horse power. On another note, back in the eigthies i think, there was an article in one of the issues of the Star about a 280 SL with a 3.5 Mercedes engine conversion. The article mentioned this would have been a natural evolution of the 113 chassis had the factory decided to continue production after almost eight years. Does anybody what happened to this car and what mechanical issues had to be addressed to allow such conversion?                     Best

[glennard]

'Hatch' in the Boston area has done a lot of these conversions.

[seattle_Jerry]

The conversation ofgenerationg morpower always amuses me.e it on bicycles or cars...its always about horsepower to weight. I'm willing to bet that the easiest place for our cars to lose weight is around our stomachs.

Its like a 30 pound man on a bike. There is one obvious place to shave weight cheaply before goingout and spending a fortune on titanuim parts.

Lose the spare tire figuratively and literally. Who has blow outs? They are so rare.Carry fixaflat and an auto club card. Your trunk should be empty.

Gas weighs 6.5 lbs a gallon. Depending on your tank size you save 50 lbs by only running a half tank.

But ultimatly it doesnt matter because our car isn't a performancecar. There are pleny that are faster. Ours is fastish with style

[Benz Dr.]

I saw that article about how they installed the 3.5 engine in the 280SL and it was quite a bit of work but it looked good when done. The biggest problem they had was around the trans and all the clearance problems.

I have a good 3.5 engine and trans. Hummmm....

[Tom Colitt]

Hi Pago41

I read your post and you might be interested in my thread about my 280SL /3.0 M130E project that I am currently developing (also in the R&D section). I also am about to do comparative HP tests between this 3.0l engine with and without the European camshaft....

I feel that I will be able to offer a complete long block engine rebuild, including the custom ground and heat-treated crankshaft, custom pistons and rings, balancing and the cylinder head for about the same cost as a rebuild by Metric Mechanic.

Regards, Tom

[pago41]

Thank you Tom, I would very much like to hear more about your final results and HP ratings with stock and Euro cams.                    Best...Pago41

[hauser]

Here's the info for the 3.5 project cars.

I had the opportunity to speak with Bob Hatch about the SLR 3.5 and he said it handled better than a Ferrari.

http://hatchandsons.com/pages/280sl/

[cospinner]

In the December 2008 issue of Hemmings Sports & Exotic Car, there is a good article about both of the 280SL 3.5 cars that Hatch and Sons converted, with associated pictures.  Very interesting.

[Tom Colitt]

Okay. I was going to install the Euro specification cam that I had reground using an original 02 cam as the master. The problem is, I measured the lift of the re-ground cam and the numbers are slightly less than the Euro (02) cam for both intake and exhaust lobes. They are also slightly less than the lift I measured on the "01" US spec cam that was originally in my engine.

I have the camshaft chart that Joe Alexander put together, but unfortunately it does not show any maximum lift values. My question is, does anyone have the specs. for the lift of an 01 and an 02 (or 09) camshaft? The new factory 02 euro cam that I have measures about 7.2mm lift on the exhaust lobes and 7.65mm on the intake lobes. The 01 cam measures slightly less at 7.5mm for intake and 7.0 for exhaust lobes. Of course the timing and duration for these camshafts would contribute to the performance differences as well.

My re-ground cam also delivers 7.5mm on the intake side and 7.0 for the exhaust lobes. The camshaft specialist argues that the engine would never know a difference of only 0.2mm. I am not sure I want to go to the trouble of installing it in my test engine to find out whether there is a change in performance (any change could only come from the different timing of the lobes, since the lifts are more or less the same.)

Does anyone have any number, either from literature or accurately measured, that can help me get an understanding for the expected differences between the 01 and the 02 cams?

Thanks, Tom