Anyone done this. I am thinking about 4 degrees of advance in my M103 engine. I just wanted to see if anyone else has had good results.

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George Carstens

Your 103 doesn't have a woodruff key in the camshaft. It has an alignment pin. I have taken out the pin and had the bolt holes elongated with a mill to help out....

Remember, if you measure it using the crank, you have to calculate what you really want the outcome to be. The crank turns twice as fast as the cam.

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Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS

Fastlane has the keys made already. It tells you how many degrees of crank rotation and how many cam degrees.

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George Carstens

I bought a '73 450Sl and was checking the timing chain for stretch and found it was actually six degrees advanced, It is a new chain with new guides, don't know why it was done but it runs like a scalded dog(so to speak), Could you explain how this increases engine performance?? What actually happens? Thanks for taking the time to answer..
Chaosmosis

On some engines, if you advance the cam timing, you will increase the mid range torque at the sacrifice of top end power. When you advance cam timing, the intake valve opens sooner before TDC and the exhaust valve closes closer to BDC. There is an optimal timing for valves for maximum horsepower at every RPM. When you advance, on a lot of engines, you move this optimal timing down in RPMs thus increasing output usually in the mid RPM range. I hope that sort of makes sense.

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George Carstens

I don't guess you understand. The keys that I know of are for the cam gears of the V-8 cars. The 103 engine has NO key. So where are you going to put it>?????? It will not fit anywhere!!! Are you going to weld 2 v-8 cams together and then cut two of the cylinders off then machine a custom pulley for the chain to ride on??? (Of course I'm just razzzzing the hell out of you)

Seriously...There is no key on the 103 engine.

PS I looked in the catalog. Those are V-8 keys....They come up by default/. They will not fit a 6 cyl.

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Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS

The key goes in the crankshaft. The timing chain connects to the crankshaft via a sproket that slides over the crankshaft. This sproket is held in alignment by a woodruff key. They make more keys that slightly offset this gear a few degrees which you could effectively advance and retard camshaft timing, or if it makes it more clear, retard or advance crankshaft timing. The keys that fastlane sells tell you how many crankshaft degrees and how man camshaft degrees that equates to. Does this make sense?

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George Carstens

There is a company called DIAL-IN-CAMS which is now called LOGICAM, they made custom timing gears for me before for the M103. You could advance or retard the cams 4 degrees in 1 degree increments. The gears are $150. I can still have them made if you need. (need to check the current price)

I think I am going to degree the cam, figure out how it is timed right now, then move from there. I will probably have to dyno the car with different timings The gears, they made were fully adjustable to one degree? With the keys, I can only go 4 degrees or more. I can't go in one degree increments. It would be really nice though if I could change the timing on the cam gear without having to pull the engine out to change the woodruff key on the crankshaft.

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George Carstens

I guess, if the key will fit in the crank, you could do it like that. I have never seen anyone do this.

Hell, be a pioneer.

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Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS

I would think that setting the cam timing at the cam sprockets would be much easier and quicker. Plus you need to be able to set up a dial indicator on top of the valves, both on the intake and exhaust side to really know what the timing is at.

Opening the intake cam sooner can increase cylinder filling if during the valve overlap phase the exhaut pipe is doing a good job and because the valve closes sooner it is possible to get higher dynamic compression. And maybe more power everywhere, if you were getting excessive reversion before.

On the exhaust cam the closing point seems to be the most important timing. This is because if the exhaust valve is open too long you will start pumping intake air out the exhaust port.

And unfortunantly most of the above is trial and error work. Although once you get you first dyno run back, the torque and Hp curves will give some idea what direction to go.

Jeff