08 Camshaft vs. 09 Camshaft

[TheEngineer]

Reading the BBB because it's raining: For the 280SE the camshaft is marked 08 and for the 280SL it is 09. The difference is a few degrees in valve timing. Is there also a difference in valve travel? Is the 09 cam for european models? I checked my camshaft: 08 is engraved on the face at the rear end. Dan Carron once commented on using a 230SL camshaft, because it is close to "a performance camshaft of the 280SL". Anyone out there who can educate me?

[Benz Dr.]

It's the duration or time the valve is open ( stated in degrees ) which is similar to the 230SL camshaft. Moving the valve timing ahead ( using a woodruff key ) about 3 degrees closely matches the 280SL euro cam.

Dan Caron's
 SL Barn
benzbarn@ebtech.net
 slbarn.mbz.org
  1 877 661 6061

[TheEngineer]

Thank you Dan for the attention. Please clarify:
Is the valve lift the same of the 08 and 09 camshaft?
What is the number on the 230SL camshaft?
I did use an offset woodruff key: P/N 621 991 01 67 Offset 1.1 m/m or 4º or 8º (KW)measured at crankshaft, but only to compensate for chain stretch and cylinder head being "surfaced" excessively.
Is the 09 camshaft the 280SL euro cam?

[ja17]

Hello,
The #09,  #02 (both 280SL) and the #76, #84 ( both 230SL)are the hottest cams, the 230SL cam is a bit hotter due to more advanced timing, but would require other changes (cam holders and it has narrower lobes). These four camshafts have a total "valve open" duration of 142 degrees each.

The #08 is a poor substitute it has a total valve open duration of 122 deg (about 20 degrees less). Cam #11 and #86 at 132 deg. are the better choice over the #08 at 122 deg. Cam #01 and #05 are  a bit better than the #08 at 130 Deg.

Camshaft numbers #04, #08, and #61 seem to be the mildest at a total of 122 deg.

I have compiled a camshaft chart with specs on over 50 Mercedes camshafts. For some reason it will not paste on here so email me for a copy if you like.
   
Joe Alexander
Blacklick, Ohio

[Ben]

Guys what is the best way to achieve best or ultimate cam timing ? I realise a dial gauage and offset key would be required but if someone could run through the procedure I'd appreciate it !

Regards,
Ben in Ireland.
'64 230SL 4sp.

[TheEngineer]

Hi Ben:
To me the "ultimate" cam timing is, what the book calls for. The procedure for checking valve timing is described in the BBB and absolutely requires a dial indicator: First, you eliminate the valve clearance by inserting a feelergage which is thicker than the existing clearance. Then you set up the dial indicator on top of the spring retainer, so that it shows you any valve movement. Then you turn the crankshaft until the valve starts to move down and continue until it has moved 4/10 of a m/m. That is your starting point. Look at the position of the crankshaft: It should be at 11º before top dead center (for a 08 cam). If it is not, your chain is stretched or your cylinder head sits lower than designed and you should correct the camshaft rotational indexing by using an offset key. I have seen one engine where the timing was off by two teeth. One tooth is about 18º. If the cam timing is early, the intake valve opens too early and touches the piston before the piston has moved down. Bad News! The closest approach between piston and valve is at 5º after top dead center. Therefore, move the crankshaft to that position and push down on the valve: You should get a minimum of 9/10 m/m. Different cams result in different valve timing sequences which affects engine performance.

[Ben]

Thanks so much for the information !

Last question............I promise..........mine is a Euro 230 so are the figures the same ?

Where can one get an offset key ( see I lied about that bneing the last question) Is it a Merc part !

Regards,
Ben in Ireland.
'64 230SL 4sp.

[TheEngineer]

I'll trade you an offset key for a 09 camshaft. I got the key from Siegfried who is retired and plays with old Benzes, but it is a Mercedes part and the P/N I posted comes out of the BBB

[A Dalton]

B

 SLS has tham in five different degrees..

 Go to Head Insert and click on item # 33....

 5 Euros ea.......

[ja17]

Hello,
 The offset keys should still be available from Mercedes. The part numbers are for (4 deg. 621 991 04 67), 6 1/2 deg. # 621 991 02 67), ( 8 deg. #621 991 01 67) and (10 deg. #621 991 00 67). These are universal to almost all their engines of the era.

Joe Alexander
Blacklick, Ohio

[Ben]

Great stuff..........thanks guys !

Regards,
Ben in Ireland.
'64 230SL 4sp.