Where does this hose attach to? '88 300SEL
 

Coming from the air cleaner top.

http://www.fototime.com/708B462BDCC79D4/standard.jpg

Pull the air cleaner and you will be able to see where it goes. Kinda behind the dip stick, under the air cleaner.

That should connect to the fuel pressure regulator vent line.

OK thanks. It runs fine the way it is. When I reattach it, will I feel another 50 horses when I step on the gas?

:beer: NO

Damn! I'd settle for 5.

Sadly you would not notice 5hp.

So how different is the drive between your 300SEL and 560SEL? About 177HP vs. 230 or so but more weight.

Well the 560 has around 90lb-ft of torque more, about 1000rpm sooner. The difference is night and day. It can accelerate with ease at 2000-2400rpm while the M103 struggles down there. Fuel economy between them is very similar too, I also poke around town in 3rd gear with the M117. Weight difference is minimal as the M117 is an aluminum block while the M103 is iron.

The M103 is a fine motor but it really does not belong in the LWB and should have been offered with a five speed manual. 300SE + five speed manual would be fun! :) The M103 + W126 is also geared totally wrong with the second gear start and 3.46:1 rear diff. First gear start and 2.88:1 seems like a happy medium, about 3000rpm @ 70mph.

My 735i with a manual is a totally different drive.



If you have never done a valve job on your M103, you are losing noticeable power there. I finished mine up in January or so and the difference is nice. Power is more linear... mine has 280k on it.

Yes it's no rocket but it's the same engine as in the 300E and really only weighs maybe 300 or 400 pounds more than the E. The weight of a couple of passengers. Perfectly adequate.

Actually I do have a 5-speed S-class but in the newer W140 body and with the C280 engine.

Could be slower. The W126 was offered with the M103 2.6 engine in some markets. - 260SE

Your loose hose plugs into this FPR - closest to the engine block
http://farm4.staticflickr.com/3650/3...65d_z.jpg?zz=1