How can I increase the 560SEL 1989 performance?
 

I did the followings:

1. Changed all of the spark plugs (Bosch) and their wires (Beru).
2. Cleaned the fuel distributor professionally.
3. Changed all of the filters u can imagine in the car.
4. Made sure that all of the car electricity r poperly fine.
5. Changed the engine chain and some other parts.
6. Made sure that the chain timing is fine.
7. Made sure that all of the 8 injectors r working properly.
8. Always using original 15/40w oil.
9. Made overwhole for the transmission.
10. Kickdown alignment is fine and working.

The car looks fine but I still don't get the performance I wanted like with my 560SEC 1989.
What else I can do? Please tell me : ))..

Is this a US car or Euro?

If US you could always drop cash for the true duals from the Euros for some better power. Also first gear start would be nice too.

There also was a recent thread regarding how to turn up WOT fueling from the CIS unit then adjusting the AFM and CO accordingly. As soon as my 420 starts up and runs, I'm going to adjust it.

well
 

it does weigh at least 200# more than the coupe. probably more. so it wont feel as quick in acceleration nor on top speed as the coupe is slightly lower and will have less wind resistance.

relax, this is the limo version, the coupe is the sporty version.

that said do you think it is running right? if not sure, did your plugs look the right color when you changed them? all the same? smooth idle? personally i wouldnt monkey around too much. you might be able to advance the spark a little beyind factory. as noted above euro duals might help, but you prob will come close to that by removing the rear muff and puttin on a custom straight pipe like i did on my 500sec. a little less backpressure and you can hear the big v8 rumble.

good luck, sounds like a nice car.

tom w

the Only cheap means of getting more power from your car (once everything is in proper order) is replace the spring loaded portion of the throttle linkage w/ a solid bit, remove the ignition reference resistor (takes initial timing from 3 to 12 degrees initial) and drop in a K&N (I find the 560's a bit starved for air on the dyno).

After that it gets expensive, i.e. exhaust, cams, head work, forced induction etc, etc...

Jonathan

Does the same go for 420s for the resistor and throttle linkage?

I know it will not be a rocket but increasing timing on my F150 from 10° BTDC to 15° picked up around 12-13rwhp alone. So if I can bump that and increase WOT fueling I could potentially see an easy 25-30rwhp no sweat.

Well, you won't see That much of an increase, fixing the linkage/resistor/air filter on my 560SEC w/ fresh heads and Euro Tri-Y manifolds (check my page for pics) I found about 9 RWHP.

That aside, yes these items will work on your 420:)

Jonathan

Ah as I figured they're pretty much maxed out stock minus the WOT fueling end. My Ford ran lean stock (~15.2:1!) and only had around 30° of total timing.

Did you dyno the resistor change to see if the car picked up any significant gains in the midrange from 2000-4000?

Well, the resistor did wake things up nicely up to 2500, more power sooner etc..after that timing is no longer controlled by the reference resistor. I didn't have data acq. on during these runs (car will be set up for 2 O2 sensors somewhere down the road) so I don't know what A/F ratio I was running.

I've also found giving the EHA a turn one flat to the right helps a touch as well.

Jonathan

Excellent, thanks for the info. :)

My pleasure..! Good luck w/ it.. I take it you know where the resistor is? Right next to the fuse box towards the passenger side..bunle 'o wires.. Will be a small plastic square w/ 2481 in white number..big giveaway is the electrical tape around the bottom of it.

Jonathan

I believe I saw it there, similar in location to my chums 300E. Once it drives I'll have to report back. :D

It's Euro specs.
Smooth idle.
Spark plugs were fine before I changed them.
Exhaust system is fine.
And it doesn't have springs bucause it has 4 wheel hydraulic system.

So nothing else could be done?

lots more can be done...it's just a case of how much do you want to spend. Do you want hot cams? Forcecd incduction (super or turbo charged), full exhaust, headers, diff, transmission upgreades etc.. Everything is doable for a price!

Jonathan

What I want to do is only tuning the car without installing parts.

I want it to be as poweful as new : ))..