High engine RPM?

[n/a]

I just took my '65 230 SL 4 speed on the freeway for the first time.  I've had to do some repairs to get it going, but it seemed to be running well, so I gave it a shot.  It felt great, but it seemed that the RPMs were really high.  I believe the tach showed 3600-3800 at about 110 km/hr (about 65 mph).  Is that about right?  Perhaps I'm so used to the low rpm of my Chevy truck that I'm just a bit nervous.  Thanks for any input!

1965 230 SL Euro 4 speed (me)
2004 230 SLK Kompressor (my wife)

[n/a]

My 65 230 SL automatic is also rather busy on the highway. My car does about 3,000 revs at 60 MPH and 4,000 at 80. I suppose it depends on a number of factors such as diff ratio and tyre size. I don't believe that high revs will hurt these motors, it's what they were designed for.

Mark Ravagnani

1965 230 SL light blue, auto, RHD

[knirk]

The rpm / speed ratio is probably correct. From the MB BBB a 280 sl (230 sl not listed in my book) with 4-speed transmission and a 3.92 diff ratio should have 3.340 rpm at 62 mph (100km/h).

Per G. Birkeland
69 280 sl aut 834
Norway

[n/a]

Thanks for the input.  I feel better knowing that the car is in range of where it should be.

Dan H

1965 230 SL Euro 4 speed (me)
2004 230 SLK Kompressor (my wife)

[Cees Klumper]

I read in the 190 SL Group's most recent newsletter that normally (if you have the correct differential, tires and speedo set-up) the speedo and tach needles will move in unison (be at the same position on their respective dials) in top gear (4 th except when you have the ZF 5-speed, then it does not work). On my -originally US- car, the MPH speedo was replaced for a KM one and it read about 5-10% too fast. Then, after I replaced my rear differential with a 3.69 (down from the original US-spec 4.08) the needles do move in unison and the speedo is accurate (AFAIK). Which means the engine turns a bit over 4,000 RPM's at 120 KPH. When I first drove my -automatic- car, I thought top gear was not engaging because of the high revs. Now I've gotten used to it and notice how you will be driving extremely fast before you ever hit the redline in top gear ...

Cees Klumper in Amsterdam
'69 white 280 SL automatic

[n/a]

Cees,

Since you mention it, that is about right on with my car.  I took it out on the freeway again today and was doing 110 KPH at about 3700 RPM and both are just to the right of the top on the gauges.  That's a good thing to know.  Now that I'm used to the high revs, it's really a lot of fun because the response of stepping on the gas is an instantaneous rush of power to hurl you down the freeway...



Dan H

1965 230 SL Euro 4 speed (me)
2004 230 SLK Kompressor (my wife)