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Is "feathering the throttle" common for automatic drivers?

Started by Ilike300sd, 28 September 2011, 09:32 PM

Ilike300sd

The seller told me the guy he bought it from told him to 'feather" the throttle.  This means, as I understand it, to not mash your foot on the accelerator but instead let off a bit before it shifts.  Is feathering the throttle a common practice?

Tony66_au

I do it in the 230TE, I back off just before she is about to change and get a smooth shift.

Why?

Because I cant be arsed adjusting the kickdown and because the Auto is a but tired and abused (From before I got the car which is a great example of how NOT to "Fix" stuff)


Tony66_au

They tend not to get past the rear 1/4 on the wagon before the mysteriously disappear in a cloud of foul language and broken glass with a slight "Bump" for effect.

I know not why but i keep getting the weirdest urge to buy a Moped stencil..........................

Actually I live right on a highway and the wagon does ok launching out of the driveway.

jbrasile

Ilike300SD,

I got used to doing that on my 79 300SD. With a diesel you are actually controlling the amount of fuel injected in the engine with the gas pedal, you get more control than with a gasoline powerplant where your foot opens and closes the air, not the fuel. Also with a turbo diesel if you feather the throttle and let the engine build some boost you get more power going up hill for example than if you just floor it. It is an interesting technique that gets better with practice.

Yes, shifting does get smoother but if the transmission is slipping you have to know when to ease off the pedal to make it shift more positive.


Tks,

Joe

Bandolero

I know what you mean by lifting off as it's about to shift. It is smoother.
HOWEVER, smooth means gentle slip into the next gear and slip means wear!!  :(
A harsh change means less wear on the clutches and bands in the auto, but it is hard on your neck.  ;D
Russell Bond - (Adelaide, South Australia)
1978 450SEL 6.9 .... #5166 .... 12/78 (Sold.) [url="//www.ezycoat.com.au"]www.ezycoat.com.au[/url]

1980sdga

Quote from: jbrasile on 29 September 2011, 01:17 AM
Ilike300SD,

I got used to doing that on my 79 300SD. With a diesel you are actually controlling the amount of fuel injected in the engine with the gas pedal, you get more control than with a gasoline powerplant where your foot opens and closes the air, not the fuel. Also with a turbo diesel if you feather the throttle and let the engine build some boost you get more power going up hill for example than if you just floor it. It is an interesting technique that gets better with practice.

Yes, shifting does get smoother but if the transmission is slipping you have to know when to ease off the pedal to make it shift more positive.


Tks,

Joe

Makes perfect sense!  I'll have to try that.

Congrats on the 240 Ilike300sd!  You'll have to post some pictures!

Casey

I'm half-tempted to put a 240D OM616 engine into a W116 SEL chassis, along with an extra gas tank in the trunk, just to see how crappy of performance I can get (fuel economy would be brilliant, though!).  My first two Mercedes' were 240D's and I miss the 40+mpg's...

Plus then these forum folks tired of hearing OM617 stuff wouldn't bother me anymore.  8)

jbrasile

Well Casey.... if you are into making a nice "Frankestein".... why not drop the 300SD drivetrain into the 450SE?

Just a thought...

Tks,

Joe

Casey

Quote from: jbrasile on 29 September 2011, 05:55 PM
Well Casey.... if you are into making a nice "Frankestein".... why not drop the 300SD drivetrain into the 450SE?

Because the 450SE is quite nice as it is.  If I was seriously going to go down that road which would take a lot of work, I'd want an SEL body.  In all seriousness though, I'd almost certainly use an OM617 turbo to pull that. :)  Because I'd want to be able to tow something as well.  Can you imagine an OM616 non-turbo in an SEL body with a trailer in tow??

Going up the rocky mountains in my 240D, I maxed out at about 30-35mph - I was flooring the pedal and semi trucks were passing me.  Shortly before that, I'd burned a hole through my resonator as the exhaust had come loose, so I was barreling out black smoke like I was running on coal.

If money were not a limiting factor, I'd make a 420SDL by putting the engine from a euro S420 CDI into a W116 SEL chassis.  That would be significantly faster than a 6.9, *and* easier on the fuel. :)  0-62mph in 6.6 seconds, max speed is 155mph (electronically governed, which could surely be removed, and in the W116 there would be about 500 pounds less dry weight).

Big_Richard

Quote from: Raptelan on 29 September 2011, 01:38 PM
I'm half-tempted to put a 240D OM616 engine into a W116 SEL chassis, along with an extra gas tank in the trunk, just to see how crappy of performance I can get (fuel economy would be brilliant, though!).  My first two Mercedes' were 240D's and I miss the 40+mpg's...

Plus then these forum folks tired of hearing OM617 stuff wouldn't bother me anymore.  8)

You may as well just remove the engine and install bicycle foot pedals and a chain in the drivers footwell attatched to the transmission ;)

Oh hang on, that wouldnt be any different to a 300SD in terms of performance anyway  8)  8)

Nutz

Scraping splattered snail shells off my back window would get rather dull after a while.

Casey

Yes, a 4-cylinder non-turbo diesel in a W116 would be slow as hell, and a bit insane.  But frankly, if you think a stock 300SD is slow, you're dead wrong and have never driven a turbodiesel.  I'm driving the 450SE every day now and it's not really much faster.  Has a higher top speed but realistically I don't need to exceed 100+ mph very often, and acceleration really isn't that much better to justify the gas expense.

This is what I really want (OM629):


0-62 in 6.6 seconds, top speed of 155mph, and a cool 25mpg. :)

There's also a S450 CDI now, but it seems the engine is identical to the S420 CDI, or wikipedia lies.

Ilike300sd

I agree.  I've driven every car under the sun -from old muscle cars to V12 V8 german cars to modern DI turbos- and no way is the 300SD slow.  When merging you don't feel traffic pressing on your back and you can cruise at any speed you want.  Also it has adequate power for passing. 

Casey

Quote from: Ilike300sd on 30 September 2011, 11:08 AM
I agree.  I've driven every car under the sun -from old muscle cars to V12 V8 german cars to modern DI turbos- and no way is the 300SD slow.  When merging you don't feel traffic pressing on your back and you can cruise at any speed you want.  Also it has adequate power for passing.  I dunno about the 240D though as I haven't had a chance to even drive it much yet, but the 300SD does just fine in traffic.

The 240D (at least the W115 version) has HALF the horsepower.  It is a real turtle - short onramps are rather scary and take patience.  Passing is right out.