Hydraulic Tappet speed limits

[Mark(The Miser)UK]

1800 RPM torque peak?  Sounds like you are confusing the power curve of a TDI.

The power curve plot of a stock 1.6lTD, as provided in the VW TD SAE Paper #830441, shows that torque peaks at 2600RPM (or, based on my testing, when boost pressure initially reaches maximum):

The stock power curve is also not flat; it is upwardsly-increasing.

?

If this diagram is of a typical standard issue vehicle; then what has determined this torque peak?
 Is it limited by the max fuel screw?
Or is it due as you're referring to the limited boost pressure and so altering waste gate should result in a rise in torque after a rise in boost?
Or is it because most boost is linked to an increase in fuel too?

What I am trying to solve is:
I have two 'Quantae' Unaltered in any way until I 'fiddled' with them...B4 I did I stuck a boost gauge on them both.:
My regular vehicle produces about 9psi and the other produces 11psi or so.
 I've not driven the latter much; but it doesn't seem any more responsive... :?:

[VWRacer]

Mark, yes I think that the fuel screw is what determines max torque (and power). Fiddling with the governor should permit revving to higher RPMs, and in conjunction with the fuel screw may well affect where and how much power and torque the engines can make.

[vwmike]

1800 RPM torque peak?  Sounds like you are confusing the power curve of a TDI.

The power curve plot of a stock 1.6lTD, as provided in the VW TD SAE Paper #830441, shows that torque peaks at 2600RPM (or, based on my testing, when boost pressure initially reaches maximum):

The stock power curve is also not flat; it is upwardsly-increasing.

I also agree that if you are just puttering around town and only drive a diesel because you are cheap, highly concerned about engine wear, or only drive a diesel for the fuel economy, it makes sense to keep loads high and therefore to short-shift and not wind the engine up.  But if that is true, then why are you wasting your time in the "IDI Engine performance" section of GTD Forum?

According to volkswagen.org (now not working, but I saved the important stuff off of webarchive.org) the figures for the TD were 68hp@4500 and 98ft/lbs@1800. I drive a diesel because I'm in college and fuel is expensive. I have a gas rabbit that gets sub 20 mpg, so I enjoy fuel economy when I can. It's also just something different for me to screw with. I probably will buy a tdi...possibly even within the year. But, for now I have IDI's so that is what I'm working with.

[Mark(The Miser)UK]

I also agree that if you are just puttering around town and only drive a diesel because you are cheap, highly concerned about engine wear, or only drive a diesel for the fuel economy, it makes sense to keep loads high and therefore to short-shift and not wind the engine up.  But if that is true, then why are you wasting your time in the "IDI Engine performance" section of GTD Forum?

That's a bit harsh :shock:
 :mrgreen: If you want to look at the picture look at the cover... BUT if you want to know how it works then do the jigsaw :mrgreen:
[RANT-ON]
 :idea: One of the reasons I came to this site is because this is where the 'knowledge' is... Whilst I don't wish to race my vehicle to the point of destruction; I want adequate power in reserve for that occasion that requires it. Rumour has it that increased power and  greater economy can be had at the same time.
The true power of a forum is the melding of minds to produce consensus  (or otherwise). It can also learn from those on a budget and those with deep pockets.
One final thought; whilst the Bentley is a cut above the Haynes, it is still wrong on some things:
 I must have hundreds of cookery books; but only a few  recipes have any chance of producing 'shop made' results. That's where a forum like this can reveal those secrets that Bosch doesn't want you to know...
[RANT-OFF] :idea:

[farkman]

Damn, I didn't even notice that. Thanks.