[Vwdiesel] Rabbit droppings # 53 -- ( understanding the worth of HILLBILLY tuning )

H.Hagar h_hagar at prcn.org
Mon Mar 22 12:49:51 EST 2004

Lets take a look back at the days of plenty and HIGH octane gasoline.

Engine makers usa    increased compression ratios like mad ---- to outsell
the competition with more horsie power. What does that have to do with tuning ?
Quite a lot.    To use lower octane fuel we used HILLBILLY tuning. We kept
slowly retarding spark to a no-knock setting.

Likewise diesel ,  we have to keep advancing pump to correct for crappy low
cetane fuel. To do that with a dial-gage you would have to get the numbers for
40 cetane fuel from BOSCH.  Even then I would not do it , except as an experiment.

One of the things we are compensating for is Ignition Lag.Even the brand new
1984 Rabbit would need a correction. So what to do ???  Under dieselfuel 101 .
I suggested that we increase cetane number , using a cheap chemical.
Using the following reasoning. No way to test cetane number of stuff from pump.
So we say it is fourthy   then add chemical to get to 45 or 50.--- So what if pump
stuff is 50 ? --no problemo you drive on 60 fuel. NO way will it be too high.
Lets use the same chemical as is used by ESSO ExxonBobil. etc.

The higher the cetane the lower the lag.

May be continued.


PS:   Loren suggested we make a group purchase  .Great idea. Count me in.

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