"Alfistagj" > wrote in message news:<jEWHc.1631$vH5.767@amstwist00>...
> "NC" > schreef in bericht
> ...
> > All,
> > I am fairly new to the Alfa world - bought my first used 156 1.8 petrol
> > (t reg - 1999) about 3 weeks ago.
> > A strange thing I have noticed however, is the uneven acceleration I get
> > in 2nd. If I move off, up into 2nd and then floor it (or even just get a
> > little enthusiastic with the throttle), the car picks up slowly until it
> > hits about 3000 rpm and then takes off ! Is this slight delay in power
> > normal, or should I be looking for a problem that would cause it ??
>
> Moving up from 1st into 2nd and having the enigine fall beck under 3000rpm
> mean that you change gear too quickly.
> Try shifting gears at 4500/5000rpm, then you fall back in rev's above
> 3000rpm
> Most Alfa engines are a bit "lazy" under 3000-35000 rpm or better, the
> (extra)power comes at 3500rpm and over letting you believe it's lazy under
> that rpm's.
> When you measure acceleration over the rev band, you will see that that's
> hardly the case.
>
> By specialist chip tuning (not the job done by people advertizing themselves
> as "tuners" and trying to let you believe they can do miracles for 300-400
> euro's!!!) they can change the power band / torque range quite radically and
> change a 4 cil TS engine into a 1.9JTD / V6 "look-a-like" in respect to
> power in the mid rev range.
> The feeling of lack of power under 3000rpm can be taken away completely
> giving you a very smooth feeling of having ample power available all over
> the rev band.
> I have my 2000 156 SW 1.8 tuned this way; it has become an absolute "killer"
> on available / useable torque. I certainly beat "standard" 2.5V6's (not on
> top speed) and the older 1.9JTD's
> The newest 1.9JTD is another story let alone the 2.4JTD and the GTA; that's
> are other leagues!!
>
> This is quite different from more top power (HP's) which can only be
> increased very lightly on a non-turbo engine (10-15HP is the absolute max
> when "only" doing a chip tuning job; don't belive the "miralce stories"!!!)

an absolute "killer"

Let's not get too carried away here!

1.8 engine has 120lb/ft @ 6500 and 140hp @ 3900. The SW being 1315kg

2.5 engine has 163lb/ft @ 5000 and 190hp @ 6300. The V6 being 1320kg

A chip would need to raise torque on a 1.8 by 30% at least to get
anywhere close to a 2.5, but still wouldn't have the HP to move it
fast enough. Maybe in a turbo car but no chance in N/A.

I think you've been racing old men or broken 2.5s ;-)

Simon
2.5 V6 - a proper one.