Date: Wed, 5 Jun 1996 10:53:31 +1200
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: william.warburton/OU=tritec@dsw.govt.nz
Subject: Re: G60 in a Vanagon
Hi Volks,
Ric writes:
> There is a major issue in putting "high performance" VW watercooled engines
> in Vanagons, etc....and that is the rpms and torque production.
>
> For example, the 5 cyl gas engine in the Eurovan is an Audi unit, which in
> the Audi 5000 puts out something like 125 hp....the EV unit is "detuned" to
> 105 hp...but its torque band kicks in at about 2000 rpm and stays pretty
> flat....
So, how is this acheived? How do you tune an engine for low
end torque instead of High end HP?
As far as engine substitution in buses is concerned I assume that a
good choice of engine (for low end torque) would be one with plenty
of displacement, designed to produce power without needing to spin too
fast, and without fancy engineering to increase output at high speeds
(16V heads, peaky cams,blowers etc).
The usual performance boosting tricks for cars seem to make an engine
less suitable for bus use, though presumably an appropriate engine would
benefit from decent breathing and big carbs without losing any bottom end.
But then an "appropriate" engine wouldn't necessarily suffer from other
enhancements- the potential problem is in choosing an inappropriate engine
which seems powerful because of high revving HP figures in the first place...
So the lesson is: Forget the fancy stuff- for good torque chose a simple
(but large) engine. Then there's no point "developing: it because you can't
sensibly use the top end in a bus anyway.
Right?
W.
PS: There's a garage here in Wellington that has a late 70s bus with a
V8 in it.
The "conversion" is ugly- radiator is mounted on bull bars (like a
front mounted
spare wheel) and there is no engine lid as the engine is too big to
fit. The owner
say it will cruise "at tickover" (obviously exaggerating, but..) at
140km/h (90mph)
and that the biggest problem is people pulling out in front of it,
thinking it's doing
80 k's!
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