Date:         Thu, 8 Apr 2004 22:03:44 +1200
Reply-To:     Andrew Grebneff <andrew.grebneff@STONEBOW.OTAGO.AC.NZ>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Andrew Grebneff <andrew.grebneff@STONEBOW.OTAGO.AC.NZ>
Subject:      Re: State of the Art in Engine Swaps is....long
In-Reply-To:  <57DAA45518967B49931D2122BA96E6A78A7239@hsnc-mail.hazenandsawyer.com>
Content-type: text/plain; format=flowed; charset=us-ascii

>Eric Zeno wrote:
><<<
>I have 2 extra inline 4Cly. you can have. Both are 1.8L golf engines.
>>>>
>
>Color me seriously ignorant as I came up in the "there is no replacement
>for displacement" years. How does one gain an advantage by replacing my
>1.9L or 2.0L with a 1.8L?
>
>David Higginbotham
>82 Westfalia
>Silk Hope, NC

It is more correct to say "there is no substitute for
sophistication". A more modern engine, with DOHC, 4 valves (or more,
as in the Corolla engines), multipoint injection etc will usually put
out considerably more power than larger cruder old engines. And more
reliably (wink wink).

Funny though, the old late-60s-to-70s Toyota 18R-G 2.0 put out
140+hp. It was DOHC but only 2 valves per cylinder, and carburetted.
So there are exceptions.

The old US adage was perhaps more relevant when few engines were even
SOHC. Of course an engine of a given design will tend to develop more
power in larger capacities, up to a point... cylinders over 250cm3
tend to have problems filling and exhausting, so become less
efficient beyond that point. Huge cylinders cannot develop good
specific power (kW/volume) because of this, and need supercharging to
overcome it.

>This question has multiple answers. The displacement isn't the only factor
>that determines hp.
>
>If you go to Fast Forward's engine conversion page you will find engine code
>charts.
>
>These enable you to determine your hp, torque etc.
>
>Some 1.8 engines are rated at 85 hp, for example, while others are rated at
>105.
>
>The cam, rods timing all control the final hp and torque output.

Valve size, number & angle, combustion-chamber volume & shape etc are
just as important. So are inlet tract & exhaust diameter, shape,
length and degree of backpressure. As well as the safe rev band.

>So though your 2.1 WBX may be rated at 95 hp,
>my 2.0 Golf motor (ABA code rated at 115 hp. ) has more because of the FI
>system, valves, rods and belt -driven camshaft, as opposed to pushrods.

Jeez, my mother's 75 Scirocco TS had 112hp, and it was a single-carb 1.5.

>Throwing my .02 into this, having owned and driven a number of VW/Audi I-4
>powered vehicles both in this country and in Europe, 4500 rpms for an
>extended period of time seems to be fine.  In fact, maybe it is just my
>right foot but on long trips in my '87 Jetta (9A trans) I would often find
>myself creeping up to 80 mph which was a little over 4k on the tach.  Yes,
>the VW/Audi I-4 is not the smoothest or quietest at those engine speeds, but
>I don't think that was the issue.

I put an Audi Fox injected (K-Jetronic") 1.6 into my 74 Passat S 1.3
fastback. I guess it was about the same power as the Scirocco TS. It
was content to sit on 160kmh (100mph) for extended periods.

>I can't imagine why
>the engineers would have designed these engines to run very fast for long
>periods when they never have to do so in the vehicles they are designed
>for?  My guess is that these newer engines are just so darn
>bulletproof that they can take the beating though.

Ever hear of autobahnen? These cars are designed for this. Some
engines are also designed in such a way that they will happilt rev
far faster than the tacho redline. Honda's old CB450 of the 60s-70s
springs to mind. redlined somewhere about 10000rpm, they would
happily spin to well over 15000.

>The inline 4 cly. VW engine have a red line of IIRC 6500 RPM's
>where as most other 4 cly. of its time, red line at 5000 RPM's

My DIESEL Toyotas reline at 5000.

>  I-4's also
>have a higher redline so you can get better top end. The little guy
>can keep reving while you 1.9 peters out at about 4200 rpm. (puns
>intended)

So anyone know what rpm an engine would be turning at 80mph when
attached to a 57 van's stock trans? My old single-port 1600, in this
panelvan, would readily do 80mph (premetric speedo).


--
Andrew Grebneff
Dunedin
New Zealand
<andrew.grebneff@stonebow.otago.ac.nz>
Seashell, Macintosh, VW/Toyota van nut