fuel to the fire: 16v's are BAD!

[btpeet at effervescent.com (Bradley Peet)]

Hi, Dan!  I'm perfectly calm, believe it or not.  Honest.  O:)  See my halo?

I guess I should have added a few :P's and ;)'s in there but I forgot that
sometimes people take things on the Internet the wrong way or otherwise too
seriously.  I guess I got a couple digs in there, but it was nothing
personal.  Heck, I don't you know from "Adam".

Now back to the topic at hand.

Quite a few things have happened since 1988 and it's safe to say many
attitudes and popular beliefs have changed as well.  Post-1988 the 2 liter
16V (9A) motor was released, the traditional 8V motor went by the wayside in
favor of the crossflow, and VW now cranks out 1.8T motor like popcorn.  More
importantly than the timeframe is the source.  This Robert Collins guy is
obviously expressing some very strong and EXTREMELY biased opinions, in
addition to alleged HP number of various Drake, Oettinger, and VW engines in
their stock form.  The Drake numbers were very impressive for the day but a
stock 16V head will still outflow all but the best worked 8V heads out
there.

Collins says "DON'T (read that again DON'T) get a VW 16v.  They are
absolutely junk.  If you saw the insides of one, you would puke."  Strange,
I've seen the insides of one and it didn't cause me indigestion.  Likewise,
I know of stock 16V bottom ends that are putting down 300 at the wheels and
holding up just fine.

Collins says "It is a dead-player for high performance."  Not sure what
Robert was smoking back in '88.  Some normally aspirated 16Vs are making 200
HP with fairly mild cams, like Bill Brockbank's 2 liter 16V Jetta with
throttle bodies and DTA fuel injection.

Collins says "The exhaust valves are top-dead-center over the combustion
chamber, and make a 95 degree bend around to exit the head.  BAD!"
Top-dead-center?  Bad analysis, Mr. Collins!  BAD!  The 16V exhaust valves
are indeed perpendicular to the cylinder bore but, on the 8V head, both
intake and exhaust are 90 degrees (perpendicular) to the cylinder.  Flow
bench tests are unambiguous about how much more 16Vs can flow than 8Vs and
everyone knows it.

Collins says "Furthermore, suppose you buy the motor, you would need the
fuel and spark managemnt systems."  Pretty easily had through junkyard or
Internet channels.  Fact of the matter is, you need to tweak the fuel and
ignition on any motor if you want optimal power.

Collins says "Your '83 GTI has 8.5:1 compression ratio.  That is barely
managable for a turbo.  A turbo likes about 7.5:1 c/r."  Wha?  Huh?  OK,
maybe 15 years ago that was the conventional wisdom for people who still
refused to embrace digital fuel injection and ignition systems.  8.5 CR is
GREAT for a turbo motor!  7.5 CR is absurdly low.  Factory 1.8T motors run
CR in the neighborhood of 9.3 to 9.5.  When VW/Audi decided to crank the
boost up on the 225 HP Audi TT and the 380 HP RS4 biturbo, they lowered the
CR to 9.0 to 1.

As you can see, almost everything this guy Robert Collins said is either
severely dated or questionable altogether.  It would be awfully silly for me
to call him up and offer my unsoliticed opinion.

You wrote:

> You say "Sure you can get decent gains with a big valve head, cam, and
exhaust,
> but where do you go from there?" and my answer would be the same place as
any
> other motor. The $ per hp curve you mention gets steep quickly with any
motor
> with any amount of valves. Your point?

I'd say you're pretty much DONE with you 8V at that point, outside of
increasing displacement or replacing the CIS with programmable EFI or carbs,
all of which are increasingly more expensive options.  I'm going to assume
by that point you've already had the head ported and polished.  All you
could really do is go to a more radical cam and destory your low end torque
or spend a lot of money on a stroker kit and new pistons.  So, my point?  As
I suggested before, with the 16V you'll spend more up front, but you'll be
significantly ahead of the 8V and still have room to grow.  I've seen a 2
liter 16V still running CIS-E and Shrick 276 cams and lay down 154 at the
wheels (about 170 at the crank), and it was running a bit lean!  Up to about
130 or 140 HP, 8Vs offer more HP per dollar but my point is that many of us
aren't satisfied with only 140 at the crank.  Now consider that a stock 2
liter 16V makes 134 HP at the crank, and over 140 with a $200 euro intake
cam.  Only a 16V has the potential for 170 to 200 at the crank in a
configuration still suitable for daily driving.

Again, the bottom line is that used 16V motors today are relatively
inexpensive and will produce more power than most tricked out 8V motors plus
give you room for even more power, as your pocketbook (and wife?) allows.
It is also worth mentioning that the whole 8V vs. 16V argument is silly for
a whole variety or reasons, but mainly (and objectively speaking) because if
you really want to go fast in a Scirocco you are pretty much going to NEED a
turbo.

Have a nice day. :)

Bradley

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