Date:         Sun, 24 Sep 1995 22:11:05 -0700
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         eugp@uclink3.berkeley.edu (Eugene C. Palmer)
Subject:      Engine Reccommendations-type 2

Maniacs,

Looking through the archives from the week I missed while vacating I see
some people who would like to know what engine people reccommend for the
1971 bus.  Specifically terb@adobe.com and martino@earthlink.net.  OK, here
goes.  My assumption is that you want to drive from Mexico to Alaska and
want the car to get you there and back, at least.

Start by getting Gene Bergs catalog and reading it, even if you don't get
your stuff from them you should educate yourself to at least this level.
You should also find Bob Hoovers sermons and read them.  'How to Hot-Rod
Your VW' gets on the list too.
 
Do not start your engine with anything less than a NEW AS21 universal case,
period.  Unfortunately this all but eliminates your basic GEX/MOFOCO etc.
rebuild.  New cases hold their bearings tight, and correspondingly their oil
pressure, when hot, line-bored cases don't.  My AS21 case holds 20 psi at
idle even when overheated to 250 degrees, running straight 20W oil, and a
26mm oil pump.  This also eliminates problems getting the right case
mounting holes, oil dipstick, pressed in nut, etc.

69 mm counterweighted crank.  While this is not required, it will give your
new case more life.  A lightweight flywheel is usually paired with this to
offset the added rotating weight, though I've used the stock flywheel
without it making an incredible difference.  Bergs rap about crankshaft
machining is worthy, I believe part of the reason my oil pressure is so good
is because the bearing tolerances are ground to their minimum.  If you don't
get a Berg crank, then I would suggest that you get a NEW VW crank, they are
lighter weight than the original issue, and you know you have a crank that
is straight, balanced and machined with the minimum tolerances.

Take a close look at the main bearings, I've seen two kinds, the
unacceptable kind has a groove on the OUTSIDE of the bearing.  There should
only be an oil groove on the inside (crank surface) or more oil will leak
through the critical bearing/case surfaces.  While your looking at the
bearings, check the #1 thrust bearing fit, it should be nice and snug.  If
not, you'll end up with Gerry Skerbitzs problem of the end play being
trashed because the bearing is moving.  This can also be caused by someone
tighting the gland nut with too much shim in place, ruining the #1 thrust.

Double thrust cam bearings are required, copper faced too.

Use the stock cam, make sure it fits perfectly, .002 end play, 0 or.001
backlash.  The valve train tracking depends on it, as well as the gear life.
Any other cam will waste your heads prematurely.

I add a groove to the lifter as per Bergs reccommendations.  It allows the
use of high lift rockers later on, and quiets the valve train a bit.  Use
new lifters and break them, and the cam, in properly.  This means using STP
and/or light grease on the face of the lifters and the cam lobes when
assembling the engine.

Check the oil pump fit, either it has to be perfect (refer to Hoover sermon)
or you need to get Bergs modified pump that uses an O-ring on the front,
eliminating suction losses. You just have to be more careful installing it
so the O-ring doesn't get mangled.  26mm should be big enough unless your
going for hydraulics, or you're forced to re-use an old case, in which case
a 30mm pump is appropriate.  A 30mm pump will blow oil lines, filters, etc.
so be careful.  I've done this too many times to admit too, don't make the
same mistake.  Do not get a cast iron pump, it's expansion rate doesn't
match the case material surrounding it and will leak.

With the case empty, fit the distributor drive gear to the distributor and
make sure it doesn't have too much end play.  It's alot easier to do with
the case apart then losing shims into the case later.

Balance your rods to within 1/2 gram.  Do this yourself with a beam balance,
grinding off excess weight evenly from the rod cap.   Balancing the rods
makes a noticable difference in how smooth the engine runs, especially at
high rpm's.

Use red or green locktight on all the case studs, rod nuts, and case nuts.
Green is better, but harder to find.  I got mine from a bolt supplier for
alot cheaper than auto parts stores.  Use Permatex Aviation 3H or whatever
Bob Hoover reccommends to seal the case.  

OK, now for the fun part.  I think 1776 is the most appropriate size for a
strong bus.  It uses the stock size crank and rods, doesn't increase fuel
consumption too much, doesn't create too much additional heat if set-up
properly, and parts are available and not too much more expensive.  I paid
$175 for my last set, as compared to about $75-100 for stock.  This is the
90.5 cylinder and will be a forged piston which should last as long or
longer than the stock size cast pistons.  What is required to keep the heat
down is to drop the compression to _6.7:1_, unfortunately this means shims
under the cylinder (~.1" ) which widens the engine and complicates
exhaust/intake installation.  You will also need to have the case spigots
opened.  I would not reccommend the 1641cc slip-in kit as it has a thinner
cylinder wall and will scorch sooner, and I know at least one splittie owner
that has had them crack.  Pistons should be balanced from the factory, but
it can't hurt to check.  Also, don't assume that the rings are properly
oriented out of the box, pull the piston and reset the rings so you _know_
they are correct.  Use a light oil (20W ND) to assemble the pistons to the
cylinders.

Another fun part is what head to use.  I think that heavy duty single
springs live longer than the stock springs, and are required if your going
to be using a high lift rocker arm.  I do not, however, think that dual
springs are needed unless you're really into 5000+ rpm rev's.  They add wear
to the entire valve train, rob horsepower from the engine and require steel
pushrods.  Do not use any heavier spring if you're going to attempt
hydraulic lifters.  Use either Bergs semi-hemi cut head (54cc+), or the
'stepped' smog head that FI squarebacks use, they have a larger chamber
(52cc?) and will require less cylinder shimming to get the compression down.
You will need to have the heads opened if you're using the 90.5 cylinder
kit. I have a theory that the single port head runs cooler and lasts longer,
(less power) but I can't prove it.  I totally dig high lift rockers, either
1.25:1 or the more exotic 1.4:1.  Do it if you've cut the lifters and gotten
the heavier valve springs, don't if you haven't.  Take a close look at the
way the rockers contact the valves and make sure they are aligned correctly.
Don't use anything but the stock cam with these, or anything, I say.  Check
Bergs notes on this. 

The main thing is to measure things up and calculate your compression ratio
to 6.7:1, otherwise you'll be making a hot running engine.  Another reason
to keep CR down is so you can use regular (87 octane) fuel.  This becomes
very important when you're in nowheresville (read Alaska) and you don't have
a choice.  The VW manual for difficult conditions calls for this type of
engine set-up, except they use dished pistons.  I can't see why anybody
would use a rebuilt head, risking stripped spark plug holes, cheap cast iron
valve seats, guides, valves, etc., when new ones are available.  The
difference can't be more than a couple tanks of gas.  It is true that a
6.7:1 engine with the stock 34 pict-3 carb will have less power than a 7.3:1
(~stock CR) engine, but when dual or progressive carbs are added, that
difference disappears and you end up with more power and less heat.  Timing
needs to be advanced from the stock CR, the bigger the carb, the more timing
you can run.

Ah Ha, carbs.  Gee let's see, I've had 28 PICTs, 30 PICTs, 34 PICTs,
Dellorto 34 FRD's, Kadrons, Weber 40 IDF-XE's, Solex 32/34 PDSIT (which I
have yet to run, but will shortly), and the HALTECH F7 PEFI system.  For the
guy asking about FI systems I have this to say; consider the mechanic, and
consider what you will do when you're in West Stinkville Monholia,
population 6, elevation 16,700 meters, you can't figure out why your engine
is running on one cylinder, and your girlfriend is suddenly ill.  I really
had some good times with the Dellorto FRD 34 single throat dual carb.  They
were efficient, had great pick-up, and ran cool, even in a stock engine.
The throttle bushings wear quickly for some reason.  The Kadrons were pretty
good too.  At this point I refer to Bob Hoover and Gene Berg, both at the
same time!  They both have excellent, incredible really, background and
experience.  Also consider smog requirements and your obligation to your
fellow air-breathing humans.  Fuel injection systems MUST have an O2
feedback circuit in order to be at all reasonable (the HALTECH F7 doesn't).
Basically I think dual carbs suck because your have to go to hell and back
to change spark plugs, but I still love them.  Whatever you do MAKE SURE
THEY ARE GETTING LOTS OF FUEL!  Don't think you can put a big engine
together and then starve it for fuel to get economy.  It don't work that
way.  I ruined at least two engines putting fuel regulators on them, yuk.
BIG fuel lines, strong fuel pump (check it), lots of fuel, no restrictions,
period.  

I like electronic ignitions and have a Stinger S4.  It's great, and
expensive too.  Whatever dudes, go for it, and keep a backup 009 in your
parts kit so if it dies you can still get home.

Right now my 1971 bus has the 1776 engine with a CW crank, LW fly,
non-doghouse air system without thermostat, stock intake (34 PICT-3), stock
distributor, stock heads at 6.8:1 CR, and the cheapest extracter exhaust
money can buy.  It was timed at 5 ATDC for the smog check, but is now at ~7
BTDC so it will run right.  It runs too hot on the big hills (230+, which I
attribute to the carb and distributor), uses regular gas (87 oct), gets
about 18-20 mpg, and is too weak for me.  I'd like to get the Solex PDSIT's
and Stinger on there, but will likely leave it until I can get the 2 liter
thermostated FI engine back in there.

Whatever y'all do, fix your brakes and suspension first.  At least perfect
stock brakes, gas shocks, radial tires, 5/8" anti-sway bars, perfect
drag-links, tie-rods, king pins.  Fix the #$%^&*() parking brake cables too.

Read Bob Hoovers sermons, read Gene Bergs catalog, nuff said.

Well I've been poking at this post for at least a week now and it's time to
put up or give up.  Here you go.

Eug,
'71