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Re: [T3] Type engine longevity


<x-charset iso-8859-1>Hello-

> In the size you're talking about you can make a virtually bulletproof 
engine 
> built up on your stock case. This is a lot easier and a LOT cheaper.

Aye, true.

The T3 vs. T4 idea depends on what you want to do with it.  Most 
people, when asked the question "what is your application?" usually 
don't answer completely enough.

A T4 WILL take much more use and abuse.  Trust me... I dish out plenty 
of it when I'm driving.  For my style of driving, I wouldn't be caught 
dead with a T3 and a T3 engine unless I was going for a vintage 
restoration.

If you drive the car conservatively and remember that you really only 
have a ~30-35hp engine (yes, more peak power, but more than a 30-35hp 
duty on a stockish T3 engine will radically decrease life expectancy), 
you can make it last a very long time.  But, if you want to keep up 
with the rest of traffic up that 6% grade, or you want to keep your 
foot in it for longer periods of time, then the jump to an engine that 
can structurally withstand more force, thermally withstand a higher 
heat load, and dish out a lil more power to boot, then you will very 
quickly see the benefits of a T4 engine.

 
> > (1)New AS41 Universal Case
> 
> I thought the HP case was the AS21. 

AS21 and AS41 are two alloys of magnesium, and are not VW code 
words.  "Magnesium AS21" is like saying "Stainless steel 304" 
or "aluminum 356" - it's just an alloy number!  If you have the right 
resources available, you can see why VW chose each one...

AS41 has a higher yield strength and higher corrosion resistance.

AS21 handles fatigue better, especially at higher temperatures.

So, the main bearing saddles will pound out less easily with AS21, but 
AS41 is harder to crack and won't turn white as well.


> > (2)Welded .10/.10 counterweighted crank 
> 
> get counterweights added to your std/std crank. Berg will do this, 
but it 
> takes time.

IMHO, once you put a welder to a crank, you really should regrind the 
journals.  I know that in theory if you spend enough time you can keep 
it std/std and avoid warping, but in practice I'd have it reground.  It 
doesn't hurt anything to be a little under, so long as you can find 
good bearings.

The only time I don't like to do this is when the bearing supply is 
crapper.  For example, on the 3rd or 4th align bore, which is 0.060" or 
0.080" over, you can't get a steel-backed center main bearing.  I'm not 
such a huge fan of that :-).

 
> > (3)WebCam "86" Grind with matching Johnson lifters.

*Maybe* a bit big for an otherwise essentially stock engine.

> > (4)Rimco Rebuilt Connecting Rods
> 
> I get mine done by RIMCO because they do it for cheap and the quality 
> seems just fine. You should follow up by letting Berg balance them 
with the 
> rest of the moving engine parts.

Yes indeed - dynamically balance everything!  It's cash worth spending!

> > (6)Schradek blueprinted oil pump
> 
> I don't know this one, is it better than Berg's?

I think he means "Schadek."  They're a Brazilian company that makes 
aluminum-bodied oil pumps.

I know I'm against the norm on this one, but I like iron-bodied pumps.  
The argument for aluminum-bodied pumps is that the pump body and case 
expand the same way.  But, no matter how you cut it, the gears are 
still steel.  So, with a pump body that expands more than the gears, 
the clearances inside the pump open up with temperature and oil 
pressure goes down...

I get iron-bodied pumps, then very carefully blueprint the backlash of 
the gears to just a *hair* above zero (not difficult to do... lemme 
know if interested and I'll detail it here).  To seal the pump body to 
the case, I use Loctite 518 on the stock paper gasket AND I use some of 
the stuff around the pump inlet and outlet so it doesn't leak back into 
the sump.  To seal the cover to the body, I use NO gasket (which makes 
the backlash setting beautiful!) and just a little bit of Loctite 518 
sealant.

I've found this is the best way for a leak-proof pump, and yields 
EXCELLENT oil pressure.


> > (9)OEM VW heads with 3 angle valve job, port match,
> > mild port and polish, 40mm by 35.5mm valves, with solid
> > rocker shafts on OEM rockers

Who's doing the work?  That can make a HUGE difference in quality vs. 
crap...

> 
> Add swivel-foot adjusters.

Only if Genuine Porsche 911... the aftermarket "copies" are known to 
break.

Although difficult to find, if you can find some genuine 8mm Type 4 
adjusting screws, they're quite nice.  They have a large head, so you 
cannot remove the adjuster from the rocker arm without removing the 
rocker arms from the head and unscrewing it the opposite direction.  
Very slick.

Take care,
Shad Laws
LN Engineering
http://www.LNengineering.com

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