[T2] enhance engine build tips

[Mike]

Hi Chris,

I just went through this - apologies, missed the first post; perhaps you're
already dug in.

Mine is a Type IV, 2.0, FI, 7.4:1 CR, Webcam 372 w/ hydraulics, 94mm dished
jugs, rebuilt stock oil pump. I can't possibly express how great this
engine is now - granted, I was running a GEX with 3.5 cylinders that ran up
to 450F around town, so the bar was low... when I got it apart, I could
move the rods laterally about 1/8" each way, and was losing 4 out of 8
valve seats. However, my rebuilt pulls strong, cruises at 70, and stay
cool. I believe that your engine is similar to mine on the internals, but
folks will chime in if not. Hopefully some this info is helpful.

Your budget will dictate some of your options, of course. I rebuilt nearly
stock, as I wanted to have as few heating worries as possible being in FL,
and because I really couldn't afford some of the additional mods to run a
more powerful engine - for example, new big valve heads, and I can't get a
decent extractor aftermarket exhaust on my rig, as I have a heavy-duty
hitch welded to the frame that I enjoy using.

Instead, I made sure to replace the little things that (to me) mattered -
hardware, cam gear, threaded oil galley plugs, rod bearings done properly,
mic'd and polished crank, balanced the pistons and rods, etc., etc. Every
component matters, as far as I'm concerned, so I wanted to do the best I
could within the budget I had.

 1) Most folks aim for Hoffman if they can afford new (via their site <
http://www.hamincgroup.com/main.php> or Raby's Type IV Store) or Adrian at
Headflow Masters <http://www.headflowmasters.com/> for rebuilds. I went
with Adrian - I was somewhat concerned when I got the heads back, as the
intake valves were taller than the exhaust. He offered to fix this, but
claimed it would not be an issue where I was running hydraulic lifters.
I've seen no issues at about 3K miles. I stayed with standard valve
sizes (37.5mm
intake and 33mm exhaust IIRC). I know folks in town running Type1 AVP heads
off the shelf that haven't seen issues, but I don't read great things about
them on the usual forums, so I avoided them.

2) There's tons of options - the question is whether, after you make an
engine capable of many more ponies, if it can shed the heat it needs to in
order to  survive. Lots of spots to read up on mods. I went conservative,
and my engine is better than my expectations. I used a Web Cam 372 (
http://www.webcamshafts.com/>. I've read the next cam up from the Webcam
142/342, the 73, works great with a slight increase in valve size works
well, thought folks report a loping idle. Raby offers some cams that
require a bit more mods to get tuned, but the reports claim it's worth it.
Anyway - there's plenty to read on this on The Samba and Itinerant
Aircooled.* *Stick with the OEM 94mm lower CR pistons so you can keep the
CR below 8:1 while retaining a deck height between .040 and .060.**

3) I had my pump (well, I sent two) rebuilt to stock spec by Phil
Eslin(?)(aka whip681 on Samba). About $100. My oil pressure is great. I had
clearance issues with the aftermarket cam gear than required some
Dremel'ing. I gave serious thought to using a Type1 pump, but concerns of
the case fit steered me away, and Phil came well recommended. I have an
external cooler I was going to plug on, but with my oil temps running
nicely, I'll wait until I have a feel for how it runs next summer with
people and camping gear. By and large, if the engine is tight, clean and
tuned, it should manage well.

4) I have an oil temp sensor in the taco plate, a Dakota Digital CHT on #3
sparkplug, and a split for the oil pressure sender so I can have both the
gauge and idiot light working.  It seems like there are pros and cons for
the location of both types of temp gauges. I'm of the mind that I'm more
interested in trends than down-to-digits accuracy - within reason. There
are threads around on different locations - I think on the T4 case you can
put one near the oil cooler, but I'm not certain. Search the forums.

5) Can't help here, but you might fish around for machine shops instead - I
lucked out and found one with a machinist who used to do VWs, but any shop
should be able to balance. I did what I could on my own with a couple of
borrowed scales from work.

6) I think you're thinking of the Permatex 3H form-a-gasket -
http://www.permatex.com/products-2/product-categories/gasketing/gasket-sealants/permatex--aviation-form-a-gasket--no--3-sealant-liquid-detail.
I used a variety for assembly, based upon recommendations I'd read.

7) Get the Wilson book, get your Bentley, get a dial indicator, double
check everything (even specs on new parts), and (especially important for
me) keep calm. I've built a couple engines (GM, AMC), but felt really
intimidated by the split case and measuring deck height, calculating CR.
The forum here is very helpful (a shout out to John Anderson who responded
often), and usually you get quick answers from folks who are really
experienced/ knowledgeable. The Samba also, but you can run into
conflicting opinions. I made a list of the options/ components I was
considering, the pros and cons, and cost, and came up with a couple
different configurations, then went with what I thought would be the best
bet, for me. Some thought might be given to what else you can do with the
engine out; shifter rod bearings, tranny leak fixes, accessory wire routing
were on my list.

I have a document with a ton of links on parts etc. I can send if it's
helpful. I also have a bunch of cylinder shims - so when you get to the
point of figuring your CR, give me a holler and you're welcome to ones I
have if you can use them. I don't intend to build another aircooled -
hopefully this one will last as long as I own the vehicle.  Mike

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> Here are some of those questions (non exhaustive list)
> 1) What is the best head out there
> 2) Parts to upgrade for more power.
> 3) Engine enhancement strategy , better oil cooling system, ....
> 4) Incorporate a temp sensor (at a different location than the sparking
> plug)
> 5) Where I can find a mechanic to balance the engine in California (bay
> area)
> 6) I remember someone mention ( a long time ago) a sealant which was use
> to seal airplane Aluminum Engine , does anyone remind me what it was ?
> 7) Any any tips to enhance the rebuild engine would be welcome.
>
>