Results of sonic block test 2.0TD

[rabbid79]

Hi Guys,
I had my 5-cyl. block sonic tested today.  I wasn't able to get as many measurements as I wanted, but I got enough to tell the story.  Here are the overall findings on a block with 110K miles, and an original 76.5mm bore:
Top-most centimeter of each cylinder was too thick for the tool to measure, but looking at it through the coolant passages, it's around .400".
Down 1.5" into the bore on the thrust faces was #1-0.284"   #2-0.288"   #3-0.298"   #4-0.275"   #5-0.280"
Halfway down the bore on thrust face of #4-0.208"
Up 1" from bottom of bore on thrust face of #4-0.288"
Bottom of bores too thick for tool to measure.
I only got two side wall measurements, and at half-way down the bore they were #1-0.271" and #5-0.257"

I would like to go to 80mm pistons, which would remove 0.069" of meat from each wall.  This would take my lowest measurement of 0.208" down to 0.139".  There are a lot of varying opinions on what the minimum cylinder wall thickness should be.  0.139" seems to be a bit on the low end, especially considering that I want to build a highly boosted engine.  I think I'll pass on the huge over-bore.  It looks like perhaps a 92.8mm crank may be in my future instead.  I'll head out to the garage and take a few measurements.

[Turbinepowered]

You want to go with a 3.5mm overbore from stock? That's a big overbore! 

[rabbid79]

Ya, but that 0.208" number kind of killed my plans.  Who knows how many other "thin" spots there might be that I didn't find.  That's ok though, it was $20 well spent.  It's good to know that overall, the cylinders are very stout, and should take plenty of abuse.  It's too bad there's not some middle ground piston like 78.5mm that's available.

[jwspin]

off topic but man you have a nice fleet of cars......

[arb]

Yeah, I would not go 0.069" over - that's risking a cracked bore at some point in the near future. I did go 0.120" over on a Chevy I re-maned, but that was a 283 and that brought it to the wall thickness of a stock 327 so there was no risk.

[Turbinepowered]

Don't suppose there is a chance of resleeving to thicker cylinder liners to let you bore it out that much?

[rabbid79]

Hi guys, thanks for your replies.  I went out and took some crude measurements to see if stroking was an option.  Obviously, it would require a 92.8mm stroker crank ($800) and custom rods ($900), and would leave me with a horrible rod ratio.  The ratio would be worse than any production engine I know of.  Things are just too tight inside that block to even try.  If I already had the crank that would be one thing, but $1700 plus a bunch of headaches just isn't worth the roughly 10% increase in displacement.  This is all good though.  I know that boring and stroking isn't really an option, and can now focus my energy on building an all-out 2.0.

[Rabbit on Roids]

keep me posted, im about to pick up an 82 Audi 5000 TD w/ that engine in it, the 2.0 turbo 5 cyl. and i want to make it fast.

[rabbid79]

I sure will.  I'm putting the engine in an '89 100 Quattro.  I plan on going all-out.  Just waiting for the stock market to turn around a little before I can really get started.  Are you planning on keeping the engine in the car?  I hope so.  I love type 43s.  What color is the interior?  Is it the checkerboard cloth?  I would liked to have kept the '83 that my engine came from, but it was in horrible condition.  I had to let it go.  By the way, I know they made TDs in '82, but I've never actually seen one.  All the ones I've seen have been '83s.  As far as I know, the '82s are pretty rare.

[Rabbit on Roids]

its white, and yea, i plan on keeping the engine in the car for a while atleast. it has blue interior, looks checker boarded. it looks like the car is in awesome shape for being on the coast in a rain forest.

http://seattle.craigslist.org/sno/cto/1256378494.html
if you buy it out from under me, i will find you 

[rabbid79]

Awesome.  My nice one from years ago had the same color interior, but had a charcoal grey exterior.  This white one looks to be in very good condition.  I hope it treats you well.  Make sure to pick up a Bentley.  If you keep your eyes open, they can be had for as little as $10 on eBay.

[Rabbit on Roids]

are bentlys really that good?
cause ive never had one, and ive always gotten by.
also, how hard is it gonna be to swap in a 5 spd manual?
how much harder would it be to swap in quattro? didnt these cars come with it? but not with a diesel of course.

[rabbid79]

Yes, the Bentley has tons of good information.  It shouldn't be hard at all to find a good tranny.  You should probably be looking for the FWD 016 or 01A types.  Check out the other thread you started regarding Quattro.  You should also check out motorgeek.com.  There's not too much there regarding diesels, but there is tons of other good information about trannys, axles, clutches, etc.  Go to car-part.com to find a good FWD tranny.  I just looked and saw dozens that would probably work for less than $250.  Since you're going to increase the power on yours, I'd look for a tranny with taller gearing.  I'm not sure which one that would be though.