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[friskynibbles]

alright - got most of the engine apart and ordered a pile of stuff from weissach (hopefully everything i need).
so far i have the head off and cleaned and the valves out. i've got the stuff to do a port and polish and a valve grind. got the oil pan off and the pistons out. can't seem to get the crank out tho.
so far the problems we have found with the engine are a blown headgasket and a missing piston ring (the spring is still there) on piston one - the piston that hadn't been firing. there is still coolant everywhere from the blown headgasket but remarkably no serious problems yet.
cross yer fingers and send advice!!! reply to this if you have anything at all to suggest etc.

[Richard]

Are you going to do a rebore or reuse the pistons? If using original, very important to get good measurements of piston clearance to cylinder and out of round of cylinder. Also ring fit in piston lands. The health of your new engine depends on this, as does power and oil consumption. Chrome rings or iron rings? Each requires a different surface hone finish for proper seating.

If it is in the budget, get crank and flywheel balanced as a unit. Also get rods within a few grams of each other.

Why don't you tell us what you are planning cause I don't want to guess or insult you if this is already basic info for you. By the way, Tweeks has gapless piston rings that look really neat.

Do you know what a three angle valve grind is? You need to do this on head.

[ This Message was edited by: Richard on 2002-06-29 13:51 ]

[friskynibbles]

ok so I plan to port and polish myself, do a quicky valve grind thingy myself. i plan to have a shop plane the head and maybe the block, hone the cylinders. the flywheel also needs to be balanced. other than that im just taking suggestions.

[Joes924]

Way to go dude your taken the big step..get a header also and a cam youl freak when you drive it for the 1 st X.

[friskynibbles]

header - no . i've got a turbo.
cam - i am on the list for franco cam gear.

[Rick MacLaren]

Hi Frisky,

You said: "...i plan to have a shop plane the head and maybe the block, hone the cylinders. the flywheel also needs to be balanced. other than that im just taking suggestions."

I had the same choices when I did my rebuild. Here was my reasoning:

1. If you're going to hone the cylinders, you could go the mile and get either new pistons or really consider whether or not you want a rebuild. Like, the problem is, you're putting new rings in, and honing the cylinder walls, but then you're putting in old pistons. It's 'doable', but, man, there are lots of good piston sets out there for $600 USD.

2. Why are you planing the head? To upp your compression? Or to fix a warp? Cause, if it's compression you're after, you probably know, you can only do that so many times. And it's a bugger if they get it wrong. So if compression is your goal, why not get Mahle or other pistons that are also upping the compression. You'll achieve the same ends and still have a head that hasn't been planed.

3. Why plane the head AND deck the block? Isn't that overkill? Again, see New Pistons above.

4. Balancing is a good idea. But it won't matter much if the whole system isn't balanced as a piece...a system: Flywheel, pistons, rings, crank, clutch all at once. Your shop can tell you what they are capable of doing.

You can balance the rods yourself, within a gram, or fraction of a gram. But it's not simple cause you've got more than one direction to balance. It's a day long job with a digital scale or balance beam.

5. If you've got the crank out, consider camphering the oil holes that feed oil into the bearings. That's a nice trick that'll make for a reliable motor.

6. If I were spending the time to make it reliable, I'd go after the head:

A. New valve springs. Cheapo.
B. Check your valves to see if they're within spec.
C. Change your valve guides.
D. Why are you doing the three point grind? Is it out of spec? Like, not meaning to be goofy, but if they're not out of spec, why fix?
E. Check your tappets for straightness and to see if they're within spec. You might consider some new tappets or new adjustment screws.

That should be enough to get more ideas flowing. Good luck.


[ This Message was edited by: Rick MacLaren on 2002-06-30 09:17 ]

[Zuffen]

I Agree with Rick no point in planning the head or decking the block unless mandated due to corrosion or warpage.

Remember compression on a turbo is relative to boost and rpms. You can make many gains there before doing any unreversable machine work

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

[Joes924]

I was suggest that you dont need to plane the head.