blown 87

Nope, not in the TT, engine speed dependent with the clutch pedal to the floor.

SharkSkin

Greg, what does this mean? AFAIK the design intent is that the flywheel is not part of the overall engine balance and it can be balanced in isolation, without regard to the old FW, the engine, or anything else.

blown 87

I had the rotating assembly balanced when I rebuilt the engine, it was perfect with the auto flywheel, so i will have that exactly matched and take the engine out of the picture, so that just leaves the clutch.

Also, it you look at a flywheel they appear the be externally balanced due to the way they are drilled.

SharkSkin

You didn't have the crank balanced with the flywheel, did you? If you did, then I see the sense in trying to match it.

blown 87

Well, that is the big question, to which i do not have a answer, neither does my machine shop.
All I know is they did not appear to take or add anything to the flywheel, but they did on the rods and crank.

worf928

Is your water bridge powder coated? (Or painted?)

blown 87

Yes, it is, that would be a place to start again I guess.
I thought I cleaned the PC off pretty good when I replaced the temp2 sensor.

SharkSkin

Well, sounds like they properly identified it as internally balanced then. Sucks that there is no paper trail or memory on the issue. I guess the ideal situation is that you discover the AT FW is almost perfectly balanced, in which case you have them balance the new FW as closely as possible and call it a day. If it turns out they balanced the crank/FW together that would really suck. Since the two FWs weigh out so differently it would be pretty tough to match it up.

blown 87

If the engine is internally balanced, the total weight of the flywheel would have little, if any effect on the over all balance of the engine.

All the automatic and manual flywheels sure look to me and my machine shop as being externally balanced from the factory.

blown 87

At worse, I have a extra engine that I can build and start from square one, or I heard that Greg Brown has a couple of motors for sale..........................

It would cost me close to ten grand to do a full rebuild on a 928 engine, less, a lot less if I just did a short block, then it would be a set of gaskets, bearings and some machine work, but it would still be a ton of work.

worf928

Since your idling issue is SO intermittent, it's a long shot, but you could temporarily run an auxiliary ground from the hex-base of the temp-II sensor to a convenient location on the block. If you can catch it doing it's weird idle you can just alligator clip the sensor's base to a ground point and see if the idle changes.

I had an intermittent temp-II ground problem that was 100% due to a poor ground due to PC on the temp-ii contact surface of the bridge. In my case though, the condition always occurred within an hour of the motor being started.

blown 87

I am going to try that next Dave, thanks for the insight.
Sounds like you have been there.
it is frustrating when you can literally fix a thousand cars and the one you own seems to just stand back and laugh at you at times.

worf928

Yours laugh? Mine give me the evil eye. I think they are planning something. I'm scared too.

blown 87

Maybe they are pissed about the Corvettes?
Tis a working theory maybe?

worf928

I think the 'vette is the ring leader. I 'spect they're worried they're going to end up like the Sirocco (not running and in-use as a shelf...)

Hey, never mind me. Get back to your post-op 5-speed before she notices.