Pops' 1997 S6 - 07k BLK WDW

[Hank]

Oh and I agree with the 300-400 rpm decrease in spool. Going from 2.2L to 2.6L made for about 600rpm worth of gain.

[popdemonic]

just one quick and noob question,I'm looking to install a catch can on my car in a very soon.I'm thinking there's too excessive blow by .just curious where did you guy mount the drain flange to the sump?I found 034's catch can provide the flange kits for drain but have no idea where did the flange mount to the sump.

[ChrisAudi80]

just one quick and noob question,I'm looking to install a catch can on my car in a very soon.I'm thinking there's too excessive blow by .just curious where did you guy mount the drain flange to the sump?I found 034's catch can provide the flange kits for drain but have no idea where did the flange mount to the sump.

Pop, no need. I did not connect the drain. The can is always empty.
The PDF says install the oil drain fitting between the turbo oil drain line and pan.

[popdemonic]

just one quick and noob question,I'm looking to install a catch can on my car in a very soon.I'm thinking there's too excessive blow by .just curious where did you guy mount the drain flange to the sump?I found 034's catch can provide the flange kits for drain but have no idea where did the flange mount to the sump.

Pop, no need. I did not connect the drain. The can is always empty.
The PDF says install the oil drain fitting between the turbo oil drain line and pan.

Thanks Chris, I don't think if i installed my the catch can and it's gonna be empty.I saw my intake tract has a lot of
oil in there.A couple choices here.Get the 034 catch can,Mann Provent kits or get the one locally which i 've seen there's a thousand of them available in Thailand and get them welded with the bigger pipes.

[ChrisAudi80]

Or you could find out why you have so much blow by. I agree that making a catch can kit yourself is cheapest. You want to study mine?

btw: Happy Songkran.

[ChrisAudi80]

Sorry for the threadjack chaloux.

[fasterthenrs2]

Sorry to see this, did you blue print the engine what was piston gap before, I actualy did set mine pretty loose, same with ring gaps, high heat expends metals , judging by your description you have had a detonation event, you'll see when pistons be removed, I bet rings are pinched in a ring lands

[Highlander]

Sorry to see this, did you blue print the engine what was piston gap before, I actualy did set mine pretty loose, same with ring gaps, high heat expends metals , judging by your description you have had a detonation event, you'll see when pistons be removed, I bet rings are pinched in a ring lands

There could be some truth in this theory. I remember talking to Marcel about his car
at the last meeting, and if I remember correctly he said that the wastegate has been
full closed for a good portion of the time the car had been driven..........just a thought.

I'd also like to see some pics once it's apart.

Sorry to hear about this guys, I hope you get it back together soon

Cheers,

Craig

[chaloux]

Sorry to see this, did you blue print the engine what was piston gap before, I actualy did set mine pretty loose, same with ring gaps, high heat expends metals , judging by your description you have had a detonation event, you'll see when pistons be removed, I bet rings are pinched in a ring lands

There could be some truth in this theory. I remember talking to Marcel about his car
at the last meeting, and if I remember correctly he said that the wastegate has been
full closed for a good portion of the time the car had been driven..........just a thought.

I'd also like to see some pics once it's apart.

Sorry to hear about this guys, I hope you get it back together soon

Cheers,

Craig

The wastegate was actually fine, I was wrong when I thought it was stuck open. I'm not sure about det, it just doesn't make sense with our tune and fuel. It's coming apart today so we'll see what happened fairly soon. Dad said one thing that was interesting was on cylinder 1, 3, and 5 there was a tiny little nick on the rearmost valve landing... i think that makes it intake valve. Can't remember. Anyway, we'll see!

[chaloux]

So I've been reading about piston slap with forged pistons. There's a video on youtube and a whole bunch of people say "that's normal! forged heats up when warm" etc. etc.

So what is the deal then, how much slap is acceptable? I am pretty dang sure it was all clearanced correctly, but anything is possible I guess. I just know that when we put it together it was NOT loose like that. So it mos'def has changed.


Link to video

[Jamo]

Sorry to hear this, what piston clearance did you use? did you use the JE spec?

[chaloux]

Sorry to hear this, what piston clearance did you use? did you use the JE spec?

Yup, everythign was to the spec JE had on the spec sheet.

[Jamo]

That could well have been the problem as they specify massive clearance which isn't required.

[chaloux]

holy shit. just got back from the shop. Pics/vid will do some explaining.

Few interesting things, mainly the nicks in cyl 1, 3, and 5. Head is perfect. Second there is some scoring in the cylinders. Third is that it appears that the bottom metal layer of the head gasket has cracked between cyl 4 and 5, but dad thinks it happened when he tried to pry it off. Fourth is that dad has his old block complete sitting there looking mighty tempting (stock pistons, RS2 bearings, Pauter rods). It needs one piston to be swapped and at this point we're not sure if we want to put JE pistons back in this motor. Time to call 034 and JE for their opinion.

Pics:

cyl 5


cyl 3


cyl 2 (2 and 4 have no nicks)


cyl 1


Cylinder wall:


Video of slap:

Link to video

My reaction to it all (epic selfshot):

[loxxrider]

yuck

[fasterthenrs2]

It def looks like it got hot in there, few things can cause that, excessive back pressure, detonation, plus hg got lifted (that’s why by pressurizing one cylinder it was running out another one) det or misfire will do that or to high boost on a pump gas. Those pistons are toasted, if bores are in speck (not oval, and scratches are just visual etc) I be not afraid to just hone them right in a car and use it again, what hg gasket is that?? why in one of the pick. it looks like edge of hgg is broken??? You guys didn’t use 82.5mm hg on a 83mm block, I assume.

[fasterthenrs2]

And eah that piston slap is little bit on a excessive side, but with proper rings that should not be a problem, what hgg is that???? in vid you can def see its blown between cylinders

[FRCFD5]

didnt you guys o ring the block?

[Jamo]

Hmm see http://www.s2forum.com/forum/showthread.php?t=5523 I had mine machined like this to remove the area around the recess

[crappyoldaudis]

wow.

urdoinitrong... somehow.

[crappyoldaudis]

oh... stock 3b pistons are forged. They don't slap.

?

[bimmerboy]

Jamo has a good point. Don't B6/B7 S4s have a similar problem with the piston being too thin at the valve relief? I'd say the factory had a good reason to get rid of them on stock pistons.

[fasterthenrs2]

Jamo has a good point. Don't B6/B7 S4s have a similar problem with the piston being too thin at the valve relief? I'd say the factory had a good reason to get rid of them on stock pistons.

Than all of us running JE should be having that problem ;D, it sort of looks like hg is sticking in a combustion chamber, can’t really tell from picks, but it is cracked same spot piston is melted

[Jamo]

[Longitudinal]

Not all forged pistons are the same, crappy. Different alloys and different driving conditions require different amounts of cold piston clearance..