Sodium filled exhaust valves? Are they standard fitment to S2's?

[90quattro]

Sodium filled valves are not recomended if you have uprated valve springs and run high rpms.. they have a risk of splitting.

Sodium filled, uprated springs, high rpm, HIGH boost =



ventil-redusert.jpg

Tom Rune

[tscheel]

7A motor

The 7A (and NM) had sodium filled in the beginning at least - see attached image taken from http://www.volkspage.net/technik/ssp/ssp/SSP_93.PDF

Nice collection BTW : http://www.volkspage.net/technik/ssp/index_eng.php/

[UrS4boy]

Is there a check to test if the valves are sodium filled from the outside (without cutting them)?.

Pirvu said "The new 3B valve weights 49.1 gramms, the old 3B has 48.4, the old 7A has 51.7 and the TRW is 51". Sodium filled = about 2 gms lighter.

[quattrofrank]

Sodium filled valves are not recomended if you have uprated valve springs and run high rpms.. they have a risk of splitting.

[Billman]

Is there a check to test if the valves are sodium filled from the outside (without cutting them)?

Also are there people running 7A valves on high HP applications?

I checked at a time the valves with a magnet and the 7A intake valves where strong magnetizing all the way and the exhaust valves not.

[Pirvu Eugen]

The 7A valve i cut was from an engine with the tubular exhaust manifold. I dont know what hapend in the past...but...iff you go to Audi now and order the 611B...you will receive the sodium filled valve.

[UrS4boy]

Thanks so much for posting those photos. At least we know what once was.

The sodium-filled 027109611B exhaust valve = 3B, AAN, ABY and ADU sodium-filled exhaust valves

Note: When you do a cross check on 611B, it also shows up as the 1987 NM and 7A exhaust valves.

To confuse matters more, the non-sodium filled, 027109611D shows up as the NM and 7A exhaust valves also () as far back as 1987.

Maybe the 7As got the 611Bs at the same time that they got the bundle of snakes tubular header - that is until the bean-counters in accounting put a stop to over-building the 7A.

[Pirvu Eugen]

Ahh! Sorry! I forgot to say that on the 7A exhaust valve i cut...except the 027611D mark on top..(over the groove) is..under the groove..the following: T-T 33213 98.
Maybe this is helpful.

[Pirvu Eugen]

Thanks Eugen, this makes interesting reading.... but....

This is worrying and confirms my worst fears...

If you go to Audi, armed with the correct part number for S2 valves - which were originally sodium filled, they will smile and happily sell you (under the same part number) valves which are NOT sodium filled - made by TRW....

BTW Chris...The oem valves i received...i dont know iff are made by TRW or not...but on the stem..i can see only...L-027611B...
on the TRW ones..i see: TRWE YD 33050.....i dont think that they are the same.
Look in my pictures....they are different.

[Pirvu Eugen]

I dont know what to say Chris...but...i ordered mine from Aelred....and he sent me the valves in the oem package and i am pretty sure i received the sodium filled ones.
I will speaq with Aelred...and, iff i can get another valve....i will cut in half one i have allready...but..i am pretty sure they will be sodium filled.
I dont know..iff these are better or not...but i think that Audi has put them into these engines for something.
Will be easy for them to put there some valves...but they didint...sooo i will put my trust into their knoledge.

[LHD_Kid]

Ok!...soo as i promissed!
The 3B valves with the pn. 027 611B on the stem....ARE sodium filled valves.
The 7a with pn: 027 611D are NOT.
In the pictures you can see.
First is ...starting from left: 3B new, 3B old, old 7A and TRW 33050 new.
The next is the 3B new.
Next is the 3B old, then the TRW new, then the 3B and TRW together, then the 3B and 7A old cutted in half and the last is the 3B one alone.
The 3B one has fizzed more than 10 minutes into water.
Ahhh...and: The new 3B valve weights 49.1 gramms, the old 3B has 48.4, the old 7A has 51.7 and the TRW is 51.
I am pretty sure that the TRW is NOT sodium filled.
Hope this helps!
All the best!
Eugen

Thanks Eugen, this makes interesting reading.... but....

This is worrying and confirms my worst fears...

If you go to Audi, armed with the correct part number for S2 valves - which were originally sodium filled, they will smile and happily sell you (under the same part number) valves which are NOT sodium filled - made by TRW....

[Pirvu Eugen]

Ok!...soo as i promissed!
The 3B valves with the pn. 027 611B on the stem....ARE sodium filled valves.
The 7a with pn: 027 611D are NOT.
In the pictures you can see.
First is ...starting from left: 3B new, 3B old, old 7A and TRW 33050 new.
The next is the 3B new.
Next is the 3B old, then the TRW new, then the 3B and TRW together, then the 3B and 7A old cutted in half and the last is the 3B one alone.
The 3B one has fizzed more than 10 minutes into water.
Ahhh...and: The new 3B valve weights 49.1 gramms, the old 3B has 48.4, the old 7A has 51.7 and the TRW is 51.
I am pretty sure that the TRW is NOT sodium filled.
Hope this helps!
All the best!
Eugen

[Wheeljack]

A pic of that would be interesting to see.

They are definitely visibly different, with the sodium valves having the telltale 'tulip' shape for the extra volume. And also anyone who disposes of these SHOULD be cutting them and soaking them in water to react the sodium to protect anyone further down in the recycling chain from injury. They will make nice little bubbles when thrown in a bucket of water.

And, if you are building a performance engine with high rate springs, increased redline, etc., you will NOT want to use the sodium filled valves. The reduced cross sectional area of the neck, due to being hollow, is a major weak point and prone to dropping the valve and causing some serious damage. You'll want some decent inconel or similar exhaust valves in this case.

[Thuppu]

I cut my old valves in half and they were filled with sodium! ABY 1996 engine

A pic of that would be interesting to see.

[4WheelDrifter]

Just weigh the valves, it's pretty obvious if they are sodium filled, or not.

My '91 3B valves are sodium filled, my 7As are not. I'm fairly sure I noted the exact weights of each somewhere.