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

[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]

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.

[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]

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.

[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.

[quattrofrank]

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

[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.

[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/

[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