Stainless steel vs oem valves

[cgk_iii]

Putting my cylinder head back together and some how the machine shop that resurfaced my head and regrinded my valves misplaced the valves.. So now im forced to get new ones. I've seen the stainless steel valves on IE motorsport and those are cheaper and according to IE they are more durable. Not sure if i should just stick with oem valves or get the stainless steel valves.

Anyone have experience or any input?

Edit: its a 1990 m20b25 motor and im goin to be running a 274 regrind

[TobyB]

Either will work just fine. The OEM valves are very, very good.
I've raced with them for a decade, and they hold up well.

Stainless has better high- heat resistance, but somewhat less resistance
to galling in the guides, as the OEM are chromed and polished to
reduce wear.

Both will go 100k if they're given new guides and fitted properly.

t

[cgk_iii]

Either will work just fine. The OEM valves are very, very good.
I've raced with them for a decade, and they hold up well.

Stainless has better high- heat resistance, but somewhat less resistance
to galling in the guides, as the OEM are chromed and polished to
reduce wear.

Both will go 100k if they're given new guides and fitted properly.

t

Right on thanks Toby!

[cgk_iii]

So looking on realoem and found a couple different part numbers with which seems to be different valve sizes.. Whats the difference and how can i tell which size to get. Thanks

[cgk_iii]

http://realoem.com/bmw/showparts.do?...66&hg=11&fg=25

[digger]

Either will work just fine. The OEM valves are very, very good.
I've raced with them for a decade, and they hold up well.

Stainless has better high- heat resistance, but somewhat less resistance
to galling in the guides, as the OEM are chromed and polished to
reduce wear.

Both will go 100k if they're given new guides and fitted properly.

t

by OEM do you mean genuine? in my experience aftermarket inlet ones are poorer than genuine ones on the flow bench (and by eye) by about 10CFM out of 170 which is worth paying attention to . nothing a nice back cut wouldn't fix though and get them trued up.

[MR 325]

If the machine shop LOST your valves shouldn't THEY be replacing them?

The IE stainless are good quality but there's definitely nothing wrong with OEM.

Might be time to find a better machine shop. ;)

[dwight]

Lol

[cgk_iii]

If the machine shop LOST your valves shouldn't THEY be replacing them?

The IE stainless are good quality but there's definitely nothing wrong with OEM.

Might be time to find a better machine shop. ;)

Yea the problem is the guy who owns the shop is my neighbor. He claims he have them back to me with my cylinder head but i think i would know if he gave me my valves. There is no invoice it was a "favor" more than anything.

I would let you guys at bimmerheads do all my machine work if i was in LA i love your products. I was supposed to send my engine down there a few months back for the 2.8 m20 build but shit hit the fan.

[TobyB]

by OEM do you mean genuine?

Yep. No experience with aftermarket for M20's...

t