For my verification before I take this BP4W head to the machine shop, It is correct to use the OEM valve spring seat in conjunction with the ST seats, right?

 

When I installed my springs on my bp4w head I did not use any of the OEM stuff I only used what ST supplied. YMMV

 

Seconded.

 

Thank you. I had read some conflicting info on the forums in my research. I called ST and the person I spoke with said to keep the OEM seats with the ST seats. I sent them an email and got a reply stating to use the ST seats only. I'll go with leaving out the OEMs.

 

I bought my ST springs from Supermiata/929 Racing. I called them and asked and was told use only the ST spacers, and do not use the stock ones.