Arthur: I just got back from the parts store where I ordered the BP5EFS. The guy showed me a picture of the actual plug and it looks like it will work seeing that the socket has to be 5/8" , not 13/16" like the BP5ES. Also, I couldn't help but notice an "R" on the plug itself under the part number. What's up with that? Oh, also called a motorcycle shop looking for the BP5EFS...the guy talked to me like I was nuts. Saying that car plugs are way too hot for motorcycles, since plugs for bikes are in the 7,8,9 range. I wouldn't know...

RBYCC: I believe since your turbo, you have to go lower on the heat scale. I know this is the case for Audi's with non-factory set ups.