[Bummo]

Posted about getting my 915 BB heads on the WEnd. Well, I just checked the exhaust valves with a magnet (cause they looked a little shiny on the tips) and they are non-magnetic...ie stainless (or plastic or wood). I am hoping that means that hard seats are already in place (please, please). I guess that means they may not have been 1.74's stock...they may have been installed replacing the 1.60's. Guess I will have to see if they are installed, then check the bowl to see if its been widend out. Lucky break on the stainless though...perfect for propane in the future.

 

[SeahawkDodge]

I may be wrong here, but I do believe stainless steel is still ferrous (magnetic).... Aluminum and Titanium are not, but Titanium is not normally shiny.

 

[Major Ramifications]

No, most stainless steel is non-magnetic. Some types are magnetic, something about austenitic vs marsensitic or something like that, hell I'm no metalurgist. However, but the fact that they don't stick to the magnet means stainless (or titanium) valves.

 

[Bummo]

Also the heating of the metal to 800 degrees helps restore a non-magnetic state, so the exhaust valves will get lots of that. I think they can go somewhere between 1200 and 1500.

 

[Evildriver-3]

I hate to say it but the cheap and easy back door way out to doing the seats was to use stainless valves, it helped prolong the problem.

I doubt it's titanium but you will know for sure if it weighs nothing, take one out

 

[Bummo]

Yes , thats true. But they look a little high of the bowl floor and a couple dont seem to be perfectly straight (end valve) in the seat vrs valve tip straight line so I am hoping it has seats put in. Seats arent that much money to install, under $200 cdn complete. Also the 915 is kinda hard to get so hopefully somebody took care of it. And it might have started as a 1.6 so seats are more likely then I think. When I get a valve spring compressor I will pull em out.