Will AQ125 head(1000398), work on AQ151 (1000531)?

[Bricktrouble]

I purchased a head off Ebay that was advertised as an AQ151 head. Turns out, after I had it machined and rebuilt, it's off an AQ125. I'm wondering if they are interchangeable, and if so, what sort of horsepower loss I'm looking at.

 

[dennis461]

have a look here, head should have a number cast into it.
See if it matches your old one.
.
http://forums.turbobricks.com/showthread.php?t=24675

you need to check the cam and make sure it is the 'boat' cam. He may have sold you a automobile head.
Does the head have exhaust port threaded studs or threaded holes?

 

[Bricktrouble]

Hi Dennis, and thanks for the post. The exhaust ports have threaded holes.

Thanks,
Vince.