mk1-forum.net

Hello chaps,
I have recently aquired a modified big valve 12G940 cylinder head. It's been fitted with larger (37mm) inlet valves, bronze guides and had a porting job. It's been sat in a garage for about 20 years apparently... There is some infomation stamped in the top of the head near the thermostat and I was looking for some help understanding what they mean:

B/S - BoopSpeed or Broadspeed?
2107 - ?
21.5 - Chamber capicity in CC?
025 - Amount it's been skimmed?

Just trying to understand the history of it a little better really, I'd been keen who did the mods originally...
Thanks,
IanM

Bryan Slark

Bryan has a book with all the heads he's ever done, his son does it all now I believe. Bryan used to do my father's race heads and also mine when I raced in Mini7en's. Boopspeed used to do race mini's way back in the 70's 80's Paul Gaymer, he did my father's first mini miglia Boop 5 I think it was.
Head number and CC will be the markings.

Thanks for the repls and information. I have emailed the guys at Slark Engineering, if I get a response I'll update the thread.

Thread update: I got a response from Neil at Slark:

Hi
Yes looks like one my father modified and ties up with our records.

modified in september 1986 for a dave cooper. fast road spec 21.5 cc in the chambers .

hope this helps.

regards Neil Slark

Mystery solved..... I'm keen to see how it performs on the 1293 I've built......

If it doesn't perform it won't be the head holding it back !