4 replies to this topic

[Hunter2]

Hi,

 

I am stripping the 2nd of 2 Cooper heads 12G295.

 

The First head has standard valves 1.218" Intake, 1.0" Exhaust.

 

The Second head has 1.31" Intake, 1.151 Exhaust.

 

Both could use hardened exhaust seats, almost certainly new guides...so, what about valves?

 

Major suppliers do not seem to have much on offer.

 

Rick/Hunter2

 

This photo the big valve Cooper head with std valves on right for basic comparison.

 

 

The std valve Cooper head after clean up, before crack test.  Test OK, NO cracks.

 

 

[Spider]

The original stock Valve sizes were 1.215" for the Inlet and 1.000" for the Exhaust.

Exhaust Valves in this size should be dead easy to come by, eg;-

 

http://www.minispare...sic/AEA400.aspx

and Inlet Valves;-

http://www.minispare...|Back to search

 

For the head with oversize valves, those are standard 1275 (12G940 type casting) based. While these Valves are readily available, you just need to check the lengths as these maybe too long

 

[Hunter2]

Thanks!

 

The big valves are longer as you and a local Mini man has suggested.

 

Will take a closer look at spring seats.

 

Rick/Hunter2

[eric67]

REC also supply a good selection of valves. It may be worth checking their website;

 

Race Engine Components -  Race Engine Components Car Valve Springs (recvalves.com)

[Hunter2]

Yes,

 

Have engaged in a good exchange of info with REC/G&S.  The head that had the standard valves is not an issue, the G&S inlets at 1.25" and exhausts at 1.06" could readily go in with fresh seat work and new guides.

 

The head that had the 1275 valves is the challenge...whoever did that work did not do a good job.  The 1.31' inlets had fair contact with the seats, the 1.151" exhausts did not...only a very narrow band of contact showing on the back of the valves, and the guides were badly/inaccurately reamed/honed.

 

Of course, without that head in hand, it is very difficult for them to help resolve the issues.  I'll have to keep digging.

 

Rick