BP Engine Valve Locks/Keepers

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Keith Jones
I count 5-s in my sleep
I count 5-s in my sleep
Posts: 329
Joined: Thu Jul 06, 2006 6:30 pm
Location: Waiuku

BP Engine Valve Locks/Keepers

Post by Keith Jones » Fri Jul 31, 2015 5:28 pm

Has anyone out there got an early (94 or 95) BP cylinder head that is stripped down that could do some measurements for me?
I have just got some Cat Cams parts (cams, valve springs and retainers) for my new BP4W race engine. However, the valve retainers they have supplied do not suit the OEM valve locks/keepers. The hole in the retainer is 9.8mm diameter as opposed to the BP4W retainers 8.2mm. Consequently the BP4W valve locks almost fall through the hole in the retainer.
When queried about this Cat advised that they took the retainer dimensions from a hydraulic lifter BP engine, not the solid lifter unit, and I will need the corresponding valve locks.
Having checked the Mazda parts list is would appear that they must have use an early BP05 engine, as the later BP05s use the same retainer/lock combination as the BP4W.
If anyone does have this engine stripped down, could they measure the hole in the retainer and let me know.
Assuming Cat are telling the truth I am therefore in the market for a set of valve locks. I'm happy to do a swap of my BP4W retainers and matching locks for the older locks.
BTW the B6 engine retainers and locks are also based on the 8.2mm hole, but locks are a slightly different profile.
Thanks.

Keith Jones
I count 5-s in my sleep
I count 5-s in my sleep
Posts: 329
Joined: Thu Jul 06, 2006 6:30 pm
Location: Waiuku

Post by Keith Jones » Sun Aug 02, 2015 7:12 pm

All sorted. Managed to get a set of the early BP keepers.

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