6 replies to this topic

[savagemini]

Just bought a 12g 2940 head stamped with the 12g 1805 mk2-3 s head... Ive seen alot of things on forums about this head but got a few questions of my own.
Does this head (11 stud) fit a later 1300a+ (9 stud) block without having to mod anythin? Plus is the head any better than a standard 1300a+ head or are they worse or the same?will i gane or loose power etc...
Thanks for your help..

[savagemini]

Sorry the 12g 1805 head my bad.....

[bmcecosse]

It should have the larger inlet valves. I strongly advise opening up the exhaust valve throats at the guide boss/where it turns the corner - not difficult. Yes - it will fit any 1275 and should give a few more horses.

[savagemini]

Thats goodd to know thank you, is that something i could do myself or? Will that gain anythin from doin that? Thanks again...

[Turbo Phil]

Yes you will see a gain as this is the main "bottleneck" in the port. You need to remove the guide to do a decent job of it though, then the valve seat will need a light recut after installing the guide again. So it's not a simple 5min job.

[Spitz]

While at it I would have hardened valve seats installed for the unleaded gas.

[savagemini]

yeah im gunna speak to my local place to see if he can do that,as ive only had the norm done before unleaded,skimmed etc so fingers crossed!thanks for the help guys...