AEG163 Cylinder Head
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- iain1967s
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Re: AEG163 Cylinder Head
As far as I know, pressed steel rockers were never used on any Mk1 or Mk2 S heads.
All 11-hole Mk1/Mk2 S heads used forged rockers with 1/2 inch lash adjuster nuts.
The timeline is roughly:
AEA691 forged rockers on the 185 [early Mk1] and 163 heads [later Mk1, early Mk2]
AEG426 forged rockers on the raised top 940 S heads [later Mk2, early Mk3]
12G1221 forged rockers on the final flat top 940 S heads [later Mk3]
Pressed steel rockers came in later in the Mk3 S production run [see below].
Cast [sintered] rockers were introduced way later, for A+ 940 heads.
All 11-hole Mk1/Mk2 S heads used forged rockers with 1/2 inch lash adjuster nuts.
The timeline is roughly:
AEA691 forged rockers on the 185 [early Mk1] and 163 heads [later Mk1, early Mk2]
AEG426 forged rockers on the raised top 940 S heads [later Mk2, early Mk3]
12G1221 forged rockers on the final flat top 940 S heads [later Mk3]
Pressed steel rockers came in later in the Mk3 S production run [see below].
Cast [sintered] rockers were introduced way later, for A+ 940 heads.
Last edited by iain1967s on Sun Feb 28, 2021 9:12 pm, edited 1 time in total.
- LarryLebel
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Re: AEG163 Cylinder Head
Way after the 163, but my Mk3 (12G 940) used pressed steel rockers, purchased new 1971. 

- iain1967s
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Re: AEG163 Cylinder Head
Just checked and Parnell says the same for Mk3.
”During the production run, the original forged valve rockers were changed to the pressed steel type.”
Have edited my original post. Learn something new here every day
”During the production run, the original forged valve rockers were changed to the pressed steel type.”
Have edited my original post. Learn something new here every day

- Ronnie
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Re: AEG163 Cylinder Head
There were two types of forged rocker on the S early with like an anvil head, and the later lighter (I believe) with a platform head. I have no idea of change points. 

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Re: AEG163 Cylinder Head
Dug around in my stash and it turns out I found a set- thanks anywayLarryLebel wrote: ↑Sat Feb 27, 2021 6:51 pm Hey Don, I have 4 cast rockers if you need some. How does $20 each sound?