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HA cylinder heads

PostPosted: Sun Dec 09, 2018 1:44 pm
by daveh
Hi there
I have an SL (not a 90) with servo discs, I also have a set of twin carbs on an inlet manifold which fit the car - one of the upgrade merchants when these were new :) .
I am considering putting a high compression, or at least a large valve head on, shouldnt be an obtrusive mod. Does anyone either have one, know of one or can advise on whether the vans all have at least larger exhaust valves (I have heard this but no real proof)

Re: HA cylinder heads

PostPosted: Mon Dec 10, 2018 3:25 am
by jpsmit
Can't help with the head but, you would be better to ask the question either in the General Forum or the Wanted (if you are a member) no one will look here.

good luck!

Re: HA cylinder heads

PostPosted: Mon Dec 10, 2018 6:26 pm
by pbottomley
Only diff is squish, easy to make skim it down ti suit

Compression ratios for 1057cc engines:

Standard engine 8.5:1 (HA20)
low compression engine 7.3:1 (HA20) Vans and optional on saloons
90 engine 9.0:1 (HA21)

HA20 3.175 inches (to 20HA / 253413)
HA20 3.168 inches (from 20HA / 253414)
HA21 3.140


Compression ratios for 1159cc engines:

HB22 8.5:1 & 7.3:1 (7.3:1 low compression optional)
HB23 9.0:1 (90 engine)

HB22 3.185 inches 80.89mm
HB23 3.157 inches 80.19mm