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Which head ? - Printable Version

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RE: Which head ? - JonE - 06-07-2019

Clive - why bother if you already have a good 37 head which has a decent CR?
Unless you want go-faster looks and an integral water outlet.
Paul - PM Austin in the Shed on this forum. (He also comes up in google searches with his name and Austin 7)


RE: Which head ? - Malcolm Parker - 06-07-2019

I am running both the 1931 saloon and the Ulster on Dave Dyes Ricardo head. The saloon was previously on a bronze Nippy type head and the improvement upon fitting the Ricardo head is very noticeable. The weight saving might also be improving the power to weight ratio!
Go for the Ricardo head, it will pay dividends on any engine. Dave will machine it to suit your engine re compression ratio etc.
I have the larger 18mm plugs in mine, partly as they are more period looking. If your engine is a bit worn and prone to oiling, go for the 18mm plugs, they are much more tolerant.


RE: Which head ? - Ruairidh Dunford - 06-07-2019

The original Ricardo heads I have run are much smoother than the late Ruby Head, they also produce more low down grunt, which I like.


RE: Which head ? - DavidL - 06-07-2019

Motorsport November 1929:

https://www.motorsportmagazine.com/archive/article/november-1929/52/improved-ricardo-head-now-available

Its a "shock absorber" head, whatever one of those is.


RE: Which head ? - Malcolm Parker - 06-07-2019

I assume a 'shock absorber' head is one that minimises 'knocking' or pinking.


RE: Which head ? - Bob Culver - 06-07-2019

CR increments make a big difference so it is important to compare like.
Most s.v heads with a flush squish area are to origianl Ricardo patent so the term is confusing.
A chracteristic of that style of head is that they stir up of the mix so speeds combustion and the engine becomes harsh (and requires less advance). A shock absorber head imay be one tailored to moderate the stir up and hence the shock of combustion.


RE: Which head ? - Austin in the Shed - 06-07-2019

Ricardos idea was to turbulate the air/fuel mixture.Said to be able to run a higher compression ratio without knock,or pinking.We have to remember the fuel quality wasn't that good in the '20's.


RE: Which head ? - Tony Press - 07-07-2019

I know my memory is not the best, but I thought that not long ago the general consensus seemed to be the '1937' cylinder head was a good Ricardo type head (was it designed by Ricardo ?) and equal to if not better than many others. 

See this earlier discussion-

http://pub25.bravenet.com/forum/static/show.php?usernum=2099944454&frmid=5&msgid=1008050&cmd=show&cp=1

which gives this impression.


RE: Which head ? - clive medland - 07-07-2019

Thank you one and all for your contributions. Never fails to amaze me the amount of information / knowledge thats available .
I will order a Ricardo head soon and trust I will fly to Newlands Corner on the next visit !!!


RE: Which head ? - Bob Culver - 07-07-2019

It is probably all on the Internet somewhere, but the Ricardo squish patent was regarded as the saviour of the s.v head, it continuing in some cars to the 1960s at least (Ford Pop, small Studebaker) In the very early 1920s cr for larger motors was only 4:1 or so, limited by pinging. The Ricardo head generally enabled 5:1 which represented a big gain in economy. The early RR Silver Ghost was 3.2:1! To the 1950s at modest rpm many sv engines approached ohv in output  (A40, Minx 100E Ford, Minors) etc) When cr reaches about 7:1 the breathing of a sv head becomes a major limitation. To not speed combustion too much and/or avoid patents, many sv heads did not adopt a fully flush squish area.