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+--- Thread: which cylinder head?? (/showthread.php?tid=1697)
which cylinder head?? - Michael D - 09-09-2018
Browsing though what's on offer with the several respected specialist, I've come across a choice of cyliderheads that are supposed to enhance performance:
- Ricardo head (out of stock at the moment)
- Alta head - Brough Superior spec (either cast iron or alloy)
- Nippy / Ulster head (iron)
- Whatmogg-Hewitt head (alloy / aluminum)
I'd like to know what these heads have to offer in different aspects (apart from the obvious price differences) and what further changes may be needed when combined with other inlet and exhaust manifolds and a single 1 1/8 SU carb (i.e. ignition advance/retard; fuel mixture etc) ; no search engine has propped up any useful information (even the posts on the old forum I've found are not conclusive).
RE: which cylinder head?? - Charles Levien - 09-09-2018
(09-09-2018, 12:35 PM)Michael D Wrote: Browsing though what's on offer with the several respected specialist, I've come across a choice of cyliderheads that are supposed to enhance performance:
- Ricardo head (out of stock at the moment)
- Alta head - Brough Superior spec (either cast iron or alloy)
- Nippy / Ulster head (iron)
- Whatmogg-Hewitt head (alloy / aluminum)
I'd like to know what these heads have to offer in different aspects (apart from the obvious price differences) and what further changes may be needed when combined with other inlet and exhaust manifolds and a single 1 1/8 SU carb (i.e. ignition advance/retard; fuel mixture etc) ; no search engine has propped up any useful information (even the posts on the old forum I've found are not conclusive).
Dear Michael,
In my experience the standard 37 head is a good starting point — skimmed 10 or 15 thou. to make flat and slightly increase compression ratio. Check it is not already skimmed by measuring depth which is 1.5 ins standard form.
I use a 1.25 SU with no 6 needle and blue spring. Electronic ignition with fixed timing ie bob weights welded together.
Mine is essentially a road car but is
lively enough to take part in the odd sprint or friendly hill climb. Main thing is keeping the weight down and aim for around 30 bhp.
Charles
RE: which cylinder head?? - Michael D - 09-09-2018
thanks Charles... that's a good start especially your tip about the SU no 6 needle and blue spring. I'm not sure the Dutch vintage Sports Car club (indeed my plan is a road going car that can take part in the occasional 'sprint'...) would allow me electronic ignition but let's see.... Only.. keeping the weight down.....slim chance, lost cause ; I come in at. 96 kilo's
RE: which cylinder head?? - Austin in the Shed - 11-09-2018
Hi Michael,I sent you a PM re the heads.
RE: which cylinder head?? - Malcolm Parker - 11-09-2018
Hi Michael
I am using Ricardo heads on my Ulster rep and also the SWB saloon and they are excellent in every respect. When I changed the head on the saloon from a bronze Ulster head to the Ricardo, not only was the engine more lively and tractable, the fuel consumption improved by 3mpg (from 42 to 45) which shows that they must be very efficient.
RE: which cylinder head?? - Charles P - 11-09-2018
(11-09-2018, 06:51 PM)Malcolm Parker Wrote: Hi Michael
I am using Ricardo heads on my Ulster rep and also the SWB saloon and they are excellent in every respect. When I changed the head on the saloon from a bronze Ulster head to the Ricardo, not only was the engine more lively and tractable, the fuel consumption improved by 3mpg (from 42 to 45) which shows that they must be very efficient.
Was that with the same CR Malcolm?
C
RE: which cylinder head?? - Ruairidh Dunford - 12-09-2018
My own favourite is a Whatmough Hewitt - the one I have gives smooth low down torque.
I have noticed that the replicas being made today look identical to mine externally but have a different combustion chamber shape so may not perform in the same way mine does.
Mine is pictured in this thread, along with other interesting and unusual heads:
http://pub25.bravenet.com/forum/static/show.php?usernum=2099944454&frmid=5&msgid=919428&cmd=show
RE: which cylinder head?? - Bob Culver - 12-09-2018
I found decades ago that alloy Seven heads were quite common but had invariably been repeat refaced to some ludicrous c.r.
Comparison one with another really needs to be based on the same c.r. a small difference is significant.
For Sevens and other svs, many variants of the basic Ricardo patent style (as 1937) head are aimed not just at good flow but also at moderating the squish, associated burning rate, and consequent harshness.
RE: which cylinder head?? - Michael D - 12-09-2018
(12-09-2018, 08:03 AM)Ruairidh Dunford Wrote: My own favourite is a Whatmough Hewitt - the one I have gives smooth low down torque.
I have noticed that the replicas being made today look identical to mine externally but have a different combustion chamber shape so may not perform in the same way mine does.
Mine is pictured in this thread, along with other interesting and unusual heads:
http://pub25.bravenet.com/forum/static/show.php?usernum=2099944454&frmid=5&msgid=919428&cmd=show
Hi Ruairidh.... I too had come to the conclusion that a Whatmough Hewitt head would be most value for money so I've contacted the Hon. John Barlow.....whose e-mail was down so we're back to ordering by means of good old snail-mail....
RE: which cylinder head?? - Chris KC - 12-09-2018
For what it's worth I tried quite a few heads in the past and the Speedex was the one I kept on the car. Ultimately though I felt the compression ratio was rather high, so I reverted to the standard '37 type, which is a good all-round head for road use. Aluminium heads are more prone to warping / distortion, worth considering too.