Guest andythompson Posted February 13, 2006 Report Share Posted February 13, 2006 (edited) I thought this looked very interesting..... http://www.canleyclassics.com/blog/2006/02...nder-heads.html No information on price yet but great to see someone developing it... especially for the more performance orientated punters Edited February 13, 2006 by andythompson Quote Link to post Share on other sites
JRCWeedon Posted February 13, 2006 Report Share Posted February 13, 2006 I would be very very careful before spending loads of cash on an aluminium head. I had a Moss aluminium head on my recently departed TR4 and had quite a lot of problems with head gaskets etc. The issue seemed to be the different rates of expansion of the different materials and the head studs not being able to stretch. Jon Wood of Classic Racecraft said that these heads did not last more than 10mins under racing conditions and certainly my trouble seemed to start at Goodwood test days 4 laps = 8 mins then lots of smoke etc. The racing boys have now reverted to iron heads which says it all. They may however be OK under road conditions. Regards John Quote Link to post Share on other sites
marvmul Posted February 13, 2006 Report Share Posted February 13, 2006 The four cyl TR engines have wet (removable) liners, the 6 cylinders not. Some people have tried to weld the liners of the 4 cyl engine at the top to be able to use the alloy aftermarket cyl head for racing. Don't know if it is succesfull. So it is very well possible that the same problems will not occur with these alloy cylinderheads for the six cyl engine. Quote Link to post Share on other sites
Guest harry dent Posted February 13, 2006 Report Share Posted February 13, 2006 Spoke to Canley Classics today and they are casting the first one tomorrow.This will be fitted to a saloon and will be evaluated through a three month trial( as the car is a every day driver).They have seemed to have done their indepth research well and part of that was to consult top head tuners.I await with antipication in the finished trial and final product. Harry. Quote Link to post Share on other sites
Guest ron Posted February 13, 2006 Report Share Posted February 13, 2006 I don't see any reason why it won't work, there have been plenty cars with CI blocks and alloy heads over the years, price might be the biggest problem! Ron Quote Link to post Share on other sites
Guest andythompson Posted February 14, 2006 Report Share Posted February 14, 2006 Well at least the alloy head is lighter to lift off.... What about the Golf GTI Mk1, Audi 5 cylinder etc... don't remember any significant issues with those headgaskets ... and a similar non crossflow design... maybe the issue is poor coolant maintenance as obviously electrolytic action is more of an issue with alloy / CI. Hopefully Dave will have any problems well sorted with the help of the knowledge base available as this venture should be supported by all true enthusiasts. Alec... any more info on the 60's alloy head? Photo's? Sounds very interesting cheers Andy Quote Link to post Share on other sites
jonlar Posted February 15, 2006 Report Share Posted February 15, 2006 What about the Golf GTI Mk1, Audi 5 cylinder etc... don't remember any significant issues with those headgaskets ... and a similar non crossflow design... maybe the issue is poor coolant maintenance as obviously electrolytic action is more of an issue with alloy / CI. Hi Andy, I think you may have a good point here - I wonder if the old practice of re-torquing a head down after 100 and 500 miles has any bearing on this problem....................? Quote Link to post Share on other sites
Andy Moltu Posted February 16, 2006 Report Share Posted February 16, 2006 Many factors play into head gasket failure and it may well be that the stud arrangement, gasket material and even the elasticity of the studs may be relevant in preventing head gasket failure. Modern cars with iron block & alloy heads were designed with that in mind - the 6 cylinder TR engine was designed for in iron head and may well need other factirs such as head gasket & stud material modifying accordingly. Not sure I'd be in a hurry to spend money on one until the development and testing has been done. Quote Link to post Share on other sites
john.r.davies Posted July 2, 2015 Report Share Posted July 2, 2015 I've always thought that the TR6 engine needed a cross-flow head, so much so that I did drawing of the normal head and ports, to try and work out if it could be done, or if a head from another engine could be adapted. The relative lack of modern six cylinder engines, and the very over-square design of those there are, mainly BMWs, meant I couldn't find one. The recent thread about a TRX for restoration mention that a cross-flow head had been designed for it, and of course Rimmers sell them for earlier TR marks. This thread reveals that Canley's tried to cast some in 2006, but nothing more was heard. Anyone know why? Apart from Andy's educated speculation above. John Quote Link to post Share on other sites
GUY BENNETT Posted July 2, 2015 Report Share Posted July 2, 2015 Iron blocks with alloy heads use stretch bolts. the bolts are used only once. Quote Link to post Share on other sites
Peter Cobbold Posted July 2, 2015 Report Share Posted July 2, 2015 (edited) For slow-revving, road work the greater heat conductivity of aluminium would reduce performance compared with iron, all other features being the same. The compression ratio would need to be increased to compensate, just to recover that loss in thermal efficiency. For knock-limited supercharged engines an alloy head would be useful, even if of the same design as iron. Peter Edited July 2, 2015 by Peter Cobbold Quote Link to post Share on other sites
harrytr5 Posted July 7, 2015 Report Share Posted July 7, 2015 I guess it never happened then? Regards Harry. Quote Link to post Share on other sites
john.r.davies Posted July 7, 2015 Report Share Posted July 7, 2015 Elsewhere, I've been told that the Canley prototypes were a copy of the standard head, not a crossflow, that they all cracked and the project was abandoned. Peter, I think you may be able to answer this The space shuttle airframe was made of aluminium, no doubt a very exotic alloy, but that it needed the ceramic tiles because the alloy had to stay below 175C, or it would weaken. That's what the Wiki says, anyway: https://en.wikipedia.org/wiki/Space_Shuttle_thermal_protection_system). But an aluminium alloy piston must get hotter than that, let alone alloy heads. And Concorde was made of Hiduminium, RR50, developed pre-WW2 to be light and heat resistant, so NASA could have used it. Is that 175C figure just wrong? Wouldn't be first for the Wiki. And, if an alloy head conducts heat away so fast as to cool the chambers, could it do without water cooling? Just have a water jacket in the block? JOhn Quote Link to post Share on other sites
OAF939M Posted July 7, 2015 Report Share Posted July 7, 2015 John, those are erudite and interesting comments. Quote Link to post Share on other sites
Peter Cobbold Posted July 7, 2015 Report Share Posted July 7, 2015 Elsewhere, I've been told that the Canley prototypes were a copy of the standard head, not a crossflow, that they all cracked and the project was abandoned. Peter, I think you may be able to answer this The space shuttle airframe was made of aluminium, no doubt a very exotic alloy, but that it needed the ceramic tiles because the alloy had to stay below 175C, or it would weaken. That's what the Wiki says, anyway: https://en.wikipedia.org/wiki/Space_Shuttle_thermal_protection_system). But an aluminium alloy piston must get hotter than that, let alone alloy heads. And Concorde was made of Hiduminium, RR50, developed pre-WW2 to be light and heat resistant, so NASA could have used it. Is that 175C figure just wrong? Wouldn't be first for the Wiki. And, if an alloy head conducts heat away so fast as to cool the chambers, could it do without water cooling? Just have a water jacket in the block? JOhn John, Don't know about shuttles, and the wiki link looks dead to me. But 175C is very low. 1750C is above melting I reckon. Perhaps it was 1750F .... This is one for RogerH The alloy head has to dump the heat that transfers into it from combustion, into the water jacket and thence to radiator etc. Without water it temperature will rise to that of combustion, and it will melt ! An alloy combustion chamber wall of the same thickness as iron would conduct hear from combustion to water 3 to 4 -fold faster. http://www.engineeringtoolbox.com/thermal-conductivity-metals-d_858.html But aluminium needs to be cast thicker than iron for the same strength so the heat loss would then be ( guessing ) 50 to100% faster. Peter Quote Link to post Share on other sites
sixtynine Posted July 8, 2015 Report Share Posted July 8, 2015 Weren't these over $5000? Quote Link to post Share on other sites
Tim D. Posted July 8, 2015 Report Share Posted July 8, 2015 $5000. What the shuttle? No I think they were way more expensive than that. Tim (i'll get my hat!) Quote Link to post Share on other sites
cp25616 Posted July 8, 2015 Report Share Posted July 8, 2015 At least someone in the UK has decided to evaluate aluminium heads and that has to be admired. If someone in the US decided to do the same and have them made in aluminum (sic) then that would be something entirely different. LOL Alan (remember to cross your t's and dot your i's, if they exist that is) Quote Link to post Share on other sites
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