Razza Posted November 2, 2015 Report Share Posted November 2, 2015 Hello Everyone I've been using Millers Power Plus for some time but it seems to getting a bit pricey. Would be interested to hear of any alternatives that have been used by other owners. Thanks Quote Link to post Share on other sites
Denis Posted November 2, 2015 Report Share Posted November 2, 2015 Not sure what spec your car is or where you are located....but after years of trying different additives...I found the perfect cure for Pinking in my CP Pi car was a combination of getting my ignition timing set at 11 deg BTDC and using only Shell V-Power + Nitro Unleaded Petrol. Pinking Gone! Quote Link to post Share on other sites
OAF939M Posted November 2, 2015 Report Share Posted November 2, 2015 I just use premium unleaded, Esso in my case but they are probably all the same. Quote Link to post Share on other sites
mike3739 Posted November 2, 2015 Report Share Posted November 2, 2015 Never used any in over 13 years of ownership & an engine rebuild 40,000 miles ago. No issues ever with pinking ever, runs very well on supermarket fuel especially Tesco's cheapest!! Cheers Mike Quote Link to post Share on other sites
Marc R Posted November 2, 2015 Report Share Posted November 2, 2015 W/ or w/o unleaded additive, It may be important to know if your TR6 is a PI or Carb. model. Regards Quote Link to post Share on other sites
Razza Posted November 2, 2015 Author Report Share Posted November 2, 2015 I have no pinking problems etc. but just trying to protect the engine. I thought in an unconverted engine it would cause long term damage to the valve seats if not added to unleaded? There seems to be quite a few brands of additives and I just wondered what others had experienced with other brands. My car is a CP PI too 1970 Cheers Quote Link to post Share on other sites
Marc R Posted November 2, 2015 Report Share Posted November 2, 2015 (edited) On my side for a PI CP w/ Lucas pump, with high octane (Premium 98) no specific additive but few drops of 2 stroke engine oil. Regards Edited November 2, 2015 by Marc R Quote Link to post Share on other sites
rhine Posted November 2, 2015 Report Share Posted November 2, 2015 So thought that lead additives were needed for heads of cars with soft inlet valve seats. The lead provides some protection for the seat and remains for a while if you use unleaded and don't re cut the valves into the seats. This problem goes away when the inlet valve seats are replaced with hard alternatives when a head is converted to run on unleaded. Pinking is a different thing and can be dealt with by using high octane fuel and the appropriate ignition timing. Am sure that there are experts out there who will correct me if I am speaking through my exhaust valve. Richard Quote Link to post Share on other sites
RobH Posted November 2, 2015 Report Share Posted November 2, 2015 Basically you are right Richard - these are two separate issues. Whether there actually is a problem with valve seat regression, given the limited mileage that most of our classics do, is debatable. You also hear stories of hardened valve-seat inserts coming detached or heads cracking because of the metal machined away; so perhaps the cure is dodgier than the disease in some cases? Personally I am soldiering on using Morris Zero Lead, available at around £9 a bottle and which lasts me about three months. Maybe it does something, maybe not but that cost is small alongside all the other running costs so it suits me. Quote Link to post Share on other sites
Marc R Posted November 3, 2015 Report Share Posted November 3, 2015 Good morning, Interesting topic... on a TR6 w/ PI Lucas type and unleaded fuel, I think we must consider 3 parameters: 1/ High compression engine: Risk of pinking! => Use of high octane fuel like Premium 98 2/ Soft inlet valve seats and unhealed compatibility: Risk of seats recession w/ unleaded fuel => Use of lead additives (which one? and is it effective?) or Hardened valve-seat inserts (Cost effective w/ limited mileage?! and impact of heads reliability?!) 3/ PI Lucas system and unleaded compatibility: Compatibility unleaded fuel on Metering Unit and Pump (O ring, membrane and lubrication)?! => Use of compatible Pump and MU (O ring, membranes and setting/adjustment lubrication).Note: On my TR6 PI CP type owned since 1986 and still with Lucal pump, I top up the fuel w/ few drops of 2 stroke oil, maybe a placebo effect nevertheless…. Do not hesitate to comment and correct me, I am on the Forum TRR to share, learn… Best regards Quote Link to post Share on other sites
Denis Posted November 3, 2015 Report Share Posted November 3, 2015 I forgot to mention in my earlier post above that I had my M/U serviced by Neil who would have set it up for Unleaded fuel. Interesting to hear that Hardened Valve Seat Inserts can go bad!...not that I understand why a 'Hardened' Seat is the cure for the absence 'Soft' Lead !!! Anyone? Just a thought, would a lump of Lead in the Fuel Tank help? Quote Link to post Share on other sites
stuart Posted November 3, 2015 Report Share Posted November 3, 2015 Interesting to hear that Hardened Valve Seat Inserts can go bad!...not that I understand why a 'Hardened' Seat is the cure for the absence 'Soft' Lead !!! Anyone? Just a thought, would a lump of Lead in the Fuel Tank help? If the engineering shop is any good then thats extremely unlikely and No Dennis a lump of lead wont do any good! Stuart. Quote Link to post Share on other sites
Penfold Posted November 3, 2015 Report Share Posted November 3, 2015 Although a bit old (2011), there's quite a nice summary to be found at: http://www.classiccars4sale.net/classic-car-how-to-guides/restoration/a-guide-to-unleaded-additives I've heard in the past that the Castrol Valvemaster Plus additive is a good combination of valve seat protection and Octane boost. Not sure if anyone on the forum could vouch for it. http://www.ebay.co.uk/itm/Castrol-Valvemaster-Plus-Lead-Replacement-Petrol-Additive-Octane-Boost-250ml-/161058318369 Quote Link to post Share on other sites
Peter Cobbold Posted November 3, 2015 Report Share Posted November 3, 2015 (edited) I've heard in the past that the Castrol Valvemaster Plus additive is a good combination of valve seat protection and Octane boost. Not sure if anyone on the forum could vouch for it. http://www.ebay.co.uk/itm/Castrol-Valvemaster-Plus-Lead-Replacement-Petrol-Additive-Octane-Boost-250ml-/161058318369 Valvemaster has 1 to 2.5% ferrocene in it. http://msdspds.castrol.com/ussds/amersdsf.nsf/0/B8B04178DCA76D0280257CBB00528220/$file/306744Valvemaster%20Plus.pdf Its an antidetonant ( boosts octane). But ferrocene is not allowed in western pump petrols owing to its wear-promoting properties. http://www.fuelexpert.co.za/dooctaneboosterswork.php It turns ro rust ! Peter Edited November 3, 2015 by Peter Cobbold Quote Link to post Share on other sites
Penfold Posted November 4, 2015 Report Share Posted November 4, 2015 Valvemaster has 1 to 2.5% ferrocene in it. http://msdspds.castrol.com/ussds/amersdsf.nsf/0/B8B04178DCA76D0280257CBB00528220/$file/306744Valvemaster%20Plus.pdf Its an antidetonant ( boosts octane). But ferrocene is not allowed in western pump petrols owing to its wear-promoting properties. http://www.fuelexpert.co.za/dooctaneboosterswork.php It turns ro rust ! Peter Ah! Thanks Peter. This may be why you can't seem to buy Castrol Valvemaster Plus anywhere at all now. They may have withdrawn it completely. There's Millers VSPe but as far as I can tell you need a lot more of it per fill up. I've been buying Wynn's Lead substitute (Halfords) - 250ml bottle treats 250 litres of fuel. Millers appears to be 40 litres fuel per 250ml bottle so I can see why Razza asked his original question. Quote Link to post Share on other sites
Mk1PI Posted November 4, 2015 Report Share Posted November 4, 2015 I use Redline - sodium based - one bottle lasts about 10 refills so very economical - no valve seat wear after many hot and high revving years - I do not treat my engines gently Available in UK from Opie oils I think http://www.opieoils.co.uk/p-1029-red-line-lead-substitute-additive.aspx Quote Link to post Share on other sites
Andy Moltu Posted November 6, 2015 Report Share Posted November 6, 2015 (edited) Good morning, Interesting topic... on a TR6 w/ PI Lucas type and unleaded fuel, I think we must consider 3 parameters: 1/ High compression engine: Risk of pinking! => Use of high octane fuel like Premium 98 2/ Soft inlet valve seats and unhealed compatibility: Risk of seats recession w/ unleaded fuel => Use of lead additives (which one? and is it effective?) or Hardened valve-seat inserts (Cost effective w/ limited mileage?! and impact of heads reliability?!) 3/ PI Lucas system and unleaded compatibility: Compatibility unleaded fuel on Metering Unit and Pump (O ring, membrane and lubrication)?! => Use of compatible Pump and MU (O ring, membranes and setting/adjustment lubrication).Note: On my TR6 PI CP type owned since 1986 and still with Lucal pump, I top up the fuel w/ few drops of 2 stroke oil, maybe a placebo effect nevertheless…. Do not hesitate to comment and correct me, I am on the Forum TRR to share, learn… Best regards The lead is not in itself a factor as far as the PI system is concerned. In the early days of unleaded fuel - the fuel contained relatively high amounts of volatile compounds including benzene which was damaging to the seals in the various Lucas components. In the passing years the amounts of benzene have been reduced and few Lucas Pumps , metering units and injectors remain that have not been rebuilt with viton seals. So the only two concerns are valve seat protection for cylinder heads that have not been rebuilt with harden valve seat inserts and the octane. The cars were originally specified as needing 100 octane fuel which has been gone for decades. The nearest equivalent is super unleaded in the UK which is a notional 97 octane although there is a question as to how todays standards compare to the quoted ones of the 1960s. Regular uleaded is notionally 95 octane but it is rumoured that some fuel companies only blend one fuel and sell it as both their 95 and 97 octane with a premium price for the latter and thus a wider profit margin. This was the case with BP in the past although they now market the two options as different fuels. Is it commercially worthwhile to brew two different ratings with the inherent need to keep separate at the refinery, distribution and at the petrol station. The cynic in me says not for most fuel companies. So any additives may be needed to protect valve seats if the engine has not been modified and possibly boost octane. I say possibly as much pinking isn't fuel related - often being caused by timing scatter from worn distributors and premature low rev advance from slack distributor springs. When these are addressed a lot of cars don't pink even on 95 octane supermarket fuel. Edited November 6, 2015 by andymoltu Quote Link to post Share on other sites
Marc R Posted November 6, 2015 Report Share Posted November 6, 2015 (edited) Hi andymoltu, Thanks' for this set of information on the quality and spec of the fuel, Right now I am a rebuilding phase (Frame, Body, Engine....) - Concerning the engine , I am considering to go for an head upgrade w/ harder seats - Concerning the MU and Pump, I shall certainly send both MU and Pump to Neil Fergusson for a proper recond Regards Edited November 6, 2015 by Marc R Quote Link to post Share on other sites
jean Posted November 7, 2015 Report Share Posted November 7, 2015 Marc,with concern to the valve seats , make sure only the seats on the outlet valves are concerned. As far as I remember the 6 cylinder head shows little space to work the seats. That's the reason why at the beginning some workshop had problems to properly fit inserts which came loose after a certain time. Anyhow if you don't rev the engine high no hardened seats are needed. My 6 has done about 50k miles on a normal cylinder head and no problems up to now. As Mark I add some 2 stroke oil to the fuel, In my case I use 2 stroke marine oil that, to some extend promotes lubrication and inhibits damp in the system. The engine in my 6 is fitted with EFI. As soon as i refill in U.K. I notice slight pinking at high load, strange enough this never occurs at home. Quote Link to post Share on other sites
RogerH Posted November 7, 2015 Report Share Posted November 7, 2015 I forgot to mention in my earlier post above that I had my M/U serviced by Neil who would have set it up for Unleaded fuel. Interesting to hear that Hardened Valve Seat Inserts can go bad!...not that I understand why a 'Hardened' Seat is the cure for the absence 'Soft' Lead !!! Anyone? Just a thought, would a lump of Lead in the Fuel Tank help? Hi Denis, regarding your question of the hard/soft seats. With a normal cast steel head - the exhaust valve seat gets very hot. When the valve crashes into it there is some microscopic welding going on. When the valve is pulled away metal from the head seat is also pulled off (I think this is called 'galling'). It isn't pulled off valve because it is much harder. By using a leaded fuel, or an additive, the valve will strike against this very thin layer of lead and that may be picked up by the valve - leaving the head untouched. Any lead on the valve will get burnt off instantly. So it is the contamination of the lead that stops the welding process - just like a body panel. With a hardened head seat - the material can withstand the high temperature much better and so the impact welding problem disappears. Bit simplistic, but so am I. Roger Quote Link to post Share on other sites
jean Posted November 7, 2015 Report Share Posted November 7, 2015 Well Roger that's a very clever explanation, even I can understand Quote Link to post Share on other sites
Peter Cobbold Posted November 7, 2015 Report Share Posted November 7, 2015 Can't find the details of the FBHVC VSR test but I think they used a BMC A-series run at full throttle and 4000rpm....for hours. Rather extreme treatment compared with a TR in normal driving. Peter Quote Link to post Share on other sites
mike ellis Posted November 7, 2015 Report Share Posted November 7, 2015 My understanding of the action of lead is different from Roger's explanation. In leaded fuel if you estimate there is about 5g lead per gallon and this gallon would do about 100,000 revs the amount of lead in the combustion chamber at any one time is minute. As the melting point is well below combustion temperature it would have to be liquid if was present as lead. What happens is that the combustion product of lead is normally lead oxide which is non volatile and electrically conductive. It would be deposited in the combustion chamber causing pre-ignition and spark plug problems. To counteract this leaded fuel contains scavengers such as ethylene bromide which in the combustion chamber preferentially react with the lead to form lead bromide which is volatile at combustion temperatures and is blown out with the exhaust gases. In my view the 'lead effect' is a bit of a myth. Mike Quote Link to post Share on other sites
Peter Cobbold Posted November 7, 2015 Report Share Posted November 7, 2015 My understanding of the action of lead is different from Roger's explanation. In leaded fuel if you estimate there is about 5g lead per gallon and this gallon would do about 100,000 revs the amount of lead in the combustion chamber at any one time is minute. As the melting point is well below combustion temperature it would have to be liquid if was present as lead. What happens is that the combustion product of lead is normally lead oxide which is non volatile and electrically conductive. It would be deposited in the combustion chamber causing pre-ignition and spark plug problems. To counteract this leaded fuel contains scavengers such as ethylene bromide which in the combustion chamber preferentially react with the lead to form lead bromide which is volatile at combustion temperatures and is blown out with the exhaust gases. In my view the 'lead effect' is a bit of a myth. Mike Mike, Roger's explanation is what I've read in textbooks and on web, eg: http://oldschool.co.nz/2011/forum/index.php?/topic/20751-valve-seat-recession-explained/ And I also agree with your ethylene bromide lead-scavenging action. There must be reason why lead on the valve or seat doesn't get scavenged....high seat temperature maybe? A quandary... Peter Quote Link to post Share on other sites
RogerH Posted November 8, 2015 Report Share Posted November 8, 2015 Hi Mike, your explanation is good as far as the combustion is concerned. My simply picture of what is happening on the seat is good as far as recession is concerned. Going back to your lead and the high temps etc. Many steels have lead in the mix to help with cutting etc When you melt steel and lead together the lead will melt a long while before the steel. As its boiling point is quite high (1750'C) it will be present in the liquid mix along with the steel. This would be the same for the combustion - any lead (whatever its composition) would be molten and could easily get deposited on a surface. This is the contaminant that stops the galling. Unleaded fuel at extreme conditions will kill the seats. Fortunately most club members do not go to these extremes. Roger Quote Link to post Share on other sites
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