2.8i Cologne - Leaded or Unleaded?
Discussion
Apologies to those of you who already know this, but for those like me who don't, there's some interesting info HERE relating to earlier 2.8i Colonge engines.
It explains how some earlier heads were fitted with hardened valve seats even though the engine was produced at the time leaded fuel was the norm. The relevant bit is:-
"If they are suitable they are stamped in the centre of the cylinder head exhaust flange. 2.3lt engines will have ‘B’ or ‘F’ stamped on the head 2.8lt engines will have ‘D’ or ‘E’ stamped on them."
Mine has 'EN' cast into the rear exhaust port so I'm not sure how that corresponds to looking for a letter "stamped" in the centre of the "exhaust flange".
Can anyone clarify this?
Thanks in advance
Yes, yes, yes, I know it's weeping oil. I'll sort it out. OK?
It explains how some earlier heads were fitted with hardened valve seats even though the engine was produced at the time leaded fuel was the norm. The relevant bit is:-
"If they are suitable they are stamped in the centre of the cylinder head exhaust flange. 2.3lt engines will have ‘B’ or ‘F’ stamped on the head 2.8lt engines will have ‘D’ or ‘E’ stamped on them."
Mine has 'EN' cast into the rear exhaust port so I'm not sure how that corresponds to looking for a letter "stamped" in the centre of the "exhaust flange".
Can anyone clarify this?
Thanks in advance
Yes, yes, yes, I know it's weeping oil. I'll sort it out. OK?
My understanding is that the letter is stamped onto the exhaust manifold face of the head, and I dont think you can see it with the manifold on. Mind you I have 6 heads in the garage and I am pretty sure there isnt a mark on any of them!
I got asked about this recently and it might help a few people if I add a further note, forgive me if this is teaching grandmother...etc.
The 'old' fuel contained lead which acted in two ways, it tended to help reduce the temperature at valve/seat faces but more importantly it created a slight interface between the valve and the seat when closed. The valve and seat faces run so hot that without that interface there can be a slight amount of microwelding of metal particles of the metals of valve and seat have certain metallic similarities. That is how the erosion takes place. The so called 'hardened' valve seats are of a composition which would not weld to the valve at the temperatures achieved.
Fit unleaded compatible heads and the erosion wont take place.
Add lead or a 'lead replacement' product and the interface is reinstated and erosion wont take place.
At the moment, for the mileage most S's do, lead replacement is the cheaper option. That might well change as the pressure for cleaner fuel increases.
There is however another issue, and that is of the timing of the explosion in the head. If any hot spots develop in the engine then there is the likelyhood of pre-ignition of the mixture. The fuel starts to burn before the spark happens. We usually call it 'pinking'. The design of the Cologne head does render it susceptible to pinking. Sustained pinking will definitely damage the engine.
Changing to 'hardened' valve seats does slightly reduce this as the different composition does apparently conduct heat differently, but the valves still get very hot indeed. If the cylinder head does build up any deposits then 'pinking' is still a possibility. Lead reduced that possibility as does LRP. So an engine with hardened seats may well still exhibit some pinking without high grade petrol of LRP.
I have limited direct experience but one Cologne 2.8 with hardened valve seats was very prone to pinking with 95ron fuel but it went with 97ron fuel or additive!
Incidentally the valve seat recession, once started, tends to accelerate rapidly. One of our members had that happen on a lengthy UK trip. Started with a slight missfire and finished with a ruined head and had to source another.
I got asked about this recently and it might help a few people if I add a further note, forgive me if this is teaching grandmother...etc.
The 'old' fuel contained lead which acted in two ways, it tended to help reduce the temperature at valve/seat faces but more importantly it created a slight interface between the valve and the seat when closed. The valve and seat faces run so hot that without that interface there can be a slight amount of microwelding of metal particles of the metals of valve and seat have certain metallic similarities. That is how the erosion takes place. The so called 'hardened' valve seats are of a composition which would not weld to the valve at the temperatures achieved.
Fit unleaded compatible heads and the erosion wont take place.
Add lead or a 'lead replacement' product and the interface is reinstated and erosion wont take place.
At the moment, for the mileage most S's do, lead replacement is the cheaper option. That might well change as the pressure for cleaner fuel increases.
There is however another issue, and that is of the timing of the explosion in the head. If any hot spots develop in the engine then there is the likelyhood of pre-ignition of the mixture. The fuel starts to burn before the spark happens. We usually call it 'pinking'. The design of the Cologne head does render it susceptible to pinking. Sustained pinking will definitely damage the engine.
Changing to 'hardened' valve seats does slightly reduce this as the different composition does apparently conduct heat differently, but the valves still get very hot indeed. If the cylinder head does build up any deposits then 'pinking' is still a possibility. Lead reduced that possibility as does LRP. So an engine with hardened seats may well still exhibit some pinking without high grade petrol of LRP.
I have limited direct experience but one Cologne 2.8 with hardened valve seats was very prone to pinking with 95ron fuel but it went with 97ron fuel or additive!
Incidentally the valve seat recession, once started, tends to accelerate rapidly. One of our members had that happen on a lengthy UK trip. Started with a slight missfire and finished with a ruined head and had to source another.
Hi...
From my experiencees with 2.8 cologne engines, the casting letters mean nothing in relation to the heads being unleaded or not ! After all how can it be, as those letters were cast in at the point of when the rough castings were made. Its the machining that decides whether they will be finished as unleaded or not. Plus as I am aware, it was only the 2.8efi engine produced in 85/86 as fitted to the jelly mould mk3 Granada, that was a ford produced unleaded unit. And that does not include any 2.8mfi as fitted in Capri/sierra/TvrS etc. I was informed that most of the 700+ efi Granada's were sold as police cars, so I doubt if there will be any good low mileage 'ready to fit' heads around now. Although I could be wrong...
TB.
From my experiencees with 2.8 cologne engines, the casting letters mean nothing in relation to the heads being unleaded or not ! After all how can it be, as those letters were cast in at the point of when the rough castings were made. Its the machining that decides whether they will be finished as unleaded or not. Plus as I am aware, it was only the 2.8efi engine produced in 85/86 as fitted to the jelly mould mk3 Granada, that was a ford produced unleaded unit. And that does not include any 2.8mfi as fitted in Capri/sierra/TvrS etc. I was informed that most of the 700+ efi Granada's were sold as police cars, so I doubt if there will be any good low mileage 'ready to fit' heads around now. Although I could be wrong...
TB.
I am going to try to add a bit more info for 2.8 owners. The results of my research, not just reading up but checking a whole pile of 2.8ltr heads (I have 8 and I have checked a couple of others!)
EXISTANCE OF UNLEADED HEADS. Forget it, only about 700 were made by Ford, for Police use. So you are very unlikely to come across one. The additional letter indicating unleaded was STAMPED into the exhaust port casting after manufacture but it sounds like you are wasting your time looking for it!
CONVERTING TO UNLEADED, it is possible to have hardened seats added to these engines BUT; the casting around the ports is not very precise and cutting back to fit the inserts can result in cutting through the casting or producing a very weak spot. Converted engines need to be pressure tested after conversion, most small engine re-finishers cannot do this or guarantee the engine. If you need to go unleaded then get one done by a specialist (like Burton) who will sell you a tested and guaranteed head on an exchange basis. It ain't cheap!
STAYING WITH ORIGINAL HEADS; it might be possible to run a 2.8 unleaded in a Granada, especially an auto, with little valve seat damage as it will probably not be revved high and the seats/valves are unlikely to get critically hot enough to cause micro welding. In the TVR the revs will be higher and most drivers will use high revs a lot (!). The critical temp will be reached and sustained. Have a look how hot the exhaust stubs, especially the siamesed one, get! Once micro welding starts the rough surface created tends to accelerate the micro welding process.
If you have found that the valve clearances tend to DECREASE with time, especially on exhaust valves near the siamese ports, then you can be pretty sure valve seat recession is happening. It tends to make the tappets quieter! If you catch it early enough the ports and valves can be refaced. But if left, one or ports may recess so far that the recut drops the face of the valve below the face of the cylinder head and it can no longer work efficiently and the head is likely to be scrap.
So it looks like 2.8 owners are best advised to drop the ignition advance by 3% (as much as anything to prevent 'pinking' from starting the micro welding) and keep sticking in the lead replacement additive religiously. Or fork out big money for Burton heads!
Anybody know more or better, please get back on this one.
EXISTANCE OF UNLEADED HEADS. Forget it, only about 700 were made by Ford, for Police use. So you are very unlikely to come across one. The additional letter indicating unleaded was STAMPED into the exhaust port casting after manufacture but it sounds like you are wasting your time looking for it!
CONVERTING TO UNLEADED, it is possible to have hardened seats added to these engines BUT; the casting around the ports is not very precise and cutting back to fit the inserts can result in cutting through the casting or producing a very weak spot. Converted engines need to be pressure tested after conversion, most small engine re-finishers cannot do this or guarantee the engine. If you need to go unleaded then get one done by a specialist (like Burton) who will sell you a tested and guaranteed head on an exchange basis. It ain't cheap!
STAYING WITH ORIGINAL HEADS; it might be possible to run a 2.8 unleaded in a Granada, especially an auto, with little valve seat damage as it will probably not be revved high and the seats/valves are unlikely to get critically hot enough to cause micro welding. In the TVR the revs will be higher and most drivers will use high revs a lot (!). The critical temp will be reached and sustained. Have a look how hot the exhaust stubs, especially the siamesed one, get! Once micro welding starts the rough surface created tends to accelerate the micro welding process.
If you have found that the valve clearances tend to DECREASE with time, especially on exhaust valves near the siamese ports, then you can be pretty sure valve seat recession is happening. It tends to make the tappets quieter! If you catch it early enough the ports and valves can be refaced. But if left, one or ports may recess so far that the recut drops the face of the valve below the face of the cylinder head and it can no longer work efficiently and the head is likely to be scrap.
So it looks like 2.8 owners are best advised to drop the ignition advance by 3% (as much as anything to prevent 'pinking' from starting the micro welding) and keep sticking in the lead replacement additive religiously. Or fork out big money for Burton heads!
Anybody know more or better, please get back on this one.
I think you can check on the V5 the engine number should be listed and shows the D prefix. (mine did)
When the engine had a full recon last year the first thing they checked was if it had UL heads which it does.
I'm sure I remember a letter from TVR stating that all S models were UL compatible. I have left mine at 12° and use 98 UL.
When the engine had a full recon last year the first thing they checked was if it had UL heads which it does.
I'm sure I remember a letter from TVR stating that all S models were UL compatible. I have left mine at 12° and use 98 UL.
Le TVR said:
I think you can check on the V5 the engine number should be listed and shows the D prefix. (mine did)
When the engine had a full recon last year the first thing they checked was if it had UL heads which it does.
I'm sure I remember a letter from TVR stating that all S models were UL compatible. I have left mine at 12° and use 98 UL.
I am afraid the D prefix on the V5 is nothing to do with unleaded. Mine is also coded D and it most definitely doesnt have unleaded heads. I understand the D relates to an age code. The type number for the 2.8i is PRN and it is this which is stamped on the block. However what is stamped on the block, or indeed the cast number on the block, has nothing to do with whether the heads, which are of course separate, are unleaded or not. A type PRN engine could theoretically have either, but in practice the 2.8 engines supplied by Ford to TVR were not fitted with hardened valve seat inserts. When the engine had a full recon last year the first thing they checked was if it had UL heads which it does.
I'm sure I remember a letter from TVR stating that all S models were UL compatible. I have left mine at 12° and use 98 UL.
According to Burton Power, who are the accepted gurus on tuning for engines (and I quote): a 2.8 head which is unleaded compatible will have a D or E stamped on the centre of the cylinder head exhaust flange. I have yet to see one of find anyone who has seen one, including the two engine re-manufacturers I know in Lancashire.
For your 2.8 to have 'unleaded' heads then the heads will have been machined and inserts will have been fitted by a previous owner. Those inserts are easy to see.
Until I see it myself I am not going to believe TVR said the engine was unleaded compatible. It isnt in the Capris of the same age of engine. They may have said it was OK to run on unleaded WITH additive, they may have also advised reducing the advance, as other car clubs did. Our MGB isnt compatible but the club advises on additive and reduced advance.
You have access to 98RON fuel, lucky you! We do not. There is some 97 but it is getting harder to find and the majority is 95. That difference might appear small but it is actually quite significant in terms of the effects on the valves and particularly seats. What is also not well understood is that the RON used in the UK is commonly the rating achieved under ideal test conditions, whereas the RON used in France is that used under actual road test conditions. The UK public is being conned slightly on the actual RON values of pump petrol!
Phillpot, does it make a difference?. Remember this is the 2.8 not the 2.9, the latter engines were all built to be compatible with unleaded.
The problem is that once valve seat recession starts it accelerates quite rapidly. On 95 petrol the 2.8 is prone to 'pink' and that pre-ignition causes localised hot spots ideal for causing micro welding, and once you have a microscopic pit you have the ideal circumstances for a localised hot spot and so it goes on. Most of us give the engines a 'caning' and we are in comparatively high revs more often than the average 2.8 Granada. On one of my heads the siamesed port exhaust valves have recessed 1mm below the head casting when they should be more like 1.5mm above. That is a lot! Once the 'bottom' of the valve V is no longer level with the head casting the air flow efficiency starts to drop quite quickly. To exaggerate it, the valve is now in a short tube with the seat at the bottom, it has to lift further before the annular gap round the valve reaches its full size, and the valve is therefore fully open for less time.
If we treated the engine kindly and burbled around at under 3000rpm all day the 2.8 engine valves would last indefinitely. But what is the fun in that!! Thrash a 2.8 on unleaded without additive and valve seat recession is inevitable.
greymrj said:
You have access to 98RON fuel, lucky you! We do not. There is some 97 but it is getting harder to find and the majority is 95
99RON at Tesco 
97RON is super unleaded. It's at all the stations round here (assuming I'm not missing something?)
I run mine on Super, timed to about 10deg Adv. It's no powerhouse, but then no Cologne-propelled S ever will be. Ticks over quite sweetly, makes a nice noise, brings a smile to the face. That's all I ask
Kitchski said:
99RON at Tesco
97RON is super unleaded. It's at all the stations round here (assuming I'm not missing something?)
Bloody southerners getting the best resources again 97RON is super unleaded. It's at all the stations round here (assuming I'm not missing something?)
. Or maybe they have more 'bangers' needing the 'high' octane fuel 
I have no authoritative information but several major fuel stations locally have dropped 'super' unleaded. None of the four closest to me now stock 97RON and I am running a car designed for 100RON!
Haven't you got a Tesco nearby, Richard?
I buy their "Momentum99" from any of their branches at Stockport, Hattersley, Glossop or Whaley Bridge for about the same price as regular.95 octane from elsewhere.
I also use 97 Ron from my nearby Shell, Esso or BP petrol stations when Percy needs a top-up.
I can't think of any reason there would be no "Siper" around Preston?
I buy their "Momentum99" from any of their branches at Stockport, Hattersley, Glossop or Whaley Bridge for about the same price as regular.95 octane from elsewhere.
I also use 97 Ron from my nearby Shell, Esso or BP petrol stations when Percy needs a top-up.
I can't think of any reason there would be no "Siper" around Preston?
Drop in a 2.9, fiddle with the electrics, buy a couple of manifolds and go a bit quicker. Easy. only took me 2 years to sort it out.
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