M96 cylinder scoring
Discussion
Hi all, I recently bought a 02 C4S with high mileage and all seemed ok at first. It now has bad piston slap and needs a rebuild. I have found an engineering company that specialise in engine rebuilds and they have recommended steel liners at a good price for all 6. I have also spoken to other people that say i should have alloy liners but are very expensive. Is there a for and against for steel or alloy liners????.
if all the components in the engine are made from ally, they expand and contract in unison -- put steel liners in and that is compromised. I wouldn't go there - but what is my opinion worth?
...... anyway just putting liners in will probably not be all that is required - see lots of threads elsewhere that relate to the other things that should be done at the same time. Good luck.
...... anyway just putting liners in will probably not be all that is required - see lots of threads elsewhere that relate to the other things that should be done at the same time. Good luck.
BAT71 said:
I have contacted Hartech and I thought they were very expensive. I have not seen any bad feed back about autofarm and their liners. With the amount i would have to pay out for a rebuild would i be better off buying second hand GT3 engine? Will it fit in a 02 C4S?
Used GT3 engine would surely set you back around £15k at least, if you're lucky enough to find one.Autofarm have a good rep, but Hartech have the most experience in the field. Should be fine with either to be honest.
BAT71 said:
I have contacted Hartech and I thought they were very expensive. I have not seen any bad feed back about autofarm and their liners. With the amount i would have to pay out for a rebuild would i be better off buying second hand GT3 engine? Will it fit in a 02 C4S?
I would be surprised if Autofarm were much different on price. Are you comparing apples with apples?mollytherocker said:
BAT71 said:
I have contacted Hartech and I thought they were very expensive. I have not seen any bad feed back about autofarm and their liners. With the amount i would have to pay out for a rebuild would i be better off buying second hand GT3 engine? Will it fit in a 02 C4S?
I would be surprised if Autofarm were much different on price. Are you comparing apples with apples?There really isn't a cheaper alternative, even if one way 'looks' cheaper.
Unless you can get someone to steal it and write it off you're going to have to sell it of cheap or get it fixed properly.
IMO a Hartech engine will increase resale value too.
s_mcneil said:
mollytherocker said:
I would be surprised if Autofarm were much different on price. Are you comparing apples with apples?
Autofarm were more expensive than Hartech, speaking from first hand experience.911p said:
Used GT3 engine would surely set you back around £15k at least, if you're lucky enough to find one.
Autofarm have a good rep, but Hartech have the most experience in the field. Should be fine with either to be honest.
Funnily enough thats near the price Porsche replaced the engine in my 54 C4S for, due to IMS failure.Autofarm have a good rep, but Hartech have the most experience in the field. Should be fine with either to be honest.
As others have said Autofarm or Hartech is the way to go. As much as it sounds good having a GT2 engine in it by the time you've found a good one (?!), assuming you are taking the old one out yourself and not employing the services of a garage (££), fitted the "new" one (with no mounting issues of course!), messed about with the ECU etc and changed all the vehicle documentation then it may seem worthwhile......or not!
Or,
Stick it on a low loader, send it to the one of the above mentioned garages and put the kettle on.
legaleagleboy said:
if all the components in the engine are made from ally, they expand and contract in unison -- put steel liners in and that is compromised. I wouldn't go there - but what is my opinion worth?
......
Machine block, heat block in oven, freeze liners, press liners in, face block/liners, pay big money. What could go wrong.................
The only reason i asked about autofarm or hartech is that Hartech use alloy liners and Autofarm use steel. I can see that ally liners should expand and contract the same as the block and the head. I have not seen any horror stories of Autofarm steel liners. If the steel liners are ok there is a engineering company near me that do alot of the machining work for recon and race engines etc. They gave me a rough price of £1800 for all six using Nikasil liners. They have been around for years and have a good reputation.
BAT71 said:
If the steel liners are ok there is a engineering company near me that do alot of the machining work for recon and race engines etc. They gave me a rough price of £1800 for all six using Nikasil liners. They have been around for years and have a good reputation.
Capricorn ?.petop said:
Funnily enough thats near the price Porsche replaced the engine in my 54 C4S for, due to IMS failure.
Bear in mind that's for the block sitting on a crate, you then need to sort out fitting and as you say all the ancillaries (ECU, clutch, transmission, induction, cooling and I'm sure much more). Probably looking at well into £20k+ by the time you're finished, better off just buying a GT3 in the first place!If extra performance is your thing then a 3.9L upgrade with Schrick cams is probably the way to go at Autofarm.
The company I was thinking of using is Gosnay's in romford. They did mention about the 3.9 conversion,they would sleeve and supply the pistons. Apart from new cams would anything else need modifying?.
I still cant find any horror stories about steel liner failures,Hartech seem to be the only company using ally ones.
I still cant find any horror stories about steel liner failures,Hartech seem to be the only company using ally ones.
We try hard to avoid criticising competitors - it is always regarded as bad form and anyway there are different ways to do things and plenty of work for everyone and I have no specific issues with Autofarm who do provide what seems to be a viable alternative (and down South).
However I can tell you that we have replaced quite a lot of steel liners - of three different types and from different suppliers and some Porsche specialists will no longer use them because they have suffered problems with deck height and rotation caused by the differential expansion rates.
It is no coincidence that the GT3 and Turbo (that have great reliability records) have almost identical alloy Nikasil liners to ours. As I have said before - steel liners are OK if the basic block design and cooling channels are designed for that purpose. The problem with these engines is a coolant flow/localised temperature problem combined with the Lokasil cylinder bore material that resulted in a complete re-design for Gen 2 engines.
Also to run with steel you must have more cold piston clearance (because they do not expand as much at operating temperatures).
Although a set of our alloy liners costs £700 more (£117 each) it also includes the changes to a closed deck support and alterations to the coolant flow rates.
We also offer to fit anything from 1 to all 6 liners and re-round remaining undamaged standard cylinders (which no one else offers) and convert them to a closed deck system - any of which costs much less than 6 steel liners.
So overall - if you did have all 6 cylinders from us it would cost a little more than steel (for something I think is generally aknowledged as much better technically) but for any other solution from us it would cost less).
We probably could manufacture and fit steel liners and make them work and save a few quid - but I think we approach this from the position that rebuilding the engine is a big job anyway - removal, strip, inspect, clean, machine, rebuild, replace several other parts at the same time - road test etc and we would not like to offer an inferior solution (even if steel liners had worked OK so far from some suppliers or not but bearing in mind that we have replaced several that therefore cost those owners another complete rebuild that could have been avoided). It seems to us the wrong ideology when Porsche themselves have favoured alloy Nikasil liners and went away from steel liners in about 1984 - 30 years ago - but I guess steel is a slightly cheaper option - if that is more important to you.
Baz
However I can tell you that we have replaced quite a lot of steel liners - of three different types and from different suppliers and some Porsche specialists will no longer use them because they have suffered problems with deck height and rotation caused by the differential expansion rates.
It is no coincidence that the GT3 and Turbo (that have great reliability records) have almost identical alloy Nikasil liners to ours. As I have said before - steel liners are OK if the basic block design and cooling channels are designed for that purpose. The problem with these engines is a coolant flow/localised temperature problem combined with the Lokasil cylinder bore material that resulted in a complete re-design for Gen 2 engines.
Also to run with steel you must have more cold piston clearance (because they do not expand as much at operating temperatures).
Although a set of our alloy liners costs £700 more (£117 each) it also includes the changes to a closed deck support and alterations to the coolant flow rates.
We also offer to fit anything from 1 to all 6 liners and re-round remaining undamaged standard cylinders (which no one else offers) and convert them to a closed deck system - any of which costs much less than 6 steel liners.
So overall - if you did have all 6 cylinders from us it would cost a little more than steel (for something I think is generally aknowledged as much better technically) but for any other solution from us it would cost less).
We probably could manufacture and fit steel liners and make them work and save a few quid - but I think we approach this from the position that rebuilding the engine is a big job anyway - removal, strip, inspect, clean, machine, rebuild, replace several other parts at the same time - road test etc and we would not like to offer an inferior solution (even if steel liners had worked OK so far from some suppliers or not but bearing in mind that we have replaced several that therefore cost those owners another complete rebuild that could have been avoided). It seems to us the wrong ideology when Porsche themselves have favoured alloy Nikasil liners and went away from steel liners in about 1984 - 30 years ago - but I guess steel is a slightly cheaper option - if that is more important to you.
Baz
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