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The only place for a coil spring is up Zebedee's arse
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Sorry, yes, Martin is from Liverpool. He used to have 'Brit in Milwaukee' on his signature. I had a lot of communication with him when I got my lifetime ban from rr.net under this username as he was a mod and was fighting my corner for me. Then I registered with a different one and ended up as Admin

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arr that has taken the confusion out of it ,i thought he was an American truck driver, he has a very big rig , i have seen pics of it . he was carting wind turbine blades with it .

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The problem is more that you'll put thousands into a Rover V8 to get it to that state, and its not like its then suddenly reliable. Its still the same engine with many flaws, its just a fresh one. Thats the bit that i'm wary of.

And you right to be wary ... for that you should have never got into a P38, or even a Land Rover in the first place LOL. But we love to have something to deal with every time ....
It is true that the RV8 is an engine with several weak points, but at least they are all well documented and you got plenty specialists that know how to deal with them, after all, is an UK engine and most you guys are in the UK. Abroad in some places might not be that easy. Me here, although in East Europe rebuilding old engines is almost a weekly routing for most mechanics, a very old-school engine such as this, I would not trust anyone to do it.
But there ... after all, one you have sorted a porous block, fitted top hats, machine properly the heads and balance the engine, the rest is really a lesser problem.
And in comparison with having to re-sleeve a BMW lump because the Alusil coating has failed ... now that is the fun!

You can pull a 20 year old M57 out of a scrap E39 and pretty much know it'll just work. It might want a new turbo at some point, but the actual engine is solid. And the same goes for most modern engines. Thus the question, do you spend the time/money making a good Rover V8, or do you instead spend it making some other more reliable modern engine fit instead.

That is a subjective point of view indeed. Is a matter of choosing what problem you want to deal with. For me here, surrounded by people with uncertain projects, changing powerplant would be a matter of several weeks if not months dealing with various people for fab work, electrics connections, and the such, plus my own time, which is very limited. I need my junk to be in running condition, not in an endless loop of technical ecstasy ... for that I already went and started other projects :-(
So for me the answer is easy, stick with the RV8 or change car altogether. Now that is a question ....

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Ah! and no, no way I would go Diesel if I can avoid it ...

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Why bother when he could just buy one off the shelf? See http://www.v8developments.co.uk/50long.htm, good for 350-400bhp depending on cam.

As I said, here lots of people love to spend endless time working and suffering on questionable ideas. I got used to it ...
But my mate is young (half my age!) he is a programmer which means spends all his day in front of the PC, and likes to spend his free time making up stuff .... oh well, we were young once as well !

There's a Brit living in the US that has fitted an LS1 with 4L60e into a P38 and all it needed was an adapter to mate the GM gearbox to the existing transfer case. He's got everything, BeCM, EAS, ABS and all instruments working exactly as they should too. Overfinch used to fit an American V8 (a Ford I think) into the P38 using the original 4HP24.

This is as I wrote above, possibilities given by each place. Here an LS1 is a mirage. BMW stuff is much more common ...

While the BMW engine from the L322 may not be the best and a lot of people complain about the Vanos system, but if doing a conversion you wouldn't put a knackered old engine in, you'd at least rebuild it first. That way it will last just as long as it would have done when new.

Well, here you are presenting again another valid point: how much does it cost to rebuild an M62 compared to an RV8?
If you make some research, is not exactly a cheap proposition ... and again, some things provide questionable results, for example re-sleeving it in case the Alusil (Nikasil in earlier models) fails.
I do not know prices in UK, but here the rebuild list for a M62 is really a high price.

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leolito wrote:

It is true that the RV8 is an engine with several weak points, but at least they are all well documented and you got plenty specialists that know how to deal with them, after all, is an UK engine and most you guys are in the UK. Abroad in some places might not be that easy. Me here, although in East Europe rebuilding old engines is almost a weekly routing for most mechanics, a very old-school engine such as this, I would not trust anyone to do it.
But there ... after all, one you have sorted a porous block, fitted top hats, machine properly the heads and balance the engine, the rest is really a lesser problem.

It depends who you talk to regarding the weak points. I've never heard of anyone with the mythical porous block. I'm not saying they don't exist but not in the quantities some would have you believe. RPi had Cosworth cast some custom blocks that were supposed to cure the problem of coolant leaking around the liners but used the same design as the original engine so didn't really address the problem. However, they spread the story that every 4.6 P38 engine would slip a liner to justify the £8k they wanted for these 'Comcast' blocks. Apparently, according the them, every 4.6 engine will suffer sooner or later as there is less metal between the bores than on the 4.0 litre. Which, as anyone that can read the specs of the two engines will know is complete rubbish, the bores are the same, it is the stroke that is different. Top hat liners will cure the problem completely for around £1,000 to get them fitted. What have you been told about the heads needing to be machined? A bit of gas flowing would improve performance, but there's nothing wrong with the standard heads.

I've said it before and I'll say it again, maintenance is key. For the first 200k of it's life my car was maintained by the police and was fine when I got it despite the abuse they get (something the M57 can't cope with). At 287k it was tired, compression down to around 110psi on all cylinders and was starting to pressurise the cooling system slightly. Not badly but enough to warrant a set of top hats. All that has been done since is regular servicing and it's now up to 493k, so has done over 200k since being rebuilt.

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I think the porous blocks were more of a thing on the ‘03 & ‘04 Disco 2’s. I don’t think P38’s really ever had this issue.

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Also I think that virtually all the porous blocks were made into beer cans long ago.

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... the mythical porous block ...

Thanks for the story, this explains some things I always have wondered. I knew about the Comcast production, and I thought it would be odd not to produce them with top hats, which I to my understanding is the only real solution to an eventual slipping liner ...
I also heard the rumour - and funnily from local mechanics, so imagine how much it has spread - that the 4.0 is a "better" and "stronger" engine because of the material thickness between the bores, but I am like "ah yeah oh ok" .... lol
What I meant in any case is that with simple steps, and well documents, you can resolve the weak areas of the RV8, true or myth to be.
About the heads, I should have specified that if I was to get my engine rebuild, I would do some tune up to them ... :-)

I've said it before and I'll say it again, maintenance is key....

True. Unfortunately, when you buy used, sometimes it can get tricky .... I bought my P38 driven by emotion, not thought, and it costed me dearly.
But the engine ... it is old, tires, 283K km, it has been neglected, it clunks and clonks, leaks oil, eats some antifreeze, but it does not let you down, always pulls. That is why I think in spite of its quirks, it is a loyal beast.
Plus, it is the P38 "unique" engine. It was built for that car, and that car was build for that engine. That remains its signature :-)

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leolito wrote:

Plus, it is the P38 "unique" engine. It was built for that car, and that car was build for that engine. That remains its signature :-)

No it isn't. It was a 1960's Buick design that Rover bought from them. That was in 3.5 litre capacity and used in multiple vehicles (including the Stage 1 Land Rover, Rover SD1, Rover P5B and P6, etc), it went up to 3.9 (3950cc) for the Range Rover and didn't really change for years. For the LWB Classic it was enlarged to 4.2 litre with minor modifications, primarily the cross bolted main bearings as a result of the Iceberg project in collaboration with Perkins trying to make a diesel version. The 3.9 block is externally identical to the 4.0 litre P38 engine and the same 3950 capacity and the 4.0 litre cross bolted block is identical to the 4.6, the only differences between the two is the crank, con rods and pistons. As the 4.0 litre pistons have a smaller dish, a good power mod is to fit 4.0 litre pistons into a 4.6 to give compression of around 10.5:1. Numerous people have used the 4.6 cross bolted block and fitted the front cover and camshaft from the earlier 3.9 so you retain the distributor and 14CUX injection in the larger capacity, stronger, bottom end.

There is a cheap mod to prevent, or even cure the slipping liners, rather than top hat liners. They sit on a cast ridge at the bottom and this can crack allowing the liner to slip down. If the liner is pushed up so sits where it should, a hole can be drilled and tapped through the block and into the base of the liner (below the point where the piston skirt reaches at BDC) and a small bolt or grub screw can then be put through both block and liner so it can't move any longer. It's a bodge but does work.

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FWIW the police engine with issues is the N57, the M57 is the previous generation and seems much more robust. The N series diesels are pretty crap, the 4 cylinder being renowned for eating its timing chains. Certainly one to avoid.

The whole police thing is weird, because they stopped making the N57 in 2015/2016, thus at this point they'd naturally be getting cycled out of the fleet anyway. BMW also appear to be the ones to pull the plug, rather than the police refusing to buy them. As with anything theres probably more complexity than portrayed in the media.

Isnt the "porus block" just another name for the cracking-behind-the-liners issue that they all seem to eventually suffer from?

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It may well be as I can't really see a block going porous.

From what I have seen the problem with the police ones was the way they were being used. They would often be sit idling for hours at a time before being suddenly booted off down the road and run flat out for miles. Not something a normal owner would do. A friend used to work for BMW and he said they are no more reliable than anything else, just that BMW were really good at covering it up. I suspect they decided it would be better to refuse to supply them than risk a well publicised court case.

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I wonder if those that encounter the "slipped liner" syndrome have simply done minimal or no maintenance & allowed the engine to overheat (probably excessively). It also seems to appear more on US than UK forums !! Surely that cannot simply be due to the number of vehicles ?

My project P38 Autobiography was bought cheap because the previous owner suffered "misfire" and ""cooling issues". After stripping the engine, I found blown head gasket, leaking core plugs, a bolt holding the thermostat open, plus over-tightened head bolt threads in the block. since I rebuilt the engine, it starts & runs smoothly, and no longer overheats. CME Bracknell pressure tested the block, and there were zero signs of liner or porous issues.

Can aluminium actually become porous ? I though that would be a casting issue with gasses in the liquid metal ?

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I've worked on several RV8 powered cars never had one with a bad liner, my old mechanic mate has owned more than 30 RV8 V8 powered vehicles and even he said liners weren't what killed them.

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In the US, maintenance seems to be a dirty word and when they try, usually get it wrong. I've imported around 40 cars from the US and long ago realised that all US vehicles should have a label on the bonnet saying "Do Not Open, No User Serviceable Parts Inside". If there is a right way and a wrong way of fitting something, you can guess which way they've done it.

I agree, the easiest way to kill the engine is to allow it to overheat. Rings nip up in the bore so rather than the piston moving in the liner, the liner moves in the block. No different to any other alloy engine with either a steel liner or plated bores, moving parts that are overheated and expand, don't move as well as they were intended.

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As Pete indicated, the blocks don’t become porous. Apparently the last few years that LR made them they didn’t take as much care as they did during most of the years that they built them.

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Considering the age of even the newest P38 I seldom read issues regarding a RV8 totally packing up, on here or other forums sure you get some right basket cases that have had less than a handful of oil changes in its whole life and a cooling systen that was completely neglected, some overheated to the point of pinking etc i'd say for an old V8 they're quite robust, certainly much stronger than the M62 that came in the l322.

As for anything older RRC were odd we used to say the range rover has rotted off the engine as the body/chassis would usually go beyond repair long before the engine gave up ha.

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I think as with anything, a common fault doesnt mean every single one has issues. The aforementioned N47's are a good example of that. A huge number of them having timing chain issues, but there are still plenty driving around. eBays also full of cars with broken timing chains!

I dont think its fair to say they dont have liner issues though. It was enough of an issue even during manufacture that they were x-raying blocks and sorting them based on cylinder wall thickness. Wether you call it cracking or "porosity" its the same thing in the end, water gets thru the alloy cylinder wall, up the back of the liner and into the chamber. The fact that top hat liners exist tell you its enough of a problem that a fix has been developed. If it was a rare problem the fix would be "just get another block"...

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It seems to me that even the slipping liner issue is more of an issue on the D2’s than P38’s. I don’t read much about them on the RR forums, but it seems to happen on the D2 forums I read. The story is that the P38’s got the best blocks every time while some of the D2’s ended up with less perfect ones.

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the D2 only got the 4.0 IIRC? and the rumors go that they used the better blocks for the 4.6, and the worse ones for the 4.0, so i guess it would make sense that you see a higher instance of issues on the D2 simply due to them always getting the poorer blocks, whereas the P38 will have had a lot more 4.6 engines with the better ones.