# Plasma cylinder coating?



## Will Anders (Jun 15, 2004)

There hasn't been much in depth talk about this, so I ask the question is anyone concerned about the durability of this as opposed to the more traditional use of iron sleeves? I'm also concerned about the strength of the cylinders under higher boost levels without the sleeves when tuned with the appropriate supporting hardware. I know Nissan has put a ton of testing and countless hours of development into the new GTR. I probably shouldn't question Nissan or worry about this but it happens to be the only concern I have about the new GTR. If anyone can give some insight on this I would appreciate the information.

Thanks Will


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## doggiehowser (Oct 8, 2007)

I think Wink already made some cautions abt the plasma coating in an earlier post. Hold on...

Here it is..



> They have certainly changed the torque curve shape and pk power point since "we" gave them the project back. This means a few things may have happened 1) They have down costed the valvetrain (we had Titanium inlet valves in for phase 2 for Pk power speed of 6800rpm, rev limit at 7800 rpm), or limited speed to improve Pk power fuel economy 2) They are struggling on turbo match, or 3) there is a performance "up-rate" version due soon






> What do you want to know about the internals? Obviously I have to be a little careful with regards to confidentiality, but there seems to plenty of higher level info being released already.
> 
> With regards to max power, I'd get nervous about 600Bhp! Some of the manufacturing methods have changed since we finished with it (it had Coscast AL heads, block and bedplate, but these are now diecast), but many key components will still be the same such as piston/rings (Hitachi Unicia cast piston with integral oil gallary below the top ring groove carrier), *plasma spray iron bore (this does peel off if pushed too hard)*, same mains, big end, crank etc. The big end bearing temperature is pretty damn high at high engine speed due to the bearing loads and large main bearing size too (this makes it difficult to get sufficient oil flow to the big end, which is why all high speed engines [motorbikes, F1 etc] have centre fed cranks). etc, etc.


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## kismetcapitan (Nov 25, 2005)

bore spray = no overboring the cylinders. Blow the engine, buy a new block.


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## Will Anders (Jun 15, 2004)

kismetcapitan said:


> bore spray = no overboring the cylinders. Blow the engine, buy a new block.



I pretty much figured that, unless you go ahead and machine the block to accept iron sleeves $$$$. I'd like to know if it would hold up to a full bar of boost or little more, no cats with a full after-market exhaust from the turbos back, a better intake system and the proper tuning?


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## MeLLoN Stu (Jun 9, 2005)

kismetcapitan said:


> bore spray = no overboring the cylinders. Blow the engine, buy a new block.


Or of course overbore it and have darton or the like make some new sleeves for it assuming they haven't positioned the cylinders rediculously close together, which I doubt. I'm pretty sure that's not a route many, if any will go down though, or be willing to.
That said, plasma coating does afford manufacturers the opportunity to keep the distances between cylinders shorter, but on a big V6 I'm sure it'll be do-able. 

As for the coating itself, jury's out really. I know of a few OEM high performance engines which feature this coating, including on race bikes, F1 cars, Karts etc and it's been flawless. On a powerful road car, I'd expect it to stand up to the test a hell of a lot better than nikasil and the like, but then again plasma coating is a relatively new technology in comparison.

Plasma coating generally has a much lower coefficient of friction compared to cast iron, and has substantially better wear characteristics, so I'll be interested to see what the piston rings are composed of. Durability wise it's pretty tough stuff, but like any coating time will tell how well it stands up to tuning. I'd be very surprised if 600bhp had it cracking and peeling. I'm still not confident Nissan were testing it on standard power even in the public eye without wanting to speculate, but I'm sure they've at least done some behind the scenes testing with much higher power figures, boost pressures and so on than you'll get with the standard car, not doing so would be suicide. 

In terms of how much power it'll ultimately take before you risk breaking down the coating, I wouldn't like to speculate, but it'll be interesting finding out. Nissan, or rather the folks they chose to do their engine development, I'm sure will have some investigation into it, and obviously have their reasons for using it, but I'm still of the opinion that time will tell, especially when tuning starts. 
I personally can't see it being as openly tuneable as the RB26 ever was, or rather not as cost effective to tune.

The VR certainly seems to pave the way for a spicier model, which will be interesting.


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## Wink (May 29, 2007)

MeLLoN Stu, where did you get you information from? Are you a qualified mechanical engineer?

Nikasil spray coating which is on bikes, F1, etc is what you are describing, and is a trademarked electrodeposited oleophilic nickel matrix silicium carbide coating for engine components, mainly piston engine cylinder liners. It was introduced by Mahle in 1967. It is basically bullet proof expect when in the presence of high sulphur fuel (>350ppm), as the sulphur has a higher affinity for silicon than nickel - Jag and BMW suffered this in certain high suplhur markets, but most 1st world markets are now down at <50ppm sulphur level. We recommended to Nissan to go this route, but it does have some environmental issues during manufacturing, and people are still nervous after what happened to Jag and BMW. 

There are virtually no applications that use plasma coating in racing or otherwise as Nikasil is so easy to do and is extremely robust. The GTR uses a plamsa sprayed iron coating, almost certainly applied using the Ford PTWA process (at least the blocks we did were). If it is applied using this process then it is probably the first ever application using the PTWA method in production (there are other methods such as Plasma from Sulzer Metco, but most still consider it not robust enough yet). Cleanliness of the parent bore before application of the iron is absolutely key, and it does not bond well if there are any problems. Also, when pushed too hard it will peel small strips of iron off (the coating is pretty damn thin), normally at the top ring reversal point, or higher if the edge of the crown contacts the bore. 

"Plasma coating generally has a much lower coefficient of friction compared to cast iron".....probably not much different as it is also iron, "and has substantially better wear characteristics", not really again as is the same stuff expect thinner, "so I'll be interested to see what the piston rings are composed of"...the same ring pack and piston coatings are used as a standatd engine. Actually, for the GTR, the rings had a very tough time so the top ring has a better than PDV coating (can't remember is name, but could find out), with a positive twist too! The plasma spray effectively gives parent bore which is mainly done to improve heat transfer characteristics and save weight. 

We had failures during development but we did bore them out and re-sleeve with iron liners (2mm thick). However, our blocks were originally designed to take 2mm iron liners, and thus the aluminium thickness to the water jacket was 6.5mm nominally when parent bore....with the liners fitted this obviously becomes 4.5mm of AL and 2mm of iron between the outside of the cylinder and the water jacket. For a fully optimised parent bore solution (to improve heat transfer) the water jacket should be moved in 2mm so it becomes 4.5mm from the outside of the cylinder to the water jacket....this means that fitting liners would be pretty much impossible without damaging the water jacket in some way (pressing the liners in would probably crack the wall that is left between liner and water jacket, leading to internal water leaks....the water will find it's way out). 

Distance between cylinders (bore spacing) is not a problem even though it has siamesed bores (no water between bores), although there is probably a cross drilling between bores. Parent bore does enable engine to be made smaller, but for a 60 deg V6 the benefits are marginal as the engine geometry is always governed by the fact that you need a flying web on the crankshaft between opposite cylinders to maintain even firing.


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## Wink (May 29, 2007)

Sorry, they are PVD coated rings....!


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## vex (Aug 26, 2007)

intriguing.. thanx for sharing


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## akasakaR33 (Oct 10, 2005)

Wink - you are a wealth of information! So fascinating - if I could only have passed my quantum mechanics physics class, alas I would have been an engineer too... 

Thanks for posting this! Keep them coming!!


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## Will Anders (Jun 15, 2004)

Wink said:


> MeLLoN Stu, where did you get you information from? Are you a qualified mechanical engineer?
> 
> Nikasil spray coating which is on bikes, F1, etc is what you are describing, and is a trademarked electrodeposited oleophilic nickel matrix silicium carbide coating for engine components, mainly piston engine cylinder liners. It was introduced by Mahle in 1967. It is basically bullet proof expect when in the presence of high sulphur fuel (>350ppm), as the sulphur has a higher affinity for silicon than nickel - Jag and BMW suffered this in certain high suplhur markets, but most 1st world markets are now down at <50ppm sulphur level. We recommended to Nissan to go this route, but it does have some environmental issues during manufacturing, and people are still nervous after what happened to Jag and BMW.
> 
> ...


 Thanks for the insight. So what you're saying is that this coating isn't going to hold up when increasing the cylinder pressure/boost, becuase effectively causing the rings to increase the amount of pressure they apply against the cylinder walls and potentially causing the coating to fail?


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## madadd (Jan 30, 2004)

kismetcapitan said:


> bore spray = no overboring the cylinders. Blow the engine, buy a new block.


Last time I blew an engine up it, I lost a conrod through the side of the block. Aluminium or steel it would still have required a new block.

Answer - Don't blow up the engine. (Maybe i should have stopped driving when that loud banging noise got persistantly worse?!)

...MAd


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## MeLLoN Stu (Jun 9, 2005)

Wink,
forgive the brief nature of my reply, I'll compose a proper response later as it's fascinating stuff, appreciate the information. 
As for myself yes qualified mechanical engineer (amongst other related fields) .

I wasn't referring to nikasil, though admittedly I did overlook your emphasis on iron, apologies. 

Can I just ask out of curiosity, what sort of coating thickness is used?


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## Will Anders (Jun 15, 2004)

Nissan states that the plasma sprayed cylinder liner bores are just 0.15mm thick.


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## Sub Boy (Jan 28, 2008)

Sorry to drag up an old post....

But in reading this there is not enough thickness in the block to bore out and insert sleaves?

What happens later in the R35's life (when I can afford one!) when the engine needs a freshen up, and you need to put new rings in and hone the block?

Will the Plasma coating last that well that you can just put new rings in....Or just pop on down to you local "Plasma Coater's" for a quick spray? LOL!!

....I hope Nissan have thought of this, The big reason the GTR has had a following over the years is not from new car sales!


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## mindlessoath (Nov 30, 2007)

it should last the length of the cars life. however if adding more power or too much power it would change that equation. since nissan japan added an ecu just recently i would say that its ok to add some power and be perfectly fine. also many tuners havent had any issues yet.

i had seen a post from a weird owner who said he made 800whp and said the plasma lined walls melted off at this point. but no proof. so who knows.


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## Nicks_Pop (Jul 12, 2009)

@Wink: As akasakaR33 already said, that post was truly a “wealth of information“. 

@Sub Boy: Thanks tons for pulling up this gem of a thread. Reading what Wink had to say was a great eye opener to say the least – explaining and eliminating a lot of conjecture floating around these days, and that back in 2007 no less!

Frankly, I can’t really see why Wink was refuting MeLLoN Stu’s statement that plasma afforded a:“much lower coefficient of friction compared to cast iron“. Afterall cast iron must have an extremely porous surface by nature, whereas a plasma spray must produce one of the smoothest surfaces possible to obtain, as I believe it is basically just spewing iron ions on the cylinder walls. Now that can’t be porous or rough. The only real problem I can think of regarding plasma coating, is the negative side of that very smoothness, namely the difficulty for oil to leave a film on the cylinder walls. Maybe that would explain Wink’s remark about the GT-R’s top piston ring: 


Wink said:


> Actually, for the GTR, the rings had a very tough time so the top ring has a better than PDV coating (can't remember is name, but could find out), with a positive twist too!


Didn’t he mention that in his experience, the most common place for the plasma lining to fail, if in fact it did, was at the highest contact point of the top ring travel [where it experiences a force shift]?


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## Sub Boy (Jan 28, 2008)

mindlessoath said:


> it should last the length of the cars life. however if adding more power or too much power it would change that equation. since nissan japan added an ecu just recently i would say that its ok to add some power and be perfectly fine. also many tuners havent had any issues yet.
> 
> i had seen a post from a weird owner who said he made 800whp and said the plasma lined walls melted off at this point. but no proof. so who knows.


So in saying that, the coating (if the car is left at factory spec) should last for at least 300,000 k's?:nervous: I have my doubts.

....Now even if I am wrong (which happens most of time!) and the Plasma Coating lasts that long, Surely the rings don't. 

So what happens when the rings need replacing? will the bore still be nice and smooth....And you just bang some new rings in a fire it up?


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## gp900bj (Nov 24, 2008)

Sub Boy said:


> So in saying that, the coating (if the car is left at factory spec) should last for at least 300,000 k's?:nervous: I have my doubts.
> 
> ....Now even if I am wrong (which happens most of time!) and the Plasma Coating lasts that long, Surely the rings don't.
> 
> So what happens when the rings need replacing? will the bore still be nice and smooth....And you just bang some new rings in a fire it up?


I believe it was Wink who suggested that statistically about 90% of motors should last 300,000kms (can't find the exact quote).

These thermal coatings are substantially more wear resistant than cast iron and they have much better oil distribution properties so the ring's wear at a much lower rate than they would in a sleeved motor.

But like i've said before, this is the first time they have been used at these power levels, so only time will tell.


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## Cris (Sep 17, 2007)

Not sure about plasma coatings but nikasil can just be recoated. Had it done on my bike after one of the barrels ate itself. I don't remember it being too expensive.


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## mindlessoath (Nov 30, 2007)

There are a lot of things nissan chose to opt from doing for different reasons. Using winks information engine builders can make this a much better engine.

Also note there are a few sources from nissan that hinted at more powerfull version of the car. We notice that wink had developed a more powerfull engine than what's in our standard r35. So we know it has more in it. Porsche have just ponied up and now 2012 nissan will respond. 2010 well get the spec-m.

Anyways... The plasma spayed on iron ***** will last a very long time. They won't re apply it. It will likely last longer than ur warranty meaning u will have to replace the block or modify it on ur own time and money.

Wink said 600bhp would be cutting it close... That's about 705whp right? Sofar only a small handful of people have gained those numbers and have not had problems yet but we have yet to see the long term of that.


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## mindlessoath (Nov 30, 2007)

SP Engineering and Switzer performance have both tuned the R35 300+ hp over the stock readings using aftermarket parts. they were tuning for saftey. switzer tuned for 322hp increase with race gas. sofar i havent heard any issues yet, but i belive the customer with the race gas is in russia so we may not hear if any issues arise.

i cant say what that is in BHP or whp exactly because each dyno reads very differntly. plus i dunno what the stock bhp and 600bhp differnce that wink is guestimating. could 350 hp gain be the absolute highest the engine can go? btw both transmissions were stock, i belive they updated the cooling for them and the fluid, no launching of course. we have seen front LSD's blow up from this kind of power (about 200hp upgrade over stock) so you will likly have to replace the oil in the diff after a few laps or upgrade the lsd system apparently. the transmission already has parts made for it when it fails, but it would be better to upgrade before it fails because a failure can damage alot more from ricketing parts inside bashing other things. look up ssp and dodson for parts.


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## Jm-Imports (Feb 12, 2007)

wink i need some of your inside knowledge and advice , basically my car am going to go all out pistons, rods,studs,bearings head gaskets etc etc..

i have been pointed in your direction with regards to the sleeves-

what do you recommend i should do power will be a safe and reliable 800-900 is what the aim is..


cheers


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## Jm-Imports (Feb 12, 2007)

gp900bj said:


> I believe it was Wink who suggested that statistically about 90% of motors should last 300,000kms (can't find the exact quote).
> 
> These thermal coatings are substantially more wear resistant than cast iron and they have much better oil distribution properties so the ring's wear at a much lower rate than they would in a sleeved motor.
> 
> But like i've said before, this is the first time they have been used at these power levels, so only time will tell.


could the stock plasma coating last say 100,000 miles ? tuned


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## TAZZMAXX (Mar 9, 2010)

Jm-Imports said:


> could the stock plasma coating last say 100,000 miles ? tuned


I seem to remember reading something about the anticipated life for the coating being 100,000 miles in some of the original Nissan press stuff but can't remember where I saw it.

For info on iron l.i.n.e.r.s, go to Nissan GT-R News - GTRBlog.com and look for this on 12th December 2009 - Gruppe-S / Dynamic AutoSports Sleeve VR38 for Monster GT-R Engine Build.

If you look at the Gruppe-S blog, it shows their 4.3 litre stroker engine with the Darton sleeves. These are used in drag engines running 100psi (7bar) boost. From what I read previously about the Jun stroker crank, it's big bucks. Depends how far you want to go? Good luck with the re-build.


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## Jm-Imports (Feb 12, 2007)

TAZZMAXX said:


> I seem to remember reading something about the anticipated life for the coating being 100,000 miles in some of the original Nissan press stuff but can't remember where I saw it.
> 
> For info on iron l.i.n.e.r.s, go to Nissan GT-R News - GTRBlog.com and look for this on 12th December 2009 - Gruppe-S / Dynamic AutoSports Sleeve VR38 for Monster GT-R Engine Build.
> 
> If you look at the Gruppe-S blog, it shows their 4.3 litre stroker engine with the Darton sleeves. These are used in drag engines running 100psi (7bar) boost. From what I read previously about the Jun stroker crank, it's big bucks. Depends how far you want to go? Good luck with the re-build.


yep cheers for that info..

am kind a hoping we can spray it or darton sleeve it, but i think the original crank is pretty solid.

looking at mine after all the debris and damage it had thrown upon destruction.

my only worry is the cooling if we darton sleeve it or maybe i can get info on a better term of coating the cylinders..(i would prefer that)..


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## mindlessoath (Nov 30, 2007)

wink no longer posts here. he wont be able to help. i have pm'ed him with no response many times.

wink also suggest against boring the engine because of the waterjackets etc... so bad idea and who knows how long until a failure from microscopic cracks will happen.

the stock liners should last in its stock form for 100,000 miles. tuned is a completly differnt story and it depends on the rest of the upgraded parts, ie pistons, intercooler, boost levels and iat heat readings etc. even then no ones tested it. the big turbo tuners are now backing down there hp recomendations due to recent problems (or so it appears).

you can coat them with what wink suggests in these threads... if you read up on that coating you will see its proven already in these situations. if you want more help on the coating subject ask underpressure as he has done it to his VR38. also Jun coats there engines with it too, but i think they bore them out a bit (unsure how these will last or for how long because wink suggests boaring even the slightest could cause implications).


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## Jm-Imports (Feb 12, 2007)

mindlessoath said:


> wink no longer posts here. he wont be able to help. i have pm'ed him with no response many times.
> 
> wink also suggest against boring the engine because of the waterjackets etc... so bad idea and who knows how long until a failure from microscopic cracks will happen.
> 
> ...


yep i think i prefer to coated it if am honest - just need to find someone in uk that does this..


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## TAZZMAXX (Mar 9, 2010)

Jm-Imports said:


> yep cheers for that info..
> 
> am kind a hoping we can spray it or darton sleeve it, but i think the original crank is pretty solid.
> 
> ...


Are you thinking of re-using your original crank? I've just look at your photos in the other thread and would suggest that it might only look like superficial bruising it may have suffered some greater trauma. If you are going to re-furb it, I'd get it checked on a CMM first to see if it has twisted the crank pins out of phase. It's just a suggestion but it would be better to find out now than after you've re-built it.


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## Jm-Imports (Feb 12, 2007)

TAZZMAXX said:


> Are you thinking of re-using your original crank? I've just look at your photos in the other thread and would suggest that it might only look like superficial bruising it may have suffered some greater trauma. If you are going to re-furb it, I'd get it checked on a CMM first to see if it has twisted the crank pins out of phase. It's just a suggestion but it would be better to find out now than after you've re-built it.


i wont use original crank just saying its took some beating lol..


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## TAZZMAXX (Mar 9, 2010)

Jm-Imports said:


> i wont use original crank just saying its took some beating lol..


Glad to hear that, you can now turn it into a glass topped coffee table like the Top Gear one! It'll be a conversation piece anyway.


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## MiGTR (Jul 31, 2007)

Jm-Imports said:


> yep i think i prefer to coated it if am honest - just need to find someone in uk that does this..


There are a few companies that do Nikasil coatings, Capricorn being one that springs to mind. As for Plasma spraying the bores, I think you are going to be hard pushed to find anyone that does it.


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