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Discussion Starter #1
So I've brought this up in a few posts that I plan on building a block without sleeves and some nice, lightweight, JE or Wiseco Pistons... I'm really trying to avoid sleeves. Why? For several reasons:

-Iron Sleeves expand at a slower rate than the aluminum pistons which means larger tollorances in the cylnder and that equals less power

-Iron Sleeves create more friction than other alternatives equaling less power

-Iron Sleeve TRAP HEAT in the bore, as Iron is no where near as good of a conductor of heat....and that means less power too...

-Iron sleeves are heavy

OK, so what to do? The MMC in our cylinders is sprayed on. It was devined by Mahl and licensed out to Yamaha for our engines. Needless to say it's hard to get a hold of and it's very messy to work with. It is only a few thousandths thick, can't be bored, and must use iron coated pistons to avoid seizing (iron provides a lubricant to the MMC)...

Ever wonder what the Corvette Race team uses in their cylinders? What about Mercury Racing? What about high-zinging crotch rockets? They all use a Nickel Silicon Carbide plating--- KNown as Nikasil or NiComm. It is applied directly to the aluminum walls and retains many of the GREAT charecteristics of our MMC (tight tollorances, light weight, great heat disipation, durability, etc) and lacks some of the BAD charecteristics. The BAD charecteristics are the way MMC applied (spraying=hard to get and hard to install) and the piston availability (only iron coated Mahl pistons can be used). With NSC plating, the lubricant is in the plating, so a conventional forged piston can be used and sourced from your favorite piston maker.

Other notes: NSC plating is just as, if not more durable than MMC. It's very low friction and can be applied up to .050" thick. That means that after the MMC is bored out of the block, the NSC could bring back the bore to OEM specs-----if so desired. Also, NSC is compatible with all pump fuels and current racing fuels such as those at the track (high sulfer is no problem).

Cost. Cost isn't bad and is comparable to sleeving. Cost is about 600 bucks. That includes removing the MMC coating, applying the plating, hoaning to fit your new pistons, and custom ordering the pistons from JE or Wiseco. Obviously, the actual cost for the pistons is extra, so is shipping.

So here's the catch.... I don't think this has been done on the 2zz.... Perhaps I will be the first to try it--- not sure? NiComm is used on all sorts of race engines and OEM mills including the factory Corevette C6R...

Food for thought...

Best,

Phil
 

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sounds like the people to talk to would be the ones who do the process...
i don't know if the bores could be chrome plated like aviation jugs are, they're actually steel/iron.
i remember taking apart a porsche (356?) back mid sixties and seeing the chrome plating pretty well worn through. i told the fellow "we'll put it together and you can sell it". neither of us had the kind of $ to re-do the set.
as i recall....long time ago...they were aluminum.
just a thought, it might be a problem getting the block in the solution....?
sam
 

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So, the obvious question (well, to me anyway), Since Yamaha uses Nikasil in their motorcycle engines, why did they opt for the "very messy to work with" MMC and iron sleeves for our engines?
 

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Discussion Starter #4
sounds like the people to talk to would be the ones who do the process...
I have. US Chrome is the big dog in the industry for this process and they said there's no reason the 2ZZ wouldn't be a great candidate for the NiComm plating. The guys there are super helpful and very technically sound. This isn't a bandaid solution by anymeans...

I believe MMC was introduced to deal with some of the issues that Nikasil had with crappy sulfer-rich fuels we have in the states (although we don't h ave that anymore), as the Nikasil would break down over time when exposed to sulfer. Old Bimmers and P-Cars had this issue for an example... NiComm is similar to Nikasil but has the addition of Carbide that fixed the sulfer weakness found in the Nikasil predecessor... Of course EPA has forced the sulfer content to come down to virtually nothing in recent years (from what I've read).

Best,

Phil
 

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Discussion Starter #5
So, the obvious question (well, to me anyway), Since Yamaha uses Nikasil in their motorcycle engines, why did they opt for the "very messy to work with" MMC and iron sleeves for our engines?

We don't have iron sleeves... Iron sleeves are an aftermarket critter that has been accepted as the only way to fix a buggered up cylinder. The idea behind this is that we can simply bore the jug and plate with Nicom rather than sleeve and end up with a superior product to sleeving...

Cheers,

Phil
 

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interesting though Phil.. eagar to hear more opinions on this.. I do remember reading about Nikasil used in old BMWs..
 

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Discussion Starter #7 (Edited)
Correct on the Bimmers- Nicom is basically an updated of Nikasil. Nikasil is really just a trademark name for the Nickel Silicon plating... NiCom is the same for Nickel Silicon Carbide plating, FWIW....

Anyone have a 2zz block they want to throw my may:D

Cheers,

Phil
 

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Very interesting; please do update the thread if you move forward with this idea.
 

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isn't that the same stuff we use in aircraft bores?
you must use non-chromium coated rings, tho.
some have not and paid dearly.
good luck, sounds like a great idea.
sam
 

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Discussion Starter #12
Cobra,

There's nothing special about the pistons themselves. The hurdle with MMC spray on lining, yes, spray on, is that it lacks silicon that normally acts as a lubricant of sorts between the aluminum surfaces. In the case on the Mahle forged pistons, the piston skirts come with patches of iron (saying iron to keep it simple) that acts as the lubricant. The stock pistons don't have the patch as the Si was cast into them... More back ground, as I understand from some folks "in the know", Mahle invented the MMC spray on lining and sold the process to Yamaha. Interestingly, Mahle is the only piston company making drop in pistons for the MMC lining. I run them in my engine.

You can NOT simply bore the 2zz block and drop in new pistons. You must hire a company like US chrome to bore the block and recoat the sleeves with something like NiComm. With a Nicomm coating, you can buy more conventional wiseco pistons for an example that don't need any special iron lubricating patches. Nicomm is reported to be just as durable as MMC.

Read through this thread and call US Chrome and ask them. They're very receptive and informative.

I have a "spare" block that I may send their way to have this done in the next year or so. Short blocks are so cheap from Toyota, it's almost hard to justify playing with--- that said, if there's time permitting, the US Chrome option would be cheaper than buying a new short block and drop in Mahle low compression pistons... Cheaper by a lot actually...

Best,

Phil
 

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Interesting side note: Besides Bimmers and P-cars, Nikasil was used on Lotus Esprits. I believe it was only on the chargecooled, S-body four bangers (1990-1995). Adding on to PestoDude's question, if Yamaha and Lotus have experience with Nikasil, why use MMC instead? I like the idea, Phil, it just kind of begs the question.

-Brad
 

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Discussion Starter #14
From what I gather, the technology at the OEM level just sort of faded away with the US's high sulfur fuel being the culprit. Nikasil lacked the carbide component of Nicomm and it was sensitive to prolonged exposure to high sulfur fuels which is why the cars that used it in the US were dieing at only 100K miles... Europe didn't have the high sulfur fuel, so it wasn't a problem for them...

That said, we stopped using high sulfur fuels around the turn of the century. Sulfur went from about 200ppm to like 2ppm when the regulation was changed. I wouldn't be surprised if Nikasil hasn't already been making a comeback or if it might start to become popular again...


Best,

Phil


Interesting side note: Besides Bimmers and P-cars, Nikasil was used on Lotus Esprits. I believe it was only on the chargecooled, S-body four bangers (1990-1995). Adding on to PestoDude's question, if Yamaha and Lotus have experience with Nikasil, why use MMC instead? I like the idea, Phil, it just kind of begs the question.

-Brad
 

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Are you 100% sure that the MMC is a coating, and is not throughout the cylinder bores? From the SAE paper it is made clear that it is added during the casting process, which makes me think that it is cast and not coated.
 

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Discussion Starter #16
Yep- It's a bit of the chicken and egg concept. MMC is generic. It's like saying a car has a composite body... What kind of composite... in this case, what kind of MMC...The MMC in the block is the egg for the MMC cylinder liner chicken. The liner won't bond with just any alloy... If you look at the bores of the block, it's very easy to see the different materials. You cannot just bore the block without applying a new liner (even that hasn't been done on the 2zz to my knowledge, although I don't see why it can't be done as long as the overbore is no more than .5-1mm or so)... Without a new liner, the pistons will probably eat through the soft cast block during the break-in process...

Best,

Phil
 

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This discussion is way beyond my knowledge but I enjoy reading this stuff. Thanks Phil and others for posting this kind of technical information.
 

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Just finding this forum & thread. Any update on this over the past decade? Newer threads?
Phil (BOE) has been treating his cylinder walls with Nikasil for as long as I've been here. This thread is 11 years old. You might want to do a little research.

https://www.boefab.com/

San
 
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