Alloy Liners

[chris adams 0]

well ive considered and pondered this thought of engineering for a while and if funds were available would give it a go, the thought of ally liners really appeals to me, obviously for the alloy block. has anybody thought of or do use these in their setup?

[rodionski 3 1 Cars]

well ive considered and pondered this thought of engineering for a while and if funds were available would give it a go, the thought of ally liners really appeals to me, obviously for the alloy block. has anybody thought of or do use these in their setup?

 

What will you do with the inner surface? Nikasil, Alusil coating? Acid treated to wash out alloy and expose crystal grids?

 

Have you considered the issues of alloy pistons working with alloy liners?

[chris adams 0]

obviously they will have to be coated in some form or another. and as far as ally piston and ally liner matching its a bonus all round as both the piston and the liner would expand at similar rates which in turn can equate to tighter tolerances and weight reduction ive done quite a bit of research on this subject and found out that they have been used in other engines i think it was a jag or something along those lines, was wondering if anyone has done it on an mi? westwood liners is one site that i got info from.

[chris adams 0]

yes the liners will need some sort of coating which i have not considered which one yet, nikasil is first on the list as my kx 500 runs this type of coating and ally piston and that seems to be a pretty good match. ive researched the idea of ally liner and ally piston quite a lot .a lot of motorbikes run them with no issues at all and im sure ive read that a jaguar run them in in one of there engines before. the reason they didnt stick with the setup was due to cost ie the cast being easier to mass produce and cheaper, the bennefits of using a liner made from the same type of material as the piston means that both components heat up at similar temperatures alowing for tighter toleranses and the obvious need for not over boring the cylinders and over sized rings or pistons. in my opinion its win win apart from the expense i would imagine the price for this setup would be in the region of a grand upwards with the nikal plating. forgive the spelling mistakes

[welshpug 1,657]

Just use an EW block, I think they have steel liners cast into them, rather than the removable ones that XU's used, they are a little lighter.

[chris adams 0]

yes but then im still left with the cast liner which is what my idea is to despose of. was just wondering if anyone else has considered using the idea of ally liners that was my mian question and if i had the money would definatly give this a shot in my mi/gt-6 engine build.

[cammmy 1]

If I was spending that kind of cash I'd probably just get the steel liners from spoox. That would be for maximum strength rather than weight savings though.

 

http://www.spoox.co.uk/catalog/product_inf...3e637447341953e

 

I was talking to a guy with an XJR the other day. He was talking about jag using "soft liners" in one of their V8's and as a result they wore out quicker. Knowing Jag though, that's probably more down to to the quality control (I shouldn't say that though since I have 3 frenchers and a brit made by BL )

[chris adams 0]

i totally agree with you about the cost issues and the spoox items are tried and tested and have proved their quality. im allmost certain if a forged piston made from ally can take so much boost them a liner of the same material would hold up just aswell all said and done its just an idea that i was toying with and just wondered if anyone else had given it any thought.

Edited December 19, 2010 by mi8 turbo

[cammmy 1]

I thought most forged pistons would be steel or some such rather than an aluminium alloy?

 

I'm by no means an expert in this but aren't pistons held away from the bore by the rings? Meaning they don't wear in the same way liners do? Liners have the rings constantly rubbing against them so a softer material would be removed at a greater rate, rather than the big danger being cracking or overheating such as with pistons?

[rodionski 3 1 Cars]

No, all modern pistons (forged or not) are made from ally.

 

And no, if liners are properly treated - they will no longer have ally rubbing against the rings. It will then be either ceramic coating or crystal mesh exposed rather than ally material.

 

However I disagree that liners will hold up just as well as pistons under boost. They will just simply not (this is not to say that they will crack - rather that they will work differently to pistons).

 

Furthermore, I don't think there's a point in going for ally liners for the sake of thermal expansion at all. Especially in a turbo application (give it a wrong ECU tuining at high load and you're setting yourself up not only for piston melting, but also for liner melting)

 

And definitely stock reinforced liners (which are around EUR120 per set from Kolbenschmidt) are a much better route even for boost applications (if you're going for extreme boost - then yes, Spoox steel liners) than going an unknown ally liner route with predictably higher risks and imho close to no gains whatsoever.

[petert1345402284 0]

What's ally?

 

I thought pistons were made from either hypo or hyper eutectic aluminium alloys, depending on whether they're cast or forged. There are some very good alloys around now that allow pistons to be cast without steel expansion struts.

 

Why not just use a cast iron block?

[rodionski 3 1 Cars]

By ally I mean aluminum alloys. I've never seen steel pistons in my life )))

And +1 for the iron block for boost applications.

[cammmy 1]

Learn something new everyday

 

The Kolbenschmidt liners. Do you mean they are the stock XU9J4 liners (which have the extra ribbing that other XU9 liners don't) or that they have extra reinforcement on top of that too?

[chris adams 0]

ally liners have been used in production for quite a few years the first being porsche, bmw, ferrari and some others the porsche 911 turbo was 300 bhp so that goes to show they can handle boost and that was in the 1970s and such materials have come on tenfold since then. as for issues with the jags liners being soft this was due to high sulphar levels in poor grade petroleum back in the day. i think this could be a winner if i had the money or when i do get the money i will give this a go im only lookin for about 350 bhp tops at the end of my project.

Edited December 21, 2010 by mi8 turbo

[cammmy 1]

The cost would be tremendous compared to the gains I think. Would it not be cheaper to get the spoox parts and have a carbon/GRP bonnet made; rather than having completely custom alloy liners made and coated? That would probably save you 15kg or so which I imagine would be a lot more than the liners would get you.

 

 

Edited December 21, 2010 by cammmy

[chris adams 0]

yes the expense is going to be more than the average but thats what will sepeate my engine build from any other QUOTE ( he who dares rodders he who dares ) LOL yea the carbon bonnet is appealing what ever happened to that thread about gettin them ordered are many people still intrested in these or can i get one from somewhere.

Edited December 21, 2010 by mi8 turbo

[chris adams 0]

is there an actual place that makes these panels or are people just doing them as 1 offs, as ive just remembered that there is a carbon fibre manufacturer in my area. a friends son works there and his boss wants him to branch out and do his own products at the mo hes doing a ferrari splitter so maybe if there was enough intrest he could be persuaded to do parts for pugs hmmmmm im very intrested . any one else??????????????????????????????????????????????????????????????????????????????????????????????????????

Edited December 21, 2010 by mi8 turbo

[cammmy 1]

I would be interested but I think by the time freight is factored in, I would unlikely be able to justify it.

[petert1345402284 0]

I've never seen steel pistons in my life ))).

 

Not the whole piston! Turn an Mi16 piston upside down and look inside. There's a steel expansion strut in there.

[chris adams 0]

really ive never seen this i will investigate this immediatly. ill report back later got to go job hunting first wish me luck.

[rodionski 3 1 Cars]

Learn something new everyday

 

The Kolbenschmidt liners. Do you mean they are the stock XU9J4 liners (which have the extra ribbing that other XU9 liners don't) or that they have extra reinforcement on top of that too?

 

Yes, they are stock ribbed liners.

[rodionski 3 1 Cars]

Peter, that I know obviously. I've seen the anti-deformation inserts in the pistons

 

What I have never seen is steel pistons. )))

[chris adams 0]

ok ill take your word for it. we are actually talkin about the piston itself just to clarify as ive not long woke up lol im still ging to have a peek as i never noticed this before, saying that my pistons are in the same dirty state as when i removed them from my liners so maybe thats why i never noticed.

[chris adams 0]

yep i can confirm the standard pistons do indeed have a metal ring running around the inner lower part of the skirt. how odd i wonder what their reasons were for this idea. no doubt it was the same brainiac that decided to put the float on the end of the conrod that connects to the crank journal rather than at the top of the piston like all other xu engines

[rodionski 3 1 Cars]

The reason is thermal expansion. The piston is light enough and uneven in all dimensions, including width of alloy material. It will therefore expand differently when heated. It's expansion and distortion (or rather, anti-distortion) is pre-programmed using, inter alia, such steel inserts.

 

And stop being so cocky about giving names to engineers building the D6C engine. Mind you, this engine is a very close derivative of the Dakar winning 405T16 with the XU8T engine! Obviously they had a reason to build the engine with the floating pin. You'd better first learn why.