Common Rail Steel Pistons

Who wants them? Each one is 150g lighter!! and will take all the pain we can give them

Looking like 2 months until we have the first sets in had, the custom rods are more than 10mm longer so the crank and block will have an easier time too.

I have drawings and the first 2 prototype sets are paid, they are made in Europe, no spurious sources.

exact price depends on Qty but we are looking at around £4000 for a set of pistons and rods, not cheap but cracked pistons are not either!

Ryan

Imo the head is the weak point. If not, you are doing things the wrong way around

Lets wait and see!

a steel piston takes much less heat from chamber than an alu counterpiece simple due to the fact that steel has a way lower coefficient of heat transfer. in other word. the head face chamber temperature will easily go up 50-70 deg because of this. and on a pushed engine with alu pistons, the head cracks because of heat long before the piston.

the only use for a steel piston is for CO2 benefit as less heat is lost. but test have proven this to be ~2% in NEDC fuel consumption.

If you really want to crack good power, use passat pistons with eventually epsilon further reduced to 15:1 or lower and use water injection to keep egt down. keep PCP below 220bar and you can run all day long.

Any for the VE/ PD configurations .. granted we really don't need them, but I'd love some lighter slugs which can handle higher pcps.

Lower compression ratio, no issue of high PCP's

Its funny...I was told last month they wouldnt be available til november. Nice you can get them early.

Finally! :thumbup:

Not many companies out there making (good) Diesel steel pistons to narrow down the field of speculation - Mahle, Federal Mogul, Capricorn out of Germany.

(and this thread is worthless without pics).

Some oems tested them to serve as co2 benefit, although in durability testing many failures caused the ones that did went into to production to be countable on one 1 hand. And non of the applications are high power variants. Passat 240hp, bmw m50d, etc all use alu despite all having an uprated dual flow coolant path in the cyl head.

mrchill said:

Its funny...I was told last month they wouldnt be available til november. Nice you can get them early.

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Who is the from Chris?

Mahle

Rub87 said:

Some oems tested them to serve as co2 benefit, although in durability testing many failures caused the ones that did went into to production to be countable on one 1 hand. And non of the applications are high power variants. Passat 240hp, bmw m50d, etc all use alu despite all having an uprated dual flow coolant path in the cyl head.

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Mercedes use steel pistons since 2014 and New mercedes I6 is going to have steel pistons too. 315HP on 3l is not that bad. And mecedes says there are room for much more with the steel piston for future...
Steel pistons would be found more in the trucks and takes a lot there. A well made steel piston will be way better then all aluminium pistons I have seen and read about.

Ryan what is the maximum combustion pressure they are design for?

Please tell me specefic hp/l in the setup in which they use steel pistons .. Mercedes are in the last wagon of the train lol. bmw makes 380hp/3l since years lmao, Mercedes is too busy switching there entire design/packaging from V6 to I6 that I doubt is much if any development budget left to break a new specefic hp/l barrier. if at all the want to get anal about getting half a gram less CO2 in certification.

even if a steel piston is better (stronger/lighter), it can only be succesful in an engine with thorough good head cooling design. which the VAG 2.0l CR is definately not..

head cracks at moderate power with alu piston, alu pistons had not even the slightest hair crack..



the key to big power is not being able to run 250+ bar PCP. the key is airflow and getting the fuel in there in time. this is where one should spent 5k..

Interesting but there is a point as far as i would go to make power on 2.0 diesel engine.
Curious how it ends regarding the power you will make and of course the time at santapod. Hope is worth it.

Would of been cheaper to buy the CUA engine and tune that one.

Ruben..i have 2 of those heads cracked , 1 bought to cut into pieces for research and see how bigger seats it can take

Ruben how much sustained egt for these crack to occur?

Im with Rueben here, nobody bought steel pistons to make more power - they are a friction reducing upgrade.

And if you do go to them I would certainly be wanting a piston cooling jet/oil pump upgrade to get more oil cooling to them at high loads.

Rub87 said:

Some oems tested them to serve as co2 benefit, although in durability testing many failures caused the ones that did went into to production to be countable on one 1 hand. And non of the applications are high power variants. Passat 240hp, bmw m50d, etc all use alu despite all having an uprated dual flow coolant path in the cyl head.

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Passat 225hp with some t3 limitation kicking in and some soot in the dpf .

So much potential if you were to let it breathe with no dpf though.

I do wonder how long we see before we see steel pistons in BMW 550dx engine?
The new quad turbo is 394hp last I saw it, and I guess it will not stop there if they going to take on audi..
Unfortunate that engine have hard time to take much more...

I do have steel plate in my Mercedes engine otherwise I do wonder if it take the load I gave it in the past, it was well over 230hp/liter. we will see how it will do over 300HP/l and others are even worse but it is also IDI, not that bad for last wagon manufacture

Sure, old engine where made with plenty safety factor. New engine are made with sole reason to bring cost down and have lowest artificial possible co2 score. 50% of all sold benz diesel have renault engine. Says it all no. Conti injectors drift 50% in pilot qty after 2 hours of regen. The reasoning is: they dont make he best inj, but they can make injectors the cheapest.

As I said before, steel pistons could have a use, but putting more thermal strain on already the weakest link (head) just doesnt sound a good way of throwing 4k sterling at.

Well, we assume that steel pistons sold and bought in the aftermarket will be used in properly engineered builds with PCP, EGT, lambda and head thermal management property thought out...

TDIMeister said:

..with PCP, EGT, lambda and head thermal management property thought out...

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Dave, if EGT and PCP are properly thought after there is no need to spend 4k into pistons whose arent the weak link in a highly stressed 2.0 CR. anyone with logical understanding knows that 4k has to be spend onto bigger nozzles and lowering the CR. this will keep PCP below 220 bar and will keep EGT below 900degC. with these 2 parameters met Alu pistons and the CR head will live a long an happy life.

apart from andy I don't anyone has even re-engneered a TDI head wth improved cooling and reduced thermal stress, or did I miss something here?

my point is. run an engine with 900 deg egt and 220 bar for normal useage, lets say 100-250 kph acceleration, like one could daily do plenty of times living/working in germany, one will see piston are not the weak point. Steel pistons absorb only a fraction of the heat as compared to an alu counterpart, stressing the head even more. In other words, for a given specific heat flow into the chamber, and thus quasi iso specific power, the weakest link (head) will get stressed a lot more.

its a lot easier to drop CR one point and live with 220 bar (cost 400 euro CNC guy lets assume) than spend 4k sterling on steel pistons that would net 250bar useable PCP but will crack a head in only a fraction of the mileage.

Well, someone did think about EGT, PCP, head heat transfer, etc., and devised a solution for it, oh about 7 years ago...

http://bit.ly/2otGcp6

And we started talking about steel pistons even longer ago, some nearly 10 years.
http://forums.tdiclub.com/showthread.php?t=196916

I agree that steel pistons are at present an expensive luxury and doesn't solve the basic thermodynamic considerations that should be in any super high-output Diesel engine, but early adoption always comes with a price and I'm just glad steel pistons will finally come to the TDI.

TDIMeister said:

Well, someone did think about EGT, PCP, head heat transfer, etc., and devised a solution for it, oh about 7 years ago...

http://bit.ly/2otGcp6

Click to expand...

Ah, I thought you pointed to those constructors fitting cars with healthy sized ad blue tanks with nice heated lines, which are perfect to be converted for WI

mrchill said:

Mahle

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Mahle Motorsports are not making them, OE i cant be sure of. Where did you hear this?

I agree that dropping these pistons into a mild build and expecting power is just silly, as is tuning a badly engineered engine and hoping the problem wont move to a different component (I.e the Head or Cylinder walls)

I dont plan on running the OE water cooling system or Oil system on a fully built engine and i dont think anyone wanting to spend £4k on pistons will either!

I have the finalised drawings if any interested parties want to take a look.

£4000?

That'd buy you 8 whole engines lol