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And just for the record. The piston slap is due to the rings. Go with a Wiseco piston with zero tolerance and you'll hear nothing. A little more ring gap and you'll here piston slapping.
May i ask what do you mean by saying zero tolerance? I am asking because Wiseco only offers 2618 alloy pistons, and all the 2618 require from "nature" a large tolerance.
 

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Themis
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Discussion Starter #482
Themis i understand your 250bhp figure, but are you prepared to see on a dyno what top power this engine will take, within the limits of sensors and turbo boost ?
Yes, occasionally the JCW will be called to boost over 22psi...and on the dyno of course. (it's been done with my previous engine with no problems...I even have a map with 28psi boost pressure...I might test that as well on the dyno...no I won't)
This engine will take a lot more power than the JCW turbo has to offer...so currently my drawback is the turbo, but it's just right for my intended purpose (tight tracks).

I know a hybrid turbo like yours (or even like Minigarage's) or an RS6 turbo will net me higher numbers, but I want to take one step at a time, I love testing different combinations and I want to have my own experience with the current setup, plus the fact that I want to be able to deal with the power of the engine on turns and not only the odd straights...
 

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You will get your 250BHP with no issues. I had more then that with my S before I did my engine.

The guy being an asshole obviously didn't read your post right. You said you messed up the math and that makes his calculations wrong. Since he used your number that you admitted to miscalculating. I should probably wait till he finds my thread and bashes it and me as well.

To add to the piston discussion I have 2618 alloy forged CP pistons.
The recommended ring gap is as follows (in inches).
Turbo/Nitrous/Supercharger applications- Top Ring:Bore x .0055", Second Ring: .004-.006" bigger then top ring, Oil Ring: min .015"
2618 alloy expand more then 4032 alloy, needing a larger gap upon start. When both pistons expand (and everything was perfect) they would be virtually the same size. I originally wanted 4032 but switched when the pistons I received where not to my standard. I also want to push my engine a little harder then Thepenl, so it was the safe decision.

Just thought I would throw out a little knowledge.
 

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An engine that will produce 100bhp per cylinder maximun would be very safe with 4032 too.
Yes, both pistons should have the same dimensions at working temperature, 2618 and 4032. The engine with the 2618 will consume a lot of oil though (and this till it gets hot enough), it will slap when cold, and in my opinion it's not suited for a car that sees everyday use.
 

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Themis
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1,791 Posts
Discussion Starter #485 (Edited)
You will get your 250BHP with no issues. I had more then that with my S before I did my engine.
To add to the piston discussion I have 2618 alloy forged CP pistons.
The recommended ring gap is as follows (in inches).
Turbo/Nitrous/Supercharger applications- Top Ring:Bore x .0055", Second Ring: .004-.006" bigger then top ring, Oil Ring: min .015"
2618 alloy expand more then 4032 alloy, needing a larger gap upon start. When both pistons expand (and everything was perfect) they would be virtually the same size. I originally wanted 4032 but switched when the pistons I received where not to my standard. I also want to push my engine a little harder then Thepenl, so it was the safe decision.

Just thought I would throw out a little knowledge.
Thanks for the shared info mate.
Yes I know I'll get my 250bhp, I already got more than 250bhp with the previous engine, so no sweat there.
Interested in your project too, once it's ready for dyno tuning give us your insight...

An engine that will produce 100bhp per cylinder maximun would be very safe with 4032 too.
Yes, both pistons should have the same dimensions at working temperature, 2618 and 4032. The engine with the 2618 will consume a lot of oil though (and this till it gets hot enough), it will slap when cold, and in my opinion it's not suited for a car that sees everyday use.
You couldn't have said it better Nick. Spot on comment, exactly what I was thinking.
As said in numerous posts in this thread, my choices were all relevant to everyday use...
 

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Themis
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Discussion Starter #488
I will admit, waiting for the car to warm up for a few minutes was annoying at first, getting used to it now.
It's something you will learn to live with, after some time it's ok...
Having lived with it for many years with other cars, I wasn't in the mood to live it again. Hence the Mahle Motosport piston choice...

Θέμη i was thinking the same thing almost two years back :) I am using Arias 4032.
Νίκο, nice to see reasonable choices of materials intended for certain purposes.
 

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Those lambda sensors are $$$, remember being shocked at the price when I ordered one for ours.

Great thread as usual, can't wait till it's all back together and singing!
 

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Maybe consider replacing the OEM hard oil line, as they have a tendency of leaking at the O-ring in the flex joint. Much easier to do this with the engine out.

Something like this...Turbo Line Kits

I'm sure you could do this with parts and fittings found locally...
 

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Themis
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1,791 Posts
Discussion Starter #498
Maybe consider replacing the OEM hard oil line, as they have a tendency of leaking at the O-ring in the flex joint. Much easier to do this with the engine out.

Something like this...Turbo Line Kits

I'm sure you could do this with parts and fittings found locally...
Thanks for the interest. I'll give your idea a thought, although my opinion is that this hard oil line is a quality part.
 

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Are you going to tap for oil pressure/temp anywhere? I probably should of while I had the engine out but wasn't really thinking about gauges.
 

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Themis
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Discussion Starter #500
Are you going to tap for oil pressure/temp anywhere? I probably should of while I had the engine out but wasn't really thinking about gauges.
At this point no, and the reason is I've got another oil exchanger in place of the OEM one which should take care of the oil temps...
Plus, I've enhanced the stock oil pump and managed a slight increase in oil pressure in the oil circuit.
So, I'll just leave these modification work in practice for now.
If my calculations are correct, these two differentiations will be more than adequate for the time being...
 
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