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Old 10-07-2007, 07:59 PM   #1
tino
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Default what size pistons for a sleeved 2.5 ltr

Hey guys,

im looking at getting some pistons for my build.. Then engine will be flange top sleeved..

What size pistons would u guys recomend?? 100mm or 102mm the pistons will be CP with swain tech coating from ron at axis..

And the benefits and drawbacks of either size??

Thanks in advance
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Old 10-07-2007, 09:35 PM   #2
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Depends.... whats the final bore? Its best too ask who's doing the engine work what too get.
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Old 10-07-2007, 09:41 PM   #3
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Quote:
Originally Posted by twigg107 View Post
Depends.... whats the final bore? Its best too ask who's doing the engine work what too get.

The final bore will be suited to wot ever pistons i choose, as i will be sleeving the block. Thus there wont be an issue with the standard liners in terms of thickness.

But will a 102mm piston provide alot more compared to a 100 mm piston..
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Old 10-07-2007, 10:01 PM   #4
mick_the_ginge
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I did 99.5mm in my first sleeved block and 100mm in my new sleeved block. The plan on going a little smaller than what is available on the market is to ensure I could have the block re-honed in the event of a failure. Well guess what.............. yep the block with the 99.5mm's died so i'm having it re-honed for 100mm's

As for power.... can't say.
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Old 10-08-2007, 08:09 AM   #5
jaxscuby
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do the 99.5's..
just like mick..incase something happens
you can upsize to the 100's
and if somethings again you can
upsize to 102's..
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Old 10-08-2007, 09:58 AM   #6
tino
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Quote:
Originally Posted by jaxscuby View Post
do the 99.5's..
just like mick..incase something happens
you can upsize to the 100's
and if somethings again you can
upsize to 102's..
But my block will be sleeved, so it shall be alot stronger compared to the standard liners..

plus i dont want to be rebuilding this engine every so often, i want it to last...

i think the 100s would be the go thus far..
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Old 10-08-2007, 10:45 AM   #7
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Quote:
Originally Posted by tino View Post
But my block will be sleeved, so it shall be alot stronger compared to the standard liners..

plus i dont want to be rebuilding this engine every so often, i want it to last...

i think the 100s would be the go thus far..
Who said anything about the pistons or the sleeves breaking?

Read this -> http://forums.nasioc.com/forums/show....php?t=1244905

100's will be fine as that will still give you room to re-build. A built block does not mean indestructable so you should be planning a re-build at some point
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Old 10-08-2007, 11:33 AM   #8
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you can also do 101.6 and 102
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Old 10-08-2007, 06:09 PM   #9
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I would start out with the smallest piston that the sleeve can do, that way you have more sleeve to bore in the future...
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Old 10-08-2007, 06:12 PM   #10
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I would start with a 99.5mm as you can use an off the shelf piston from whomever makes them. Then if you ever hurt it you can go to the next off the shelf one that is 100mm. This way you dont have to spend 20%+ more on a custom piston.
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Old 10-08-2007, 08:41 PM   #11
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Thanks for the imput guys, under rons suggestion ill stick with the 100mm..
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Old 10-08-2007, 08:48 PM   #12
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Quote:
Originally Posted by mick_the_ginge View Post
Who said anything about the pistons or the sleeves breaking?

Read this -> http://forums.nasioc.com/forums/show....php?t=1244905

100's will be fine as that will still give you room to re-build. A built block does not mean indestructable so you should be planning a re-build at some point


Geez looked like a rod bearing failure there, sorry to hear.. What size bolts did u use??
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Old 10-09-2007, 12:22 AM   #13
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Gasket is 101.6 mm, not sure if you'd need to trim or not, if you were to go above that.
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Old 10-10-2007, 06:42 AM   #14
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We do 102mm sleeved blocks with great success. No issues with 600+WHP
set up's.
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Old 10-10-2007, 11:43 AM   #15
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Quote:
Originally Posted by TJL Performance View Post
We do 102mm sleeved blocks with great success. No issues with 600+WHP
set up's.
Great, but what if something does happen? then what, he goes to 103's (which I know are available) leaving the sleeves thin?

My argument has *nothing* to do with will they work, it's all about planning. I'm pointing out that just having a built block does not mean it's indestructable so planning for a rebuild from the start is good insurance and makes good sense.

How much real HP difference are you going to see on 100's vs 102's? From my experience it's about the same as what you can get from running a different hotside on the turbo or different cams.

TJL how many of these setups have you done? Lets try and quantify what the resulting car has been used for, street, drag, track because this makes a difference.
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Old 10-10-2007, 12:14 PM   #16
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Mick also remember you can remove sleeves and install new. I have never had to do this, but it can be done if need be, at least on the blocks I provide.

- J.
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Old 10-10-2007, 12:17 PM   #17
mick_the_ginge
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Hi Jeremy, correct but if tino is like me and other owners we don't have $$$ laying around and the sleeving machine cost is one of the bigger bills.

OK, enough said from me. Cheers
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Old 10-10-2007, 12:25 PM   #18
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Im just trying to offer some insight and possible solutions.

I have never had to do this process, but I look at it this way.

Of all the parts that go into a sleeved block replacing a sleeve or two or all would be alot cheaper than starting over with a new block.

Remember this should be after a couple rebuilds in which you can remachine the sleeves.

- J.
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Old 10-10-2007, 01:24 PM   #19
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This is what we offer for big turbo applications. Helps spool up and adds
little torque to bottom end. If something happens, we can offer for example 102.1mm to fix the problem....

Personally I wouldn't go much bigger than 102.5mm

We can custom order headgaskets up to 103mm, no problem.
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