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Mahle 2618 Gas ported Boost pistons ,-12cc

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Old 03-23-2011, 01:29 AM
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Originally Posted by Blown06
My bad, it would be a 74cc head and I think the new cometics are 4.150 and .051 compressed. I tried a little calculating with those figures and came up with about 8.5:1.

Does that gasket bore size seem too big for a 4" bore?
It's on the big side and adding a cc or two but should seal ok. I would prob go with the LS9 if it were me. Prob too much dish for a 74cc head.
Old 03-24-2011, 11:39 AM
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Price lowered 585.00!
Old 03-25-2011, 12:58 AM
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How much are they new?

Do they come with the pins?
Old 03-25-2011, 09:04 PM
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What do the gas ports do?
Old 03-26-2011, 08:29 PM
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The Whole Noise from piston Slap is mostly Myth
1. I run Wiseco's in all my LS builds at .0035-.004max P-W clearance and have had no noise Except using stock rods and pistons ive heard some pin noise
2. Wiseco Uses Offset Pins to also help against any noise and to lessen the angle slightly, seems small but it helps, My 383 in my truck is Bone quiet No piston Noise at all either is the last diamond piston 383 or 416 i did
People used to Run 2618 pistons at .006-.010 p-w clearance and thats noisey as hell! and thats where the myth started And now piston Manufacturerers are using that myth as a selling point for their product!
Wiseco, Diamnd, and Manley are the only ones i know of that use offset pin locations off the shelf and out of the 3 I've been extremely impressed with Wiseco's Pistons and rings fwiw JMO
Old 03-26-2011, 08:32 PM
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Originally Posted by 1slow01Z71
What do the gas ports do?
They force Combustion Gases behind the Top ring to improve ring seal
Usually via lateral machining near the top ring or Drilled holes in the top of the piston, Usually used for Racing engines Because Cylinder wall life Goes Down and eventually the holes Plug up LOL
Old 03-27-2011, 02:00 AM
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Originally Posted by Blown06
How much are they new?

Do they come with the pins?
Yes pins, and rings. 585 is as low as Im going to go; if they don't sell soon, im going to just run them.

Originally Posted by Pontiac Derek
The Whole Noise from piston Slap is mostly Myth
1. I run Wiseco's in all my LS builds at .0035-.004max P-W clearance and have had no noise Except using stock rods and pistons ive heard some pin noise
2. Wiseco Uses Offset Pins to also help against any noise and to lessen the angle slightly, seems small but it helps, My 383 in my truck is Bone quiet No piston Noise at all either is the last diamond piston 383 or 416 i did
People used to Run 2618 pistons at .006-.010 p-w clearance and thats noisey as hell! and thats where the myth started And now piston Manufacturerers are using that myth as a selling point for their product!
Wiseco, Diamnd, and Manley are the only ones i know of that use offset pin locations off the shelf and out of the 3 I've been extremely impressed with Wiseco's Pistons and rings fwiw JMO
I agree that the wiseco is a nice piston, it's just too heavy, and I don't want offset pins. The offset pin does wonders for noise, but I have found power with on center pistons vs offset. Have you ran the wiseco's with big power FI @.0035''? I'm a fan of tight clearence but anything below .0045" with a boosted 2618 piston and you might get bit.

Originally Posted by Pontiac Derek
They force Combustion Gases behind the Top ring to improve ring seal
Usually via lateral machining near the top ring or Drilled holes in the top of the piston, Usually used for Racing engines Because Cylinder wall life Goes Down and eventually the holes Plug up LOL
This is just like the 2618 .006~.0010''mith. Lateral(side gas ports) don't clog like the top, and running a gas ported piston allows the ring to contain more cyl psi with less tention. It mimmics a high tention ring under power but normal tention when under cruise. I only use 8 gas ports on a street engine vs 10 on a race setup. Have you ever seen a cyl that has ran a hellfire high tention ring on the street? I ran the std low tention Mahle rings/ gas port in my mid 9 sec 370, this setup had zero blowby under boost, and cyl walls look perfict.
Old 03-27-2011, 03:10 AM
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I wasn't asking if you would come off the price, I was just wondering what they cost new with the ring set. I'm sure this is a great deal, I'm just worried I'd have to cut the **** out of my heads to get the compression to work, and then I'm concerned that my block won't clean up with a .005 hone job.

I'm thinking about it.............
Old 03-27-2011, 03:32 AM
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I know I was just stating my price. I paid 540 for them then 125.00 for the gas ports. When the price sheets all catch up to the amendment they will be well over 600.00. I hate to see you hack up your heads for a piston. You should prob go with a -3~5cc flat top.

Last edited by stock48; 03-28-2011 at 03:39 AM.
Old 03-28-2011, 02:00 AM
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Yea.

Free bump.


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