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#1
12-29-2016, 10:16 PM
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Dishing sealed power L2262f
Im looking to knock a half point of compression out of a 400. Its now 10.14:1, according to the math. Iron d-ports.
Can these pistons, L2262f, be dished or worked to get 5cc's out? If yes were is the best place to take it off. If i did the math right that should put me at 9.6 Kevin |
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#2
12-29-2016, 11:06 PM
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Need a machine shop that has a piston vise.Ken(Pontiac dude) did a set for me some years ago.Tom
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#3
12-30-2016, 07:30 AM
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Yes, 5 CCs is nothing to mill out of those as they use the same blank to make 428 piistons with there much bigger dish!
If you motor / block does not have a Intake valve notches I eould strongly concider adding that also , but you would have to do that very careful with the motor assembled. |
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#4
12-30-2016, 10:28 AM
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I want to think HO Racing's old ones had a 0.100x2.8" dish machined in them
__________________
Skip Fix 1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever! 1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand 1965 GTO 4 barrel 3 speed project 2004 GTO Pulse Red stock motor computer tune 13.43@103.4 1964 Impala SS 409/470ci 600 HP stroker project 1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs |
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#5
12-30-2016, 11:40 AM
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Thanx guys. Time to call the local machine shop to see what they can do. Would be nice if they balance there too but i dont think they do.
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#6
12-30-2016, 11:50 AM
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The 4 valve reliefs are already at 6.6cc so adding a certain sized dish might or might not get an additional 5cc.
Ideal would be a mill and a dish the shape of the chamber.
__________________
Skip Fix 1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever! 1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand 1965 GTO 4 barrel 3 speed project 2004 GTO Pulse Red stock motor computer tune 13.43@103.4 1964 Impala SS 409/470ci 600 HP stroker project 1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs |
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#7
12-30-2016, 12:07 PM
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Get some clay and pack it in the 4 valve notches, then cut it off level with a single edge rasor , roll all the clay together then roll it out into a circle as best you can until it's as half thick as the deep side of one of the valve notches.
Now your in the Ball park as to having the depth and area to have a shop machine a dish. |
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#8
12-30-2016, 06:08 PM
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Quote:
You could always machine .024" across the entire piston top and accomplish the same scenario! This would change the C.H. from 1.714" to 1.690" and have no effect on the valve notches. Machining the tops is much easier than machining the dish also. You also have one other option to help, an .051" head gasket in place of an .038" (Fel-Pro), I'm assuming this is what you have now. Gasket alone though won't give you the 5 cc's you need. Thanks, Gary in N.Y. P.S. Wishing all here a Happy New Year! |
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#9
12-30-2016, 06:52 PM
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Quote:
__________________
Skip Fix 1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever! 1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand 1965 GTO 4 barrel 3 speed project 2004 GTO Pulse Red stock motor computer tune 13.43@103.4 1964 Impala SS 409/470ci 600 HP stroker project 1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs |
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#10
12-30-2016, 07:44 PM
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You need to measure the top thickness and keep a minimum of 0.200" to determine the max amount you can mill.
__________________
1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
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#11
12-30-2016, 08:34 PM
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Quote:
Stan
__________________
Stan Weiss/World Wide Enterprises Offering Performance Software Since 1987 http://www.magneticlynx.com/carfor/carfor.htm David Vizard & Stan Weiss' IOP / Flow / Induction Optimization - Cam Selection Software http://www.magneticlynx.com/DV Download FREE 14 Trial IOP / Flow Software http://www.magneticlynx.com/DV/Flow_..._Day_Trial.php Pontiac Pump Gas List http://www.magneticlynx.com/carfor/pont_gas.htm Using PMD Block and Heads List http://www.magneticlynx.com/carfor/pont_pmd.htm |
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#12
12-31-2016, 02:45 AM
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Thanx guys
I found a shop 20 mins away that does meticulous work that didn't sound phased. Said he hasnt done it in awhile but hes sure he has his old fixture laying around, sounded like he chucks the piston in the lathe. And of course he doesn't balance so then it all goes to another shop for that. |
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#13
12-31-2016, 02:56 AM
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Quote:
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#14
12-31-2016, 07:47 AM
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x2 , do the dish milling other wise milling the whole piston top will make the motor more likely to rattle with any given level cranking compression.
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