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290 pistons

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carnuck View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote carnuck Quote  Post ReplyReply Direct Link To This Post Posted: Oct/03/2011 at 12:01am
Wonder if the 4.0L pistons would work in a 290 build? I have a couple dead 4.0Ls ('91 and '93) I can steal the old pistons from. Hammer Head
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Class Guy View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Class Guy Quote  Post ReplyReply Direct Link To This Post Posted: Oct/03/2011 at 10:32am
Four issues:
 
1) The compression distance of the 4.0 pistons is the same as 2-bbl 290 pistons, which will put the piston about .050"-.060" in the hole and not be good for compression.
2) The dish in the 4.0 pistons is around 12 cc which is much more than stock pistons.  Again, not good for compression.
3) Valve relief pockets will have to be machined into the pistons.
4) You will have to bore the 290 block .125".  Be sure to sonic check the block first.  I have not seen a 290 block that could not be bored that much, but I have only checked 6.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote carnuck Quote  Post ReplyReply Direct Link To This Post Posted: Oct/03/2011 at 10:42am
I guess I'll save those for when I do the 304 then.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote amx007 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/08/2018 at 8:16pm
I’d like to know a price for a set 30 over ty 290 
dream red white and blue
1968 Chicago auto show amx 290 4 speed
1969 driver Amx 290 auto
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: Dec/09/2018 at 6:04am
Egge has them, $444 set:
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mixed up View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote mixed up Quote  Post ReplyReply Direct Link To This Post Posted: Dec/09/2018 at 10:31pm
reading this post don't under estimate the performance of the 290 with alittle work they run and hold up very well my 290 in my rambler is a .030 over 10.5.1 forged piston balanced  torqer intake 750 carb 540 lift 304 duration  very street able 410 gear in the rear 4sp run 12.30 in a 1/4 6000 launch comes thru the trap at 5500  I say not bad for a small cubic inch motor and yes it will put a hurt on a small block chevy or ford  there is no valve work or porting done on he heads that this years project  this motor surprised me on it performace  
69 amx 290 auto
65 220 290 4spd
80 ford fairmont
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Post Options Post Options   Thanks (0) Thanks(0)   Quote farna Quote  Post ReplyReply Direct Link To This Post Posted: Dec/10/2018 at 5:55am
258 pistons should work, it has the same bore as the 290 (3.75"). Not sure about compression height and dish though, could be the same issues as the 4.0L -- a little lower compression when used in a 290.
Frank Swygert
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nextofkin Quote  Post ReplyReply Direct Link To This Post Posted: Dec/10/2018 at 7:17am
mixed up show your build and work on the heads when you do it
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