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Gen 4 max bore??

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Old 07-27-2011 | 11:16 PM
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Default Gen 4 max bore??

I have seen several opinions on this, with the consensus being sonic the sleeves. Some say they have several gen 5's at .100, and one thread that they had reached a bore of over 4.55. Is that possible with a 454 mag block? How do you get a .250 overbore? I call B.S. I could not find a thread with the gen 4. info that I could believe.
I am reworking a pair and they are already .60 over and may need a bit more. So in my ultimate wisdom, I figured I would pick up some JE or CP blower pistons and a pair of blowers and see what it would do. I also am considering solid lifters. What is a good rule of thumb for adjustment time? Or is it not worth it with a blower set-up?
Thanks in advance for the help
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Old 07-28-2011 | 12:00 AM
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Maximum Cylinder Bore Diameter 4.310 in.
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Old 07-28-2011 | 12:08 AM
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4.55 would have been a 502, not a 454.
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Old 07-28-2011 | 12:43 AM
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Mines at 4.350" or .100" over. Run a forged Lunati 4.25" crank for 505"s. At least 10 years old and have never had an issue. Did have it sonic tested prior to boring. Pistons are availiable up to .125" though I personally have never known anyone to go that far. I was talking to an old timer about it at a machine shop one time and his reply was "damn, you could read a newspaper through those cylinder walls".LMAO
It's a MK lV

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Old 07-28-2011 | 02:26 AM
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The general rule of thumb for a Mk IV 454 is .070 over, or 4.320. Again, as mentioned, have it sonic tested.
Don't bother with the solid. There is no reason for it these days. The hyd. roller stuff has come so far that you can run about any cam you can dream up and not have any problems. The solids are not worth the hassle imo.
Eddie
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Old 07-28-2011 | 09:59 AM
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I have one engine at .070 over and one at .100 over. Supercharged. I am comfortable with this as I run closed cooling so there is no thickness loss over time like many engines see due to seawater.
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Old 07-28-2011 | 10:04 AM
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I know racers that will go .125 over but thats a race car.
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Old 07-28-2011 | 02:37 PM
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Originally Posted by Young Performance
The hyd. roller stuff has come so far that you can run about any cam you can dream up and not have any problems. The solids are not worth the hassle imo.
Eddie
Eddie, Are you saying that you could run the hydraulic rollers on some solid cams nowadays? Cause I would really like to run hydraulic rollers but I do not want to swap out my cams.
Thanks
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Old 07-28-2011 | 04:18 PM
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Originally Posted by Rookie
Eddie, Are you saying that you could run the hydraulic rollers on some solid cams nowadays? Cause I would really like to run hydraulic rollers but I do not want to swap out my cams.
Thanks
I think he's just saying that there's no reason to run solid state cams anymore, given that the new hydrolic roller stuff doesn't "float" and its even more reliable than solid stuff.
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Old 07-28-2011 | 05:01 PM
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Default Bingo

Every question answered! Thats a first. I fell better about maybe taking it to 70 or 100 and being able to run the blowers if I have to. Thanks agian! Now for the cam selection. I will check back when I get those narrowed down. CUDOS guys.
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