3.90" heads on a 4.00" bore - inside please
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From: on the dyno tuning in MD
3.90" heads on a 4.00" bore - inside please Anyone using 3.90" heads (LS6/LS1) on a 4.00" bore (6.0L) - did you radius the chambers for the bigger bore? Was it done by hand, or machine?
TECH Senior Member
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you'll need to open the combustion chambers to match the bore. (You can do this either by hand or CNC. Also depending on the port volumes (I/E) you may need to open those up as well for the added cubes.
Chris
Chris
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From: philadelphia
My dads truck has ls1 heads with a 3.90 chamber.on a stock 4.00 bore.
We had it like that for over a year with no problems.He also raced a guy
i work with in 02 ss camaro auto and won by 2-3 truck lentghs
launching in 4wd.My dad has a 99 gmc 4x4 excad w 6.0L. heads, cam,headers,
stall and all boltons.Not bad for a 5200ld truck.
We had it like that for over a year with no problems.He also raced a guy
i work with in 02 ss camaro auto and won by 2-3 truck lentghs
launching in 4wd.My dad has a 99 gmc 4x4 excad w 6.0L. heads, cam,headers,
stall and all boltons.Not bad for a 5200ld truck.
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From: on the dyno tuning in MD
I don't have the money to port the heads right now, so they are going on like they are - except for maybe matching the chambers. My cam grinder knew they were unported when he ground my cam - he took that and the cubes into account, so I should be alright - maybe not optimum, but alright.
I guess I will take them to a local machine shop when I get them off my current motor and see how much to radius them to match the 6.0L head gasket. I hope it isn't too much.
Anyone else have input for me?
I guess I will take them to a local machine shop when I get them off my current motor and see how much to radius them to match the 6.0L head gasket. I hope it isn't too much.
Anyone else have input for me?
