150 cylinder ID
Moving on from the 200 small block thread we have a selection of 150 barrels for a 175 conversion and would like to use the most power one to start with but how can you ID what's what
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Adam_Winstone
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Just about any factory SIII will be a perfectly good starting point as the end result all depends on the work that you do to it. Most factory SIII barrels, incl. 150, will have a number stub off the inlet manifold gasket area, and they should all have the factory original bore tolerance marking on the head gasket face (+ 0 or -), then it follows the identification marking sequence; LI150 (no markings other than the number stub), LI150S (as LI but with notches out of top fin, 180 degrees, side to side), SX/GP150 (have the same markings as LI150S but also have a square cut across the base spigot at 90 degrees to the transfer windows).
The porting of each is different too but all can be modified to do whatever you're looking to do... some taking more work than others.
I'll not go through 175 or 125 markings at the moment (you've not asked and I can't be bothered!), nor non-Innocenti barrels, however, they tend to follow the same identification marking sequence and or fall short of the first identifier (number stub) if non-Innocenti.
Adam
PS - People will always tell you to start with an original 175 barrel, if you can get one, as the transfers are wider through their length, which helps produce better power if inlet and exhaust are modified for performance. Really though, any Innocent III 150 is a perfectly good starting point.
The porting of each is different too but all can be modified to do whatever you're looking to do... some taking more work than others.
I'll not go through 175 or 125 markings at the moment (you've not asked and I can't be bothered!), nor non-Innocenti barrels, however, they tend to follow the same identification marking sequence and or fall short of the first identifier (number stub) if non-Innocenti.
Adam
PS - People will always tell you to start with an original 175 barrel, if you can get one, as the transfers are wider through their length, which helps produce better power if inlet and exhaust are modified for performance. Really though, any Innocent III 150 is a perfectly good starting point.