OS R2102 Gold and Black different
#16
Tech Apprentice
impossible your either talking that for the piston to go up to a certain height and stop so either the piston diameter is too small or too big or its the sleeve pinch causing the piston roelof there is no way from piston to piston of sleeve to sleeve there can be such a measurable difference just cant happen, then what if u say is true think of all the other things that could be wrong such as where the bearings sit the opening could be bigger and the bearing would fit looser or tighter on different blocks, carb openings would be different motor to motor cause if what u say is true then it don't just apply to piston and sleeves every aspect of the motor would be different that is impossible!! no way....
also there is no way they set aside the better ones for the gold head for what reason the gold head is not sold as a better motor or sold as a modified motor it just don't add up.
bottom line some motors are just cut sharper like I said and certain ones get the luck of having the sharper pieces put toghter...
also there is no way they set aside the better ones for the gold head for what reason the gold head is not sold as a better motor or sold as a modified motor it just don't add up.
bottom line some motors are just cut sharper like I said and certain ones get the luck of having the sharper pieces put toghter...
#17
Tech Regular
from what I have heard from the local drivers, the gold head version has a more sensitive carb. Needs more experience to tune.
#18
You do not have an understanding of the basic engineering that is used to manufacture the PS sets. The taper is deliberate due to the temperature gradient from the top of the sleeve to the bottom and it is GROUND into the hard chrome, not cut. The small tolerances required and the process require matching of piston to sleeve and as Roelof says, sometimes the variables just stack up better. Sometimes by accident but usually deliberately. Even the variations from batch to batch in the alloy of the brass base material and piston aluminium has an effect.
#19
Not taking any sides here, I have been modding, lapping and racing engines since the 90s and having won multiple national titles I can tell you that the overall fit of p&l when race ready is absolutely proportionality critical to the engines performance. Now how it gets there is another story. In 98 after the 200mm worlds in Appledorn we were lucky enough to be treated to a tour of the modern Novarossi factory in Italy...an amazing conglomeration of high tech precision machinery which was mind blowing.
Then you get to the assembly line, i still remember the little old lady from the village who's job it was to reach for a piston from 1 barrel and a liner from another barrel put them together, close enough good enough if you catch my drift.
Now back then you guys more than likely wont know this but you could buy from Novarossi, oversized pistons to rematch with your worn liners. I came back with half a dozen pistons from that factory visit which i used for rebuilding many of my engines. Around 2000 you could no longer purchase pistons alone and had to fork out for a piston liner set, making them more money. I soon started Experimenting lapping techniques with brand new engines and P&L sets so that there was a little nip when assembled and engine was ready to race. I have basically fine tuned and semi automated this lapping process over the years still use this technique to this very day and age and time and time again produce the most cracking engines in this country that are race ready requiring zero running in.......so yea the piston liner fit is Absolutely critical to performance.
Then you get to the assembly line, i still remember the little old lady from the village who's job it was to reach for a piston from 1 barrel and a liner from another barrel put them together, close enough good enough if you catch my drift.
Now back then you guys more than likely wont know this but you could buy from Novarossi, oversized pistons to rematch with your worn liners. I came back with half a dozen pistons from that factory visit which i used for rebuilding many of my engines. Around 2000 you could no longer purchase pistons alone and had to fork out for a piston liner set, making them more money. I soon started Experimenting lapping techniques with brand new engines and P&L sets so that there was a little nip when assembled and engine was ready to race. I have basically fine tuned and semi automated this lapping process over the years still use this technique to this very day and age and time and time again produce the most cracking engines in this country that are race ready requiring zero running in.......so yea the piston liner fit is Absolutely critical to performance.