Compression ratio happiness
#12
Compression ratio happiness
If you guy's may have read some of my previous posts the Compression ratio is off on most of these pistons. The Samcoe 12:5:1 piston is actually more like an 11:1 piston and So on and so on. With maybe the exception of Mr. Horsepower, no one has actually CC'ed the these motor's with the new piston. Turn's out with the a 12:5:1 compression piston you have to deck your head .030 do get it at an actuall 12:5:1 ratio. All this info was provided thru COpe Racing out of Florida, they are the Shiznit like Vance & Hines in Motorcycle engines. They did some work to Big Baja's bike and this is what they found on his setup. I always wondered why I could always get away with running 101 octane with out worrying about it.
#13
#14
Compression ratio happiness
I am not exactly sure about the Ron Woods stock bore piston or TVI's but I know at least with Samcoes's piston you probably could. I ran 101 in my stock bore with a 12:5:1 TVI piston and according to Dcryder he said there were some small pits in the intake side probably from Detonation. If that is the case than I would say that TVI has the closer to true Compression numbers. And you wouldn't want to run lower than 100 octane with that one. If you could afford it that VP Ultimate 4 would be good all the way up to 12:1 ratio. I think we should get some more input from RWR ANd TVI and find out if they CC'ed there engines with these new pistons, because I know Samcoe hasn't.
#16
Compression ratio happiness
Originally posted by: ThePunisher
I am not exactly sure about the Ron Woods stock bore piston or TVI's but I know at least with Samcoes's piston you probably could. I ran 101 in my stock bore with a 12:5:1 TVI piston and according to Dcryder he said there were some small pits in the intake side probably from Detonation. If that is the case than I would say that TVI has the closer to true Compression numbers. And you wouldn't want to run lower than 100 octane with that one. If you could afford it that VP Ultimate 4 would be good all the way up to 12:1 ratio. I think we should get some more input from RWR ANd TVI and find out if they CC'ed there engines with these new pistons, because I know Samcoe hasn't.
I am not exactly sure about the Ron Woods stock bore piston or TVI's but I know at least with Samcoes's piston you probably could. I ran 101 in my stock bore with a 12:5:1 TVI piston and according to Dcryder he said there were some small pits in the intake side probably from Detonation. If that is the case than I would say that TVI has the closer to true Compression numbers. And you wouldn't want to run lower than 100 octane with that one. If you could afford it that VP Ultimate 4 would be good all the way up to 12:1 ratio. I think we should get some more input from RWR ANd TVI and find out if they CC'ed there engines with these new pistons, because I know Samcoe hasn't.
#18
#19
Compression ratio happiness
I checked a 12.5 piston today and it had 5cc of positive dome and pin heighth would set it at zero deck. After doing the math this comes to a grand total of 10.1:1 actual compression ratio with a stock unaltered cylinder head.
I think compression ratio should be given using the cc's of a stock unaltered head with stock valves at factory seat heighth. Anything other than that would be speculation.
MrHorsepower
I think compression ratio should be given using the cc's of a stock unaltered head with stock valves at factory seat heighth. Anything other than that would be speculation.
MrHorsepower