i neep help with my compression ration...

my probleme is...
b20 bore 85mm with 8,5/1compress
supercharger jr with boost upgrade 10 psi
the probleme is my bore and ratio is to big the supercharger boost only at 7 psi...
212whp 164lbs
now i whant to built a b18c
need to know what bore can i go 82mm 83mm 84mm with how much compression ratio 10/1 or 9/1... a tech guy neer by said that with a stock b18c5 at 10 psi made 280whp..and with the same block but piston 9/1 compression did 225 whp :-(

does jr love high compression or should i go like 9/1 better then 10/1..thanks for your help....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civic sc &raquo;</TD></TR><TR><TD CLASS="quote">i neep help with my compression ration...

my probleme is...
b20 bore 85mm with 8,5/1compress
supercharger jr with boost upgrade 10 psi
the probleme is my bore and ratio is to big the supercharger boost only at 7 psi...
212whp 164lbs
now i whant to built a b18c
need to know what bore can i go 82mm 83mm 84mm with how much compression ratio 10/1 or 9/1... a tech guy neer by said that with a stock b18c5 at 10 psi made 280whp..and with the same block but piston 9/1 compression did 225 whp :-(

does jr love high compression or should i go like 9/1 better then 10/1..thanks for your help....
</TD></TR></TABLE>

Ok. First. check spelling before posting. You sound like 2 year old and it is very difficult to understand your message.

2nd . It's not just about better. It's about what it is you're trying to get out of it. Typically stock 81mm bore is fine, but a bit more bore could be used to extract about 20ft/lbs of additional torque w/ a max of 84.5mm. Do not go above that level. To get the most of the deal, bore and stroke work great together, but don't expect to go over 10,000rpms or anything. Responsiveness, stay stock or just over stock. For peak power, bore to about 83mm or 84mm. the piston used will determine what CR it will be for the size needed. Different companies have different applications.

3rd. Contrary to popular belief, for supercharger setups, higher compression is desired because you are relying more on the engine's capability to create power (via a mechanical pulley) than you are from inert exhaust gases that are reused from a turbocharger. This is why many V8s use a supercharger. It takes power away to make more NET horsepower. 10.0:1 is safest for the VTEC motors but can be done up to 11.1 if perfect tuning is used.

 

lots of good infor from the shodan, but with the horrible effeciency of the JR blower there are more important things. You can use a water injection kit to drastically reduce IAT temps and make the supercharger happy to work with high comp.

JR + 11:1 at 10+lb of boost does not in any way compare IAT to an efficient turbo with an efficient intercooler. W/out water injection i would almost say your going to blow you motor for sure. It wont happen right away, but give it some time and that will inaudibly detonate itself to death.

 

is it a street car?? civic sc, you are in laval ca(??), and the shodan is in the midwest... his pump gas is probably better than the so cal 91 octane **** that we are stuck with out here.

i'm with shane on this deal... and i'm doubtful about your "tech guy", how could a point or so of static c.r. make a 55 h.p. difference? not possible.