Configuring approx. compression ratio with added boost?
 

say you have a 12:1 motor and you want to add 7psi from a JRSC. Being that the JRSC would effectively raise the compression even more, is there are way to determine the approximate compression without an elaborate formula?

Do you think this would be possible on pump gas without the engine detonating its ass off? I've got pretty good control of the ignitionright now with Ectune (running approximately 28* at 7000 rpm) but added boost will definitely throw that off by a long shot.

Re: Configuring approx. compression ratio with added boost?
 

Depending on cams.. I doubt it. Cam duration and overlap has a lot to do with it. What kind of 12:1 build is it?

Re: Configuring approx. compression ratio with added boost?
 

h23vtec
f22 crank (balanced)
Crower 4340 rods (balanced)
wiseco pistons (balanced)

currently using a stock h22a head.

Re: Configuring approx. compression ratio with added boost?
 

i guess its all going to come down to trial and error.

Re: Configuring approx. compression ratio with added boost?
 

I predict 1 trial 1 error.

Re: Configuring approx. compression ratio with added boost?
 

good thing i have a back up block :P

Re: Configuring approx. compression ratio with added boost?
 

I hope you have backup pistons and head too :P

Re: Configuring approx. compression ratio with added boost?
 

Is there a cooler on the JRSC?

Re: Configuring approx. compression ratio with added boost?
 

No

Re: Configuring approx. compression ratio with added boost?
 

i hope you can tune really good 12.1 is alittle high for non intercooled boost with out a great tune

Re: Configuring approx. compression ratio with added boost?
 

I can tell when i know its not going to work. how about that? :6

If this were to happen i think a watercooled "inline" intercooler would help it out with the heat. like this http://www.pwr-performance.com/images/barrel.jpg

Re: Configuring approx. compression ratio with added boost?
 

maybe consider water/meth injection as well, just for added security.

Re: Configuring approx. compression ratio with added boost?
 

how is that going to help....the charger mounts to the head

Re: Configuring approx. compression ratio with added boost?
 

Jg was known for high compression/boosted set ups. They made huge torque #'s on small turbos. They also use to oil down the track alot too.

Re: Configuring approx. compression ratio with added boost?
 

that will probably heat up/restrict the ambient air before it gets heated up some more by the jrsc. water/meth injection is probably your best bet to cool intake temps or just a bad ass tune

Re: Configuring approx. compression ratio with added boost?
 

the tune im not so worried about. I know when its going to work or its not going to work based on what i see with the plugs and the amount of timing i have to pull.

there should be quite a few ways to make this work, like i said, should be just a lot of trial and error until i find the right combination.

thanks for all the comments. Now go ---- yourselves.

Re: Configuring approx. compression ratio with added boost?
 

well like stated earlier one trial can and might be your last error (i.e engine is fucked)

Re: Configuring approx. compression ratio with added boost?
 

thats why you dont mash the throttle on the first trial O0

baby steps my friend.

Re: Configuring approx. compression ratio with added boost?
 

where's the porn damnit????

I think meth/water inj would help ward off detonation....
So much for 30+mpg once ur in constant boost....

Whatever you can do fight detonation will be helpful....hopefully it doesn't become a race gas motor with the charger on it.

How much does boost does the JRSC kit run?? I know they have a 9psi pulley, but i don't even think JR recomends the hi boost pulley on the stock h22.....but ur block should be fine B with whats done to it. :8

Re: Configuring approx. compression ratio with added boost?
 

there is a 6,9, 10 and endyn used to make a 12 lbs pulley. I really dont think it will need race gas just to run 6psi. I'm also hoping that i can do it all on 440cc RDX injectors.

it'll be a fun project if i can find one that needs to be rebuilt for really cheap. I'm not about to spend 1500-2000 on a used on.

Re: Configuring approx. compression ratio with added boost?
 

make your own supercharger setup if you can weld

Re: Configuring approx. compression ratio with added boost?
 

u mean like centrifugal?

Re: Configuring approx. compression ratio with added boost?
 

well you can do centrifugal or roots type just centrifugal is easier. i believe there is a guy on here running a supercharger from some toyota on his civic which has a clutch like an a/c compressor hooked up to a switch so the supercharger only is foring air when he wants it to so he can still get good gass milage. search for supercharger. i will try to look but i cant promise ill find it again

Re: Configuring approx. compression ratio with added boost?
 

thanks for the link man. I'm going to look into that and see if i can figure out a way for it to work in my bay. If i went centrifugal tho, i would prolly look into a procharger.

Re: Configuring approx. compression ratio with added boost?
 

votec makes nice centrifical s/c you can probably find those cheaper.

Re: Configuring approx. compression ratio with added boost?
 

Rotrex or bust.

Re: Configuring approx. compression ratio with added boost?
 

damn i completely forgot about that one!