What kind of power gain by going from 9:1 to 10:1 compression?
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What kind of power gain by going from 9:1 to 10:1 compression?
Would there be a noticeable gain? or is it not worth the trouble?
I currently have b20b pistons in my b20vtec motor and I was thinking of just putting in a b20z pistons.
LMK.
Jay Kim
I currently have b20b pistons in my b20vtec motor and I was thinking of just putting in a b20z pistons.
LMK.
Jay Kim
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From: Miami, Fl
Re: What kind of power gain by going from 9:1 to 10:1 compression? (chris@allmotor.net)
I agree with Chris, get better pistons if you are going to go throuth the trouble. Maybe 11:1 if you want to be safe.
Jay
Jay
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thats what I've heard, but then I started to think about it logically.
If you put PR3 pistons in a stock LS block with stock LS head, your compression would jump from 9.2 to 10.8, so if you gain 5% per 1/10th of a point, you could multiply 1.05^16 to figure out your overall gain. That means you'd be making about 218% of the power you were making before, or 283 horsepower on a stock LS with high compression.
Where as if you go with about a 2.5% increase in power per 1/10th of a point, you'll see a total increase of about 148% (even still a lofty gain of course) for a total power of 192 horsepower.
Which seems the more logical of the two? Even the more logical seems high to me
If you put PR3 pistons in a stock LS block with stock LS head, your compression would jump from 9.2 to 10.8, so if you gain 5% per 1/10th of a point, you could multiply 1.05^16 to figure out your overall gain. That means you'd be making about 218% of the power you were making before, or 283 horsepower on a stock LS with high compression.
Where as if you go with about a 2.5% increase in power per 1/10th of a point, you'll see a total increase of about 148% (even still a lofty gain of course) for a total power of 192 horsepower.
Which seems the more logical of the two? Even the more logical seems high to me
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From: St Eustache, QC, Canada
Re: What kind of power gain by going from 9:1 to 10:1 compression? (LSiTurbo)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSiTurbo »</TD></TR><TR><TD CLASS="quote">For every point in compression it is around 5% more power. </TD></TR></TABLE>
Riiigggghhhhttttt
IMO the difference between 9:1 and 10:1 is maybe 5 hp unless you change other things , but on the same engine its barely worth it
If you go for higher comp then go from 9:1 to 11:1 that will give you a little more throttle response
and about 7-10 hp and 4-7 lbs of torque 
The power lies in the induction system.
The shortblock is where you spend $ for reliability
Riiigggghhhhttttt
IMO the difference between 9:1 and 10:1 is maybe 5 hp unless you change other things , but on the same engine its barely worth it
If you go for higher comp then go from 9:1 to 11:1 that will give you a little more throttle response
and about 7-10 hp and 4-7 lbs of torque The power lies in the induction system.
The shortblock is where you spend $ for reliability
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Compression makes huge power, people forget that because Hondas usually come stock with pretty good compression, but compression makes huge power. Look at the torque diesel makes. Thats all compression
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Re: (-KangaRod-)
I had a stock bottom end ls with cams and some other work. It dynoed at 168 @ 128 pulled that motor out and put in a 10.5 bottom end in the car with all the same parts it dynoed at 178 @ 138. with no other changes. Just by changing the compression to 10.5 it made 10 whp and 10 fttq.
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From: Jacksonville, FL, USA
Re: What kind of power gain by going from 9:1 to 10:1 compression? (AllMotorMonster+)
compression is huge, not only in its gains itself but in what it allows you to run for cams, in turn resulting in huge gains.
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Re: What kind of power gain by going from 9:1 to 10:1 compression? (AllMotorMonster+)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AllMotorMonster+ »</TD></TR><TR><TD CLASS="quote">Would there be a noticeable gain? or is it not worth the trouble?
I currently have b20b pistons in my b20vtec motor and I was thinking of just putting in a b20z pistons.
LMK.
Jay Kim</TD></TR></TABLE>
It will be worth it. Going from 9 to 10:1 is worth 7-10hp in my book. Also putting new pistons and rings will give you more power too.
I currently have b20b pistons in my b20vtec motor and I was thinking of just putting in a b20z pistons.
LMK.
Jay Kim</TD></TR></TABLE>
It will be worth it. Going from 9 to 10:1 is worth 7-10hp in my book. Also putting new pistons and rings will give you more power too.
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From: Spokane, WA, USA
Re: What kind of power gain by going from 9:1 to 10:1 compression? (Rocket)
Big 3 just like Basketball
Compression=the center, makes or breaks the team
Cams=Power Forward
Porting=shooting guard
Compression=the center, makes or breaks the team
Cams=Power Forward
Porting=shooting guard
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Re: What kind of power gain by going from 9:1 to 10:1 compression? (gregsr)
compression will only due what the cam will allow... high comp. + lil cam = not much gain, high comp. + big cam = lots of fun (big gains also)
mike
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From: T.O., Canada
Re: (-KangaRod-)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by -KangaRod- »</TD></TR><TR><TD CLASS="quote">thats what I've heard, but then I started to think about it logically.
If you put PR3 pistons in a stock LS block with stock LS head, your compression would jump from 9.2 to 10.8, so if you gain 5% per 1/10th of a point, you could multiply 1.05^16 to figure out your overall gain. That means you'd be making about 218% of the power you were making before, or 283 horsepower on a stock LS with high compression.
Where as if you go with about a 2.5% increase in power per 1/10th of a point, you'll see a total increase of about 148% (even still a lofty gain of course) for a total power of 192 horsepower.
Which seems the more logical of the two? Even the more logical seems high to me</TD></TR></TABLE>
its said that about a 4% increase in power is made when the compression is raised ONE full point e.g. from 9.2/1 to 10.2/1 c.r, not for every 1/10th.
If you put PR3 pistons in a stock LS block with stock LS head, your compression would jump from 9.2 to 10.8, so if you gain 5% per 1/10th of a point, you could multiply 1.05^16 to figure out your overall gain. That means you'd be making about 218% of the power you were making before, or 283 horsepower on a stock LS with high compression.
Where as if you go with about a 2.5% increase in power per 1/10th of a point, you'll see a total increase of about 148% (even still a lofty gain of course) for a total power of 192 horsepower.
Which seems the more logical of the two? Even the more logical seems high to me</TD></TR></TABLE>
its said that about a 4% increase in power is made when the compression is raised ONE full point e.g. from 9.2/1 to 10.2/1 c.r, not for every 1/10th.
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Re: (Ruby Civic)
So is that 5% per full point with everything else stock? So if I raised mine from 9.6 to 12.6 that would go from stock 124ish to..........143? but since I already have a Stage 1 crower, what kind of power would that get me?
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Re: What kind of power gain by going from 9:1 to 10:1 compression? (AllMotorMonster+)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AllMotorMonster+ »</TD></TR><TR><TD CLASS="quote">Would there be a noticeable gain? or is it not worth the trouble?
I currently have b20b pistons in my b20vtec motor and I was thinking of just putting in a b20z pistons.
LMK.
Jay Kim</TD></TR></TABLE>
you'll make more power with the b20z pistons, but you must modify the valve reliefs in order to run big cams. if you don't modify the reliefs, you'll be limited to only being able to use 98 ITR cams. anything else, and you'll have valve to piston contact!
I currently have b20b pistons in my b20vtec motor and I was thinking of just putting in a b20z pistons.
LMK.
Jay Kim</TD></TR></TABLE>
you'll make more power with the b20z pistons, but you must modify the valve reliefs in order to run big cams. if you don't modify the reliefs, you'll be limited to only being able to use 98 ITR cams. anything else, and you'll have valve to piston contact!
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Re: What kind of power gain by going from 9:1 to 10:1 compression? (TEAMGENDAI)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TEAMGENDAI »</TD></TR><TR><TD CLASS="quote">In my opinion you will probably see about 3 horse power and maybe 2 ft lb just my opinion. good luck</TD></TR></TABLE>
And you're basing this opinion on? Just curious as to see how you came up with such an accurate estimate. Personal experience?
Jay Kim
And you're basing this opinion on? Just curious as to see how you came up with such an accurate estimate. Personal experience?
Jay Kim
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From: Alexandria, VA, USA
Re: What kind of power gain by going from 9:1 to 10:1 compression? (AllMotorMonster+)
i really do not agree, since it has been shown in numerous articles that if you increase the other parameters as suggested that you should gain about 5% per point of compression increase