PSI relitivity to Sleeves & piston compression
11-16-2006, 03:07 PM
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PSI relitivity to Sleeves & piston compression
i have a
b16a block
sleeved
je 8:1 compression pistons
crower h beam rods
i was wondering kind of PSI pressure this block should be able to sustain? the lower compression should make the block have less absoloute pressure in the cylinders making the natural absoloute pressure lower making the block capable of taking more psi.
b16a block
sleeved
je 8:1 compression pistons
crower h beam rods
i was wondering kind of PSI pressure this block should be able to sustain? the lower compression should make the block have less absoloute pressure in the cylinders making the natural absoloute pressure lower making the block capable of taking more psi.
11-16-2006, 03:48 PM
#2
Re: PSI relitivity to Sleeves & piston compression (b18sihatch)
Sleeves dont fail because of PSI.
Sleeves fail from detonation and insane power levels. Based on what stock sleeves have put down, sleeves should be able to handle crazy power levels with the proper tuning.
Sleeves fail from detonation and insane power levels. Based on what stock sleeves have put down, sleeves should be able to handle crazy power levels with the proper tuning.
11-16-2006, 03:51 PM
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Re: PSI relitivity to Sleeves & piston compression (b18sihatch)
basicly what im saying is that when you have a oem sleeved block and drop the compression and run aftermarket pisons and rods the integrity to hold more boost is raised greatly, you can only run up to 300hp with oem components but with aftermarket pistons and rods you can run 400+ and stock sleeves
well what happens when you drop the compression even farther to 8:1 add aftermarket pistons,rods and ductile iron sleeves. the integrity to hold boost should be greatly improved right?
i was wondering what kinda psi levels it would be safe to run my motor at track wise, 25+ psi?
also with the lower cdompression there should be less absoloute pressure in the cylinder sleeves making the sleeves less stressed out than running OEM compression right, so will that too play a factor in the maxinum ammount of psi able to run in this motor?
well what happens when you drop the compression even farther to 8:1 add aftermarket pistons,rods and ductile iron sleeves. the integrity to hold boost should be greatly improved right?
i was wondering what kinda psi levels it would be safe to run my motor at track wise, 25+ psi?
also with the lower cdompression there should be less absoloute pressure in the cylinder sleeves making the sleeves less stressed out than running OEM compression right, so will that too play a factor in the maxinum ammount of psi able to run in this motor?
11-16-2006, 04:54 PM
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That is true. Also, with lower compression, you can run pump gas with higher psi. Ex. you'll have a lesser chance of detonating at 20psi with pump gas on 8:1 than if you had 9:1 .
11-16-2006, 04:57 PM
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Re: (B18 CYA)
thats pretty muc what i thought.
the thing that got me to thinking about this is i was wondering what kinda power my motor would make, and wasnt sure what kjinda power it would make given it has lower compression so its going to be a little later on full boost.
but it will be able to take much more psi.
so its give and take really
the thing that got me to thinking about this is i was wondering what kinda power my motor would make, and wasnt sure what kjinda power it would make given it has lower compression so its going to be a little later on full boost.
but it will be able to take much more psi.
so its give and take really
11-16-2006, 05:01 PM
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Re: (b18sihatch)
boost,sleeves,pistons,rods are are relitive to eachother becuase they all work together (ovbiously)
so a fulley built motor i guess could take any psi pressure level with given proper tuning and supporting turbo application
but just trying to figure out where my block stands, with psi to compression to horsepower
so a fulley built motor i guess could take any psi pressure level with given proper tuning and supporting turbo application
but just trying to figure out where my block stands, with psi to compression to horsepower
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11-16-2006, 07:26 PM
#8
Re: (b18sihatch)
It really comes down to the entire system.
Think of it like a fully worked stereo setup, the weakest link in the system is the limiting factor...
If your amp is solid and your speakers the best on the market, dont go to radio shack and buy the speaker wire
I know Earl claims his shortblocks are good to 700 whp...right? I am sure Earl is a very conservative guy when he puts up those figures.
I saw that Tony1 posted 60 psi on a setup...I'm sure those aren't super special sleeves. Just good tuning...
Think of it like a fully worked stereo setup, the weakest link in the system is the limiting factor...
If your amp is solid and your speakers the best on the market, dont go to radio shack and buy the speaker wire
I know Earl claims his shortblocks are good to 700 whp...right? I am sure Earl is a very conservative guy when he puts up those figures.
I saw that Tony1 posted 60 psi on a setup...I'm sure those aren't super special sleeves. Just good tuning...
11-16-2006, 07:30 PM
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Re: PSI relitivity to Sleeves & piston compression (xenocron)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by xenocron »</TD></TR><TR><TD CLASS="quote">Sleeves dont fail because of PSI.
Sleeves fail from detonation and insane power levels. Based on what stock sleeves have put down, sleeves should be able to handle crazy power levels with the proper tuning.</TD></TR></TABLE>
Um, sleeves do fail because of stress, its just not proportional to intake manifold pressure. If you were to calculate what would cause the failure of sleeves, you would be looking at stress, and the unit of stress is PSI. Detonation causes huge spikes in pressure within the cylinders. This will result in going above the allowable stress the sleeve can tolerate thus causing them to fail. Crazy power = high cylinder pressure. Same thing applies. Detonation just causes really ridiculous spikes in cylinder pressure which even at lower power levels can destroy **** with relative ease.
Sleeves fail from detonation and insane power levels. Based on what stock sleeves have put down, sleeves should be able to handle crazy power levels with the proper tuning.</TD></TR></TABLE>
Um, sleeves do fail because of stress, its just not proportional to intake manifold pressure. If you were to calculate what would cause the failure of sleeves, you would be looking at stress, and the unit of stress is PSI. Detonation causes huge spikes in pressure within the cylinders. This will result in going above the allowable stress the sleeve can tolerate thus causing them to fail. Crazy power = high cylinder pressure. Same thing applies. Detonation just causes really ridiculous spikes in cylinder pressure which even at lower power levels can destroy **** with relative ease.
11-16-2006, 07:37 PM
#10
Re: PSI relitivity to Sleeves & piston compression (nowtype)
yeah, well you read the part where I said 'sleeves dont fail because of PSI?'
I meant boost PSI, maybe I should have clarified...I didnt mean PSI in the cylinder as the combustion event takes place.
I meant boost PSI, maybe I should have clarified...I didnt mean PSI in the cylinder as the combustion event takes place.
11-17-2006, 06:13 AM
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Re: (B18 CYA)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18 CYA »</TD></TR><TR><TD CLASS="quote">That is true. Also, with lower compression, you can run pump gas with higher psi. Ex. you'll have a lesser chance of detonating at 20psi with pump gas on 8:1 than if you had 9:1 .</TD></TR></TABLE>
you'll also be making more power on the 9:1 motor than on the 8:1 motor with the same 20psi of boost on pump gas. you have to take that into consideration also...higher compression motors require LESS boost to make the same power
you'll also be making more power on the 9:1 motor than on the 8:1 motor with the same 20psi of boost on pump gas. you have to take that into consideration also...higher compression motors require LESS boost to make the same power
11-17-2006, 07:31 AM
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Re: (tnt-gsr)
how much psi can i run? i though honda-tech had learned to stop asking that question a long time ago...
listen to xenocron...
if you have a fucked up tune your motor could blow up at 8 psi...
with a good tune, your motor can last at 20psi...
but the PSI itself is not what decides that... with proper tuning, motors still have limits, these limits ARE NOT DETERMINED BY MANIFOLD PSI they are determines by the power levels, cylinder pressure, detonation... **** like that. on high powered motors, the manifold psi is generally higher, that is an afterthough though.
here is some real world examples of how tuning makes all the difference:
http://forums.evans-tuning.com...=4065
http://forums.evans-tuning.com...=4049
listen to xenocron...
if you have a fucked up tune your motor could blow up at 8 psi...
with a good tune, your motor can last at 20psi...
but the PSI itself is not what decides that... with proper tuning, motors still have limits, these limits ARE NOT DETERMINED BY MANIFOLD PSI they are determines by the power levels, cylinder pressure, detonation... **** like that. on high powered motors, the manifold psi is generally higher, that is an afterthough though.
here is some real world examples of how tuning makes all the difference:
http://forums.evans-tuning.com...=4065
http://forums.evans-tuning.com...=4049
11-17-2006, 07:33 AM
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Re: (ndogg)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ndogg »</TD></TR><TR><TD CLASS="quote">how much psi can i run? i though honda-tech had learned to stop asking that question a long time ago...</TD></TR></TABLE>
That and that SSAC is junk.. hahaha you do have to remember that this is HT so that question wont stop
That and that SSAC is junk.. hahaha you do have to remember that this is HT so that question wont stop
11-17-2006, 02:51 PM
#15
Re: PSI relitivity to Sleeves & piston compression (b18sihatch)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18sihatch »</TD></TR><TR><TD CLASS="quote">i was wondering what kinda psi levels it would be safe to run my motor at track wise, 25+ psi?
also with the lower cdompression there should be less absoloute pressure in the cylinder sleeves making the sleeves less stressed out than running OEM compression right, so will that too play a factor in the maxinum ammount of psi able to run in this motor?</TD></TR></TABLE>
Ok, one more time; BOOST PRESSURE HAS NOTHING TO DO WITH ANYTHING!
The mass of the air going in determines what kind of power it will make. The same mass of air can go in at 10 psi or 30 psi and it will make the same power (assuming other potential variables stay constant), same number of oxygen molecules, same mass of fuel, same power.
You are on the right track about lowering the compression, but im sure you don't understand why yet. A big reason you want to lower the motors compression is because when you compress air it heats up. The motor just has to take the heat when it is in the combustion chamber, so you lower that compression and use more of the turbo to compress the air, then the intercooler cools the dense charge back down giving you more air at a lower temp. Less chance of detonation
The lower compression will not change spool up either.
also with the lower cdompression there should be less absoloute pressure in the cylinder sleeves making the sleeves less stressed out than running OEM compression right, so will that too play a factor in the maxinum ammount of psi able to run in this motor?</TD></TR></TABLE>
Ok, one more time; BOOST PRESSURE HAS NOTHING TO DO WITH ANYTHING!
The mass of the air going in determines what kind of power it will make. The same mass of air can go in at 10 psi or 30 psi and it will make the same power (assuming other potential variables stay constant), same number of oxygen molecules, same mass of fuel, same power.
You are on the right track about lowering the compression, but im sure you don't understand why yet. A big reason you want to lower the motors compression is because when you compress air it heats up. The motor just has to take the heat when it is in the combustion chamber, so you lower that compression and use more of the turbo to compress the air, then the intercooler cools the dense charge back down giving you more air at a lower temp. Less chance of detonation
The lower compression will not change spool up either.
11-17-2006, 03:47 PM
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Re: PSI relitivity to Sleeves & piston compression (Bailhatch)
well i understand all that, and i understand alot of the things that were explained.
however the thing i dont get.
is that when you have forged internals in a oem sleeve block, the ammount of psi able to run becomes great thus increasing the ability to make more power with a block.
oem parts are limited to power becuase they arent as good as forged however both motors posses the same sleeves(oem)
my orginal question was when you sleeve a block with ductile iron sleeves. forged pistons and forged rods. the structual integrity of the block should be much greater than OEM correct.
However what i was getting at was the fact that could you put a psi limit on a fulley built block given a perfect turbo kit and perfect tune.
i also understand the whole thing about compression. lower compression = more psi to make the same ammount of power as a higher compression pistoned motor
lower compression pistons make the motor more resistant to detonation than a higher compression turbo motor yada yada
however the thing i dont get.
is that when you have forged internals in a oem sleeve block, the ammount of psi able to run becomes great thus increasing the ability to make more power with a block.
oem parts are limited to power becuase they arent as good as forged however both motors posses the same sleeves(oem)
my orginal question was when you sleeve a block with ductile iron sleeves. forged pistons and forged rods. the structual integrity of the block should be much greater than OEM correct.
However what i was getting at was the fact that could you put a psi limit on a fulley built block given a perfect turbo kit and perfect tune.
i also understand the whole thing about compression. lower compression = more psi to make the same ammount of power as a higher compression pistoned motor
lower compression pistons make the motor more resistant to detonation than a higher compression turbo motor yada yada
11-17-2006, 03:56 PM
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Re: PSI relitivity to Sleeves & piston compression (b18sihatch)
i was told by the rep over at JE that he wouldnt do more then 15 PSI on the SRP pistons i just bought...
So PSI has something to with it.
So PSI has something to with it.
11-17-2006, 04:14 PM
#18
Re: PSI relitivity to Sleeves & piston compression (b18sihatch)
ya um not sure it has been brought up yet... PSI does not ******* matter! The JE rep is wrong. I give up, this thread is a **** show.
11-17-2006, 10:24 PM
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Re: PSI relitivity to Sleeves & piston compression (btech)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by btech »</TD></TR><TR><TD CLASS="quote">if psi doesn't matter, then i dare u to boost 25psi on a stock engine.</TD></TR></TABLE>
stfu
stfu
11-17-2006, 10:28 PM
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Re: PSI relitivity to Sleeves & piston compression (b18sihatch)
you are making reasonable points... but your missing one KEY concept here...
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18sihatch »</TD></TR><TR><TD CLASS="quote">is that when you have forged internals in a oem sleeve block, the ammount of psi able to run becomes great thus increasing the ability to make more power with a block.</TD></TR></TABLE>
when you say the amount of psi increases thus increasing hte ability to make more power... YOU HAVE THAT BACKWARDS
the amount of power it is able to handle increases thus (IN ******* GENERAL) the amount of psi able to run increases.
NOT THE OTHER WAY AROUND.
in the end MANIFOLD PSI DOESN'T MEAN ANYTHING since 15psi on a gt28 and 15psi on a gt42 are so radically different... its about the amount of air flowing and the power being produced.
if you can't understand that, i'm done.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18sihatch »</TD></TR><TR><TD CLASS="quote">is that when you have forged internals in a oem sleeve block, the ammount of psi able to run becomes great thus increasing the ability to make more power with a block.</TD></TR></TABLE>
when you say the amount of psi increases thus increasing hte ability to make more power... YOU HAVE THAT BACKWARDS
the amount of power it is able to handle increases thus (IN ******* GENERAL) the amount of psi able to run increases.
NOT THE OTHER WAY AROUND.
in the end MANIFOLD PSI DOESN'T MEAN ANYTHING since 15psi on a gt28 and 15psi on a gt42 are so radically different... its about the amount of air flowing and the power being produced.
if you can't understand that, i'm done.
11-18-2006, 06:14 AM
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Re: PSI relitivity to Sleeves & piston compression (ndogg)
you got what i was saying. when you have a oem sleeved block, and you put forged internals in it.
the overall integrity of the block changes to handle more power.
when you put sleeved,rods and pistons in a block the overall integriy of that block has to be changed dramaticly.
the only real question im saying is that with dutile iron sleeved and forged internals
the overall integrity of the block changes to handle more power.
when you put sleeved,rods and pistons in a block the overall integriy of that block has to be changed dramaticly.
the only real question im saying is that with dutile iron sleeved and forged internals
11-18-2006, 07:51 AM
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Re: PSI relitivity to Sleeves & piston compression (b18sihatch)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18sihatch »</TD></TR><TR><TD CLASS="quote">
the only real question im saying is that with dutile iron sleeved and forged internals</TD></TR></TABLE>
uh wtf?
this topic is running in circles.. die already
the only real question im saying is that with dutile iron sleeved and forged internals</TD></TR></TABLE>
uh wtf?
this topic is running in circles.. die already
11-18-2006, 08:11 AM
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Re: PSI relitivity to Sleeves & piston compression (shortyz21)
Copy and pasted from another thread I joined. I hope this ends this thread. It's pretty rediculous.
Originally Posted by adseguy
psi is not a direct corrolation to horsepower and more importantly cylinder pressures. To technically answer your question yes you can run 30psi on 10:1 motor. This needs to be a VERY small turbo. The turbine must restrict the exhaust flow so bad that Volumetric efficiency is also very bad. If that small turbo can even make 30psi and hold it (which it shouldn't) and not make the IAT's hotter then the sun then technically as long as your motor isn't making too much torque and the reversion of gases isn't that bad then yes 30psi even 40psi is fine on pump gas.
My point is that psi is not the question here, but torque numbers (which closely corrolate to cylinder pressure given a MBT tune) are.
octane is the resistance to detonation which I believe is ONLY heat and pressure. The heat is from IAT's as well as timing. Pressure is NOT AT ALL...I REPEAT NOT AT ALL due to boost pressures. When the cylinder pressure exceed 2,500psi in a normal combustion what is 40 or 50 lbs of air really matter . I hope that helps and please correct me if I'm wrong about the octane thing...I think I'm right though
My point is that psi is not the question here, but torque numbers (which closely corrolate to cylinder pressure given a MBT tune) are.
octane is the resistance to detonation which I believe is ONLY heat and pressure. The heat is from IAT's as well as timing. Pressure is NOT AT ALL...I REPEAT NOT AT ALL due to boost pressures. When the cylinder pressure exceed 2,500psi in a normal combustion what is 40 or 50 lbs of air really matter . I hope that helps and please correct me if I'm wrong about the octane thing...I think I'm right though
Originally Posted by adseguy
air pressure does have nothing (at least percentage wise) to do with cylinder pressure
I'm not gonnna get in a hissy fit on "look what I said" "Look what you said", but my point was to say that in those cases hence I stated the cold intake temps EXTREMLY small turbine etc. etc. that air pressure IS NOT the concern here. What I tried to do was provide a theoretical case (totally not usable) to prove that boost is not the issue in determining race gas. I don't like how people say xxpsi you should go to race gas because that is the wrong mentality. We've all seen people say don't boost past XXpsi on stock internals when that is wrong.....this is along the same lines
Quote, originally posted by Suprdave »
The Smaller the Turbo, the higher your Intake Temps are, and the more prone you are to detonation at higher Boost.
agree, but only due to intake temps not boost levels. IAT's vary on the turbo and psi (assuming IC is good)
Quote, originally posted by Suprdave »
If that was the case, then why do you reduce your timing as Boost Pressure goes up?
because you make more power, probably a bit higher IAT's, and the burn rate is faster becasue of the denser air. I don't know what you are trying to say with this becasue we know less timing, well tuned, doesn't mean it's making more power.
Quote, originally posted by Suprdave »
The only way to make more power on Pump Gas would be to run a HUGE Turbo at a VERY Low Boost Level. Resticting the Turbine isn't going to help anything...
I can't disagree, but I can't agree with the logic behind it. As long as you are under xxx torque ( I say 300wtrq for me, but everyone is different) then pump gas should suffice given everything else is in check like piston compression and IAT's. Restricing the turbine will hurt V.E. and cause some reversion so less power will be made and also less cylinder pressure. My point again was to say that boost doesn't cause the limit of pump gas.
Quote, originally posted by Suprdave »
By what you were saying, 10:1 with a 57trim .48AR @ 30psi would be fine on pumpgas because the Turbine is so restricted?? Makes no sense at all.
IAT, Torque (Cylinder Pressure), and reading the plugs are how you determine the max horsepower on pumpgas.
That being said, anyone pushing their $5,000 Engine to it's absolute limit on Junk Gas is a ******* idiot. Hence the 400-450whp Recommendation...
I'm not gonnna get in a hissy fit on "look what I said" "Look what you said", but my point was to say that in those cases hence I stated the cold intake temps EXTREMLY small turbine etc. etc. that air pressure IS NOT the concern here. What I tried to do was provide a theoretical case (totally not usable) to prove that boost is not the issue in determining race gas. I don't like how people say xxpsi you should go to race gas because that is the wrong mentality. We've all seen people say don't boost past XXpsi on stock internals when that is wrong.....this is along the same lines
Quote, originally posted by Suprdave »
The Smaller the Turbo, the higher your Intake Temps are, and the more prone you are to detonation at higher Boost.
agree, but only due to intake temps not boost levels. IAT's vary on the turbo and psi (assuming IC is good)
Quote, originally posted by Suprdave »
If that was the case, then why do you reduce your timing as Boost Pressure goes up?
because you make more power, probably a bit higher IAT's, and the burn rate is faster becasue of the denser air. I don't know what you are trying to say with this becasue we know less timing, well tuned, doesn't mean it's making more power.
Quote, originally posted by Suprdave »
The only way to make more power on Pump Gas would be to run a HUGE Turbo at a VERY Low Boost Level. Resticting the Turbine isn't going to help anything...
I can't disagree, but I can't agree with the logic behind it. As long as you are under xxx torque ( I say 300wtrq for me, but everyone is different) then pump gas should suffice given everything else is in check like piston compression and IAT's. Restricing the turbine will hurt V.E. and cause some reversion so less power will be made and also less cylinder pressure. My point again was to say that boost doesn't cause the limit of pump gas.
Quote, originally posted by Suprdave »
By what you were saying, 10:1 with a 57trim .48AR @ 30psi would be fine on pumpgas because the Turbine is so restricted?? Makes no sense at all.
IAT, Torque (Cylinder Pressure), and reading the plugs are how you determine the max horsepower on pumpgas.
That being said, anyone pushing their $5,000 Engine to it's absolute limit on Junk Gas is a ******* idiot. Hence the 400-450whp Recommendation...
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