KL_ZE pistons

[VizualXTC]

Where could I get lower compression pistons for the ZE? So that it would be easier to turbocharge it?

[Sonic]

Lower than the ZE? How about KLD/ 03? You want lower yet? You'll have to have them custom made.<P>It would actually be harder to turbo charge it if you changed the pistons because you'd be changing the pistons. Regardless what pistons you have, turboing is turboing. Nothing will make it easier.<P>[ November 25, 2001: Message edited by: Sonic ]<p>[ November 25, 2001: Message edited by: Sonic ]

[OsoSlo z28]

i disagree. the lower comp the better it is for a turbo. if you already have a high compression, it will not be able to handle as much boost.<P>you can probably find some from JE<p>[ November 25, 2001: Message edited by: cre8v mx3 ]

[VizualXTC]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Sonic:<BR><STRONG>Lower than the ZE? How about KLD/ 03? You want lower yet? You'll have to have them custom made.<P>It would actually be harder to turbo charge it if you changed the pistons because you'd be changing the pistons. Regardless what pistons you have, turboing is turboing. Nothing will make it easier.<BR></STRONG><HR></BLOCKQUOTE><P>The KL03 only has 160HP the ZE has 200. A turbo would bring SO much more power to the ZE than to the 03. I just need to lower compression so I could have a bigger PSI.

[Buff1110]

the reason the ze has more hp is because it has higher compression. if u lower it your basically bringing down to the kl03. get the kl03, save yourself a few bucks and turbo that motor. your giving yourself more work by trying to lower the ze's compression<P>Dan

[OsoSlo z28]

i'm not a v6 guy so i don't know much about these two motors, but you would want to compare these motors from a performance aspect. which one has the best valvetrain setup, what about the exhaust and intake manifolds?(but if your going turbo, the ex man doesn't matter), also look at the block integrity. the higer hp motor might be built stronger so you might want to go with that one. just some things to think about.

[Sonic]

You guys are not reading. I know you can run more boost with lower compression. But lower compression does not make putting a turbo kit on easier... He didn't ask how he can rum more boost, he asked if it would be easier. He asked a question, I answered it. <P>You can run around 5psi on a KL_ZE and around 8-9 with a KL_03.<P>And the only pistons you could get that are dished are KL_03 pistons. And if you wanted even lower then you should swap your rods too. You would have to have everything custom made.<p>[ November 26, 2001: Message edited by: Sonic ]

[Sonic]

Ryan, that's not entirly correct. Yes, you can run more PSI with lower compression pistons. But you get more power with sttock KL_03 cams than you do those of the KL_ZE. <P>And for the manifold? If you had low, low compression pistons running alot of boost you'd want to gut the manifold anyway. Find some Millenia heads and a Millenia manifold and gut the heck out of the manifold. Make it a shell. That would give you optimum performance.<P>So if you want to build a nice strong turbo motor the KL_03 is a much better choice to go with.

[VizualXTC]

how I see it, if I have a 160HP motor running turbo I will get about 200 safe HP. If I have a 200HP motor runing boost, I could possible get 230-250 safe HP, maybe even bring the totals to 300+ crank HP. Tell me if I'm wrong in this.

[Sonic]

Ryan, that is DEFINATLY wrong. You can run 8psi on the KL_03/KLD engine. 8psi giving the right varibles can get you 240+ WHEEL horse power. Probably quit a bit more with alot of tuning and a few extra things. You can only run 5psi on the ZE pistons. I'm not sure what kind of power you would get but it's not even worth it unless you have a turbo and all the pieces laying around to build your own.<P>Dave gave me a link once that showed C.R. vs. PSI... I lost that link. He needs to post it. It explains which is better. compression or boost. <P>Lets see. Have a 10.1:1 CR motor and ONLY run 5psi with an expensive turbo kit? Not worth it at all. If you want more power from a ZE then get a 50shot or so. N20 is extremley cheap compared to turbo. Sure you won't have power all the time, but so what. a ZE'd MX-3 will definatly get up and go.<P>Then once you start chaning stuff like pistons you have to change rings, rip apart the ENTIRE motor, replace all gaskets, and yada yada. You can EASILY spend a grand-two grand on gaskets, seals, bolts, hardware, and a couple bolt ons for a ZE. I've got one riped apart now. Cost WAY more than ever expected. It's not even fully rebuilt even. Bottom end is all stock still.<P>Email me or message me if you like.

[codyhoover]

i've seen a supercharger kit for S2000 that pushes 6lbs on stock 11:1 pistons. why couldnt the ZE 10.1:1 handle 7 or 8lbs? i reallize it a different engine completely but compresion is compression. i think the ZE will handle more than 5 lbs

[David Coleman]

Sean Matthews is running upwards of 7psi on his Turbo'd ZE. [img]shrug.gif"%20border="0[/img]<P>Compression -vs- Boost <P>Almost as fast as a supercharger can be bolted on, the question of how much boost can be run is instantly a concern. When building up a motor to be supercharged, you've also got the question of just how much compression to run. Both of these questions relate to essentially the same set of equations. Assuming that all of the other requirements of the motor are satisfied, the compression -vs- boost aspect is not all that difficult. <P>The only way to make more power is to increase cylinder pressure and burn more fuel. The main purpose of the supercharger is to supply the motor with a more dense air charge, which allows for the ability to burn the additional fuel. By adding a supercharger, additional air should no longer be a problem. Ensuring that there will be enough additional fuel to maintain the proper air to fuel ratio will be the key to using the maximum effective compression. <P>All motors have a static compression ratio. This is the amount that the air inside the cylinder is compressed. It is a ratio of the cylinder volume at BDC to the volume at TDC. When a supercharger is added, additional air is forced into the cylinder effectively raising the compression ratio. The result of this is called effective compression. The formula for finding the effective compression is very easy: <P>((boost psi / 14.7) + 1) x motor compression = effective compression. <P>The effective compression allows a supercharged motor to be compared to a normally aspirated motor. For the most part, a supercharged motor with the same effective compression as a (similar) normally aspirated motor with the same static compression should have about the same overall power. <P>This may bring up the question that if the overall power should be about the same, why go with a supercharger? The main advantage of the supercharger is that it allows for a moderate compression level during normal driving while allowing for very high compression levels when needed. Obviously a high compression motor of about 14:1 makes a lot of power, but it would never survive daily driving. A lower compression motor is great for daily driving, but greatly reduces the potential for power. The supercharger allows for higher compression levels than could be used without a supercharger, while still offering the benifits of a standard compression motor. Many street supercharged systems will go beyond 18:1 effective compression under boost. Under race conditions, many supercharged race motors will go well beyond 22:1 effective compression. Both of these levels are far beyond what could be done reliably or cost effectively without a supercharger. <P>This brings us back to the question of just how much boost or compression can be run. Obviously there can't be a simple number that could be used for every application. This is why it's so critical to chose the proper components. It's not necessary to build a low compression motor to use a supercharger, but the correct parts are still necessary. The biggest factors will be in things like head bolts (or preferably studs), gaskets, and the strength of the other engine components. It goes without saying that the incredible power that a supercharger can add, can easily start breaking things. It is very important that as the boost levels rise, the need for a stronger crank, rods, pistons, etc... becomes very critical. Many people forget this as the motor itself is relatively mild, while the supercharger pushes it well beyond the practical limits it was intended for. <P>Now, back to the compression issue. Anyone who has looked into supercharging has heard that you need a low (static) compression motor. This may have been true once upon a time, when roots type (positive displacement) superchargers ruled the land, but it's not so necessary now. The problem with a low compression motor is that it relies heavily on the supercharger for its power. An 8:1 motor is definitely not going to be a power house. Sure, you can throw 18 lbs of boost on it and get some real power, but why? A higher compression motor of 9.5:1 will have much more power without the blower. Then, with less boost you could easily have the same overall power - only it would be much more usable. Both of the motors (8:1 with 18 lbs boost and 9.5:1 with 12 lbs boost) will have almost the same effective compression and about the same overall power. The big difference will be where you see the power, and how much of a demand will be placed on the supercharger. Obviously, the 9.5:1 motor is going to have far greater torque and low end power as the boost is only starting to come in. It is also going to be much easier to find a blower to survive only 12 lbs of boost -vs- one that would have to put out 18 lbs. It is now very easy to see why a higher compression motor with lower boost is becoming so popular. <P>Please understand that when I say higher compression and lower boost, there are limits to each. Going over about 10:1 will make the amount of boost that is usable drop quickly to the point that the supercharger is somewhat wasted. In my opinion, anything less than 8 lbs of boost is a waste of a supercharger. Going over 10:1 will also make daily driving with pump gas much more difficult. In this same way, compression levels much under 9:1 will require substantial boost levels to make massive power gains. This would require boost levels that are very demanding of a supercharger. This is truly unnecessary. This isn't to say that the lower compression / higher boost set-up doesn't have a slightly higher potential for power, because it does. A lower compression motor has the ability to contain more volume. This can be an advantage, but is such a minor one that it's not necessarily worth the effort - unless it's for an all out race motor. Even then there are limits for the same reasons as the street / strip motor. <P>Once again, the compression -vs- boost issue. For a car that will see the streets (actually for most applications), the best thing to do is start with a motor compression that is high enough to make the horsepower you want for normal driving. Don't rely on your supercharger to make all your horsepower. With a good motor compression, add as much boost as is safe for your particular application. Decide on a final effective compression, and work your way back through the formula to find your maximum boost level: ((effective compression / motor compression) - 1) x 14.7 = boost. With the proper fuel system and related engine components, an effective compression of 16:1 to 18:1 should be more than workable. For heavily modified cars, effective compressions over 20:1 should be very carefully considered. Remember, even Indy cars only run about 18 Lbs of boost and reasonable static compression levels. Technology has come a long way and modern day supercharging should take full advantage of this. <P>While these opinions are not exactly the most popular, they are based on facts and real world performance. While there will always be those who continue with tradition and stick with what was done in the past, it is those who reach for something more that are winning races. Often times, some of the best advice can be found from those who have done what you want to do. All too often it is those who know the least that offer the most advice. After having been involved in supercharging for many years, I have heard it all. Most of it was worthless. It was often the least mentioned things and trail and error that have been the most rewarding. Hopefully this information will help to explain some of the often misunderstood aspects of supercharging. <BR>Copyright© 2001, MotorSports Digest

[VizualXTC]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by David Coleman:<BR><STRONG><BR>For a car that will see the streets (actually for most applications), the best thing to do is start with a motor compression that is high enough to make the horsepower you want for normal driving. Don't rely on your supercharger to make all your horsepower.</STRONG><HR></BLOCKQUOTE><P>So, what I get from this, is that if I ran ~7 PSI, I would get a ~15:1 effective compression. See I would rather have a 200 HP engine running 7 PSI than a 160 engine running 10 PSI because I would still get more power with the ZE. I appreciate the advice, but I am still planning on turbocharging the KL_ZE. It may be costly, but then again, this aint a cheap hobby. Thanks for the info Dave

[Sonic]

What do you mean still get the power of the ZE? Is turbo lag your concern....?

[Sonic]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by codyhoover:<BR><STRONG>i've seen a supercharger kit for S2000 that pushes 6lbs on stock 11:1 pistons. why couldnt the ZE 10.1:1 handle 7 or 8lbs? i reallize it a different engine completely but compresion is compression. i think the ZE will handle more than 5 lbs</STRONG><HR></BLOCKQUOTE><P>So just because a Honda can a Mazda can?<BR> <P>Mazda has never really been know to have the best designed engines. The K-series rods and pistons are weak. You can bend the rods with body strength pressure.<P>The problems that happen with K-series engines are they either blow a piston, spin bearing number 6, or a rod bolt breaks causing the rod to break causing the rod to go through the oil pan or block causing the engine to blow up do to no oil.<P>And with more than 5psi on a ZE you'd probably have to change the injectors, I have not done the math on them so don't quote me on that.