Can a supercharged KLZE handle a small shot of nitrus?

pelado · Post by **pelado** » October 20th, 2002, 4:12 pm

<BLOCKQUOTE>quote:<HR>Originally posted by ProtegeSTS: Jeff, say you had a properly sized roots blower on your car. What do you think the powercurve would look like? I'd wager it would get more power through a signifigant potion of the powerband.<HR></BLOCKQUOTE>Yeah, kind of like Jeff Abram's Vortech SC dyno plot posted above.

:p[ October 21, 2002: Message edited by: pelado ]

mazdamaniac · Post by **mazdamaniac** » October 20th, 2002, 5:05 pm

<BLOCKQUOTE>quote:<HR>Originally posted by ProtegeSTS: Jeff, say you had a properly sized roots blower on your car. What do you think the powercurve would look like? I'd wager it would get more power through a signifigant potion of the powerband.<HR></BLOCKQUOTE>Uh, a "properly sized" roots-type would have a curve just like mine only with the torque decreasing after the peak at 4k RPM. Have you actually looked at my dyno plot?

I'm making over 180 ft/lbs of torque before 3500 RPM! Would a "properly sized" roots-type do better? Not if you still wanted the thing to be breathing over 6000 RPM... Also, there isn't really much to do to get a "properly sized" roots-type - there are only two sizes that apply. The centrifugal has WAY more options for sizing.That said, I am in the middle of installing a T3/T04 turbo in the car at this very moment...<A HREF="http://www.mazdamaniac.com/turbo/turbo.htm" TARGET=_blank>some pictures of the install</A>[ October 20, 2002: Message edited by: mazdamaniac ]

ProtegeSTS · Post by **ProtegeSTS** » October 20th, 2002, 6:54 pm

<BLOCKQUOTE>quote:<HR>Originally posted by mazdamaniac: Would a "properly sized" roots-type do better? Not if you still wanted the thing to be breathing over 6000 RPM... <HR></BLOCKQUOTE>Hmm, yeah, I have looked at your dyno... And you know what I see? Your curve sure seems to FALL FLAT ON ITS FACE at 5700 rpm.So what does that tell me?a) You and Darin both have compressors that are too small to keep the powercurve rising out to redline. Hence why you make so much power at low rpmb) Youre supercharged engine at 11 psi wasnt nearly as powerful as Darin's turbocharged motor at 8psi. And that was even at low rpm, say like 3000rpm, where he had over 200 lb-ft and you were still down around 175 lb-ft.

mazdamaniac · Post by **mazdamaniac** » October 20th, 2002, 11:49 pm

<BLOCKQUOTE>quote:<HR>Originally posted by ProtegeSTS: Hmm, yeah, I have looked at your dyno... And you know what I see? Your curve sure seems to FALL FLAT ON ITS FACE at 5700 rpm.So what does that tell me? <HR></BLOCKQUOTE>The only thing that should "tell" you is that something happened at that air flow rate. What "happened" is the engine ran out of fuel. That dyno was performed at 9 psi and before I got the extra injector setup installed on the car. If the centrifugal really ran out of breath (which they simply don't do; that isn't how they work and you should know that before you stick your foot in your mouth again), the curve would start to drop at that RPM, not hold steady like it did. A centrifugal will continue to make more and more boost as the RPM rises until it falls apart. Air was not the problem. Fuel was.

ProtegeSTS · Post by **ProtegeSTS** » October 21st, 2002, 2:46 am

<BLOCKQUOTE>quote:<HR>Originally posted by mazdamaniac: The only thing that should "tell" you is that something happened at that air flow rate. What "happened" is the engine ran out of fuel. That dyno was performed at 9 psi and before I got the extra injector setup installed on the car. If the centrifugal really ran out of breath (which they simply don't do; that isn't how they work and you should know that before you stick your foot in your mouth again), the curve would start to drop at that RPM, not hold steady like it did. A centrifugal will continue to make more and more boost as the RPM rises until it falls apart. Air was not the problem. Fuel was.<HR></BLOCKQUOTE> But boost is not imporant, mass flow is. Theoretically, if the compressor housing and wheel are too small, it will eventually just becaome a heat pump, and be so inefficient that more boost wont mean more air. Once thats the case, the dyno will look a lot like yours, or Darin's for that matter.Why wont you accept that a Roots blower would have given you more power at a lower rpm? and wouldnt have been as peaky as your motor?Centrifugal supercharger will give boost relative to RPM. A roots blower will give the same amount of boost no matter where you are in the rpm band. True, its less efficient overall, but if your Centrifugal is only pushing 3psi of boost, even an unefficient roots blower at 8psi will give more power.

mazdamaniac · Post by **mazdamaniac** » October 21st, 2002, 3:29 am

<BLOCKQUOTE>quote:<HR>Originally posted by ProtegeSTS: Why wont you accept that a Roots blower would have given you more power at a lower rpm? and wouldnt have been as peaky as your motor?<HR></BLOCKQUOTE>Why don't you accept that you keep changing your argument each time I answer you?A roots blower could be sized to produce more boost at a lower RPM than the centrifugal. The consequence of that would be the blower would be over-spun by the time the engine reached the end of the desired RPM range and would thereofore be unusable. If the roots type is setup for the correct RPM range the blower would be out of air before the end of the RPM range with only a minor increase of available air at the low RPM range over the flow of the Vortech. <BLOCKQUOTE>quote:<HR> Centrifugal supercharger will give boost relative to RPM. A roots blower will give the same amount of boost no matter where you are in the rpm band. <HR></BLOCKQUOTE>What you mean, I suppose, is that the roots will displace the same amount of air volume per revolution, regardless or RPM while the centrifugal will produce a flow that is a function of the square of the RPM. And? [img]shrug.gif"%20border="0[/img] <BLOCKQUOTE>quote:<HR>True, its less efficient overall, but if your Centrifugal is only pushing 3psi of boost, even an unefficient roots blower at 8psi will give more power.<HR></BLOCKQUOTE>You can't just ignore one aspect of the performance constraints of a system for another. The "less efficient overall" part is crucial, but even the remainder of that statement is just in left field. A roots type that is set up to deliver 8 psi peak might deliver an extra PSI at 2000 RPM over the centrifugal setup for the same but it will very quickly find itself in adiabatic hell before it reaches the end of the useable RPM band. Which means your "mass flow" that you allude to goes right out the intercooler. Anyway, I thought you said that the centrifugal was "too much, too soon"? Why are you now arguing that the roots blower would get that power out even earlier?

ProtegeSTS · Post by **ProtegeSTS** » October 21st, 2002, 10:48 am

<BLOCKQUOTE>quote:<HR>Originally posted by mazdamaniac: A roots blower could be sized to produce more boost at a lower RPM than the centrifugal. The consequence of that would be the blower would be over-spun by the time the engine reached the end of the desired RPM range and would thereofore be unusable. If the roots type is setup for the correct RPM range the blower would be out of air before the end of the RPM range with only a minor increase of available air at the low RPM range over the flow of the Vortech.<HR></BLOCKQUOTE>It seems as though you have little understanding of how postitive displacement blowers work. First off all, they deliver FULL boost right off idle. Like 1100 rpm, they'll be at 8psi, or whatever you've geared it to run. And being that they move the same amount of air (other than through efficiency differences) per revolution, they deliver FULL BOOST at redline. They shouldn't overspin themselves. If they do, you've chosen the wrong blower for your application. This "minor increase of available air" that you speak of is totally false. At low rpm, you have the FULL 8 lbs of boost. <BLOCKQUOTE>quote:<HR>What you mean, I suppose, is that the roots will displace the same amount of air volume per revolution, regardless or RPM while the centrifugal will produce a flow that is a function of the square of the RPM. And? [img]shrug.gif"%20border="0[/img]<HR></BLOCKQUOTE>AND this means that your powercurve will be far "peakier" than the same engine with a roots blower. If the amount of boost remains constant, then a dyno graph of the roots engine will look just like the oem curve, but with more power. A centrifugal supercharged engine will become very peaky. Peaky is not good in my opinion, as its not as useable. <BLOCKQUOTE>quote:<HR>You can't just ignore one aspect of the performance constraints of a system for another. The "less efficient overall" part is crucial, but even the remainder of that statement is just in left field. A roots type that is set up to deliver 8 psi peak might deliver an extra PSI at 2000 RPM over the centrifugal setup for the same but it will very quickly find itself in adiabatic hell before it reaches the end of the useable RPM band. Which means your "mass flow" that you allude to goes right out the intercooler. Anyway, I thought you said that the centrifugal was "too much, too soon"? Why are you now arguing that the roots blower would get that power out even earlier?<HR></BLOCKQUOTE>Yes, efficiency is cruical, and Ill deal with that a bit later. However, again you prove that you dont understand how a roots blower works. At 2000rpm, the engine will have FULL boost, not "might deliver an extra psi". No, that's not how it works. Once you get up towards redline, when the adiabatic efficiency is starting to take its toll on mass flow, this is where the Centrifugal supercharger will always outpower the roots. But my contention IS and has always been that the overall powerband of the roots blower is far more useful than the sharp increase in power for the last 1500 rpm that a Centrifugual will really overpower a roots."too much, too soon" spoke to the SHAPE of your curve. With SHAPE, I mean the slope of the torque curve. Yours is too steep, in my opinion. Even with great throttle control, that car is going to be hard to drive at 10/10ths. A roots blower, since it just enhances the stock torque curve, is FAR easier to drive like you mentioned, by just using a sensitive right foot.Ok, now as far as efficiency goes with a roots, here is a dyno graph that illustrates my point exactly.<A HREF="http://www.protegeclub.com/forum/attach ... tid=129812" TARGET=_blank>dyno</A>"The purple diagonal line is the Vortech HP, the purple horizontal line is the Vortech torque curve, the green shade is the JRSC hp at 6 psi, the light pink shade is the JRSC torque at 6 psi, the dark pink shade is the JRSC at 8 psi, and the blue shade is the JRSC torque at 8 psi."If you take a good look, the Vortech will outpower the roots at 6 psi ONLY AFTER 6000 RPM. That's right kids, it has a 2000 rpm range and the real impressive peak number, 218 hp, doesn't come until just about 7900 RPM, right when you shift. At every point from 2000 RPM to 6000 RPM, the 6 psi roots will make more power than the Vortech supercharger.

mazdamaniac · Post by **mazdamaniac** » October 21st, 2002, 1:40 pm

OK. I don't have time to continue this in this fashion. When you get your facts straight, I'll be more inclined to discuss the issue, but your information is so off it is practically alien. There is NO blower configuration I have ever seen that supplies full boost at 2000 RPM and is still functional at redline or anywhere near it. It just won't happen. Even if you could invent a variable-gain system to change the ratio and flow rate to match the VE of the engine at every RPM, you still couldn't address the adiabatic issue in the same way. You would need a blower that is made out of the same stuff as the 2nd Terminator. I have a lot of direct experience in this. I have installed roots-type blowers on several Miatas, a GSR-motored Integra, a BMW and two '70 hemi 'Cudas. I have installed centrifugal blowers on two Mustangs and a Camaro besides my MX-3. I have a VATN turbo on my Miata and have installled traditional turbo systems on several Civics and a 2nd gen Eclipse. Beyond that, I work with two shops in my area that tune and install stuff like this (Tint Shop in Rockville and Altered Atmospheres in Gaithersburg), so I see countless aftermarket systems go by, good and bad. Your data just isn't even realistic, though it is imaginative.

Turboge · Post by **Turboge** » October 21st, 2002, 2:12 pm

<BLOCKQUOTE>quote:<HR>There is NO blower configuration I have ever seen that supplies full boost at 2000 RPM and is still functional at redline or anywhere near it. It just won't happen. Even if you could invent a variable-gain system to change the ratio and flow rate to match the VE of the engine at every RPM, you still couldn't address the adiabatic issue in the same way. You would need a blower that is made out of the same stuff as the 2nd Terminator. I have a lot of direct experience in this. I have installed roots-type blowers on several Miatas, a GSR-motored Integra, a BMW and two '70 hemi 'Cudas.<HR></BLOCKQUOTE>I beg to differ. At the current time I cannot provide to you the dyno sheet but it is going to be accesible if you need the proof.The company which does my fabrication has used an Auto-rotor twin-screw supercharger installed on a 1.8 Miata made power from ~1500-7600... I'm not really sure what you mean by a blower that won't make power from 2000-redline... Unless you make the redline 9000. Blower inneficiency will kick in eventually but that is why we size the supercharger for the application. It sounds like you may be using the wrong blower for the application.

big mike · Post by **big mike** » October 21st, 2002, 2:46 pm

<BLOCKQUOTE>quote:<HR>Originally posted by mazdamaniac: OK. I don't have time to continue this in this fashion. When you get your facts straight, I'll be more inclined to discuss the issue, but your information is so off it is practically alien. There is NO blower configuration I have ever seen that supplies full boost at 2000 RPM and is still functional at redline or anywhere near it. It just won't happen. Even if you could invent a variable-gain system to change the ratio and flow rate to match the VE of the engine at every RPM, you still couldn't address the adiabatic issue in the same way. You would need a blower that is made out of the same stuff as the 2nd Terminator. I have a lot of direct experience in this. I have installed roots-type blowers on several Miatas, a GSR-motored Integra, a BMW and two '70 hemi 'Cudas. I have installed centrifugal blowers on two Mustangs and a Camaro besides my MX-3. I have a VATN turbo on my Miata and have installled traditional turbo systems on several Civics and a 2nd gen Eclipse. Beyond that, I work with two shops in my area that tune and install stuff like this (Tint Shop in Rockville and Altered Atmospheres in Gaithersburg), so I see countless aftermarket systems go by, good and bad. Your data just isn't even realistic, though it is imaginative.<HR></BLOCKQUOTE>If you don't believe there's a forced induction system that can do it, obviously you never drove your customer's GSR with the Jackson. Jackson'd cars always hit full boost nearly instantly due to their relatively small size and the very nature of the design of a positive displacement supercharger. Jackson's will make boost at IDLE if the bypass valve isnt functional. Centrifugal superchargers only advantage is on large displacement poor air flowing cars that need more top end oomph, they're a terrible choice for most street imports unless your primary goal is a mean dragster with a very short spurt of top end power. I dislike roots chargers due to their very low efficiency and high levels of heat, but they're excellent for a street/auto-x car that needs more oomph all the time to scurry around. I really think Jesse's dyno chart from jackson speaks for itself, you can see the difference right there, the jackson car is making all KINDS of boost at 2000 rpm vs the vortec. If your gonna waste the time on induction, I'd roll on turbo power any day, they're far more adaptable and efficient than any belt driven SC solution ever could hope to be. As for a small roots charger going adiabatic, my friend Greg is running a 9 psi pulley on a JRSC and gets instant boost <you touch the gas, the boost gauge crosses 0 vac instantly> and it runs all the way out to redline full pull without any problems. Roots blowers by nature have a linear CFM delivery that when sized properly allows them to feed the engine a virtually perfectly flat boost in CFM all the way up to give it a nice smooth, but elevated torque curve. If you use too small of a pulley you can overspeed the compressor and heat the intake charge massively, and damage the compressor, but they're capable of a very wide range of rotational speeds before they go adiabatic. To further clarify the issue, you realize without a bypass system a twin screw supercharger will cause a car not to run at all? If the screws arent turning there is no way for air to get past them, they physically move the air from one side of the assembly to the other, and they do it faster than engine vacuum is capable of.Anyways, if you think I just stepped off the n00b boat and don't know what I'm talking about, you can look me up in the Escort and Protege world, I'm pretty sure you'll find I'm a highly respected source of information for all those guys.[ October 21, 2002: Message edited by: big mike ]

ProtegeSTS · Post by **ProtegeSTS** » October 21st, 2002, 3:02 pm

<BLOCKQUOTE>quote:<HR>Originally posted by mazdamaniac: OK. I don't have time to continue this in this fashion.Your data just isn't even realistic, though it is imaginative.<HR></BLOCKQUOTE> Yes, dyno data is quite imaginative. Especially when you dont have any to the contrary.Maybe when you find some DATA to actually back up your claims, you can post that. That would be helpful. Until then, I have data and people here who've OWNED roots blower powered cars who say youre wrong.Im done for now.

pelado · Post by **pelado** » October 21st, 2002, 9:47 pm

Holy s---, Batman!I hadn't visited this thread in a few days, wow!! I don't like getting in the midst of an argument but I also don't like what I read here.Jesse, you change your complaints about the Vortech like an incumbent politician up for re-election.First it was no power down low, then it's too much power down low, no, it's the shape of the curve......You have way too much ego and not enough class. You didn't give Abrams credit for taking a POS TKT kit and making it work, even if it doesn't work exactly like YOU would want it to. To argue effectively, you need to acknowledge experience. After all, where's YOUR website with YOUR roots blower install?Another thing, everybody has to get all their facts exactly right with you the first time. So what if one fact is not 100% correct? To you, they know nothing.Frank Lloyd Wright was an arrogant bastard who often treated his peers as if they knew nothing. He could get away with this because he was, after all, a genius.Jesse, you're not a genius.

ProtegeSTS · Post by **ProtegeSTS** » October 21st, 2002, 11:24 pm

you've misinterpeted what I said. I NEVER changed my arguemnt. I kept trying to change how I worded it so MAYBE one of you would understand it. It didnt seem to work.I acknoledge that Jeff did something that NOBODY else had ever done, and through a lot of time and effort, got it to actually work pretty well.My arguement stems from the opinion that Centrifugual superchargers are a poor choice for a motor such as a KLDE or ZE due to their peaky nature.Shape of the curve, and not enough power down low are RELATED. I NEVER said anything about too much power down low. The "too much too soon" was related to how when the compressor DID start making meaningful boost, the torque curve's slope was so drastic that it would be VERY hard to control as a driver.I was upset that Jeff decided to insult me, when his info was wrong. Such as: "When you get your facts straight, I'll be more inclined to discuss the issue, but your information is so off it is practically alien."AND "Your data just isn't even realistic, though it is imaginative." I took offense to that. Sorry, i shouldnt have, as this is just a message board. But with as respected as Jeff is in the MX-3 community, and how he went off spouting off all his expirience, I was suprised to see that his info was still WRONG. I corrected it.Jeez, im sorry you dont like the way I explained my side. But damn, why must you bite my head off because I proved my point? What did I do to you?[ October 21, 2002: Message edited by: ProtegeSTS ]

mazdamaniac · Post by **mazdamaniac** » October 22nd, 2002, 3:52 pm

<BLOCKQUOTE>quote:<HR>Originally posted by ProtegeSTS:<HR></BLOCKQUOTE> <BLOCKQUOTE>quote:<HR>The size of a Centrifugal supercharger has ZERO to do with how soon it starts to give meaningful amounts of power increase.<HR></BLOCKQUOTE> <BLOCKQUOTE>quote:<HR>Roots blower: full boost everywhere, and a flat torque curve<HR></BLOCKQUOTE> <BLOCKQUOTE>quote:<HR>Turbo: most power, but at cost for turbo lag<HR></BLOCKQUOTE> <BLOCKQUOTE>quote:<HR>peak numbers and times dont really mean much, because nobody has done a good roots blower setup, or a turbo.<HR></BLOCKQUOTE> <BLOCKQUOTE>quote:<HR>Centrifugal supercharger will give boost relative to RPM. A roots blower will give the same amount of boost no matter where you are in the rpm band.<HR></BLOCKQUOTE>Not a single one of those statements is based in reality.Then you said this: <BLOCKQUOTE>quote:<HR>There's his dyno... and its exactly what i dont like. He's gaining 100 hp from 3000 rpm to 5000 rpm. Thats too much, too fast, IMHO. A roots blower would be better, again in MY opinion as far as driveability....its just less peaky, at the cost of some top-end efficiency.<HR></BLOCKQUOTE>So, you want MORE power than the centrifugal delivers EVERYWHERE in the power band so that there is no increase in power from one RPM range to another? In other words, you want the HP curve to look like the torque curve? Hmm. That's a realistic goal. I guess if you had a constant velocity transmission you could approximate that effect. <BLOCKQUOTE>quote:<HR>Why wont you accept that a Roots blower would have given you more power at a lower rpm? and wouldnt have been as peaky as your motor?<HR></BLOCKQUOTE> Because it wont and it wouldn't. I'm not saying that my results are typical, but my dyno bears out what the facts hold. The problem, simply put, is you are equating one measurement with another as well as one physical phenomenon with another. Power and boost are not the same thing. Time and RPM are not the same thing.Plus, your argument is that my power curve is "peaky", but as you can see my torque curve is completely flat and my horsepower curve is completely linear. You cant show my dyno as a support for your argument because, no matter how many times you reiterate, restate or reconfigure your argument, my plot will not fit your imaginary data.I have an idea. Read "Maximum Boost" and "Supercharged" by Corky Bell and give us a call back later.[ October 22, 2002: Message edited by: mazdamaniac ]

ProtegeSTS · Post by **ProtegeSTS** » October 22nd, 2002, 7:00 pm

Since you started reading off your favorite titles, here's one, From the "Do-It-Yourself Guide to Street Supercharging" by Pat Gandahl. (Pages 76-77) ____________________________________________ The major problem is that not only is the centrifugal blower not a positive displacement pump, but that the kinetic energy imparted to the air molecules by the spinning impeller increases roughly as the square of the tip speed of the blades. This might sound like another asset at first - if you get 10 pounds of boost at a given blower RPM, doubling the blower speed will give you four times as much boost, and tripling the blower RPM will give you nine times more boost. But think of it in reverse. Your engine can only handle a given amount of boost on the street; therefore the maximum boost level is set. Let's say you want ten pounds of boost at 6,000 engine RPM, and you gear the blower accordingly. No problem. But, at 3,000 engine RPM, the blower speed will be cut in half (since the blower is geared in direct proportion to the crank regardless of the overdrive ratio), and the boost level will be reduced by four times, to only 2-1/2 pounds. If the centrifugal blower makes 7 pounds boost at 6,000 RPM (which is typical for a street set-up), it will only make 1.75 pounds at 3,000 RPM. Thus the centrifugal blower is very "peaky", or speed sensitive. It will give good, efficient boost at higher RPM, but very little boost or torque at lower engine speeds. As a result, a centrifugal blower is excellent for top-end speed contests, such as Bonneville, or sustained high-RPM racing such as on a long oval track (i.e., Indianapolis). But the centrifugal blower does not work nearly as well as a positive-displacement type for road racing, for drag racing, or for any type of driving that covers a wide engine RPM range...and the street driving would have to fall into this category..." ___________________________________________So since during YOUR dyno, you mentioned it was 9lbs, this means that you had 2.25 lbs of boost at 3500 rpm. I know you dont believe me, but a roots blower will have its full boost at that level. Evidence of this can be shown by the dyno graph I've posted in my previous post, and will talk about later in this post.As for my statements that arent based in reality, you've already had an owner of a ROOTS BLOWER equipped car tell you're wrong about the charactistics of how a roots blower works on small displacment motors. If that's not reality, I dont know what I can say. I'm sorry you disagree, but you dismiss blanent facts thrown at you as "not in reality". I cannot compete with that. <BLOCKQUOTE>quote:<HR>Plus, your argument is that my power curve is "peaky", but as you can see my torque curve is completely flat and my horsepower curve is completely linear. ...my plot will not fit your imaginary data.<HR></BLOCKQUOTE>a) a flat torque curve means the engine IS PEAKY. Look at every Honda Vtec engine dyno. Flat torque curve. Hondas are what? Oh yes, PEAKY!b) again with the imaginary data. Funny, I see a dyno plot that shows what I'm saying. What is all this imaginary data that I have? Do you think I made the dyno with the 3 curves in MS-Paint?

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Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?

Re: Can a supercharged KLZE handle a small shot of nitrus?