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#136
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Not really,
I don't seem to be having any problems with 9 lbs on the stock engine so I'm thinking I'll probably suggest that pulley. I know that's the one JSVXSTYLE wants. Basically when we are all done I'll let you guys decide and if you decide later you want to change it's always an easy swap. Want to pick one of the manifolds out and have me write your name on it with a marker so you can see it and say hey that's mine as work progresses? The black one is Mike's. The white one is JSVXSTYLES You and Duckie can each pick one silver and the last silver is available to whoever buys it first, my suspicion is it will be claimed before the batch is done by someone not wanting to get stuck waiting for the next batch. Quote:
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#137
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Tom(The parts guy ) |
#138
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PS: Do you have an engine map HP / TQ? I'm going to have the tranny rebuilt by Level10 and want to make sure the Torque Converter matches up to the engine map properly. Jonathan
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Good people sleep peacefully in their beds at night, only because rough men stand ready to do violence on their behalf. |
#139
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I think Mike is shooting for a close to stock map. It will be much higher in the numbers but probobly have a very similar curve.
Tom |
#140
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Thanks for the quick response Tom. I appreciate it. That's consistant with what I thought about the map being a bit higher numbers wise, and perhaps a bit flatter. Jonathan
__________________
Good people sleep peacefully in their beds at night, only because rough men stand ready to do violence on their behalf. |
#141
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That's not exactly correct.
I'll try to explain and in so doing you'll see why positive displacement blowers offer so much better performance for this application than any other kind of forced induction could ever come close to. The torque/hp curve you are describing would be a set % increase above the torque/hp curve of the factory engine. What we will get with these systems is a % increase above 100% vollumetric efficiency. Let's say we were running a 7lb pulley--we can expect a %50 increase from 100% ve. That means at the factory peak torque of 4400 rpms where vollumetric efficiency is 99% we will see roughly a 50% power increase. At the factory peack hp at 5600 rpms ve is still 97%, pretty close to 100% and we will see roughly a %50 power increase. However, where ve is low the difference being made up to get to 100% ve before the 50% over increase will become hugely significant. This is in the lower rpms. Say you pick a place where ve is 75%. You are getting a %25 + %50 increase of 100% ve. You were starting at 75% so the 75% gain is a 100% power increase. The hp graph will be approximately a 45 degree line. To come up with estimates for level 10 (or for the hell of it) take the known factory value of 230 hp at 5600 rpms and devide by .97 then multiply by 1 + 9/14.7 which gives you 382hp. Put that value at 5600 rpms and draw an upward sloping 45 degree angle line through that point. That's your approximate hp plot. There is a formula you can use to calculate tq from hp to derive a torque plot. Quote:
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#142
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I'll stop talking now
Tom |
#143
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wouldn't you be multiplying 230 by .97 (since your ve is 97%) and then multiplying this by 1.6122, which would give you 359.7 hp? If you divide by .97 you'll actually get 237 hp... -Bill
__________________
Retired NASA Rocket Scientist Most famous NASA "Child" - OSIRIS-REx delivered samples from asteroid BENNU to Earth in Sept. 2023 Center Network Member #989 '92 Fully caged, 5 speed, waiting for its fully built EG33 '92 "Test Mule", 4:44 Auto, JDM 4:44 Rear Diff with Mech LSD, Tuned headers, Full one-off suspension '92(?) Laguna, 6 spd and other stuff (still at OT's place) My Locker |
#144
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That's the whole point Bill. I'll try to explain again, if you don't get it let me know. The ve of the engine with the supercharger is an increase above 100% ve not whatever the ve is of the engine without the supercharger. I'll try another short explanation here. The hp output on the factory engine at 5600 rpms is 230hp. The ve of the factory engine is .97 at 5600 rpms. That means that while ingesting %97 as much air as the engine will theoretically hold without forced induction it generates 230 hp. If you devide 230 by .97 you get how much hp the engine would generate at 5600 rpms if it ingested all the air it can theoreticall hold without forced induction, 237.11hp. That is the estimated hp output at %100 ve. That's the gain you make with the blower before you start seeing an increase in manifold pressure. Think of a glass--you have to fill it before your cup can runeth over. A positive displacement blower puts out a fixed amount of air with every revolution. The vollumetric efficiency of the engine is replaced with the vollumetric efficiency of the blower wich for a twin screw blower is basically perfect at any rpm. That's why your power output is a 45 degree line and not a curve. Every time you spin the input shaft of this blower it puts out 1.6 liters of air no ifs ands or buts. If you double your rpms you double the amount of air ingested...1 to 1 rise over run..that is a 45 degree line. Now if you go back and look at lower rpms where the vollumetric efficiency of the engine is low, revist the example of 75% i gave, you will see the math behind the huge low rpm power gains with a positive displacement blower. I encourage you to print a svx power plot, put your dot up there at 382 hp at 5600 rpms, and draw a 45 degree line through it so you can see where the line falls. The gain will be 61% at 4400 rpms and higher everywhere else--much higher at low rpms. It's also worth noting that your power no longer peaks at 5600 rpms but continues to climb as rpms do. |
#145
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Ymmmmmm, Tasty. You can go ahead and put me down for the 9lb set-up. The more power the merrier.
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#146
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Got it as soon as I read the first paragraph of this post I was reading your previous post to mean that the stated 230 hp assumed 100%ve, but that 97%ve is more realistic - thus my response. I'm totally with you now! -Bill p.s. and the power will continue to climb to the mechanical limit of the engine....
__________________
Retired NASA Rocket Scientist Most famous NASA "Child" - OSIRIS-REx delivered samples from asteroid BENNU to Earth in Sept. 2023 Center Network Member #989 '92 Fully caged, 5 speed, waiting for its fully built EG33 '92 "Test Mule", 4:44 Auto, JDM 4:44 Rear Diff with Mech LSD, Tuned headers, Full one-off suspension '92(?) Laguna, 6 spd and other stuff (still at OT's place) My Locker Last edited by SVXRide; 07-05-2005 at 02:35 PM. |
#147
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Blowen in the wind.
Michael, at what engine rpms does the engine accept the full 9psi. Straight off idle?
Harvey.
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One Arm Bloke. Tell it like it is! 95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels. 97 Liberty GX Auto sedan. 320,000Kls. 04 Liberty 30R Auto Premium. 92.000kls. |
#148
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Yeah, if you floor it from idle it will go straight to 9 lbs and no no problems except tire wear. Of course in practice I don't do that very often. With all the power I don't use much gas on the street.
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Michael Emery, MBA, MS 94 SVX LSI, Ebony Pearl profile 94 SVX LSI, Ebony Pearl from back Performance and Multi-Fuel Tuning Last edited by longassname; 07-05-2005 at 08:11 PM. |
#149
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Harvey.
__________________
One Arm Bloke. Tell it like it is! 95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels. 97 Liberty GX Auto sedan. 320,000Kls. 04 Liberty 30R Auto Premium. 92.000kls. |
#150
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You're asking if detonation is a problem at high load and low rpms? That's an interesting question. As far as load in the usual sense of how much air is injested is concerned with the blower 9 lbs is 9 lbs is 9 lbs no matter what the mechanical load placed on the crankshaft is. Now would a higher mechanical load increase the likelyhood of detonation? I don't know, you think? |
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