SHO-Z Posted July 3, 2007 Share Posted July 3, 2007 What type of boost are you planning on running? There is going to be a large drop in boost when the supercharger goes into bypass. I did a simple look at it using my boost spread sheet. Using 10 PSI of boost from the supercharger as a base line and 10 going to it from the turbo will give you 28 psi to the engine. When you drop the supercharger of you are really going to get power drop. There are other dynamics involved in this and I do not believe to would be the entire 18 PSI change but it would be well over half of it. If you want a real flat power curve you might want to feed the turbo with the supercharger. There will be a point where the supercharger cannot keep up with the turbo’s air demand and a simple flapper valve could open and the super charger not doing any work of compression would be spinning with very little HP loss. Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 3, 2007 Share Posted July 3, 2007 Traditionally, the supercharger is bypassed at idle ONLY. The reason being is the positive displacement, linear delivery of the supercharger will simply overheat the air when an insufficient amount of flow is going through it. Pete (ZYa) was experiencing this on drop-throttle I believe. Temperatures soaring even though there was 'no boost'---well taking -15psia and compressing it to -10 psia is a BIG compression ratio, and makes a LOT of heat. So you bypass it at idle or closed throttle just so the thing doesn't heat up the air excessivley. In this case, on drop-throttle, the supercharger would bypass much like a BOV (which would be routed similarly...though it could be put on the SC Discharge to dump pressure as well...would have to work out those dynamics) and instantly close upon reapplication of the throttle---boost would resume instantly due to high input. There will be tuning issues with having the BOV for the Turbo lag the bypass action of the S/C. You want the Turbo to push air to the S/C simply to keep it's pressure up and spooling. Only once the air stagnates do you want to dump excess Turbo Boost from the plenum to the S/C. Otherwise on reapplication of the throttle, the S/C will be spinning fast, and literally suck the turbo discharge to a vacuum while the turbo tries to catch up... This may make for a better dump valve design in that you use your BOV on the portion of the plumbing between the S/C and the T/B, and just let the turbo stay spooled and use the S/C to keep sucking on it preventing surge. That would probably be the most effetive and troublefree way to do it. Basically what I'm getting at is the S/C needs to bypass at idle for extended periods to prevent heat buildup, but has different on-boost tendencies that would require different venting then... Quote Link to comment Share on other sites More sharing options...
mtcookson Posted July 7, 2007 Share Posted July 7, 2007 Looks real good! This setup is where a true intercooler is used. When you have a cooler between two compressors (the turbo and s/c in this case) it is considered an intercooler. The cooler after the s/c, between it and the engine, is called an aftercooler (technically every single turbo and s/c setup with a cooler between it and the engine is called an aftercooler, but is labeled incorrectly as an intercooler) . Just a little tidbit of info that not many people know about. Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 8, 2007 Share Posted July 8, 2007 Actually, Intercooler is the proper term in either case. On a Turbo blowing into a Supercharger, it's intercooling between three stages of compression (three compressors) one dynamic (the turbo) and two positive displacement (the S/C and the Engine). On a Turbo blowing straight into the Engine it's the same thing, but the difference is a Dynamic Compressor blowing into a positive displacement compressor (reciprocating) in this case the engine. People forget the pistons are acting as a rudimentary and basic Air Compressor, operating at a compression ratio of anywhere between 7:1 and whatever.... The Aftercooler is an interchangable term for cooling after compression...And intercooler is an after cooler--but generally aftercooler is only applied to the cooling done before the discharge of the compressor package to the air system. In other words after all compression is complete. In any Internal Combustion Engine with forced induction, all external forms of compression before the engine are intercooled---as the Engine is the final stage of compression. People forget that engines are compressors, and that the quest is to decrease 'pumping losses' to increase efficiencies....decreased pumping losses mean more HP down to the road. Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 9, 2007 Share Posted July 9, 2007 I would be courios what a Supercharger only Dyno Pull looked like! How wide is that Blower? The Height and the Length from center of Pulley to TB Face? Could you get those numbers for me Please? Kevin Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 9, 2007 Share Posted July 9, 2007 Wondering of this would be an easier Mounted on the Passenger side! It also looks to have a Dip Stick in the Blower! It's a Toyota 2.4 Application as well! Looks to Have a Electric Bypass Valve as well! Anyone have any experience with this unit? Kevin Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted July 9, 2007 Share Posted July 9, 2007 Is that bypass valve just a butterfly valve like on a TB but with a motor on it? Cool. Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 9, 2007 Share Posted July 9, 2007 I blew up the picture, and theres more than 3 wires so it may be a stepper motor! They usually have 4 wires! It's hard to tell any way! Looks to have the Same Clutch as the Mercedes unit! Kevin Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 9, 2007 Share Posted July 9, 2007 The Toyota unit is a popular L20B swap for the 510 Guys...expecially if they start playing with the Z22 and Z24 bottom ends! I was in negotiations with someone in OZ to buy his 510 setup that utilized the Toyota SC. He didn't employ the bypass, but said when declutched the rotors freewheeled under engine vacuum, so the pumping losses didn't bother him that much! LOL Fell through when his other buyer came up with money before we determined the shipping costs. Can't fault him, shipping overseas can be a PITA...And things to OZ seem to take forever to get there...coming this way doesn't seem so bad, though. Strange, huh? I digress.... Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 9, 2007 Share Posted July 9, 2007 Tony: Is it the same size M62 as the Mercedes unit? If So it may be a little Small for the 2.8 ltr? Wonder what CFM at 7PSI it's Flowing? Anyone know? Kevin Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 9, 2007 Share Posted July 9, 2007 I'm not sure. I know the one Frank is mounting is the one from a Buick 3.8L Engine, so it should have no problem flowing correct amounts of air in his application. Quote Link to comment Share on other sites More sharing options...
Vindicare Posted July 9, 2007 Share Posted July 9, 2007 The toyota unit is no where near as efficient as the eaton unit. Im pretty sure the toyota one actually has plastic rotors which limit's its longativity and it has the clutch arrangement because it is not meant to be run for long periods due to heat. There is a guy in AUS that used one on a RB30 and while spinning it at 70% of its max rpm(made 131rwkw) it produced a max of 5 psi(He is now twincharged with a m90 and a gt40? turbo, u've all probly seen his movies on youtube ). One of my friends is just about to put one on a draw through setup on a 179ci engine but am unsure as to the speed he's going to run it at. It's quite a popular budget blower, but only because it is reasonably cheap. However, over in the US i see no reason to not use the M90 as they are so cheap over there, i managed to get a M90 shipped to Australia for $300AU(the toyota units usually go for about that much over here), although they are not always that cheap, there is not a significant difference in the average selling price. I pose a question to everyone, how would i go about getting a pulley to drive this type of supercharger attatched to a crank pulley? It's something i've never really thought about or asked about before. I've been planning to go supercharged for a year now, but have onyl just recently(better paying job) decided to go quite serious about it with heavy porting and all the expensive stuff that goes along with the chase for power. thanks Aaron Quote Link to comment Share on other sites More sharing options...
SHO-Z Posted July 9, 2007 Share Posted July 9, 2007 I am planning on getting one of these on my slk230 supercharger http://www.rpmoutlet.com/lightaspm.htm and fabing up a new center hub. I would like to get my hands on one of the center hubs for the ford and see if I can make it work. Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 10, 2007 Share Posted July 10, 2007 I know someone out there makes a Serp Crank Pulley for the L Series Motors, but for the life of me I can not remember who! I was just going to Machine a V Pulley for the Blower to see if it all worked out, then upgrade later to a Serp system if needed! Kevin Quote Link to comment Share on other sites More sharing options...
Vindicare Posted July 10, 2007 Share Posted July 10, 2007 Hey Kevin, If you could find out for me that would be great. To be honest the v-belt is not up to the task, this other guy said it was slipping often unless it was really tight. but if you want to try that's fine. That's a very nice intake you guys have designed, will having the fuel rail inside not cause some bad turbulence? Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 10, 2007 Share Posted July 10, 2007 Hey Kevin, If you could find out for me that would be great. To be honest the v-belt is not up to the task, this other guy said it was slipping often unless it was really tight. but if you want to try that's fine. That's a very nice intake you guys have designed, will having the fuel rail inside not cause some bad turbulence? Vin: I am Sure it will, but when your injecting STUFF that you can not see Burn it may be worth it in the long run! This is something with the HELP of SUPER Dan we aim to find out! That plenum will work with or without the additional Injectors inside, it will also fit with our ITB's to the RB26DETT Lower Manifold as well! When our 50mm ITB's are ready they can take the place of the 45mm ITB's and give the RB guys a Larger Throttle Body that will allow them to be Tapered to the 45mm Stock Lower to create a Nice RAM Horn From the Airhorn to the Stock Lower Manifold! Vin I looked and Looked for that Lower Serpentine Crank Pulley and Can not find it now! Strat a New Thread and Ask who does know where! Some one on here has to know! He wa advertising it as a SERP conversion for Datsun L series! sorry I could not help more! Kevin Quote Link to comment Share on other sites More sharing options...
Vindicare Posted July 10, 2007 Share Posted July 10, 2007 Thanks mate, I searched and found a thread i remember reading and saved the pictures from ages ago, but i didn't really understand till just then haha. There's a thread where kjones put up pictures of the method he is using to run his supercharger setup, i went out and then had a look at the f54/p90 engine i have waiting to be lavished, but it does not run the same balencer that ken has, but then i looked at my l24, and it runs the same one ken does and all i need to find is a pulley, which i may just go get made up by someone...... but anyway, i might just buy a new dampner and hope i can find a way to attatch a pulley. Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 10, 2007 Share Posted July 10, 2007 Hey Vin: Give me a Link to the thread then I would like to see it as well! What kind of Power was that set-up making? Kevin Quote Link to comment Share on other sites More sharing options...
Vindicare Posted July 10, 2007 Share Posted July 10, 2007 Sure! here it is. He never got it dyno'd from what i can see(i also asked a while ago) He guesstimated it to be around the 300hp level unintercooled. running 12 psi i think over running the charger some. m62 i think it was http://forums.hybridz.org/showthread.php?t=117342 Quote Link to comment Share on other sites More sharing options...
alexdeprat Posted July 10, 2007 Share Posted July 10, 2007 I know someone out there makes a Serp Crank Pulley for the L Series Motors, but for the life of me I can not remember who! I was just going to Machine a V Pulley for the Blower to see if it all worked out, then upgrade later to a Serp system if needed! Kevin Kevin, I believed that it was Dave from Arizona Z that use to sale a Serp Crank Pulley for the L Series Motors few years back, I am sure that he can give you all the inside and outs about it, Dave is a great guy, give him a call. Alex Quote Link to comment Share on other sites More sharing options...
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