Power AdderGetting a Supercharger or Turbocharger? Thinking about using Nitrous? All forced induction and N2O topics discussed here.
Welcome to ThirdGen.org!
Welcome to ThirdGen.org.
You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!
Does superchargers are called centrifical superchargers they work like turbos except they use belts instead of exhaust to power the compresser
you probably could, but the compressor wouldn't spin fast enough with out a gear box multiplying the RPM. But to answer your second question, yes, instead of exhaust they use a belt off your crank to spool up.
Mother of all that is some serious plumbing!!! I thought my compartment was *tight*. Anyway whats the deal with the belt that drives it? It looks like its about a 1/2 an inch long?
If you look closely at the pictures there is some kind of step up ratio to get the impeller to spin faster. The shaft with the pulley on it is not inline with the center of the compressor housing. there has to be a gear multiplication in there.
Originally posted by Zac's92 If you look closely at the pictures there is some kind of step up ratio to get the impeller to spin faster. The shaft with the pulley on it is not inline with the center of the compressor housing. there has to be a gear multiplication in there.
exactly; and it spins that compressor up at around 60,000 + rpm
Yes, those are two superchargers that he built using the compressor half of two huge turbos and the gearboxes from a electrical wheelchair. The grearbox is a step down from the electrical motor to the wheel axle, but he is running it backwards as a step up gerbox instead. The belt pulley is on the wheel axle.
If you look you will also see that he made the dump valve and fuel pressure regulator from billet aluminum. The box behind the right headlight is an air-water chargecooler that he also built.
He is having some problems ... He is blowing the pipes apart and the chargecooler exploded in half ... but that has been repaird and should be much stronger now.
I can imagine that some of you wonder why anyone spend time to install a 2 stage compressor under the hood.
I have since the last 4 years a homebuild single centrifugal compressor installed (se pictures above), based on a Schwitzer truck supercharger with very good result. Maximum boost with this setup is 7,5 psi at 75 000 rpm. My goal is from the beginning to see how strong an almost standard 350 TPI can be, because of the TPI intake is this engine not a high hp setup but very strong at low rpm.
355 TPI
8,5:1 CR KB pistons
Compcams camshaft (for supercharged engines)
1 5/8" headers
Saab Aero injectors and boostpump
Computer is a standard xxx165 ECM MAF rebuild to a Holden xxx808 MAP (2 bar Buick)
Techedge Wide band lambda + EGT
With the new compressor based on a KKK supercharger in serial with the Schwitzer compressor I expect to see 20 psi boost at 5500 rpm and no belt slip.
I have run this 2 stage setup for a couple of weeks and it seems to work, high average hp that suits my 2.73 rearend (except a few bugs like a exploded aftercooler). Two hours ago my th700 went to heaven, maybe time for a 4l80e.
I must correct my last reply, 20 psi of boost is what the compressors are capable to generate for the required cfm. The higher boost the better,then I can get high boost at low rpm and at 5500 rpm(engine) bleed out air to the atmosphere thru an adjustable regulator (big pressureregulator controlled by a electric solenoid) to avoid too high pressure. Maybe a turbo supercharger have been better to achieve this, but this is a more unusual solution.
Pressure between the compressors are theoretically 7,5 psi at 5500 rpm (have not been able to measure that yet) then the 2nd compressor will se higher airdensity and boost the pressure up to 18-19 psi. // Schwitzer
Originally posted by schwitzer I can imagine that some of you wonder why anyone spend time to install a 2 stage compressor under the hood.
Makes sense to me… it’s a cool bit of “doing it your own way” mixed in with “can you make it work…”
Quote:
355 TPI
8,5:1 CR KB pistons
Compcams camshaft (for supercharged engines)
1 5/8" headers
Saab Aero injectors and boostpump
Computer is a standard xxx165 ECM MAF rebuild to a Holden xxx808 MAP (2 bar Buick)
Hum… can you elaborate on this? Are you saying that you’re running your standard 165 with a 2 bar map in the place of the maf? If so I’d love to hear details since I don’t think I’ve heard of anyone doing something like that (closest is probably converting the GN maf setup to map) and I have a car with a 165 in it that will eventually see some boost.
Quote:
Originally posted by B4Ctom1 I wasnt knocking it as a matter of fact I would like to know what kind of pressures are seen between them
I’m betting (correct me if I’m wrong Schwitzer) that part of the deal is that you can’t really spin up the compressors to where they typically would spin up to driven by a turbine so the staged setup is to accommodate for the bigger compressors spinning slower. Centrifugal superchargers use the same basic layout of a turbocharger, but use compressor wheels designed especially for the lower rpm’s that they typically see.
Huh, that raises an interesting question… what did you do for the gear box output shaft bearings, anything special? Not many bearings are rated for 75,000rpm and the setup used in turbos will not play nice with the side loads that you’d get from a gear box.
Crossfire: Go to DIY PROM board and do a search for 808 code and you will find all the info you'll need.
(MAF to MAP posts)
You could also run a 2-bar MAP with the 730ECM the same princip. But with the 808 code you can use your old 165 ECM and dont have to repin and so on.....
__________________ GTA -89:415cui 749ECM+$59code+ p/h injectors+Procharger F1 + 4L80E
Originally posted by 83 Crossfire TA Makes sense to me… it’s a cool bit of “doing it your own way” mixed in with “can you make it work…”
Hum… can you elaborate on this? Are you saying that you’re running your standard 165 with a 2 bar map in the place of the maf? If so I’d love to hear details since I don’t think I’ve heard of anyone doing something like that (closest is probably converting the GN maf setup to map) and I have a car with a 165 in it that will eventually see some boost.
I’m betting (correct me if I’m wrong Schwitzer) that part of the deal is that you can’t really spin up the compressors to where they typically would spin up to driven by a turbine so the staged setup is to accommodate for the bigger compressors spinning slower. Centrifugal superchargers use the same basic layout of a turbocharger, but use compressor wheels designed especially for the lower rpm’s that they typically see.
Huh, that raises an interesting question… what did you do for the gear box output shaft bearings, anything special? Not many bearings are rated for 75,000rpm and the setup used in turbos will not play nice with the side loads that you’d get from a gear box.
Yes, my relative small compressorwheels have that disadvantage. I´m running them at the lower end of the compressormap (effic.), they should run at 110 000 rpm for best result. That´s the reason for my 2 stage coupled superchargers.
The biggest problem from beginning is bearings and output shaft, outputshaft must be as short as possible and the bearings must have large clearence (gap between moving parts).
Today I use 6202 ZTBH C3 bearings rated only 40 000 rpm, they can stand one season and are cheap (20$ each).
Yes I use my old 165 MAF with 2 bar MAP, it works fine. Some cables must be relocated and some tables must be rescaled but this is simple. You will also lose your knockretard, in my opinion they have too many false signals especially when using a colder thermostat (more noise from engine). Instead I uses a medical stetoscope bolted beside knocksensor, then I can hear pinging with my ears. Have also connect ESC module to a LED for visual control.
) T-tops, WS6, sold 7/23/02
WWW.OUTLAWPERFORMANCE.COM
