SHO-Z Posted July 6, 2007 Share Posted July 6, 2007 Well I finally figured out how it is going to come together. Still working out the small details, like jetting. I did some calcs on the difference on pressure loss across the ventri between 14.7 psi and 24.7 psi and found that the jets would not need to be that much bigger, but I could be wrong. The supercharger is from an SLK Mercedes with an electric clutch so I can run it when I want to. After what TonyD informed me on having a higher pressure in the float bowls than the carbs I decided the best way is to run a seperate line from the super charger to the float bowls to get the pressure required. I can bleed off some of the pressure with the needle valve if required. The flow loss through the intercooler will take car of the needed pressure differental. I will be running a second air cleaner down stream of the intercooler with a check valve. With about 10 PSI of boost the old 280 engine should get some new life. This is the sketch of about how I hope it will come together. Quote Link to comment Share on other sites More sharing options...
tfreer85 Posted July 6, 2007 Share Posted July 6, 2007 While that looks cool, why not move the SC to the other side of the engine? Less piping, less PSI drop, much easier routing for the IC pipping etc. I think its cool, but it looks like you're going to run out of room with everything on one side. Check out Frank280zx's recent SC mounting, i think its one of the best IMO. Good luck, Tyson Quote Link to comment Share on other sites More sharing options...
Daeron Posted July 6, 2007 Share Posted July 6, 2007 is that secondary air filter for use when not using the supercharger? just making sure im understanding this right.. you are building a setup for "boost on-demand?" with NA for "normal" running? interesting.... Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted July 6, 2007 Administrators Share Posted July 6, 2007 Cool. I take it that you are using some sort of diverter valve that will divert the air around the S/C so the engine will essentially run N/A when the S/C is off, (electric clutch), and vice versa? Is that the M62 Eaton? Please, keep us posted on your carbed S/C project. Should be WAY fun.. You may already know, incase not, C.A.P.A. looks to be a good source of parts and goodies for the Eaton S/C.. http://www.capa.com.au/eaton.htm Quote Link to comment Share on other sites More sharing options...
SHO-Z Posted July 6, 2007 Author Share Posted July 6, 2007 The air filter next to the intercooler has a check valve down stream of it. I am mounting the supercharger where the AC unit use to be. Mounting is simpler there, and this is short shaft design on the supercharger so it need be well forward on the engine. I don't have a top so the AC is worth less. I have not figured out the belt routing and where to find one as short as this one will need to be. This is going to be supercharging on demand. Flick the switch and on it will go. I do think this would be neat on a FI engine! Quote Link to comment Share on other sites More sharing options...
Daeron Posted July 7, 2007 Share Posted July 7, 2007 couldn't you obtain some of the hardware for mounting a power steering pump and adapt that to your purpose? I mean, with a supercharger (rather than turbo) you have the option of placing it on the less busy, less heat soaked side of the engine bay. I am not trying to nitpick, just making sure you have thought of everything I like this idea; what sort of compression ratio were you planning on running? also, refresh my memory.. the line going to the float bowls for the carbs from the SC; that is to add pressure to the fuel supply to held enrich the fuel mixture under boost, correct? am I at least essentially right? Quote Link to comment Share on other sites More sharing options...
SHO-Z Posted July 7, 2007 Author Share Posted July 7, 2007 Being down low I should not have to much problem with the heat. This far forward on the engine all of the air would be passing through the radiator anyway and the temp. difference small. According to TonyD, one of the only members that has any really longtime experience with forced induction webers, the pressure in the float bowl need to be higher than the plenum side or the carbs will lean out. I was thinking about get a plenum from him that had a built in way with baffles to achieve this, but I guess the baffles are missing. So being and engineer had to come up with an alternate solution. The line goes from the supercharger to the top of the float bowls. If I find that the pressure is to high I will use the needle valve to bleed some of the pressure off back to the plenum. Quote Link to comment Share on other sites More sharing options...
TravRMK Posted July 7, 2007 Share Posted July 7, 2007 Sounds like a slick idea. I like it. Pressurised float bowls is used on Boondockers nitrous applications for Snowmobiles/motorcycles to enrich the mixture on them while on the button. A small nitrous line is tapped to the float bowls, and the nitrous pressure pushes more fuel through the main jet, and another line to the intake tract for the nitrous. It works really well. I have a different wet setup on my snowmobile, but their idea of pressurising the float bowl to enrich the mixture is similar to what you are trying to achieve. Quote Link to comment Share on other sites More sharing options...
Daeron Posted July 7, 2007 Share Posted July 7, 2007 According to TonyD, one of the only members that has any really longtime experience with forced induction webers, the pressure in the float bowl need to be higher than the plenum side or the carbs will lean out. Yes, I recall TonyD's posts regarding this fact.. I was trying to make sure I was recalling properly. Just to make it clear, this *is* only an issue under boost, and at zero boost naturally, there is no pressure in this line and no pressurized enrichment needed.. (I am just trying to fully analogize it with an FI forced induction system, which is all I know about.) Your needle valve system sounds interesting; as far as I can tell (like that's worth much) it sounds about right. This is a really neat project, cant wait to see this built. Regarding the placement of the thing, I was just playing the devil's advocate. There is no "right" way, I might've argued for AC compressor side if you had planned it on the other side. Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 8, 2007 Share Posted July 8, 2007 I have been looking at using a Supercharger as well, but like Daeron said I need to put it on the Other side cause living in Florida the A/C Has to STAY! I already have stand alone Efi, and it will be forced thru our 45mm ITB's, with just a set of 6 26lbs injectors. What size Motor is the Supercharger from? 2.3ltr? Kevin Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 8, 2007 Share Posted July 8, 2007 Photos of the Plenum being CNCed/Fabricated now! Quote Link to comment Share on other sites More sharing options...
SHO-Z Posted July 8, 2007 Author Share Posted July 8, 2007 The supercharger is out of a SLK230, and I bought it on Ebay. It is an Eaton M62 with a 1 liter displacement. It is about 12" long overall with 4 thru bolts for mounting. The pulley is larger that any other supercharger I have seen. I found that an after market ford lightning pulley would work and they come from about 8 to 12 psi of boost on a 280 engine. Still would need a center addapter fabed. If you come up with a way to mount one on the other side I would like to see it. Most superchargers I have seen mounted on the spark plug side have been long shafts. With the taped connections on the side of the block for the air conditioner it is just so much simpler You make me feel bad with my 4x4 aluminum plenum compared with what you are having done. I will be fun to see what the final product runs like. Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 8, 2007 Share Posted July 8, 2007 So you are not going to run the Clutch of the M62? Does the Lightning Pulley fit the SLK Clutch? Well I must admit I am a Machinist with a DRO Bridgeport in the Shop so Adapting it to the right side will take more doing for sure, but one I have to do to live in Florida! Plenum? See the base Mounted to our ITB's? we are having BLANK ones made as well so when your tired of your 4x4 Plenum give us a Call! Kevin Quote Link to comment Share on other sites More sharing options...
SHO-Z Posted July 8, 2007 Author Share Posted July 8, 2007 I am going to run the clutch, that is what is neat about this set up. The lighning pulley is for the lower, crank, pulley. I have an exel spread sheet put together calculating lower pulley againt boost levels. I think it is about 3 to one that is required for the 10 psi. Quote Link to comment Share on other sites More sharing options...
Accurate Injection Posted July 8, 2007 Share Posted July 8, 2007 Ahhhhhhh! OK! I was actually looking at the Ford 3.8 Supercharger and I was just going to build a V-Belt Pulley and incorporate it into the Alternator Belt Drive system! I was not looking at the Clutch system until I saw your Thread! Any experience with the Mounting of the super charger itself? Do they have to be mounted flat? orcan they be mounted on there side without starving one rotor bearings? Kevin Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 8, 2007 Share Posted July 8, 2007 The issue isn't that the float bowl HAS to be pressurized slightly higher than the throat (it DOES need pressure at least equal to plenum pressure or at some point boost will push fuel up the gas feed line!) But if you pressurize the float bowl slightly higher than the plenum you can get by with MUCH smaller jets. Otherwise you will have to put Jets into the engine that will flow the horsepower potential of the engine. This way, the jet is flowing under pressure, and not under suction. Fuel level is raised in the emulsion tubes allowing for more fuel than air to be siphoned up the circuit for a richer mixture. The Cartech System Jetting is radically different than the Jetting I ran when I had the HKS Plenum on the same engine. With the HKS Plenum, the jetting was near identical to the jetting used when it was an N/A setup. Actually, when I would pull the turbo system off, it was no big deal driving it around on the 'turbo jets'---I couldn't do that with the simple Non-Segregated Cartech Plenum---it was pig rich at the top end, and needed jets 3-5 sizes smaller. Something like 150's or 170's on Cartech, compared to nothing larger than 135's with the HKS setup. It's been a while since running them, and those numbers may be waaaay off almost 20 years since setup, and 15+ since running it that way, but it was something big like that. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.