Garett 103 Report post Posted June 16, 2011 you'll need to factor in the superchargers efficiency into that equation as well. But as everyone is starting to say your going to need to sort out a way to tune it. I forgot to ask what ecu it is currently running on? i cant remember what the part number is of i as its been 25,000k since i built the engine, its the standard 2.5l m50 403 maybe?? Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 16, 2011 dont forget superchargers take 33% of crank power to rotate and the sc14 isnt that big should run max 12psi based on the specs i have here due to bearing failer and intake temps, there ok on little engines up to 2ltr. get a screw blower like sprintex or whipple Does that mean i have to make over 33% power increase for it to be worth doing??? Yeah it shouldn't be to bad for 8psi at full rev's i have a small intercooler was going to put before charger seens as i have it already and going to get a long one for the front behind the bumper between the fogs. Quote Share this post Link to post Share on other sites
thorburn 121 Report post Posted June 16, 2011 The supercharger will not take 33% throughout the rev range. Where does 33% come from? i've seen it written before. The pressure difference before and after the sc will determine the work needed to rotate the sc. Internal friction of the sc will add to this Has the ecu been chipped to suit the extra .3L's? Quote Share this post Link to post Share on other sites
No name user 379 Report post Posted June 16, 2011 The supercharger will not take 33% throughout the rev range. Where does 33% come from? i've seen it written before. The pressure difference before and after the sc will determine the work needed to rotate the sc. Internal friction of the sc will add to this Has the ecu been chipped to suit the extra .3L's? ok this is what ive found after 25yrs doing this as such and installing sc that you lose 33% crank hp to drive a sc on average thus you gain 100hp you lost 33 driving the sc, turbos consume around 5-7hp based on parasitic drag. eg:i did a 1000hp sc ski boat changed to two turbos it made 1315hp. topfuel blowers use around 1000hp to drive a blower and thats a screw blower which have alot less drag than a roots whyll they make over 7000hp do a google. pressure before and after shows it efficency and before its using atmospheric of 14.7 like all applications do,pressure after is based on how hard your spinning it or its displacment to feed set cu in motor thus small blows become a restriction or wont pump enough to feed the hp your after thus why they all come with a cfm rating. Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 16, 2011 The supercharger will not take 33% throughout the rev range. Where does 33% come from? i've seen it written before. The pressure difference before and after the sc will determine the work needed to rotate the sc. Internal friction of the sc will add to this Has the ecu been chipped to suit the extra .3L's? no not at this time, im just in the beginning stages of this upgrade. so this i will look into soon, i have another car which i can drive in the process and is for sale everyone haha heres the link http://www.trademe.co.nz/Browse/Listing.aspx?id=382048236 Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 16, 2011 ok this is what ive found after 25yrs doing this as such and installing sc that you lose 33% crank hp to drive a sc on average thus you gain 100hp you lost 33 driving the sc, turbos consume around 5-7hp based on parasitic drag. eg:i did a 1000hp sc ski boat changed to two turbos it made 1315hp. topfuel blowers use around 1000hp to drive a blower and thats a screw blower which have alot less drag than a roots whyll they make over 7000hp do a google. pressure before and after shows it efficency and before its using atmospheric of 14.7 like all applications do,pressure after is based on how hard your spinning it or its displacment to feed set cu in motor thus small blows become a restriction or wont pump enough to feed the hp your after thus why they all come with a cfm rating. this is very interesting thanks crunchy... Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 16, 2011 i worked out i need a crank pulley of 174mm to get 8psi boost at 6700rpm spinning charger at 10,152rpm as the clutch pulley diameter is 115mm, Sound correct?? Quote Share this post Link to post Share on other sites
No name user 379 Report post Posted June 16, 2011 i worked out i need a crank pulley of 174mm to get 8psi boost at 6700rpm spinning charger at 10,152rpm as the clutch pulley diameter is 115mm, Sound correct?? if you copy off the oem setup you got it from you cant go to wrong, from mem you cant spin them any harder than 14k Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 17, 2011 what do you think about running the sc all the time with out a clutch??? to get around the over fueling problem when not turned on. Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 17, 2011 I found this site that has a 77mm sc14 pulley.. better idea?? http://www.pulleybros.com.au/page4.php Quote Share this post Link to post Share on other sites
Ben 0 Report post Posted June 17, 2011 (edited) what do you think about running the sc all the time with out a clutch??? to get around the over fueling problem when not turned on. = best I found this site that has a 77mm sc14 pulley.. better idea?? http://www.pulleybros.com.au/page4.php Size up a pulley from an RB20/25 alternator. When i looked into using sc14 i THINK that was gunna give me bout 10psi on m50b25 Using existing aircon pulley on engine and replacing SC pulley with RB alternator one Edited June 17, 2011 by Ben Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 18, 2011 = best Size up a pulley from an RB20/25 alternator. When i looked into using sc14 i THINK that was gunna give me bout 10psi on m50b25 Using existing aircon pulley on engine and replacing SC pulley with RB alternator one its all mounted up (mock up job) took me half a day i got a 6pk2240 for it only just fit, im getting a bigger belt for it tomorrow, while i was there i put the lighter harmonic balancer of the m52 on, happy days... i started it up with the belt on sh*t that sc14 blows some air haha, cant wait to do the pluming Quote Share this post Link to post Share on other sites
thorburn 121 Report post Posted June 18, 2011 pictures Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 18, 2011 (edited) pictures i got some pics but they are nothing pretty haha i found some channel steel lying around and used that is a lil rusty looking but still really strong. once i know that all is good and running right ill take them off copy and enhance. Edited June 18, 2011 by Garett Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 23, 2011 ok so i took the day off work yesterday and made my outlet manifold for the sc14, happy as with it. i will need to relocate the battery to the boot to make room for my new alloy piping (Free) thanks to a friend and run my wires for the switch which will look like a ac button tomorrow night, man i love midnight autos haha... total cost to date is $293 $250 for sc $40 for longer belt and $3 dollars for 3 1mm cut off discs plus my time 2 days.. Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 23, 2011 More.. Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 23, 2011 Hey does a m52 harmonic balancer 1st crank pulley fit on the m50 its a sh*t load lighter... Turns out yes it does haha just have to drill one small locator hole, happy days Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 25, 2011 ok so today i put my battery in the boot to make more room under the hood, worked out quite well i might add.. i also put in a kick down switch, and ran the wiring for the charger, positive on a fuse to fuse box, negative or earth i run to the kick down cable and on to a demister pull switch out of a 2002 because it was green and that means go haha i had to wire it up a lil different to how the switch was designed for but i got the desired effect, light comes on when using the kick down off when not. light also comes on when switched on via the pull knob, i think its in the perfect location too right by the shifter tomorrows mish is finish the pluming and go for a drive... Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 26, 2011 The basics are now done charger is all plumbed in i dont know what its boosting yet but i know it is very noticeable differance i floored it around a round about in second it stepped out with ease where before it struggled, total price to date is 350 with around $57 for silicone hoses and 3 days work. i will post more pics soon.. im loving the button on the pedal, cant use it on the switch as it has no bov at the moment, there are still a few things to iron out and improve. does anyone have any questions?? Quote Share this post Link to post Share on other sites
polley 916 Report post Posted June 26, 2011 does anyone have any questions??Can I come for a look / ride? Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 27, 2011 Can I come for a look / ride? Yeah sure why not, once its all finished though. shouldnt be too much longer haha i hope. Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 27, 2011 (edited) I have got a little boost leak from the manifold sealing surface but i got some thick plate ill need to re do that , no biggy, and haha i put the Idle control Valve piping in front of the charger which ill need to move to after the charger so thats causing a boost leak too, so that and BOV go in tomorrow after work, and i need a boost guage... i love freebes Edited June 27, 2011 by Garett Quote Share this post Link to post Share on other sites
thorburn 121 Report post Posted June 27, 2011 (edited) +1 Didn't realise 325's had the battery in the front What injectors did you end up using? What is the supercharger being run off? Just a longer belt that links off the standard belt drive? It's quite impressive When is the video coming? Have you done something for the crank case ventilation Edited June 27, 2011 by bbs Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 27, 2011 I have got a little boost leak from the manifold sealing surface but i got some thick plate ill need to re do that , no biggy, and haha i put the Idle control Valve piping in front of the charger which ill need to move to after the charger so thats causing a boost leak too, so that and BOV go in tomorrow after work, and i need a boost guage... i love freebes or i could just run a pcv ie one way valve for my icv hose that should do it.. ill suss that out tomorrow too, hmm Quote Share this post Link to post Share on other sites
Garett 103 Report post Posted June 27, 2011 +1 Didn't realise 325's had the battery in the front What injectors did you end up using? What is the supercharger being run off? Just a longer belt that links off the standard belt drive? It's quite impressive When is the video coming? haha yeah the pre 92s have the bat up front... i havnt changed my injectors yet but will once i install my bov that way i can run it all the time if i like, the chargers being run off a longer 6pk belt with the add of a pulley a 6pk2260 to be exact so it runs off the slighty larger crank pulley of the two. once i have the leaks sorted find out what its boosting if not enough ill change the charger pulley. im glad to hear its impressive.. you having seen pics yet haha at this stage its not impressive to look at ill post some pics... Quote Share this post Link to post Share on other sites
