i have a sn2000 blower on my 89 stang it was rebuild 2 years ago by paradise ??? i want to know if i can put another pully to get more power out of it can it take it ???? and or some other tricks thanks
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i have a sn2000 blower on my 89 stang it was rebuild 2 years ago by paradise ??? i want to know if i can put another pully to get more power out of it can it take it ???? and or some other tricks thanks
Either go with a 3.75" pulley on the Supercharger or get a 7" crank pulley. IT really depends on you combination but you will see about 7psi at 4500 rpm. Just don't over-rev it or you could damage the impeller short shaft that the balls rotate around. ASP has you pulleys and they around $59.
[QUOTE=speedytang]Either go with a 3.75" pulley on the Supercharger or get a 7" crank pulley. IT really depends on you combination but you will see about 7psi at 4500 rpm. Just don't over-rev it or you could damage the impeller short shaft that the balls rotate around. ASP has you pulleys and they around $59.[/QUOwhat you mean dont overturn the blower whats that mean my car stops making power at 5600 rpm is that to high for the blower or ??? what boost will i get at 5700 rpm thanks.
what you mean dont overturn the blower whats that mean my car stops making power at 5600 rpm is that to high for the blower or ??? what boost will i get at 5700 rpm thanks
The SN series supercharger has a maximum impeller speed of around 40,000rpm. Anything over this maximum is overturning the blower and subjects the blower to increased heat and friction which causes wear. This will damage the blower and require a rebuild. If you run the stock 6" crank pulley and 4" blower pulley your supercharger will be spinning 39960rpm @ 6000rpm (engine rpm). If you go to a 3.75" blower pulley and keep the 6" crank pulley your impeller speed will increase to 42624rpm @ 6000 engine rpm. This will increase your boost but also increase the wear on internal parts of your supercharger. You can figure out the impeller speeds using the equation below.
Crank Dia./Blower Dia. x RPM x Blower Ratio = Impeller Speed
The blower ratio of SN series Paxton blowers is 4.44:1
can i put an oil cooler on it is there such a thing ,that way it will keep it cooler and make it last
The SN2000 does fine at 45000 rpm but DO NOT miss to many shifts or you will over rev the unit. The cooler will help keep the temperature down for every day use and gives more boost because the cooler fluid allows the ball drive to get traction on the internals. Now what I am getting ready to tell you I am not recommending just telling you my setup. I run a VR4 which is the race ball drive. I have street driven and raced the unit for 6+ years and run a cooler. I race the car and shift at 6800rpm have a 3.75" and a 7" crank pulley. This supercharger I take apart and inspect every winter and at 40k miles on the supercharger just replaced the rear seal which was a new design from the SN2000. I replaced the Impeller shaft and Balls last year but they really showed no damage but went ahead and got the parts from Paradise just in case they went belly-up. I have a 3.5" pulley ran it once and seen 15psi but for the street I didn't need it since I can build 12psi at 5800 rpm with the 3.75" and on the street I usually shift no higher than 5500rpm anyways. The reason I am giving warning is not really the rpm but it is a factor, but that I have a Billet Impeller and it can handle the 60k+ rpm without destroying itself and sending parts into the intake manifold.
This was actually what i was looking for right now! Thanks! :cool:Quote:
Originally Posted by PropheZ
hmmm k my car with my setup on the dyno my car makes power up to 5600 rpm and i have my rev limiter set to 5600 rpm so i cant really over rev the blower i think lol so what basically should i just change the pully??? maybe you can give me more details now that you know i can only rev up to 5600 rpm thanks.
You can still over rev the blower. Just because you shut off spark or fuel does not mean your engine or blower will not do a rpm spike. Example. Set your rev limiter at 3000 rpm then hold the throttle open at that setting and put the clutch in or put the car in 'N' and you will see your tach rev and probably go past 7k rpm. Without knowing your engine setup you could probably be out of steam at 5200 rpm anyways and just be pushing throttle for no real increase. Nothing is as simple as it seems. Give some car background and maybe I can give you my personal opinion if it is worth going over 6psi or not.
backround as what you mean . what i have done to the engine
Give some engine information
i got full exhaust with long tubes no cats b303 cam explorer upper lower 70ml throttle body 255 fuel pump just msd ignition no btm and set at 5600 rpm thats about it and as well the sn2000 with at 6 pounds of boost also if i want 9 pounds of boost what do i need and is that going to much thanks
Change the FMU disc, Put plugs at .032-.035. Change to a 3.75" pulley and you might see 8psi and to bad you have the 'B-303' cam because it is costing you power and the stock cam would be much better. You really need some type of BTM. Set timing to 14 degrees and have the BTM pull back 1 degree for every 1psi of boost. Have you ran it at the track yet to give timeslip numbers so can get a rough estimate of horsepower.
I have a simular set up on my car, I have a stock cam but was going to go to a B-303 But after hearing what you said Perhaps I wont, Why is the stock cam worth more power?What size disk in the fmu? Will the blower last with these mods? ThanksQuote:
Originally Posted by speedytang
the best time i did was 13.50 at a 108.88 cause i dont have a tire and my 0 to 60 is like 2.5 2.6 garbage i dynoed the car i got 323 at th rear wheels you sai dto change the disc on the fmu well i not using the fmu cause it was bogging over 4500 rpm so i kinked the hose and what cam do i use and what diff would there be more power or ???
So what size injector are you using since you are not using a FMU. Kink the Hose, what is that. 'B-Cam" is a Carb. camshaft and the duration and centerline is incorrect for building power for forced induction. Use eaither the stock cam or get a custom style cam for forced induction but if you need to worry about emissions use the E-Cam and it seems to do really well.
How good is the stock cam? Is it worth getting a blower cam or just keep it stock?
i have 24 pound injectors and the fmu was hooked up but when it was the car was bogging so i pulled the little hose that goes from the fmu to where ever and tied blockin the air and that stopped the bogging prb
crazyhorse88, Keep the stock cam, With a rather stock car I make 483 rwhp with only 10psi and had no problems and it still drives like a stock car around town even in 100 degree weather. mani, You will not be able to build any more boost with the 24lb injecters without the FMU hooked up. Did you change the Disc in the FMU when you went to the 24lb injectors. You are lucky that your not building any more horsepower than you are because you would be replacing head gasket each time you get to 5psi.
speedy whats your setup? Nice #s
THE FMU IS BY PASSED CAUSE OF THE BOGGING I THINK ITS THE ORIGINAL ONE IT CAME WITH .WY DO I CHANGE THE DISC AND WHAT WILL IT DO THANKS
mani, the reason your running so rich with the FMU is because the unit is calibrated for 19lb injectors which needs more fuel than a 24lb injector but you will need that additional fuel when in boost so order the 24lb disc from Paxton or you probably can find one for sale used on this or another board.
crazyhorse88. Stock short block 140k miles, ported E7 heads, Interceptor II(custom), 42lb injectors, 80mm MAS, 70mm TB, Cobra Intake, 3.08 gears, MSD Digital 6Plus. 255lph internal.
I granny shift at 6500-6800 rpm, stock T-5 140k miles, street 265x50-15 Pep Boy specials on Welds. 2.20+ 60ft and goes thru the traps in 3rd at 6500 rpm and turn between 11.60-11.89. My car makes 450is rwhp at 8psi and 480is at 10psi. I have driven the car with my 14psi pulley and rev the car at 3,000rpm drop the clutch in 3rd totally destroy the tires and ran 12.27 at 112mph to win a bet at the track(With the weight of a passenger to validate the rpm). My car could easily run with slicks and the safety equipment(bell housing-I like my feet) and 3.73 gears in the low 10's. But I drive the car 7 months a year and put 20k miles and still get 22.5 on the freeway.
WHATS IT CALLED EXAC AND WHAT WOULD IT COST AND WHATS THE BENEFIT OF HAVING IT MORE POWER OR SAFER
Hey Speedy what kind of Blower do you have? Can my sn-92 make that kind of power? Alot of people are telling me that my sn-92 makes 100hp but takes 50hp to turn it is this true? Thanks For all the info
I have the VR4 racing ball drive. All superchargers take a lot of energy to turn and the ball drive takes no more than the others. People think because it is harder to turn when your using your hand that it takes more power to generate power. When you are moving air and your spinning the impeller all the air is force against the impeller and that is the same and usually takes the same amount of force to rotate. Back in the early 90's testing was done in every Ford type magazine and even in my Chevy magazines to see what supercharger built more power at the same boost level and the SN Paxton always beat the Vortech 'A' at the same boost levels (5-6psi). Boost is not the only thing needed to build power. You need the unit to push enough volumn and that is done by housing size and impeller design. In the 17 years I have used the Paxton I always here the same thing when people switch from the SN to another brand or even to the Novi1000 and the Novi2000 when they switched from the VR4, that the Paxton always built more power and drives much better with the same setup. You can look around at all the BBS and do a search and you will see it, people asking how come the new supercharger has less power than the old ball drive . The reason is the SN builds more CFM of air at the same boost levels. The real numbers on a SN series is about 800 cfm at 6psi below 6k rpm and I have seen this tested in person. My VR4 at 5400 rpm and 15.2psi was pushing 1376 cfm and this was also on a blower test dyno back in '94 when I had it tested after the billit impeller was completed. When the Novi2000 came out and everyone was using the VR4 most teams lost power for many months till they could change combinations and after a season of racing still matched power numbers of the VR4 and some teams went back to the VR4 to even finish the season because the VR4 ran cooler and built better numbers. I collect magazines and if you raced Renegade you ran a VR4. The SN always gets a bad rap because if it is over revved it takes out the main shaft and the balls in the drive. Well for under $300 you can repair these units yourself and it takes about 1 hour to take apart and put the new internals in and you don't need a press or any special tools. I see on these boards all the time that the Novi or Procharger or Vortechs are leaking or the bearings are going out. You must send them in and if not under warranty spend $700+ plus shipping and weeks(months) to get them repaired and they won't sell you the parts outright to do yourself if you have the means. I have 3- VR4's and combined I have over 150k miles on them and have only purchased new rear seals twice at $55 including shipping and $450 for one master rebuild kit excluding bearings. I have never replaced a bearing yet and that is also because the design does not put a rear load on the front bearing since the SN is a two shaft design.
If I ever did purchase another Supercharger it would be a Procharger because of the RPM limits but I can even use the power I have now safely because it is my daily driver and at the track it is 'ET' racing anyways so I dial in at a 12.50 so that I don't need all the safety equipment (Roll Bar) and at my IHRA track you can run till 11.49 so I always dial in at 12.00 and usually break out anyways. Now that I am off my soap box yes it takes horsepower to make horsepower and it is closer to about 30hp to make 5psi of boost and the more force(boost) you make the more horsepower it takes.
My VR4 dyno sheet back when mine was tested at max boost 15 psi my supercharger was using 98hp or close to it.
Mani, FMU Calibration Disc.
Increases fuel pressure in proportion to boost pressure.
Recalibration kits available separately.
P/N 6Z170-010 Recalibration Kit, 6:1
P/N 6Z170-015 Recalibration Kit, 4:1
P/N 6Z170-020 Recalibration Kit, 8:1
P/N 6Z170-030 Recalibration Kit, 12:1
P/N 6Z170-040 Recalibration Kit, 10:1
P/N 6Z170-050 Recalibration Kit, 3:1
P/N 6Z170-060 Recalibration Kit, 7:1
P/N 6Z270-010 Recalibration Kit, Includes 4:1, 6:1, 8:1, 10:1, and 12:1
http://www.vortechsuperchargers.com/.../fuel_fmu.html
Now I forget which one is for which injectors so go to the site above and it should be listed someplace.
speedy what are the limits of my sn-92? I have a stock pulley on there now and I want more boost but dont want to kill it, what do you recomend?Thank you for all your Help I really needed it! Everyone is saying to get rid of my sn and get a gear-drive but i think I will get it to the track and see how it goes!
speedy you know your **** lol what fmu would i need i have the stock one that comes with the sn2000 but it bogged at 4400 to 5500 rpm so the mec bypassed it then the car didnt bog. should i leave it . or put the right one. I have 24 pound injectors now, always had 255 fuel pump. which fmu do i need for 24 pound injectors. thanks
mani, I will try to find the Disc ratio for you I just have not used a FMU for many years. At your horsepower level you could be safe with 30lb injectors but with 24lb injectors you are or will go lean at the top end under full boost. I think you can find the ratio on the link I added above but I will check on it for you. Do you also have the correct MAS meter for the 24lb injectors.
crazyhorse88, A 3.75" pulley on the supercharger will gain 2psi and should put you at 8psi. The air temperature should still be ok but you need enough fuel volumn to keep up. I don't remember your fuel pump size but a 255lph will be ok or if you have a 190lph or smaller get a secondary pump but dropping the tank and installing the 255lph is much cheaper. Just make sure you change your fluid every 3000 miles and if you do to the track I always change my fluid when I am done or every 1500 miles. Type 'F' is cheap so change often and you will keep the small internal shaft alive for a long time.
yes i have a mass air thats off a 93 cobra and its cali for 24 pound injectors
Nice I have a botle of paxtrac fluid I am going to use along with my 255 fuel pump, with gt-40 intake, edelbrock heads(out of the box) 1.7 rr, 65mm tB, 73mass air, stock cam and lower with 8psi 24#injectors and fmu for 24#s and msd 6btm, where should I be HP ? 1/4? with drag radials I know its hard to say based on every car and driver is diffrent but I just wanted to get a general idea, Thanks so much!
mani, You need to ask some questions in the general question section of this board because I was thinking the MASS on a Cobra was 19lb calibrated and the Cobra computer makes it think it is 24lb. If so of course your are running rich and costing power that way also
crazyhorse88, I would guess 108-110 mph. 13.20 1/4
well the mass air looks bigger then the other stock one and the mec sais that the black board that srews on to it is for 24 pound injectors
Wow I was thinking alot faster than that! I ran low 14s with gears and exhaust! I since did heads, intake,headers,injectors,fuel pump,roller rockers, and supercharger! if this charger dont get me in the low 12s I am planning on a 14# procharger, do you think that the charger would be holding back the 1/4mile times or something else? Thanks
Get 42lb injectors ,trash the FMU, trash BTM and get a tuning system. (PMS,Tweecer Etc.)
Then I think you would be close to the lower 12's with 8psi.
crazy horse a car thats in the 108 -112 is in the 12s it all about how you hookup thats the most important if you have a tire then i guarantee 12.30 to 12.90 if you can keep your 60 foot under 1.9 atleast
wow this is great, to see some #'s and combs for the sn blowers. I have an sn2000 with upgraded impellar and the tranny cooler system. I ran last year at the local drag strip and got 12.3 @ 109mph 1.71 60' at 5lbs boost. (missfire issues) anyways i have a little gadget i picked up from a guy on here that allows me to change my fmu ratio, without changing disc. It works great. I have a 3.75 pulley sitting on my shelf since it over turned my sn93 i had and burned it out.
Q's 1 : can i use the 3.75 with the new sn2000 i have with out any probelms.
Q's 2: what f-150 crank pulleys are people use. (the 7" one) i keep reading about.