Check my mods and tell me if you can what my SN92 redline would be on my engine? How much does the 10 pulley cost and where can I find it? thanks ------------------ 91 Formula 1LE 1 of 46 305 TPI 5speed 1LE/G92/WS6 Paxton SN92 supercharger, Ford SVO 24#injectors, Crane AFPR,SLP airfoil, ported/polished plenum, March alt. pulley,Crane Gold 1.6rrs,MSD coil,MSD6AL (5400rpm limit),Holley 9mm wires,Ac delco R43ts plugs,custom chip,Bosch O2sensor,SLP 1 5/8" headers,SLP catback,shortened shifter,3:73s w/Auburn posi,180* t-stat,JET 195* fan switch, Macewen white face gauges, Autometer gauges, Zoom hi-performance clutch.

From the reading that I have done on SN-92's.. putting a 10-lb pulley on one that has not been updated will probably not be too good for the thing.. as they are prone to fail if you spin them too fast. If you get it updated, then I hear it's ok.

If you check out corral.net, on the message boards they talk about places where you can get any pulley you need custom made.

I heard getting them from paxton is expensive.. over $100.

What's your experience with your SN-92 so far.. how long have you had it, have you re-built it? I am trying to find out what people think of this supercharger.

This blower is around 8 years old with no rebuilds. Only thing done to it was replacement of seals. It has over 80,000 miles on it and performs flawlessly. Knock on wood

That's very encouraging.. what did you do to fix your seals? Did paxton do it? Did they charge a lot?

From what I have heard about the SN series is that past ~57000 rpm (if i remember correctly) they will have trouble if they are not upgraded.. a 10lb pulley will make you go past that. I personally wouldn't mess with a good thing. Wait until you update it. You can find out a lot about the SN series and different pulleys on places like camaroz28.com and corral.net..




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89GTA5spd – Came: Completely Stock w/ 3.42’s, rear disks, dual cats, LB9 305, T5, bad paint & interior. I did: Conical K&N w/cust piping, TPIS Airfoil, Ported Plenum/Runners, TB By-pass, Home Made AFPR, MSD Cap/Rotor, Jet Fan Switch, 180 T-stat, , Flowmaster 3” Cat-back, Eibach 1” Drop, KYB’s, Hotchkis STB, BFG 255 Comp T/A’s, NOS TPI (custom) Kit , Sony CD, Orion Amp, Fosgate 10’s, 1991 GTA interior, new paint. I have but have yet to put on: Alston Bolt on SFC’s, Paxton SN-92. Soon: Mallory Hyfire, Autometer Phantom Elec. FP guage, N20 Guage, Boost Guage, Hobbes Switch, Bottle Blanket. Not So Soon: alum headded L98. Always a work in progress..

Well I just picked the blower up from a guy who lives near me. It was on his stock 91 305 TPI Z28 slp package car. Get this, with 24# injectors and prom work he ran a 11.6@116mph at Cecil County.

Anyway, the seals were changed 500miles ago and the paxton went through a yearly inspection. I don't know the costs because he was the one who got the seals changed. By the way, this blower never had an oil cooler. I just hope I have the same luck the previous owner did. Oh well. If it breaks I'll send it in to be rebuilt. No big deal.

I'm not going to get the pulley. I imagine my redline will be drastically reduced with the addition of the above.

[This message has been edited by theformula (edited April 16, 2001).]

Those are some incredible numbers for a 305. Right now I have a pretty much stock car that I have gotten to run 14.8 w/ some awful 60fts. I think w/ better 60fts I could get 14.6 no problem.

This weekend I plan on running a 50 or 75 shot of N20 to see what times I will get with that.

Then I am planning on installing the paxton and running no n20 or a very small shot.

I want to see what I can do w/ a 305 and bolt ons only and through the stock manifolds.

Then maybe some slp runners and a set of headers. I am also starting to think about burning my own proms. I think that the 305 can do more than people think...

Please post some times with your car when you get them, they would be very interesting.

I think willies low 12 times with his 305 is proof that a 383 isn't always the easiest or best solution.

My personal experience with SN-92 units tells me that the unit would be likely to fail shortly after the installation of the pulley. Sorry - just the shortcomings of a planetary ball drive vs. a gear drive. Hope this helps.

Ryan,

Keep in mind that your pulley size causes the blower to redline (38,000 rpm) at approximately 5,500 engine rpm. That being said, if you were to increase blower speed by installing a smaller blower pulley, you will NOT produce any more boost because you cannot exceed blower rpm. All that will result is you will lower the engine's rpm's range because of a faster spinning blower.

As for a Paxton's yearly check.... I know that's what the previous owner told you. I owned a Paxton SN series blower for almost three years. First, it was an SN92 that I bought new. It did not have a high flow impeller. Then I had a high flow impeller installed. Paxton told me that they would not just install it, that a rebuild is necessary because of the increased pressure the new impeller would impart on the planetary ball drive -- an increase of 41 percent. I had it done.

Less than one year later, it needed a rebuild. Instead of paying $550 for a rebuild, I decided to trade it in on a new SN2000 for $800. At that time, I was leary of this product. The new SN2000 came with a six month warranty.

I mention all this for one reason. When I bought the SN2000, I stated that I would send it back before my warranty period expired to have it inspected. Paxton told me NOT to do this -- that they will not take apart a blower to inspect it UNLESS I had reason to suspect something was wrong. In a nutshell, Paxton does not (and will not) do "inspections" on their planetary ball drive superchargers. I hope I'm wrong, but I have a feeling the guy you bought it from was feeding you a line when he stated your blower has had yearly inspections.

Willie

[This message has been edited by Willie (edited April 23, 2001).]

Just for your info, here is the forumula to figure out the rpm of you supercharger;
dia of crank pulley \ dia. s/c pulley X 4.4 X rpm = RPM of supercharger.

6/4 X 4.4 X 5500rpm = 36300rpms. My paxton max rpm is 38000rpms. You can go a little higher due to the 10% belt slippiage.

I think you're probably right Willie. Well I did call Paxton and give them the serial number and they said it was never rebuilt. Oh well. At least he told the truth about that one.

Thanks for the formula craiger