I just fully installed my paxton sn89 supercharger today. I went to test drive it and I didn't feel that much of a difference. What RPM does the supercharger kick in? Do I have to have the alcohol injection installed (tested without it)?

 

How much boost is it making? Probably wont feel much tell past 4000rpm.

 

It should make 5-6 psi. That 4000 rpm makes sense, when I was revving the motor the silicon piece holding the tube to the throttle body popped off when I hit 4000. I have to put on a tighter clamp tomorrow and test it again.

 

Get a t-bolt clamp for that if you can.

 

Is this a basically stock 89 350? reason im asking is,Im thinking of buying a supercharger,and If you didnt feel a major diference I might just save the money.

 

This is a almost stock 305. Th only mods before the supercharger were a 350 corvette chip is in the prom and I had a gutted out airbox. Since you have a 350 you will definitely feel a difference. MY little 305 noticeably pulls a little harder, but I think I had higher expectations. I need a chip tuned to the supercharger and an airfoil, then I should free up a lot more horsepower. Right now I am afraid to go above 5000 rpm because I don't have alcohol injection or my intercooler hooked up.

 

How is it adding more fuel? fmu?

 

This old paxton SN 89 kit didn't require a separate fmu unit. This kit was only meant for 5 psi.

 

Here is the verdict on that paxton sn89.it kicks in at 2000 rpm. The catch is that I only feel it pulling big when the supercharger is cool. When The engine temp goes up (supercharger is burning hot), it seems like the supercharger is weak. My solution is to hook up my intercooler ( I am waiting on 2 pieces of tubing to complete the conection). yea, I am running an intercooler with a sn paxton supercharger. It was either that or water/alcohol injection.

 

paxton is poop. Buy a vortech or procharger and you'll feel it.

-- Joe

 

Dammit, the SN89 is poop, not paxton as a whole I like my paxton thank you very much!

 

paxtons do run really really hot i used to have one on my iroc 350 tpi years ago.try intercooling it that will really help,supercharger will still run hot but the boosted air will be alot cooler. all the nonintercooled centrifigul superchargers are poop today.35% increase is about all your gonna get on 5-6 psi with no cooler. when i had it i felt it was a big waste of time an money.

 

Well, all together I paid around $1000 for the supercharger and intercooler kit. $150 for the cost of installing it. After I get all the vitals hooked up right, I will pay someone (professional) to burn me a chip. I had the car backfiring when I was revving it to 4000 last night, so I think the timing needs to be adjusted now. I still have not pushed the motor past 4500 rpm because I get chills from hearing other people's experiences with the sn series paxtons after 5000 rpm. I read from other people that the bearing failures happen after 4850rpm (max rpm for the supercharger). I want to get the 3.5 in pulley ( which increases the max supercharger rpm to reduce bearing failure) but I have the 3 rib v belt kit which makes that pulley impossible to find.

 

I would but the old paxtons are the best for us who are jobless

 

its not that the paxtons are total junk, im not bashin any1 really. they do have some limitations more than others. but the main problem is heat they all run hot . vortech and the others are really no better if they are not intercooled either. hook that cooler up you will see a big difference. a stock chip will probably be ok since they keep timing in check. aftermarket chips like hypertech an jet are a no no as they advance the timing.you could get a custom one but may not even be needed at 5-7 psi.

 

plus you got a great deal.

 

People have been running superchargers for years without a intercooler with good results, I don't see it doing much on a stock car at 6psi.

BTW you really should look into getting a FMU.

 

I am using the intercooler as an alternative to the water/alcohol injection found on most non intercooled superchargers that see good results. There are some tricks to making the intercooler a much better choice. I'll look into the FMU once I have the whole system working properly.

 

they make a fluid cooler for the paxton its like 350 dollars

 

The POS SN 89 I bought just spun its bearings today. I've never went past 4500 rpm on it and it spun. I bought a refresh kit when I purchased the supercharger. I am going to "refresh" it then sell it for what I bought it for. I want more power (8-10 psi) so I am looking at a custom novi 2000 build.

 

how much did you buy it for?

 

$800 with the bracket, pulleys, paxtrac fluid, spare belts. I had to buy all the bolts and spacers from the hardware store.

 

how many mile did you put on this before it broke?,any knowledge of how many miles it hasdbefore you got it?

 

what the french toast what a gyp

 

How so? Water/alky injection cools better than an intercooler, it also doesnt steal any pressure. Its much easier to setup and generally cheaper.

 

Imo I feel that the water/alcohol injection is good for drag racing. I am setting up my car for pro touring. So I would like to take it to a raceway when done. I think I am done messing with the paxton sn supercharger. I'll be running more boost with whatever supercharger project I'll be moving onto.

 

I have a paxton on im pushing around 9 1/2 lbs, I had to throw on a procharger bov due to i kept blowing out my gasket on my throttle body, Im loving my paxton. its not intercooled, im thinking I might go that route
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I went a good 2 yrs on mine, but then again i got it replaced then 4 days later due the guy that installed them did a bad job and forgot to place them in correctly, and the shaft was loose. but its been a good month now with the charger back and im loving it

 

Are you running a paxton vr4?

 

Took it apart to rebuild today and everything looked fine. I put it back on the car and it worked normally for about 20 minutes then an awful screeching noise came from the casing. I took it apart and everything seemed normal after it cooled down. Now I think it needs a oil cooler. Whenever it gets hot as hell it will squeal. I think the oil needs to be cooler, what do you think? I just put the supercharger back on and it is working normal.

 

Squeeling is not normal for the paxton's. I would inspect the internals very closely! The good news is that they are pretty easy to rebuild, cheap too. You can upgrade you impeller for about 100bucks. The modified impeller will give you 2-3.5lbs of extra boost.

I had similar issues with my paxton sn 2000. I bought it from a friend on this board and it's been a great supercharger for the money. Mine has the upgraded impeller and I get 9.5lbs of boost with no problems. Make sure you have the oil cooler as this will prolong the life of the supercharger.

When I first put my paxton on, I had the luxury of buying it from a friend who worked out all the kinks. Upgrade your fuel pump. I would suspect your backfiring is from lack of fuel. My car was running out of power @ 3500rpms, then I put a walbro 255lph pump in and now, it pulls all the way up to 6000rpms. An adjustible fuel psi regulator can help too, maybe larger injectors too. And the list will continue to grow

 

Thanks for the post Raiden, everyday I am fixing the little problems that show up. After trying to fix the squealing last night, I figured the belt was too tight and it was. I inspected the internals twice and surprisingly every thing looks fine. Yes, my car does back fire around 3000 to 4500 rpm, it sounds cool but it needs to be fixed. I guess I will have to replace the fuel pump which I believe has never been changed. Changing the fuel regulator and the injectors to 24lbs is on the to do list. Today I am going to hook up a boost gauge to make sure I am getting over 4psi of boost.

 

I think things that are a must right now are;

larger injectors
adjustible fuel pressure regulator
255lph fuel pump.

I ended up using an FMU becasue my car would peter out @ 5300rpms. I found and FMU was an easy fix to that problem. I run my FMU @ a 4/1 ratio.


Keep us informed on what happens!

 

$1000??? you do get what you pay for. Hopefully the intercooler will help. Also when adding boost you must pay attention to overall compression ratio (and octane rating), a/f mix, and ignition timing. If any of these are out of range your HP and TQ will suffer heavily.

 

a free flowing exhaust to push all that forced air in out, would help alot, if its stock right now.

 

In order to get his car working right, my above parts will get the job done. And yes, a free flowing exhaust will be a huge help, but it's not needed as of now to prevent the backfiring @ 3500-4000rpms

 

I am running a flowmaster exhaust with one cat. I hooked up the boost gauge and it hit 5psi at 4000rpm. Very happy, it will back fire slightly only when the motor is very hot. I am not running the inter cooler yet. I am waiting on a silicone 3in to 4 in coupler.

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So far the bill of materials has reached $1500 with all the add ons I keep buying. Supercharger works great after fixing all thge little problem, now I am waiting on the oil cooler. I will be buying the upgraded impeller soon.

 

Today i ended up blowing my rear main seal accelerating with the supercharger on. How serious is a blown rear main seal? Do I need to replace it immediately?