New Guy, inital install question on sn2000

**Scribbles** · 08-26-2008, 10:29 PM

Wow, I am finally registered, YAY... ok down to buisnes,

I recently picked up a used, sn2000 kit for a Chevy TPI motor, I am running an 88, GTA, 350. The kit is mostly complete, but is missing the water/meth injection stuff. I purchased a manual from crund racing, so I have that. But I was able to get a better manual from a member a 3rd gen.org. My question is it safe to install the unit without a secondary fuel pump, FMU (did not come on stock kit) and water/meth injection. I am running the 6 rib pulleys so I will probley have some bet slip. I have the stuff to do tuning, so I will start to do that after install, and will not be racing till I get it tuned, but I don't want to hurt the motor, this is not a daily driver it only get's maybe 100-200 miles a month. Also did the sn2000 get the upgraded impeller, because mine looks very curved at the tips?

Thanks for the help. Scrib

**Formulalt1** · 08-26-2008, 11:33 PM

I installed a walbro 255lph in my Fbody when I added the supercharger but running 6 lb's or under you should be fine with the stock pump and a set of 30 - 36 lb injectors (assuming you get a decent tune).

**pavement pounde** · 08-28-2008, 03:12 PM

You need some form of extra fuel when you are in boost, you do not want detonation with your stock bottomend, I would at least go with a bigger intank fuelpump or extra inline pump.
The SN2000 should have the newer curved impeller.

**Scribbles** · 08-28-2008, 05:11 PM

my thought was an inline summet brand (cheap) to boost the fuel pressure. what about a fmu, seems easy to tune, just $200 - $300 sucks.

**Scribbles** · 08-28-2008, 05:15 PM

if i use a fmu and second fuel pump, can i get away with my stock injectors? 22lbs. the kit from paxton never used any of this stuff, why? i like the paxton becuse of the boost curve, and quiet operation, but procharger comes with all the stuff nessasary, pump exe.

**Scribbles** · 08-28-2008, 05:17 PM

and before any asks, i will not race this car i just want a toy, 300-350hp at the wheels i will be happy.

***speedytang*** · 08-28-2008, 11:10 PM

Your going to need additional fuel and at 6psi your going to need at least 40psi of additional pressure. A FMU is your best cheap option. If your fuel pump is healthy you will be safe at 5-6psi but if your voltage drops to the pump your going to be really lean at the time of the voltage drop.

**Scribbles** · 08-28-2008, 11:12 PM

can i get a normal fmu, or shoud i bite the bullet and get the super fmu?

**F=MA** · 08-29-2008, 10:01 AM

Get the normal one. Try ebay, people pretty much give these things away. I've had no problem running one on my 88 speed density mustang with stock 19 lb injectors. It makes 320 horse with that 5 lb setup, drag strip verified.

F=MA

**pavement pounde** · 08-29-2008, 12:14 PM

I would do what these guys say.
Paxton originally put a extra inline fuelpump or replacement intank pump and a spacer with 2 injectors to put under the tbi in just about all superchargerkits, al least with the GM en Dodge kits.

***speedytang*** · 08-29-2008, 03:38 PM

I have a used unit with lines I will sell for $35.00 shipped. It is a original Paxton unit.

**Scribbles** · 08-29-2008, 06:31 PM

sold.

i will send you a email tonight.

**Scribbles** · 08-29-2008, 06:35 PM

I can get an inline pump from summit for like $90 I am running tpi, so it is direct port injection, with the FMU and second pump I think I am good. Any ideas on a cheap water injection system. I have the injector that came with the intake tract but nothing else. Can I covert my windshield washer tank and pump to do it?

i am also running maf, witch is much more forgiving on earley GM efi, with tune and fuel curve.