Supercharger no power

[88t.birdsc]

Hello, I bought an 88 tbird with a 5.0 s.o. I wanted to get the single best power added I could find at a good price. I didn't want to have to keep changing other parts for little gain. I saw a sn93 charger on ebay with a cog setup and I bought it. The guy made it sound like it was something special. When I got it I found it was missing several necessary brackets and the charger pulley was a 3 groove and had iroc stamped on it. I wanted to get it installed and was told to call Craig at Paradise. When I spoke to him he said he has seen people get ripped on ebay all the time and proceeded to talk me into buying one of his kits since the missing brackets were going to be expensive. I installed the charger and drove the car and was very disappointed, the vehicle seemed no different. I thought the vehicle was not getting into the boost so I installed an Auburn 3.73 posi and thought that would get it. Much to my suprise it didn't either. I took a former mechanic for a ride in it and he laughed and said it seemed almost slower with the charger. We checked fuel pressure 35psi at idle and 60psi at wot when the fmu "line locks" the return. Boost rose about 1 psi ever 1000rpm to psi at 6000. I called Paradise and told him and he said I had no motor. By this time I'm totally frustrated and bought a 125 shot of the juice. One guy on the web who swears by centrifugal's said he seen motors blow with that set up. He said 255lph in tank and t-rex pumps and disks in the fmu are needed 1st. I decided to do a so to ho conversion to see what would happen and increase the fuel pump since it felt like it was starving for fuel. The vehicle now has e7 heads, inj. and induction and a 255 fuel pump. I figure this time for sure. Now I drive it and it bogs and hesitates, misses, intake pops/backfires and engine wont rev past 4000 and only to 4000 for a second or two then bogs down. fuel pressure does not hold after turning the key off(bleeds down) bbk adj. reg. shows 40-45 psi and no boost. Fuel pressure will rise a little when I blow through the fmu vac. line. I decide to take the supercharger off and it runs half decent. I don't know why? Still not enough fuel? Maybe bad fmu? Maybe the supercharger is bad now? I may have 500+miles on it maybe a little more. I guess I will put the belt on tomorrow and see if the charger blows my hand off the outlet. I feel like I got hooked twice. I never called the blower dealer back because he will probably tell me I have to spend more money. I began the project wanting the single best bolt on power adder. Maybe the juice is the answer. My friend says, "You should have got the Kenne Bell Godzilla."

[speedytang]

So you are seeing boost Correct?
Nothing after 4000rpm is because your blowing out spark. Gap plugs to .032.
Have you verified that the FMU works and is set for 19lb injectors?
Is this car still SD(Speed Density) if so did you put a check valve between the intake and the Map sensor on the firewall?
We will start with that for now. You will feel 75hp if everything is correct.

[F=MA]

Geez, you are a parts man's wet dream. Every time you have a little problem you throw huge money at another part. This isn't rocket surgery here. If the charger is spinning and not slipping, if the fuel pressure's rising high enough, if the ignition and timing are right and in good order, it'll rip like a raped ape. Go back to what you did, because I can almost guarantee this is a case of human error, probably many human errors.

Get the motor running right not, half-decent, before you stress it with the supercharger. Did you check the heads were flat, they had no cracks, the valvesprings were ok, the installed heights were correct, the piston-to-valve clearance was alright, the cam was degreed, the timing chain is tight, all the vac ports are hooked up, the ECM is working , the grounds are solid, etc.
These are all required work when doing the upgrade to the motor you describe.

Here's what I think you did, based on your post. Someone told you your motor was shitty because it was S.O. and, they just happened to have a pile of old HO stuff lying around they'd give you for a good price. You grabbed it impulsively, slapped it on the motor and fired it up w/o checking anything. Am I substantially wrong, tell me I am, please.

F=MA

[88t.birdsc]

I appologize for the rant, things are far better now than my last post. Charger is putting out boost and vehicle is running a lot better. The check valve and fmu were both sticking. I couldn't get enough fuel into it and it was most likely way too lean. If at all possible I could use some additional coaching to get a good tune on it. Needless to say, a new post is needed.

Thank you
Mike

[Dirk Diggler]

My first thought was to check your plugs! Second, a compression test, Third, leak down test, and a wide band test. these tests can tell you what's really going on in times of confusion............not always, but they do put the light at the end of the tunnel;)

[DSBLK93GT]

DYNO...wideband...

[88t.birdsc]

Been away from the board awhile and have dug up my 1st post with qtr. mile times now. I've been working alot and the car had just sat. With the times hopefully we will know what will works and what doesn't. Next time I will run and tune without the charger before I stress the motor anymore. Getting the motor right on will help me get the most use and enjoyment out of the charger. Thanks again for the advise and I should be able to work on the car more. I will post the fix and then the parts that help. :)

[88t.birdsc]

fyi: 16.4sec @87mph 2.51@60'
files won't upload

[F=MA]

Wow...that IS slow. Is that with the charger on? This thing must take 18 sec blower off . Sheeyat, my 4.3 litre Chevy G10 Van is faster than that:happy: .

You're absolutely right though. Get the motor's house in order first, then charge it.

F=MA