In need of tuning

[TRICK PONY]

I have a 90 5.0, it has a GT 40 intake, 70mm throttle body, 6psi powerdyne supercharger, shortie headers and flowmaster exhaust. I also have the accel 300 plus ignition systerm but the rpm retard shuts me down at 4500 so I disconnected it. I have an idle problem that roams from 800rpm all the way to around 1500 rpm. I would love to know how to fix it and a quick estimate of what horsepower should be coming out of it with these mods.

[exgmguy]

Are you using a bypass valve? Without one you usually get idle problems like that.

[TRICK PONY]

Are you using a bypass valve? Without one you usually get idle problems like that.

I just looked on powerdyne's website for a bypass valve, it is 170 bucks. I really hate this company. Is there anyone else I can get one from or maybe build one myself. I got the supercharger and it was broke, the bearings were seized and the belt was chewed up. I got bearings and pressed them in. All I needed was a belt. Powerdyne wouldn't sell me one and went a step further telling me that no one else makes them and that they are patented for their superchargers only. Thank god for the internet. I got all the belts I will ever need for $2.97 each. Know anyone needing belts or bearings? I spent about 65 bucks rebuilding it. Powerdyne's estimate for doing the 30 min belt and bearing swap was over $500-plus shipping and handling. I really hate that company.

[regattacoupe]

Do a search for bypass on here and it will help you alot! Congrats for rebuilding the blower yourself!! I doubt you'll have $40 in the bypass valve when it is all said and done and it might make those internal belts last longer.

[exgmguy]

I bought one locally from a Saab dealership. Tons of factory Turbo cars use the same black plastic Bosch bypass valve. I think it might have been $40 or so, then you will just need some hose, clamps, and maybe a 90 degree elbow, all available locally.
Does your discharge tube have provisions for a bypass?
www.superchargersonline.com also sells the bypass valves for a lot less than $170.

I needed to replace the small cog gear that the belt rides on. Powerdyne would not sell me one either. Right now I am having a machinist I know make me one instead. (without the holes in it so it should make a little noise now)