I have a Turbo XS Dual Stage Boost Controler. I have the switch hooked up to the cigaretter light because the switch (from 11psi to 16psi) is right by the CL and it only works when the car is on, made sense IMO. BUT, sometimes under heavy boost the fuse blows, or should i say, it blows quite a bit.

how does anyone else have theirs hooked up?

So step the fuse up another 5A. What is the Cig lighter, 10A?

It sounds to me that you have a short. I have almost all my gauges, turbo timer, rev/speed hooked to that same line and ive never blown a fuse.

That's a flawed eletrical system.

You can make the fuse bigger to a point, but you have to be careful. When you add half a dozen gauges, boost controllers, and whatnot you will be drawing too much current down that little cig. lighter wire. When you pull more current through a wire than it can handle, the voltage will drop, and guess what happens then? Things start getting screwey. Gauges become inaccurate, especially EGT gauges. Sure, these things have regulators internally, but they can only compensate so much. Personally, I'd want my EGT gauge to be as accurate as possible.

Hook up a wire directly to the positive terminal of the battery. Some 12-14 gauge wire is all you will need. I used some heavy speaker wire laying around. Stick a fuse (maybe 30-40 amps?) in there as close to the battery as possible, then run the +12 to a relay that is normally open, but closes once the key on power turns on. Now, you have a decent eletrical system.

Originally posted by ner947
That's a flawed eletrical system. You can make the fuse bigger to a point, but you have to be careful. When you add half a dozen gauges, boost controllers, and whatnot you will be drawing too much current down that little cig. lighter wire. When you pull more current through a wire than it can handle, the voltage will drop, and guess what happens then? Things start getting screwey. Gauges become inaccurate, especially EGT gauges. Sure, these things have regulators internally, but they can only compensate so much. Personally, I'd want my EGT gauge to be as accurate as possible. Hook up a wire directly to the positive terminal of the battery. Some 12-14 gauge wire is all you will need. I used some heavy speaker wire laying around. Stick a fuse (maybe 30-40 amps?) in there as close to the battery as possible, then run the +12 to a relay that is normally open, but closes once the key on power turns on. Now, you have a decent eletrical system.

The fuse in there is a 20...hey thanks for the tip, much appreciated! :thumbsup

Not trying to get off the subject, but I have the same MBC as you do and I was wondering how you prevent boost spikes with that thing. My wastegate acculator is set for 5psi. I turned the first stage up to 6psi, but when I step on it it spikes to like 8psi or so and then settles to 6 again. I would like to run about 8-9psi but with the spikes I'm not turning it up anymore until I get this sorted out.

Mine spikes at 16-17psi then settles at about 15. I dont know what the problem is. If you find anythign out let me know

http://forums.2gnt.com/dcboard.php?az=show_mesg&forum=8&topic_id=69834&mesg_id=69834&listing_type=search

The link XtremeRS posted about the APR.

I just tried this a few minutes ago. It didn't work for me. I turned the boost up a full turn and it didn't increase on the guage anyway, but I thought it had a little more go to it, and I was running leaner than normal. I unhooked everything and might try again someday. I don't know what happened. I don't have time to mess with it anymore today.

good link...I thought maybe becuase I'm still running the stock fuel system. With it working like brand new i can only support around 16.5psi. What did you try though? I read most of the post's and came up with that it might be a bad boost controller.

This:

Whooo hooo! I think I fixed it..with a little internet help and searching..Somone on a Saab forum figured out a way to prevent boost spikes or "overshooting". Basically, you use an adjustable Air Pressure Regulator, getting its pressure input from the compressor. You use manifold pressure for the MBC inlet. Then, on both the APR and MBC outlets, you tee them togheter and run to the wastegate. So what does this do? Well you set the APR to "prime" the wastegate with a few psi of air pressure, whenever there is boost. Then, when the MBC's ball/spring mechanism is lifted off its seat at your set pressure, it makes the wastegate much, much more responsive. The spike is caused by a delay really. Since this turbo spools so quickly, esp using a MBC, the MBC cannot react fast enough to open the wastegate to not get any overshoots in pressure. Now, with the wastegate being slightly pressurized, the time it takes to open it, is greatly reduced, and no spikes. I tried it out tonight, and preliminary testing reveals it works, and works quite well. I didn't have much time to play with it, but a little tweeking gave excellent results. This is a very good read, if anyone wants to get more info on the setup. Its called a "MBC Anticipator"

http://www.saabnet.com/tsn/bb/9-3/?bID=73160

http://www.saabnet.com/tsn/bb/9-3/index.html?bID=69576

http://www.saabnet.com/tsn/bb/9-3/index.html?bID=84683