Setting fuel enrichment on overboost switch?

Brickster151 · 05-31-2004, 07:20 PM

How do I go abouts setting a Saab Overboost Switch's enrichment PSI? I know your supposed to use a air pump and a multimeter, but how do I go about doing this, and how much PSI do I know I am setting it at?

Thanks, I'm doing Terminal 11 and want to make some good numbers on the dyno tommarrow!

The Aspirator · 05-31-2004, 07:40 PM

With your multimeter set it to measure OHMs. With the switch off, no current should pass through it, but when the set boost level is reached, the contacts close and you'll get an OHM reading. Or maybe it's the other way around, depends on how you're using it. Use your bike pump to pump it up until the multimeter moves, then read that psi ammount. If your bike pump doesn't have a pressure gauge, just install a boost gauge into your vacuum line setup.

Does this make any sense at all? The exact measurement from the multimeter doesn't matter, it's just there to tell you at what PSI the contacts are closing.

T11 is kool! I'd suggest you have a light come on the dash when the T11 is activated, just so that you know it's always working. Use an LED or something... I'm using an extra volt gauge that comes on when T11 comes on.... pretty ghetto, but it works! This is on my brothers 242.

John

Brickster151 · 05-31-2004, 09:21 PM

The contacts on the overboost switch close and I get a ohm reading at about 16-17 psi, is this right?

I want it to be set at 12 cause any higher than that and I get some detonation.

The Aspirator · 06-01-2004, 01:08 AM

Sure, that sounds good. Just turn in the screw a bit. I've only seen a pic of the saab ones... gotta get my hands on a few of them soon.

John

Brickster151 · 06-01-2004, 02:40 AM

Yeah I pulled like 5 switches from the yards....

I would have gotten T11 done today, but I lost the ECU terminal I yoinked, so I'll have do wrap up this mod tommarrow between work and school, I'll post the dyno results whether or not I finsih

dl242gt · 06-01-2004, 07:10 PM

Loosening the scew lowers your boost setting. The two small screws didn't need to be adjusted. There is a common terminal and the normally open and normally closed one. Use
your meter to determine the common to normally open one. I think it's terminal 1 to 3. Then
when the preset pressure is reached the open contacts close. Mine added a really good seat of the pants power boost so these motors can really use the extra fuel at top end. The two hose fittings can act as a pass through or plug the outer one and use the switch at the end of a hose. I used it as a pass through under the dash near my stock overboost switch.
Best regards,

05-31-2004, 07:20 PM	#1
Brickster151 LH 2.2'ing it up Join Date: Dec 2002 Location: Santa Cruz, CA	Setting fuel enrichment on overboost switch? How do I go abouts setting a Saab Overboost Switch's enrichment PSI? I know your supposed to use a air pump and a multimeter, but how do I go about doing this, and how much PSI do I know I am setting it at? Thanks, I'm doing Terminal 11 and want to make some good numbers on the dyno tommarrow! __________________ - Patrick 1983 244ti SCCA ITE road race car [94' B230FT, gt3071r, t5, funstuff galore] 1979 Chevy Camaro Hobby Stock dirt track race car 1998 Dodge Ram 3500 Cummins Dually to haul ^^ 1996 850R m56 daily driver 1973 1800es restomod project I am building for my mom [b230ft, lh 2.2, 16t, t5 trans] never forget Doug Williams, Peter Gray & Matthew Dionne.

05-31-2004, 07:40 PM	#2
The Aspirator It's a girl! Join Date: Apr 2003 Location: Vinemount, Ontario CANADA	With your multimeter set it to measure OHMs. With the switch off, no current should pass through it, but when the set boost level is reached, the contacts close and you'll get an OHM reading. Or maybe it's the other way around, depends on how you're using it. Use your bike pump to pump it up until the multimeter moves, then read that psi ammount. If your bike pump doesn't have a pressure gauge, just install a boost gauge into your vacuum line setup. Does this make any sense at all? The exact measurement from the multimeter doesn't matter, it's just there to tell you at what PSI the contacts are closing. T11 is kool! I'd suggest you have a light come on the dash when the T11 is activated, just so that you know it's always working. Use an LED or something... I'm using an extra volt gauge that comes on when T11 comes on.... pretty ghetto, but it works! This is on my brothers 242. John __________________ '83 242 '95 T5R '98 S70

06-01-2004, 07:10 PM	#6
dl242gt Can play the blues Join Date: Jun 2002 Location: S NJ, a suburb of Phila.	T11 mod Loosening the scew lowers your boost setting. The two small screws didn't need to be adjusted. There is a common terminal and the normally open and normally closed one. Use your meter to determine the common to normally open one. I think it's terminal 1 to 3. Then when the preset pressure is reached the open contacts close. Mine added a really good seat of the pants power boost so these motors can really use the extra fuel at top end. The two hose fittings can act as a pass through or plug the outer one and use the switch at the end of a hose. I used it as a pass through under the dash near my stock overboost switch. Best regards, __________________ Dave, 1982 242 turbo. MVP coilover front and rear suspension. Bilstein HD. IPD 25/25 bars. 3" MVP exhaust. Cosworth Sierra hot side T3 .48 with upgraded stock .42 compressor. Ported 90+.True Track diff. Flat hood 1979 front grill Ecode park/turn lights with H4 Hella. 321k miles. Had it since 1995. 1993 245 Classic, 340k miles, enem V15. Genuine Volvo stock over the axle exhaust.

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05-31-2004, 09:21 PM	#3
Brickster151 LH 2.2'ing it up Join Date: Dec 2002 Location: Santa Cruz, CA	The contacts on the overboost switch close and I get a ohm reading at about 16-17 psi, is this right? I want it to be set at 12 cause any higher than that and I get some detonation.

06-01-2004, 01:08 AM	#4
The Aspirator It's a girl! Join Date: Apr 2003 Location: Vinemount, Ontario CANADA	Sure, that sounds good. Just turn in the screw a bit. I've only seen a pic of the saab ones... gotta get my hands on a few of them soon. John

06-01-2004, 02:40 AM	#5
Brickster151 LH 2.2'ing it up Join Date: Dec 2002 Location: Santa Cruz, CA	Yeah I pulled like 5 switches from the yards.... I would have gotten T11 done today, but I lost the ECU terminal I yoinked, so I'll have do wrap up this mod tommarrow between work and school, I'll post the dyno results whether or not I finsih