overboost cut on 1990 spg lh 2.4

[saab900turboguy]

Just got a chip from Jak Stoll and he tells me he programmed the overboost cutoff almoat completely gone but not all the way. I need to defeat it the rest. The research I did says two things. 1 join the bwon and brown white wires together at the relay behind the ecu or join the vacuum lines. And the other is wiring a resistor into the yellow wire of the amm.

Soo what ia the proper way to defeat it on my car?

[dmgb5]

Why are you deliberately trying to bypass an APC safety feature?

[saab900turboguy]

Its no longer a safety feature but a speed bump in my quest for power. I dont knock and I have all the support I need to start banging 25 psi at 7k rpm.

[socal1200r]

Originally Posted by saab900turboguy

Its no longer a safety feature but a speed bump in my quest for power. I dont knock and I have all the support I need to start banging 25 psi at 7k rpm.

25 psi?! Here, let me pull the pin on that grenade, and just sit back and wait for the inevitable...

[B202NUT]

Originally Posted by saab900turboguy

Its no longer a safety feature but a speed bump in my quest for power. I dont knock and I have all the support I need to start banging 25 psi at 7k rpm.

'

Buy a Porsche.

[anjum]

You can either take it out of play by joining the wires together, or unplugging and bunging up the vacuum tube.
Or you could increase where the cut out kicks in by winding the screw in the centre, use a pressure pump and gauge and a meter to see when the switch operates.

[88saab900s]

hope your transmission is built... or you will be picking parts off the road putting numbers like that out

[900t]

Does that car even have that thing? I thought it was only on like 1988 and older ones.

[saab900turboguy]

I dont know if it has it or not. That is why im asking. And yes tranny is peened and cryotreated with steal synchros. Its a bit notchy but it works well. And If I wanted a Porsche I would have bought one. I bought an STI for reliability and power, and if it breaks great gives me something to do.

[B202NUT]

Originally Posted by saab900turboguy

I dont know if it has it or not. That is why im asking. And yes tranny is peened and cryotreated with steal synchros. Its a bit notchy but it works well. And If I wanted a Porsche I would have bought one. I bought an STI for reliability and power, and if it breaks great gives me something to do.

enjoy! do you take it to the track? I like reading about you guys and all your power. Shows these cars have some guts but I sincerely appreciate the stock versions. To each there own.

I really hope your on a track though. Burning rubber from stop to stop, stealing a moment when you think the man is not lurking around the corner and trying to be the first off line at a traffic light is a bit adolescent...

God I hope your exhaust is quiet; see where this goes. Everything in moderation has always been good advise for me...

Cheers and good luck,,,

my point in suggesting a Porsche was at least you'll have a car that was designed for the type of power your seeking; buit then affordability comes in question. Surely if you could afford one it would make more sense than straining a weak gear box to the hilt.

Cant fit a peg into a square hole type thing ...

I know jack nothing about modifying these cars. I just sit back and read albout all you guys Vroooooom, screeeched; Damn!

Seems like no one learns though; eveyr new guy comes along tries to run 400 horses in stable designed for about 200 max... oh well,,

[Krizzie]

Horses aren't really the problem it's the Torque that kills the Gearbox.. If you let a lot of torque come in too fast, you just pull everything apart.

I've had a ride in a 280hp/450nm 900 classic (Stil using oldskool APC and ignition) it went like a modern car, not really a big punch in the back when you floored it, but it went like a hot knife through butter! The tranny had more than 300.000kms on the clock and held fine (It still does)

[Saab named Jag]

Does that car even have that thing? I thought it was only on like 1988 and older ones.

I don't know Ive hit 22psi with my 89 once when I was messing with the apc and never hit the cut. I figure if it were going to hit the cut It would have done it then

[ziedoniz]

I've accidentally experimenting had 20psi on Lh2.4, nothing.

[nbndtrain]

Originally Posted by 900t

Does that car even have that thing? I thought it was only on like 1988 and older ones.

I thought LH2.4 fuel cut was all in the chip. Boost cut is through the APC.

[ludichris001]

have you considered switching to T5 or Megasquirt?

[saab900turboguy]

Yes i'm going to do T5 in the near future. I'm using an MSD BTM right now to increase timing control. It's all about finding the time to do it.