hi i have a 1992 940 with a b200f and im trying to push it for some more nasp power ive got an intake on it refreshed the fuel and spark system installed and H camshaft refreshed the valve train but its still struggling to rev up in the higher rpms. my current theory is the exhaust backpressure is holding it back at the higher rpms so I wondering if anyone had insight into how restrictive the exhaust is on this model, even if this doesnt fix my issue its something im looking into doing anyway to optimise the flow and backpressure in the system.
my other suspicion is the advance/retard mechanism which i will have a go at first obviously.
1992 940 b200f running issues
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matthew1
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I've never owned a redblock but it's not the exhaust. I've read my share of roadblock tuning posts, and that's something owners open up after a certain threshold, but it's a threshold higher than where you're at.
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1998 V70, no dash lights on
1997 850 T5 [gone] w/ MSD ignition coil, Hallman manual boost controller, injectors, R bumper, OMP strut brace
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Also -> Amazon link. Click that when you go to buy something on Amazon and MVS gets a cut!
1998 V70, no dash lights on
1997 850 T5 [gone] w/ MSD ignition coil, Hallman manual boost controller, injectors, R bumper, OMP strut brace
2004 V70 R [gone]
How to Thank someone for their post
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122sPhil
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I think in 92 the ECU controls spark advance, might be bad input from the TDC sensor?
I know nothing about 940s I once put a 240 back together and I had the felex plate on wrong and it had to be turned to the correct bolt hole.
the flex plate in a 240 or 740 has a series of holes and then a spot with no hole, thats how the engine tracks TDC.
the knock sensor is bolted to the block or head area, it is suppose to sense vibrations and if it does it communicates with the ECU to retard the timing, such as on steep hills with cheap gas. to prevent knocking caused by preignition
id check the wire to the knock sensor, maybe it was left disconnected?
I know nothing about 940s I once put a 240 back together and I had the felex plate on wrong and it had to be turned to the correct bolt hole.
the flex plate in a 240 or 740 has a series of holes and then a spot with no hole, thats how the engine tracks TDC.
the knock sensor is bolted to the block or head area, it is suppose to sense vibrations and if it does it communicates with the ECU to retard the timing, such as on steep hills with cheap gas. to prevent knocking caused by preignition
id check the wire to the knock sensor, maybe it was left disconnected?
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122sPhil
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I htink the air gap between the TDC sensor and the flex plate is 2 mm, Ive checked it using a vernier callipre, bmeasue how nmuch ot protrudes and check the lenght of the sensor and subtract to get the air gap.
I had a bent up on once I had to tweak it from underneath the car also drilled a hole for access, removed the aluminum brace for better access,, saving me from needing to remove the engine or trans to access the flex plate, what I did then was take measurements around the circumference,
the reason I had to do all that was because my flex plate got bent by someone freezing on the key, gavei t gas, drove the starter up to some crazy speed by not disenguaging it, That action blew up the starter gear. Bits followed up with the flex plate and ring gear, mashed the sensor and the flex plate up.. easy way to seriously mess up a car.
I had a bent up on once I had to tweak it from underneath the car also drilled a hole for access, removed the aluminum brace for better access,, saving me from needing to remove the engine or trans to access the flex plate, what I did then was take measurements around the circumference,
the reason I had to do all that was because my flex plate got bent by someone freezing on the key, gavei t gas, drove the starter up to some crazy speed by not disenguaging it, That action blew up the starter gear. Bits followed up with the flex plate and ring gear, mashed the sensor and the flex plate up.. easy way to seriously mess up a car.
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