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Is it possible for the motor to be 180 degrees out..?

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Old 11-20-2019 | 02:43 PM
  #16  
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Closing the loop on this:

Originally Posted by Shawn Stanford
It was the injector pulse I was concerned about, and I don't really understand why more than one injector would fire at once.

The injectors in the car are "batch fired", where all the nozzles are activated at the same time. "Modern" cars are more likely to have sequential injection, where the nozzle is opened just as the intake valve(s) underneath it open. In our batch-injection cars, fuel has a small chance of spraying into an open intake port on any given engine rotation. The rest of the time, the fuel ends up condensing on the walls of the intake and inlet port. It then gets to evaporate into the air flowing through the port when the intake valve(s) actually open. To maintain sufficient fuel content to support proper combustion, a little extra fuel must be added. The problem is much more acute when the engine and intake are cold. Regardless, we have what we have as far as the batch-fired injection.

There are some aftermarket injection systems that support sequential injection, and you can get better higher-capacity nozzles to go with them since they also support more precise opening times. At some point there will be a plug-and-play option that uses a new engine wiring harness and a few more sensors. The installed costs of one of those systems can easily exceed the prices of the used-car market value of many 928 examples. For those who treasure originality, the differences in performance and fuel economy won't appeal enough to make an injection system upgrade desirable.
Old 11-20-2019 | 05:28 PM
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Originally Posted by Kiln_Red
Follow doc's suggestion to verify compression and report back. As others have said, you can't end up 180° off (cam timing) without making a concerted effort to do so.
I don't know how much more of my time this is going to get. If there was a chance that turning the crank 180 would get the car running, I might give it a shot. However, this car already has another engine waiting, and I have more than enough projects demanding my scarce time.

Originally Posted by dr bob
Closing the loop on this: ...snip... Regardless, we have what we have as far as the batch-fired injection.
Got it. Thanks. That's f*ing crazy; it sounds like a more complex throttle-body injection.
Old 11-21-2019 | 12:00 PM
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The issue has nothing to do with 180 crank degrees- the issue is whether your distributor can be mounted 180 camshaft degrees out of synch. As I stated in an earlier post I have no idea if this is possible on a 928 unit so my expectation is that some kind soul will confirm whether this is possible or not. For sure it is nothing to do with fuel injection.
Old 11-21-2019 | 12:29 PM
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Originally Posted by FredR
The issue has nothing to do with 180 crank degrees- the issue is whether your distributor can be mounted 180 camshaft degrees out of synch. As I stated in an earlier post I have no idea if this is possible on a 928 unit so my expectation is that some kind soul will confirm whether this is possible or not. For sure it is nothing to do with fuel injection.
No distributor on 32V cars.

Yes, it is possible to set the distributor 180° out in a 16V engine.
Old 11-21-2019 | 12:47 PM
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Originally Posted by Kiln_Red
No distributor on 32V cars.

Yes, it is possible to set the distributor 180° out in a 16V engine.
It is confusing as to what motor we are talking about here. Initially I thought we were talking about a 16V motor but that was Shawn's own car and he was talking about that of "a friend". Then someone said it was a 32V and then another post said it was a 16V.
If it is a 32V motor kitted with EZF then not possible unless one deliberately reassigned the leads on the two distributors and I think we can safely dismiss that possibility.
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Old 11-21-2019 | 01:22 PM
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Originally Posted by Kiln_Red
No distributor on 32V cars.

Yes, it is possible to set the distributor 180° out in a 16V engine.
i assume you mean the rotor ? because the distributor bolt has to go in ….
Old 11-21-2019 | 10:21 PM
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Working on someone else’s car....
1st rule of life; NO GOOD DEED GOES UNPUNISHED



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