Something to think about in regards to pressure differential across the injector. It is not as black and white as you might think. Most especially when the injector pintle is seated. Think of of how much actual area of the pintle is seen by manifold pressure when the pintle is SEATED and how much hind end area of the pintle is seen on the fuel rail side when SEATED. This pressure differential variable would change as the size of the injector orifice changed from small injector capacity to large injector capacity. Just a theory of mine. What do you think? I could be off base on this.
Fuel Pressure Problems
- Thread starter 1QUIK6
- Start date
These, I'm sure, don't pertain to this case, but other amperage draws to think about.
Nitrous solenoid(s). Some can have a huge draw.
Electric water pump. Huge draw.
Electric intercooler pump (liquid intercoolers).
Transmission electrical. (lockup solenoid, switches)
Line lock.
Electrical transbrake. Another huge draw.
Nitrous solenoid(s). Some can have a huge draw.
Electric water pump. Huge draw.
Electric intercooler pump (liquid intercoolers).
Transmission electrical. (lockup solenoid, switches)
Line lock.
Electrical transbrake. Another huge draw.
Just got in from a little testing.
1. Idling in D- 14.2v alt- 13.7v Scanmaster
2. (1)+ PrkLtgs- 14.0 alt- 13.5 SM
3. (2)+ (2) Clg.fans on- 13.1 alt.- 12.6 SM
4. (3)+ HeadLtgs on- 12.8 alt-12.2 SM
Track conditions would be Test 3 voltage.
As I spoolup the turbocharger & bring the rpms on up the voltage increases to around: 13.9 alt.- 13.3 SM
1. Idling in D- 14.2v alt- 13.7v Scanmaster
2. (1)+ PrkLtgs- 14.0 alt- 13.5 SM
3. (2)+ (2) Clg.fans on- 13.1 alt.- 12.6 SM
4. (3)+ HeadLtgs on- 12.8 alt-12.2 SM
Track conditions would be Test 3 voltage.
As I spoolup the turbocharger & bring the rpms on up the voltage increases to around: 13.9 alt.- 13.3 SM
I don't think that the alt. has the speed reduction pulley I have never changed out any of the pulleys. What diameter is the stock pulley supposed to be? The voltage does come up to 14.0V as I increase the engine speed off idle. It just doesn't hold at the 14.0V.
Usually it is the crank pulley that is changed out to a smaller diameter to slow down the alternator.
Keep in mind that 12.6V is a normal fully charged battery. Any reading less than 12.6V is an unhealthy battery or one needing charging. This is with car not running and no draws on the battery.
With the engine running, the voltage should always be above 12.6V. Otherwise, the battery is discharging. Expecting the charging voltage to always be 14V or above is a stretch. A normal charging voltage is 13.0 to 13.8V.
Keep in mind that 12.6V is a normal fully charged battery. Any reading less than 12.6V is an unhealthy battery or one needing charging. This is with car not running and no draws on the battery.
With the engine running, the voltage should always be above 12.6V. Otherwise, the battery is discharging. Expecting the charging voltage to always be 14V or above is a stretch. A normal charging voltage is 13.0 to 13.8V.
Been busy with the GN. First of all, I decided to purchase the 200A alt. kit from TurboBuicks.com & a volt booster from Casper’s. I just didn't care for how the alternator was acting. I installed on Friday & tested Sunday evening. Wow, with C16 I set the boost at 24# & the fuel pressure at 51# & lo and behold, the WOT FP at the top of 3rd was a rock solid 75-76#'s 
& the GN was pulling like a freight train . Seems like the alternator just couldn't provide the current the Walbro 340 needed. Now its time to hit the track again for some T&T. Thanks to all who provided troubleshooting information for me. :biggrin:
& the GN was pulling like a freight train . Seems like the alternator just couldn't provide the current the Walbro 340 needed. Now its time to hit the track again for some T&T. Thanks to all who provided troubleshooting information for me. :biggrin:As for the Delco rebuilt alternator for the TR's...all the ones I bought had the 108A stamped on the case...doesn't mean anything other than that's all they had to use when it was rebuilt...don't think there are a lot of the 120A stamped cases out there to use for rebuilding...if you have any doubts take the alt to AutoZone...Checker...whatever and have them put it on their machine...but if you ordered it specifically for the TR it's the right one...
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