VERY IMPORTANT INFO! could explain alot of engine failures!!

[HISSMAN]

200-225A?? That is crazy output.

 

[illadvisedSnake]

.....changed it out and now they are in the high 12's at higher rpm's!!

As I originally suspected, changing to a higher amp alternator has masked the problem. Why do I say this? Simple. High 12's is still too low unless, of course, the car is 20 years old.... Mine stays in the low 14's at WOT, very close to what it is at idle.

Willie

Not to beat a dead horse with this but I think I agree with Willie. Has anybody checked the voltage directly at the MAF? Many of the sensitive measurement devices use 5 volts for this reason. 12 volts hooked to a 5 volt regulator so there is very little voltage drift to ensure a 5 volt line input. If the voltage was to drop below 12V (I see somebody was reading 11.5V through a raptor) I'm not sure if that would effect voltage on the 5V side? there should be a threshold of like 10-14v for operation...
just a thought...

EDIT: actually I take this back (original message in black font)..... I just found out that the MAF on the terminator IN FACT DOES run off of 12V!

this is from a relay of emails from terminator designers...
"the MAFS does not use a 5V reference. It is indeed a 12 volt supply into the MAFS.....

.......underdrive pulleys? Those could be the first culprit if there really is a low voltage situation. I assume he measured the supply voltage at the MAFS. What exactly is the concern anyway? It seems to me that a low voltage situation there would be a blessing in disguise for power as that would drive a lower than actual AM reading, thus tossing in a little spark and less fuel which as long as they are not running catalysts would be a recipe for a fast terminator."

I would assume he's talking about a lean condition on a stock terminator... this making Herman's finds true if the voltage at the MAF was droping below 12V. (BAM there is your lean condition) Not good on a modified terminator already close to a border A/F/ Not sure if anybody actually checked voltage at the MAF but it the battery itself was below 12V how could the MAF have 12V....

 

[Evilcartman]

Watching....

 

[kennycoulter]

i want to start off with saying that i have no clue about electrical systems.
i absolutley can not read all of this, but would any of it change with a larger/ more ground cable? i know for the 944 croud, we have lighting problems that we correct with a 4 or 0 gauge welding wire from the alternator, and add another to the block to the frame.
does a capaciter store electricity?
im concerned, because im about to put on the alt pulley and 4 lb lower from metco.
anyone find a true correction to the problem yet?
when dyno tuning, do you measure voltage at the battery, alternator, or the maf?
also, doesnt the engine have a knock sensor? doesnt it retard timing if it detects knock? is the system faulty because of additional drop in power to the knock sensor?

 

[sbc.cobra]

well i read the whole thing...can i get some cliff notes now

w/ my whipple at 19lbs...(stock upper/6lb lower) i have a 3.5" alt pulley. stock alternator. should i upgrade my alternator? i am confused by all of this stuff. what should the voltage read in the higher rpms?

 

[apg2369]

2.93 upper 4# lower stock alt pulley, optima red top

12.8 car off, at battery

13.7 car on at battery

13.9 wot , with scanner

at 6,400 rpm a/f 11.4 from wide ban o2 scanner

no problems....knock on wood !!

 

[donpablo]

Zoinks! Subscribing!
Thanks Much Herman.

DP

 

[oldnfast]

Herman, I want you, and a select few in this thread for my defense team at my murder trial.

 

[Evilcartman]

Ok, I'm about to install a 6lb lower and a 3.1 or a 3.4 upper. Should I install the bigger alt pulley? Is it better to over spin the alt and make sure I have enough juice on the top end, or put a larger alt pulley on? With a 6lb lower, should I go with the 3.5 alt?

 

[FLYIN]

.

 

[BlackGT03]

Now, I see the consensus of this thread is to get a better alternator, but the capacitor idea kind of went out the window, would the capacitor aid in the time you are in WOT to keep the voltage up? If so, how long would it help keep the voltage up?

 

[roach4047]

subscribing...lol...so can anybody update?

 

[SickBlackMach]

Anybody consider doing this? Seems like it'd be a good thing to do.

http://forum.sounddomain.com/forum/ultimatebb.cgi?ubb=get_topic;f=5;t=007801;p=

Just found this thread, and was going to post up this info!
I have been thinking of going with the PA 170a alt, as a precaution. I already have an red top, fwiw... I would log my VDC vs RPM, but I cant find the damned predator! lol

 

[03 DSG Snake]

Wasn't it found that the PA Alternators were crap?

 

[iczar1]

Can someone put a write up on how to test our Voltage?

Where can we get a Volt Meter?
Where to place the Volt Meter for monitoring?
What other hand-held Devices can also mointor(aka Predator/Dash Board)
---Any subtracting/adding that needs to be done
---The PIDS that we need to select

Thanks from those of us who arent that technical

 

[03 DSG Snake]

Just found this thread, and was going to post up this info!
I have been thinking of going with the PA 170a alt, as a precaution. I already have an red top, fwiw... I would log my VDC vs RPM, but I cant find the damned predator! lol

Anyone else do those 'grounding mods'?

 

[iczar1]

So the problem was solved by adding a high amp alt?

Anyone have a how-to on testing the amp output of your altenator?

 

[TRiedy]

subscribing

 

[04MC]

There was never an update here .... :sleeping:

 

[SDBOLT]

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