Well, the Pontiac is prepped and ready to go as much as she could be for a trip to the dyno this weekend.
Wiring is a mess, no PS and the pump is squeaking something fierce, shoddy fifth gear, no speedo
But the cooling fan works
Have to drive her the rest of the week... flat tire on the Cav and no time to get it fixed till the weekend.
Glad to hear your getting somewhere. Keep us posted with Numbers.
Quiklilcav wrote:Well I'll see if I can get a video up tonight, but here is a picture I dug up on my hard drive. I labeled the prongs where it plugs into the board. If you energize a winding, the needle will point toward the positive charge. If you energize both windings with equal voltage, the needle will point half way between their positive charges. The more I think about it, the more it makes sense that it's simpler to control from a standpoint of the computer, but in order to change the reading, you're going to have to change the signal getting into the microprocessor. It appears from examining the circuit that a 16 pin microprocessor is used to control each motor. I'm trying to trace back the circuit to figure out how the signal comes in to the processor, but the board is multiple layers, so it's not an easy task.
Looks like a nice freaky setup they have.
I'm assuming that:
Since it's running through a microprocessor that it has to be a fairly low voltage.
I'd guess that the voltage is PWM like I mentioned before. And by metering the duty cycle of one or both of the windings you can get the needle to move to an expected position.
Lowering the voltage input to the winding would reduce how fast it moves, but reducing it on both sides I think will probably overall end up taking me in a circle and getting back to the same tach reading.
Here's another thing i'm trying understand. I know the ICM reads the pulses from the crank sensor. It uses that to fire certain plugs. It sends a signal to the ECU, and the ECU sends a signal back on the override line. What does the ICM do with the signal from the CKP before it goes to the ECM? My thought is that it does nothing with it and the ECU reads the same pulses that the ICM sees.
I know that the LN2, the 60 Degree V6, the Quad4 and I'm pretty sure even the ECOTEC all use the same 7x reluctor wheel on the crankshaft. It's 6 evenly spaced notches (60 degrees each) and 1 notch will be 10* away from cylinder 1 which lets everything know to start back at cyl. 1. The same 2 wire VR type sensor goes with that on ALL of those engines. They all use BYPASS, EST circuitry which is similar to GM 7pin HEI.
This is why you can run MegaSquirt with all of these engines, I know that.
I'm just going with an odd chance that it's entirely possible that since both the LN2 and the LA1 have the same setup on the crank sensor that the ECU will still see the correct engine speed. Regardless of how many cylinders it has. If that proves to be true, then the tach would still be correct. The very first step will be to just throw the cluster in there and wire the stock PCM up so it reads a tach signal, and just fire it up. I can verify right away if it's right or wrong, just by looking at the screen on the laptop. If it doesn't work right then i'll be off in the fun of figuring out how the hell to fix that needle reading.
Quiklilcav wrote:SHOoff wrote:...Lowering the voltage input to the winding would reduce how fast it moves, but reducing it on both sides I think will probably overall end up taking me in a circle and getting back to the same tach reading.
Bingo. That's what I was getting at. Since the motor is not linear, simply adjusting the voltage just changes the reaction time, not the position.
They run at very low voltage. If I run 12V to it, the needle moves like the paddles on a pin-ball machine.
You may be right on it using PWM, because that would be the easiest for a microprocessor to control, but I haven't yet determined that.
It would make sense. EV's are PWM. Anything from cars to forklifts and golf carts always run PWM. It's more efficient that way. I can see it being used in a gasoline powered car to reduce the ammount of work that the alternator (which is also PWM controlled if I understand it right) has to do to keep the system charged. Be it a small ammount, but i'm sure it all adds up Plus, it would be easier to do that with a microprocessor than it would for the chip to be controlling some sort of variable resistor.
So those of you tuning your v6 lets hear what kinda spark advance your running.
Im currently running 25 degrees advance on 92 octane with no knock so Im going to bump it up a little more.
-Jason did we ever decide if 57 was the right offset or am I really running more then 25*?
Quote:
I'm going to hook up my multimeter and see what it says. I'm not sure it will give me an accurate reading on a pulse, but we'll see what happens.
You have one of those cool DMM's with an oscilliscope on it? Nice! Those are a tad on the pricey side, but i'm sure I want one.
Quote:
So those of you tuning your v6 lets hear what kinda spark advance your running.
Im currently running 25 degrees advance on 92 octane with no knock so Im going to bump it up a little more.
-Jason did we ever decide if 57 was the right offset or am I really running more then 25*?
Sounds like you're still running my timing table.
I've never gotten to seeing if that's correct. If it's actually 53 and you're running 29* I could see it starting to knock with stock cam, but... it might not, so I don't know. I do have a timing light available, but the thing is, with electronically controlled timing there's not any timing marks to use. So i'd have to make some, and a pointer.
All in all though, you can still tweak the timing and get some HP from it. Just if you end up at 30*, that might not be the same as 30* on a setup with a factory PCM.
I am but its tweaked slightly at WOT. Check yours at WOT it is I think 20* or 22* cant remember for sure.
How many of you guys are installing or have installed your 3400's without touching them parts/performance wise? Say without replacing the lower intake manifold gasket or anything else? I'm going to install mine just the way it came out of the donor car, but as soon as I get some mileage on it to be sure I have everything done right, I'm getting another motor, and have it professionaly built.
I know black cat custom clusters are pricey, but can they be made with a 260Km/h speedo, and can the be made to work with say grand Am ECM?
Michael Antle wrote:How many of you guys are installing or have installed your 3400's without touching them parts/performance wise? Say without replacing the lower intake manifold gasket or anything else? I'm going to install mine just the way it came out of the donor car, but as soon as I get some mileage on it to be sure I have everything done right, I'm getting another motor, and have it professionaly built.
If nothing else was dont to the engine, I would recommend at least changing the lower intake gasket, especially if its showing signs of leaking.
Mine had 50k miles on it and it was leaking but not showing external signs yet.
Your choice though.
01 cav w/01 3400 gam gt 4t45e
I know this is off topic, but I need help really fast. Can one of you guys tell me how to remove the base of the mirrors from the outer mirrors? I can get them apart by removing the springs with pliers, but it just seems that they'll be impossible to put back together the same way...
michael, to put them back together use a piece of strong wire, make a loop at the end and attach one end of the spring . stick the other end of the wire through the mirror where it attaches. attach the opposite end to the mirror where it goes. Put the mirror together and pull on the wire so you can hook the spring, then cut the wire off.
01 cav w/01 3400 gam gt 4t45e
joe malechowski wrote:Michael Antle wrote:How many of you guys are installing or have installed your 3400's without touching them parts/performance wise? Say without replacing the lower intake manifold gasket or anything else? I'm going to install mine just the way it came out of the donor car, but as soon as I get some mileage on it to be sure I have everything done right, I'm getting another motor, and have it professionaly built.
If nothing else was dont to the engine, I would recommend at least changing the lower intake gasket, especially if its showing signs of leaking.
Mine had 50k miles on it and it was leaking but not showing external signs yet.
Your choice though.
Since the engines have a problem with them, I'd reccomend changing the LIM gasket regardless. Even if they've been changed it seems like they still have a tendancy to blow out.
Quiklilcav - I found this on that 2.2 rebuild thread in this forum.
Notice that the notches on that crank ring appear to be 60 degrees apart. The 2.2 ECM should read all the notches, but will only make use of every third one so that it makes a firing event every 180 degrees. The same ring should be on the V6, but the ECM will make a firing event on every 2nd notch which would be 120 degrees. I'm waiting on an ebay auction to end so that I can get a cluster with a tach to find out how the ECM actually reacts.
If thats the case then why would my tach work? It seems to be dead on too. Maybe the ecm reads all of the notches and sends that signal to the cluster through serial data, but only uses the second or 3rd for firing purposes?
01 cav w/01 3400 gam gt 4t45e
Quicklilcav - That's what I'm wondering too. I know if I hook both computers to the CTS (2 wire) it will move the gauge to the proper spot since the factory PCM is reading correctly, but the voltage is low at the MS-II (which is in the trunk of the car) so it only reads around 90 degrees when the engine is warmed up. But that's based on a varying voltage in relation to temprature. I am hoping that it won't be the case since the tach signal should be in pulses. I'll be able to tell immedietly by looking at the laptop screen wether or not it's getting an accurate engine speed reading.
joe - I thought you were using the GAGT computer. In that case by all means it should be reading the v6 engine correctly. The reason your tach is working is because the PCM sends engine speed through the serial data connection as part of the stream. What i'm trying to do is use a 2.2 PCM to read it. This should be no problem if the ICM does not modify the signal as both engines have 7 notches on the crankshaft. It is a possibility that the ICM reads all the notches, but only sends a signal when an event is supposed to happen where it would send 3 events per engine rotation for a six cylinder and 2 per rotation on a four. I am worried about this since aftermarket tach's don't work properly without an adapter on the J-bodies.
If it doesn't work, there could be a way to get the Megasquirt to send a tach signal and I could utilize that for the factory PCM.
My buddy bought an aftermarket tach for his civic and couldn't get to work. I popped the hood on my car and got it working in a couple minutes, without using an adapter.
