I actually had them involved for a while.  I told them what was happeneing and they though it was because the original system I purchased was for a bored over but not stroked 302.  They burned a new chip to supply more fuel because of the stoker kit I put in.  I installed the chip and it still does the same thing.  I asked if I needed bigger injectors, the kit supplied 32 lb, but they said no.  The injectors I have are supposed to supply upwards of 500 hp and I dont think I am that high.  Could it be the mallory box or distributor?  Maybe both?

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i would plug the distributor vacuum advance and leave it plugged until the problrem is fixed.

after engine is warm do the following:

loosen bolt an distributor 1/4 turn.

start engine and rev it to almost 1/2 throttle or 2700 rpm and hold it.

advance timing 3 degrees.

if the rpm increases and it still runs smooth, lower the rpm to 2700.

advance the distributor 3 more degrees,

if the rpm increases and it still runs smooth, lower the rpm to 2700.

advance the distributor 3 more degrees.

if the rpm increases and it still runs smooth then atop the test.

note the timing at the setting that has the most rpm but still rubs perfectly smoothly and tell us what it is.

also, spark plug wires can do exactly what you are describing even if they are new.

also, high energy ignitions can cause the spark to jump from one post on the distributir to another so you might need an hei cap but you can check the phasing of your rotor first . . if it is out of phase it can cause the problem.

put number 1 cylinder on 10 degrees btdc compression stroke.

mark the distributor body where number 1 spark plug wire post is.

remove distributor cap and look at the line on the pickup . . it must be lined up with the point on the reluctor . . if it is not, rotate distributor until it is.

look at the rotor, it must be lined up with the mark on the distributor . . if it is not, loosen the screws on the rotor and position it so it is.

set initial timing to your spec.

check spark plugs for carbon . . if you have a high voltage coil, set the gap to around .042"

you should bypass the standard igbnition wire and run a wire from the back of the switch to the pos side of the coil.

if you have an electric choke and it is connected to the ignition wire or the starter solenoid, disconnect it ans connect it to the back of the alternator . . set it so it is fully open after 4 minutes or less with the key on.

how much fuel pressure do you have?

Last edited by barnett468 (4/09/2015 3:23 PM)

What fuel pressure do you have at idle?

Also burned a chip? I thought that was a stand alone EFI that you tuned with a laptop?

One more thing, what is your firing order? Did it change with the cam swap?

 

Last edited by Raymond_B (4/08/2015 2:19 PM)

Now if it was ECCIV I'd point to check vaccum leak.

Tubo

What fuel pressure do you have at idle?
40 psi at idle
Also burned a chip? I thought that was a stand alone EFI that you tuned with a laptop?
The new ssytem they went to all you need is a laptop and I might need to upgrade the computer, although I dont have an extra 1,000 laying around right now.
One more thing, what is your firing order? Did it change with the cam swap?
The cam was ground with a 351W firing order.  

The old computer that I purchased from Mass Flo, now Pro M, has a removable chip that can be re-flashed.  I had Pro-M reflash my chip to my current specs.  It didnt make a difference when I installed the new chip though.  

This may be a software problem, or a hardware issue.  Bad injectors, bad O2 sensors, bad data stream.  But in any case, this is an issue for Pro M to get stuck into.
What you need to do is take a data snapshot.  Then send a copy to ProM for them to diagnose.
ProM should be able to tell you exactly what connector (OBDI or OBDII), and what datalogging program to use.  They will get you to use the program they are most familiar with. 
The beaty of EFI systems is the ability to log and examine the engine settings and performance.  Obviously there is something very badly off with your engine, and most likely in the tune.
This is the avenue you should pursue firstly and firmly.
There are a lot of free programs that will allow 20 or so data grabs without charge.  Do you have a dataport on your system now? (USB or some version of a data cable port)
You can download a efi data program to your laptop, then plug into your data port and drive your car for 10 minutes or so, which will collect a huge amount of data.
At this point ProM should analyse the results and figure out what is wrong.  EFI systems should run smoothly and give excellent power.

One completely different thing to try is take off the EFI and try a good  running carburetor and intake.  As a test it is uncompromising.  If it runs well, ....it is the EFI unit. A lot of work maybe, but there will be no arguing with the result.  I only suggest this in case there is some reason you have not had this out with Pro M before this. 

Also it's kind of hard to read your replies the way you are doing them inline with no designator. Just sayin

Anyway, have you verified that the firing order in the software matches that of the cam?

Is the EFI batch fire or sequential?

Are the injectors wired for the correct firing order?

How do you set your base timing? Do you have a spout to pull? Does the software assume a certain base?

Are all the sensors reading correctly?

What type of O2 are you using?

What type of logging can you do?

I could think of many more questions, things like chassis ground, sensor ground, VREF, and on and on. I don't know that system, but most share a common framework.

DC wrote:

I have worked up two EFI conversions, both based on stock mass flow parts and wireing. That gives me the capability to use my existing analyzer to watch what is happening real time by setting up the sensors I want to look at on the analyzer screen.I just hook up to the OBD2 connector. Does your laptop connection and software let you do that It can really help in troubleshooting.

DC, which wiring harness are you using that is OBDII? I've done several Mass Air conversions using 89-93 harnesses, but they aren't OBDII.

jims72 wrote:

Well, I don't know if this applies, but I once ran a Mallory non vac. advance dist. Spark plugs would last about 50-100 miles before cutting out above 3g's. Idled OK, crused OK, but get on it and it'd miss like crazy. New plugs, it'd run fine for a day or two....j

Welcome Jims72.  That's a decent suggestion. 

BB
 

Raymond_B wrote:

Also it's kind of hard to read your replies the way you are doing them inline with no designator. Just sayin

Anyway, have you verified that the firing order in the software matches that of the cam?
I contacted Mass flo to ensure the firing order was correct.
Is the EFI batch fire or sequential?
it is sequential fire.
Are the injectors wired for the correct firing order?
Yes
How do you set your base timing? Do you have a spout to pull? Does the software assume a certain base?
I set the base timing by verifying cylinder one is on TDC and then adjust while the engine is running with the SPOUT disconnected.
Are all the sensors reading correctly?
I do not have any trouble codes that show on the light or when I run trouble codes.
What type of O2 are you using?
Not sure but I have included a pic.
What type of logging can you do?
The connector that I have to read codes just a 4 pin connector.  I will incleude a pic on another post.
I could think of many more questions, things like chassis ground, sensor ground, VREF, and on and on. I don't know that system, but most share a common framework.

Does anyone know if the connector I posted is something I can even hook a laptop up to?  What does the type of O2 sensor do to effect the system?  I am going to try to check cam phasing with the distributor.  Any other ideas?