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Discussion Starter #1
Hey all, thanks for the help in advance.

I installed the Accel points eliminator and a blaster solid coil with a full 12v going to it (bypassing resistor wire). I recently rebuilt my stock distributor and installed a new vacuum advance. The motor is a 289, mild cam, intake and headers and the car has been completely rewired front to back.

Car starts perfect and idles perfect. If I rev slowly it climbs the rpm's just fine. When I grab a bunch of throttle it begins to pop like popcorn out of the Holley carburetor. I've adjusted the timing from 5' all the way up to 20' with the vacuum line plugged, and no change. Other than a possible sticky intake valve, any ideas that I may be missing? Thanks.
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Discussion Starter #3
Hmmm I'll pull a plug tomorrow and check. I've been poking around the search function and heard everything from a wiped lobe to sticky intake valve. It doesn't backfire like that though.... strange. Just small "pops".
 

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A wiped ex cam lobe or a sticky valve were my second guesses. If you have vacuum secondaries, install a stiffer spring over the diaphragm and see if that helps. If you don't have a set of springs, you should have them anyway.
 

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Did you reset your timing? Anytime you touch anything in the distributor, timing needs to be reset. Popping through the carb is late ignition timing
 

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Discussion Starter #6 (Edited)
Did you reset your timing? Anytime you touch anything in the distributor, timing needs to be reset. Popping through the carb is late ignition timing
Reset my timing, what do you mean? Check to ensure the timing is set properly? I'm sitting at ten right now, 750rpm. Moving up or down has no effect on the popping I'm hearing.
 

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The Accel trigger or Blaster coil is misfiring? Put your points back in and see what happens. Put your original coil back in and see what happens. It won't hurt anything to run it on the full 12V for a couple of minutes.
 

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Discussion Starter #9
I'll swap everything out as suggested. Just out of curiosity, this condition may coincide with when I bypassed the resistor wire and went full 12v to the coil. It's the 1.5 Ohm Blaster coil if that matters.....
 

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Hey all, thanks for the help in advance.

I installed the Accel points eliminator and a blaster solid coil with a full 12v going to it (bypassing resistor wire). I recently rebuilt my stock distributor and installed a new vacuum advance. The motor is a 289, mild cam, intake and headers and the car has been completely rewired front to back.

Car starts perfect and idles perfect. If I rev slowly it climbs the rpm's just fine. When I grab a bunch of throttle it begins to pop like popcorn out of the Holley carburetor. I've adjusted the timing from 5' all the way up to 20' with the vacuum line plugged, and no change. Other than a possible sticky intake valve, any ideas that I may be missing? Thanks.
View attachment 737147
What's a Blaster solid coil?
MSD blaster? Blaster 2 or Blaster 3? Those are .7 ohm coils. The ohm requirement for your points eliminator kit is 1.3 ohm.
Check out your installation instructions.....
 

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Two switched spark wires? Most of the time if you swap two you'll get a big obvious misfire. But if you swap two that are adjacent in firing AND in the firing order it might idle just fine and then misfire when required to produce actual power. #7 and #8 would be prime suspects.
 

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Discussion Starter #12
Sorry gents, blaster was the old coil. I now have the pertronix flamethrower in there at 1.5 ohms recommended for SBF. Just took her out for a spin, same issues. Worse under load and hard accelerating. Just sounds like popping thru the carb, but cruises perfectly. I need to dig out my points and I'll throw those in as suggested above.

Wires have been checked again, all good.

I'll check my accelerator pump on the holley and open the valve covers next.
 

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Discussion Starter #14
Flamethrower 1.5 ohm coil is a "points replacement" unit and requires external resistance.
I found an old ballast resistor in my parts bin and wired that in, no change (is that what you meant woodchuck?). I then swapped in my old MSD Blaster coil in, no change either. Starts up great, pops when you give it gas.

Accelerator pump appear to be working properly, hug jets of gas instantly when pumped.
 

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I found an old ballast resistor in my parts bin and wired that in, no change (is that what you meant woodchuck?). I then swapped in my old MSD Blaster coil in, no change either. Starts up great, pops when you give it gas.

Accelerator pump appear to be working properly, hug jets of gas instantly when pumped.
Yeah. Okay... how's your separation of plug wires to cylinders #7 and #8? (Assuming you're not running the 5.0HO/351W firing order....)
 

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Discussion Starter #16
UPDATE
Must have been merely coincidental with the accel install.

I pulled my valve covers and started the car, number 8 cylinder intake valve is barely moving like the rest. I moved that cylinder to TDC and the valve is up. I pulled the pushrod out and it's not damaged. I reinstalled, adjusted those valves and same result.

Either a wiped cam lobe or bad lifter. FML.
 

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I installed the Accel points eliminator and a blaster solid coil with a full 12v going to it (bypassing resistor wire).
I use that type of ignition and it has always worked perfectly. The ignition module does require a ballast. The Installation Instructions begin with this statement: "IMPORTANT: Before installing the ACCEL Points Eliminator Ignition System, make sure that your vehicle is equipped with an ignition ballast resistor (or loom resistance wire) in the wire between the ignition switch and the coil (+) terminal."
 
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