86 Mystery Mods Progress!

So heres my suggestion updated


You must check and set base timing that is imparitive. Id Set the timing to 12* base——>That is with the spout plug removed.
Ohm coil to ensure its within range.
Check that plugs are correct ones and gap plugs to .052
Check that the plug wires firing order is correct.
Check cap n rotor.
inspect plug wires.
I replaced the cap/rotor, they were looking to be due. The plugs are good, and coil tested good. The timing is correct. I also checked the tps, it also checks out. As well the fuel pressure regulator, it holds vacuum and no fuel smell out of it.

After changing the cap it improved a bit, the idle is lower and steady, but it still cuts out under hard acceleration. I videoed the tach as I drove. To show what I'm having going on. Waiting for it to upload


I'm wondering if I'm having a fuel pressure problem, or need larger injectors??
 
I replaced the cap/rotor, they were looking to be due. The plugs are good, and coil tested good. The timing is correct. I also checked the tps, it also checks out. As well the fuel pressure regulator, it holds vacuum and no fuel smell out of it.

After changing the cap it improved a bit, the idle is lower and steady, but it still cuts out under hard acceleration. I videoed the tach as I drove. To show what I'm having going on. Waiting for it to upload


I'm wondering if I'm having a fuel pressure problem, or need larger injectors??

I would get a fuel rail guage. You can buy the kits that are permanent mount pretty cheap. Then you can check the fuel press. It could be running a bit lean i suppose. I think the 93 cobras had 24# injectors with the gt40 heads and intake.

You might be able to get away with an adjustable fuel press regulator if it just needs a little more fuel.

Try unplugging the vac line from the regulator and cap off the line. With no vac to regulator your fuel press will rise about 5psi. Then start and run it. See if things change.
 
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View: https://youtu.be/uWMLoajle2g


Video of the car, it will accelerate fine if I roll in smooth and slow, stumbles when you push it



If its running lean it “should” throw a code.

It could be running out of fuel under hard acceleration. Try the unpluged vac line like i mentioned and drive again. If it improves then id say it needs more fuel. Your injectors are orange so i would assume they are 19# injs and it appears to be a stock fuel regulator. You are well beyond stock with heads intake and headers exh etc. i dont know if its cammed or not. Id say you likely are lean.
 
If its running lean it “should” throw a code.

It could be running out of fuel under hard acceleration. Try the unpluged vac line like i mentioned and drive again. If it improves then id say it needs more fuel. Your injectors are orange so i would assume they are 19# injs and it appears to be a stock fuel regulator. You are well beyond stock with heads intake and headers exh etc. i dont know if its cammed or not. Id say you likely are lean.
Yeah, they are Accel #19 injectors. I'll try it with the regulator bypassed. I was thinking of running my fuel pump at 18v and see if that helps any too
 
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I had a problem similar to that. The pick up was bad and loose inside the distributor. With the cap off you can look down inside the distributor. The part the rotor sits on has square windows cut out of it. There's a pickup that reads those windows. Take a small screw driver and check to see if its loose or disintegrating. Mine actually turned into a dusty white chalky mess. The car still started and idled but I couldn't get on the gas hard.

I believe the pickup is what the computer uses to keep the spark plug fire and timing correct. If I revved moderately it was OK.

Usually, fuel can make it loose power but it doesn't feel like a misfire....or rev limiter. It kind of just won't go when you need it but its not as violent. It'll bog as one event...not multiple cuts at one time.
 
I had a problem similar to that. The pick up was bad and loose inside the distributor. With the cap off you can look down inside the distributor. The part the rotor sits on has square windows cut out of it. There's a pickup that reads those windows. Take a small screw driver and check to see if its loose or disintegrating. Mine actually turned into a dusty white chalky mess. The car still started and idled but I couldn't get on the gas hard.

I believe the pickup is what the computer uses to keep the spark plug fire and timing correct. If I revved moderately it was OK.
I will look at that too
 
Update. Not much, been to cold to work, but I picked up a used stock MAF sensor and housing to replace the "custom" sensor I fixed. I didn't realize but the car has what I'm sure us a explorer MAF housing, which is much larger the the mustangs, but still has the stock 86 throttle body.

What if any issue would having the larger diameter MAF cause? If I read correctly it's still tuned for 19# injectors, but is 65mm instead of 55mm like the fox mad and TB.