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Hey guys!

I have recently finished my first project, a 1965 F100 resto-mod with 2011 crown vic motor/running gear. I have the original Atomic EFI TBI and am having trouble dialing it in. It's been a trial and error process and I just want make it perform better. My current issue is that the truck hiccups from idle to WOT. If you ease into the throttle on acceleration (finding the sweet spot) in runs good. I noticed the Air/Fuel ratio would go severely lean (18-38) during the hiccup, but would correct itself and go back static (14.7). Also not getting that much torque/low end power response, I have a line-lock setup which I can't utilize yet since there seems to be some type of A/F ratio problem. All the hardware works properly, no leaks. No diagnostic problems, the truck runs fine other than previous issue stated. I took it to a local dyno to try and get tuned who altered the settings to which I'm using now. His adjustments did help previous issues but didn't solve everything. I'll attach a video/pictures of my setup below with IAC counts. Looking forward to solving this issue and thanks for any help!

2011 Mod Motor 4.6l 2v (Single Over Head Cam)
Vortech Supercharger S1 trim
Mod 6 6011 box controlling the ignition timing (Current running tune and dyno tune attached) (Part# 121-6011)
Atomic EFI TBI (All the firmware is up-to-date!) (Part# 121-2900)
3-bar MAP sensor

Here is a link for the live gauges (IAC counts etc.) and hiccup problem

*I will also attach additional Manual PDF’s etc.

My current settings: These can be found in the Atomic EFI TBI attached manual for definitions

Cubic Inches: 351 (Motor is 281 cubic inches but it seems to run better on the fuel mapping)
# of cylinders: 8
Camshaft Type: Stock
Fuel Pump Type: PWM with Return Regulator (Regulator is set 50-55 PSI)
Air Pump Equipped: No
IDLE RPM Target: 800
Rev Limit: 6000
Timing Control: Disabled
A/F Targets:
Idle: 14.7
Cruise: 14.7
WOT: 12.3
Nitrous: OFF
Boost: 11.9
Timing Disabled (Mod 6011 Box controls all the timing, this is only for distributor)
Pump Squirt: 5%
Power Valve Enrich: 1% (Was having multiple A/F ratio problems, but the dyno tech brought the Pump Squirt and PVE to here which it's ran the best)

View attachment 51539 View attachment 51540 View attachment 51543 View attachment 51544 View attachment 51545 View attachment 51546 View attachment 51547

Dyno Tune I was given
View attachment 51540

Dyno sheet after Dyno (What I was given, no torque)
View attachment 51547

Current Tune
View attachment 51539 View attachment 51542
Hello Vo0do0,

I see a couple of problems right off the bat with these parts. First the Modular 4.6L 2V engine isn't known for low end torque on a good day. I've had 3 Grand Marquis with this engine and still have one and it's pretty pathetic. Secondly it looks like you have a single plane intake manifold with throttle body injection. This is the second gunshot in the foot as it were. A single plane wet intake (non port injected) is the worst at low RPM for equal fuel distribution. So what is happening here is some cylinders are running really rich and others running really lean. I take it you are running only one or two wide band O2's? If you ran a wide band O2 at every exhaust port you would really see how bad it is. You are only seeing the average mixture with either one or two O2's in the exhaust.

The most probably cause of your air fuel going severely lean during the hiccup is that the already lean cylinders probably misfire during a quick throttle response, this causes a sharp rise in O2 voltage and the computer thinks the engine is too rich and compensates by going even leaner compounding the problem.

I assume you have increased the equivalent pump shot in the software but even then it's just a band aid fix for a more fundamental problem. That intake will not distribute fuel evenly until the engine starts revving and that small displacement supercharged engine will have to rev quite a bit to get that intake to flow evenly.

You would be far better off with multiport sequential injection for this.

2 other problems present themselves. First you really need a MAF sensor on this and I didn't see one in the pictures. The MAP sensor is probably getting turbulent data and the ECU depending on the averaging software is having problems understanding how much load the engine is under, especially being forced air supercharged.

The last problem is no mention of your spark timing map and where it's set at. Are you running a knock sensor for retard? If not I would with a single plane wet intake and forced air induction.

Just thoughts.

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