Black Jack: Fixing torque steer

Guess I'm gonna baby it a bit. Might need that mexican block motor sooner than winter.

So, since I'm back in grad school *sigh*... I've handed over some duties I'd prefer to do on my own. The steering rack started leaking so bad I was putting the drain pan under the car in the garage each night and refilling each morning. So, I got the closest mechanic to take some things off of my plate. It was good to get a 2nd set of eyes on the car. He replaced the rack, swapped the oil pressure sender with the early style that actually has a potentiometer (pressure is above halfway on the gauge now, yay!)

, adjusted the hood, which wasn't closing right, and I guess tugged on the e-brake cable a bit and got the driver's rear caliper to stop dragging how it was. Hopefully, that's permanent.

Ironically, I actually prefer the worn out rack's steering, lol. It seems like there was more feedback, before. I can't believe how little resistance there is to turning the wheel, now. But, it does it without noise, and without leaking, now.

I'm on at 1pm tomorrow with Firestone for an alignment, tomorrow. Will do the lifetime deal. I've gotten every bit of my money out of those deals with my truck and with the old Saturn.

Thanks for the suggestions, guys. Lotsa other stuff on my plate, but when I come back to it, I'll try to improve the steering feel.

Minor Update:

Completed wiring the fog light switch to arm the nitrous system.

- Wired the two-step into the Hurst shifter button, along with the reverse lockout and line lock that were already connected there. To avoid being on the spark limiter while spraying, I added a 5-pin relay that’s normally closed for the nitrous circuit but switches to the two-step when the Hurst button is pressed. This ensures both can’t activate simultaneously. The downside is that the nitrous needs to be armed to use the two-step. To address this, I plan to wire in a secondary circuit using a normally closed (NC) relay to power the two-step when the nitrous system is inactive.

- Reinstalled the head unit and shifter trim.

- Installed Fiddle Fart Fab door pins. Ran into Thom Hill at Foxtoberfest and reminded him of our past interaction when I had purchased and returned three sets of door strikers for being too large. He gave me a set to test, and so far, they seem to be working correctly. If everything holds up after a couple of weeks of driving—no rattles or other issues—I plan to order a few more sets for the other cars. These pins eliminate the need for the plastic bushings that always break and fail, which is a nice upgrade.

- I don’t recall if I ever mentioned this, but I also pulled out the hatch striker. Despite not returning the original set after our first interaction, I bought his new hatch striker to try. It’s quite small, so I’m skeptical, but I haven’t tested it yet to confirm its effectiveness.

Tuning, finally!!!

Months ago, I installed the Quarterhorse into an A9L computer I purchased from another SN member. I have been excited to start tuning on it since then, but grad school has been getting in the way. Meanwhile, as the season changed from summer to winter, the car was having more troubles idling and I was stalling it backing out of parking spaces or just turning on the A/C. As a bandaid, I spun the throttle set screw a bit, and pushed idle up to around 1100 RPM. I was already very close to 1V on the TPS, and turning the throttle body definitely pushed it over the threshold, which the computer uses to ID when you are not at idle. It cured my stalling issues, but it caused a CEL & I noticed it was running even more rich-smelling than usual.

I should be doing a mid-term today, but I just really wanted to address this issue. So, I finally cracked into the quarterhorse, set the relevant tables to set idle at 850, turned the set screw back down, and set the TPS.

This has seemingly cured my surging and stalling. The computer was using air and timing to TRY to bring idle back down to the stock 672 setting in the computer. So, it would keep pulling air and timing, and eventually it would almost stall the car, and then flip to trying to save it. Now, with the settings adjusted for 850 RPM, & the window widened before the computer kicks in to try to control the RPM, it just got done running for about 20 minutes in my driveway without any surging. I might play with this later, if I can idle it down another 100 RPM or so with the E-cam, but 850 seems like a nice place to start.

Other Adjustments: I *should* get some added utility from the QuarterHorse...
- Opening up the fuel limiter: My dyno curves suggest a ~6.2-6.3k optimal shift point, but I can't do that on nitrous, because you never want to run up against the fuel limiter. Now, I'll be able to set the nitrous cutoff there, the spark limiter to 6.5k at the fuel limiter above that (effectively turned off)
- 'Calibrated MAFs' have worked just fine for me, and I wouldn't hesitate to use them again, but they are also still just a band-aid. You know, there's all kinds of little settings that don't care about what your MAF is reporting. Injector pulsewidth while cranking, actually setting injector-specific data like voltage offset, breakpoint, & injector high & low slopes should improve driveability all around
- Eventually, I'll turn the dizzy back down to the stock 10* and then adjust the timing from the tables. Until then, I won't mess with the spark tables.

Anyways, it's nice to finally start tweaking the car.

Well, I'll be damned... I've been saying that the factory limiter is at 6,250 for probably 20 years. Turns out, it's apparently different depending on the exact EEC. In the '93 Cobras, Cougar 5.0 says it actually is 6,250. In the A9L, I found the RPM limiter tables, but they didn't add up to any personal experience:


That looks like 7k (assuming it's used despite the fact that the notes tables in binary editor suggests otherwise). But, Cougar5.0 posts suggested that the MNPIP8 scalar actually is the A9L's effective limiter:



So, if I understand correctly, 6,504 is the actual rev limiter with an A9L. I just set this to 6.8k, my MSD to 6.5k, and my nitrous cutoff to 6.2k.

These files could be adjusted and saved, and therefore may not be Ford's original tune, but this is the "A9L.BIN", and it's supposed to be the stock values from Ford. Well, digging a little deeper, I found that the A9P (from a Leech motorsports video comparison) has a limiter at no higher than 6.2k:


Anyways, until you get your hands dirty, I guess you never really know anything for sure.

Edit after test drive:
On a test drive, I can at least confirm that I was able to hold a sustained 6,400 RPM after my adjustments, according to both the MSD signal & the EEC's RPM signal in Binary Editor's live dashboard. Therefore, I can't confirm with absolute certainty that changing the MNPIP8 changed anything, but I can confirm that with it at 6.8k, the MSD Digital 6+ at 6.5k, I can read at least 6.4k.

I went WOT and heard no detonation or anything concerning. After confirming with 1 or 2 brief test runs, I let 'er rip to the limiter and though I could feel torque falling off, my calcs still say it'll be more optimal to shift at 6.5k NA. With the juice set to cut off at 6.2K, I'm going to put a shift light in at 6k, now. I don't know how that will compare to the 5.6k pill I used to have in the light, but I'll report back after the next track outing.

I installed the WB 02 sensor and was seeing WOT AFRs in tge mid-low 12s, a bit too rich, but nothing to worry about.

More tuning updates:
- Shut off the EGR so it's not trying to control anything, and should prevent any codes.
- Reset base timing to 10* (from 14) & bumped WOT spark only by 4* across the board
- Was able to find the "EVP" which is the EGR Voltage. I connected it to my wideband analog output from the Innovate MTX-L. So, now I can see & datalog my AFR within Binary Editor, which is going to be awesome for tuning
- In the Fuel tables, there's a WOT multiplier that the stock A9L uses to add something like 3-9% fuel. I removed that multiplier (set all = to 1), but I also messed with the tables. Here's what the stock Open Loop target AFR table looks like:


So, it looks like it's commanding 12.353:1 AFR from 150* on up. And... that's about what I saw from my WB O2 guage at WOT. I adjusted these targets to the following by multiplying the table values all at once:


So, these AFRs are ballpark where I'd like to see them. I went for a drive and ran it out a couple times. On the first pull, I was seeing 13.3 to 13.5, and on the 2nd pull, I saw as high as 13.7. That's definitely leaner than I'd like it to be. So, I went back and restored the WOT Fuel Multiplier table, for now. It's not my preferred solution, but it should get me by until I can get back to tuning again.


That supposedly multiplies the target AFR in the first tables by the multiplier, effectively enrichening the AFR by RPM.

When I datalog, I should get information that tells me if I need to make global changes (injector slopes), or local changes (MAF xfer function). I may also learn about more tables or settings that might be relevant. I'm basing setting that table to 1 because the Leech Motorsports guy was saying there are more elegant ways of handling Fuel Adjustments. Honestly though, as I review this again, I'm surprised I'm not seeing a Load (x-axis) vs. RPM (y-axis) kind of fuel table. So, this actually is still the way that makes the most sense to me. But, I'm open-minded to his techniques. Just need to learn more.