M45 6psi, J&S with dual display remote monitor (knock based retard and NB A/F ratio display), AFPR, stock ECU, Borla cat-back, 6* BTDC, no other band-aids.

I have surfed and searched, and it looks like its a pointless exercise attempting to adjust my AFPR to lean out the mixture and try to hit 12:1 under boost, because a narrow band sensor/display can't display any mixture outside of 13 to 15 correctly anyway. Is this correct?

Because I spent the last couple days:

1) Adjusting base timing to 6* BTDC to eliminate knock under boost. It appears that I had been running timing at 12* ever since I installed the system in 1999. All these years the J&S had been pulling out up to 12* of timing under full boost to prevent knock, and I had some feedback from Tom@FFS this was leaving unburned fuel, making carbon deposits that were only further seeding the knock events, etc and to roll back the timing.

2) Ran a couple Techron treatments through it. This cleaned up about 80% of the knock when running a 93/100 octane mix (Sunoco 260 GT). Setting the base timing to 6* eliminated the rest of the knock and it even feels like the motor picked up some power, although throttle response suffered.

3) Trying to adjust my AFPR to lean out the mixture under boost, as shown on the J&S display from my stock O2 sensor. I have now turned the adjustment screw out (lean) three full turns from what I have been running since 99, and the A/F display shows... drum roll please... absolutely no difference under boost, except for the knock is now completely gone and it runs very smooth, seems to make better power.

The above has made me think that for my situation

- I should only be trying to monitor A/F ratio with a wideband sensor.
- I should ditch the AFPR band-aid for a PC Pro band-aid.

(Option three: ---- all that and get a MSPNP. I know I know I know I know I understand but I don't feel like ------- around just trying to get the car to cold start, idle, run below 40 degrees etc I don't race it I have a job and family to attend to and if I am going to sit in front of a computer and jack off I'm certainly not going to do it staring at images of fuel and timing maps on a laptop wondering why Autotune didn't respond to the ------- ECU's "do this whatever" signal under load when MAP showed it was well withing limits that user XXX found worked for his stetup just great but maybe not above 5000 feet etc).

I did dig most of the sand out of my vag, I know this question should have been asked oh... maybe late last century, but this is my retro low-hp setup and thanks for your comments.

 

Well, I got one answer today. If a Powercard Pro for a 1.6 is going to cost $500, that makes me want to seriously consider the MSPNP topic

 

I just bought a PC pro (the new adjutable one) and it's nowhere near 500$ lol. Thing is, I bought a MSPNP since and have yet to receive the damn PC. Anyways, I'll be selling mine, if ever you're interested.

 

Yes, PM me when you want to sell it and let me know where it's from, is it for a 1.6 motor? I have a lot of reading to do before I'm ready to jump into MS.

 

In for Joe's epically too literal response to "pretend it's 1996"

 

you already know the answer, because you're not stupid.

get ms and wbo2, tune it (or have someone tune it since you don't sound like you have the time), be DONE

 

sup wit dat turbo?

oh wait you're still in 1996

 

Well fawk. Screwed around with the car all weekend installing FM swaybars, frame rails and a fire extinguisher. Pulled the exhaust while everything was up in the air and found the cat (stock one) was just about completely plugged no sunlight getting through.

Replaced the cat with a hi-flow unit I had lying around waiting for a rainy day, throttle response is back, put AFPR almost all the way back to where it was (it responds to tuning now), bumped up base timing to 8 deg, runs like a champ.

Frame rails and swaybars were a big improvement but that's another thread.

 

You could use some sort of high end Horiba gas analyzer or EGT probes in an effort to get a better AFR reading with 1996 technology.

 

Yeh... go the full retro I suppose. The MSPNP does have me intrigued I just don't know where I'd find the time.

 

Well 1996 arrived uneventfully (thanks 4frnt). I installed the p-p-ppowercard (a TDR supplied Gen III specific to 1.6 supercharged) and ----... it worked the first time out, held its settings and seems to function as intended, no cold soldered joints, bunged connectors or whatever. It feels a lot better than the AFPR. J&S not showing any knock. The factory ECU shows 11.7 A/F at throttle roll-on and it transitions into boost holding this 11.7 to redline like it's nailed there.

Also I put the larger blower outlet manifold on the M45 and this gave an extra psi, peaking to 7.5 psi around 5500 if my boost gauge is to be believed. I'm about 300ft above sea level if that has anything to do with these numbers.

There is a very subtle rasp in the exhaust as if one cylinder is not 100% in line with the rest, so will continue in the persuit of mousepower, do a compression check, replace my 12 year old (25k mile) NGK blues with new ones, gap and install new plugs to replaces the old ones that were probably marauded by the AFPR's various hiccups, see what that does. Then go find a dyno (feels like around 140), maybe there is a slight tune to be had.

Are there any benefits to matched injectors at this power level?