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Getting Started: LO3 Camaro

Put about 120 miles on it last night. Starts great, runs good, BLMs are in line when driving.

Still rich at idle. 110ish on BLMs. And it hunts at idle in gear and park. There's an idle/spark correction PID I've heard about disabling to help with that. Might start emulating and try and tune it better or I might drop the PID completely for now.

I want gears and a TrueTrac but I also want headers and a better exhaust and cam swap and ya know, EVERYTHING....
 
Spent yesterday and today getting cooked on the paper machine and it's too humid to think outside. Car will have to wait till I can be outside for 5 minutes and not sweat through my shirt....
 
Tonight was not as miserable so tonight after dinner I played with the car a little.

First thing I did was turn the fuel pressure up to 13psi. My O2 voltage was in the 800 range at WOT and I was getting a good bit of spark retard so I was pretty sure it was leaner than I wanted.

Next I decided to try emulation. I cut the idle overspeed and underspeed spark tables in half and zeroed the idle multiplier tables and that stabilized the idle RPM issue I was having. Then I played with the idle speed a little and leaned out the 600x25 to 800x40 section of the idle VE table 5%. That brought my idle BLM right to 128 and seemed to improve idle quality some too.

It seemed to go ok till I started getting blips, CEL would flicker and the idle would jump to 1000. It eventually died and wouldn't restart. I fiddled with it and decided to swap back to my chip. It still wouldn't start. I unhooked the battery for a few minutes and it still wouldn't start.

I suddenly fired up and idled. I swapped back out to the Autoprom, it started, idled. Cool. I pulled it in gear to go play a little and the second I hit the gas pedal, it died and wouldn't even try to restart.

I swapped back to the chip, cycled the ignition 3-4 times and it fired up. Not wanting to get stuck on the road, I burned my changes to the chip and just drove on the chip instead of doing any more emulation this evening.

The car runs tremendously better with the 13psi. 5500RPM easy between 1-2. Much more responsive 3-2 downshift acceleration. I have a long log to review and see what I want to change next.
 
I finished mowing, weed whacking and blowing the walkways clean at 11:45. Almost brain farted when I walked into the cool house to eat lunch. Got real dizzy.
 
Took it out this morning doing some emulation and it ran OK for about 40 minutes. It started struggling so I popped the chip back in and headed home. I parked the car and went in and made some changes I wanted to burn to the chip and kept getting a validation error. I chatted with Craig at Moates and it looks like my Autoprom burned up a component so it'll be headed back to him for repair.

I was able to emulate and get the car back in the shop. This is my kinda luck.
 
I did add some timing and the LO3 does not want more timing than the stock tables. I immediately started getting knock with any amount of load while driving.

Once I get my AP back, I may throw a little timing at the PE/WOT table and see if it will tolerate that.

While it's not running, I probably need to throw a transmission filter and some fresh fluid in it.

I have learned a valuable lesson about keeping my current "known good" tune on a backup chip so if I have trouble, I can at least drive the car.
 
I've been trying to take it easy and enjoy the weekend off but I took a few minutes today to throw the drivers side under dash panel back in.
 
Waiting on my prom burner to get back to me, I pulled the #1 plug just to have a look. Any amount of additional timing creates knock in this thing but I went down a spark plug rabbit hole and got to wondering if I could run a colder plug, 43 instead of the 45s in there now, and possibly be able to up my timing a little.

Plug looks good. These are the best pictures I could get of it. These don't have but a couple thousand miles on them since I started working on the car again.

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20260709_181200.jpg

There's minimal transfer so I don't think the 45s are necessarily too hot for it now. It's also a pain to pull the plugs out of this thing so I wasn't in the mood to put it on stands. (too much pizza this evening)
 
Out of curiosity, I looked up the plugs for a 1989 C1500 with the flat tappet LO3. It calls for R43TS where the Camaro calls for R45TS. Maybe that tends to let the trucks take a little more timing since it seems like a lot of folks can dial in 3-5 degrees pretty easily? Or maybe most folks are actually looking at knock retard numbers in their logs?
 
Been working through the tune some. With help of one of the TBI old heads we built a more-stock VE and spark table.

Also, the Edelbrock Intake feeds the banks from opposite sides of the intake so I swapped injector plugs and it slightly changed my BLMs but not a huge improvement.

There's a bunch of knock in the upper RPM range at WOT and it may be due to my ICM. The original TBI ICM apparently pulled some of timing above 3600RPM. The ICM in my replacement distributor is from a RAM Jet and/or Marine engine and I can't find any info on its behavior. I've zeroed my PE timing adder table till I can get a handle on that.

One other issue I'm dealing with is my TCC unlocks around 80mph cruising. My TPS is between the lock limits so I'm guessing it has to do with the TPS rate of change but I haven't had time to start messing with it yet.

Blondie and I took it for a nice ride over to Lexington yesterday evening for a chili dog and a milkshake. I let her drive, she absolutely loves the car and we're working on how to safely drive aggressively. Maybe I'll get one hot rodder out of the spawnlings.

The car ran great. I think I need to work on my idle VE table some. The BLM jumps around quite a bit between low load and idle and I need to get a better handle on that.
 
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