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Okay. Spark retard and knock counts... I noticed in logs that I'm getting a degree or two of retard around 6000 rpms (33 degrees all in there) but my knock counts on a whole drive cycle are only one or two numbers. I'm speculating that my spark retard isn't necessarily knock just the retard bouncing and doing wonky things because of the rev limiter. That make sense?
So I mapped out a couple data logs... @GregMartin@Buccaneer@Gibbles They are not my best runs by any means but they are pretty consistent between them. I am curious what you all think my anomalies are with AFR between gears 1, 2, and 3... The first and second gear in both are pretty close to where they should be. It is third which seems to go fat (and lazy for that matter.) seems I have some tables to mess with.
Edit: It would seem that my 1/8 marker is exactly where I am going to third lol.
So I mapped out a couple data logs... @GregMartin@Buccaneer@Gibbles They are not my best runs by any means but they are pretty consistent between them. I am curious what you all think my anomalies are with AFR between gears 1, 2, and 3... The first and second gear in both are pretty close to where they should be. It is third which seems to go fat (and lazy for that matter.) seems I have some tables to mess with.
Edit: It would seem that my 1/8 marker is exactly where I am going to third lol.
So to me the data seams quite consistent and what you would expect to see. PE looks like it is commanding an AF of about 12. I can’t remember of the top of my head how that table works. Is it a fixed number or some sort of factor of the VE table. If it’s the latter seeing the MAP trace as well would be helpful. I expect you might see a bit of vacuum in the areas you want to improve, so you could look at that area in the VE tables to change fueling. The rate of change between MPH and RPM is pretty uniform and is related to engine load so it’s doing what it should. Incidentally my car hits a flat sport in first which I have been meaning to look at I expect it’s a similar thing ie pulling a vacuum and entering a different area in the VE table.
Also what’s the timing all in mine likes 36 deg.
So to me the data seams quite consistent and what you would expect to see. PE looks like it is commanding an AF of about 12. I can’t remember of the top of my head how that table works. Is it a fixed number or some sort of factor of the VE table. If it’s the latter seeing the MAP trace as well would be helpful. I expect you might see a bit of vacuum in the areas you want to improve, so you could look at that area in the VE tables to change fueling. The rate of change between MPH and RPM is pretty uniform and is related to engine load so it’s doing what it should. Incidentally my car hits a flat sport in first which I have been meaning to look at I expect it’s a similar thing ie pulling a vacuum and entering a different area in the VE table.
Also what’s the timing all in mine likes 36 deg.
I'm hitting 33 degrees. Map is holding 98-99 with the very bottom 100... so not huge jumps imo.
The AFR table is a table but I have it commanding 12.8 across the board in PE. There is a second table for delta afr that is set for 2. I believe this is the max amount it can deviate in from. I have this dialed back now to 1.5 and will see if that helps.
I'm hitting 33 degrees. Map is holding 98-99 with the very bottom 100... so not huge jumps imo.
The AFR table is a table but I have it commanding 12.8 across the board in PE. There is a second table for delta afr that is set for 2. I believe this is the max amount it can deviate in from. I have this dialed back now to 1.5 and will see if that helps.
For whatever reason 3rd is fattening up.
Yep it’s certainly closer to 12 than 12.8 in third. It has longer to stabilize in third and something is pushing it down. Thinking about it it’s in open loop so I wouldn’t think it would be using AF. It’s a while since I’ve played with the tune on mine so I could be talking out my ****. But I would think that it’s running off the VE table and when triggered to go into PE it just changes the pulse width and tips more fuel in, its not measuring that and doing anything with the feedback loop so I’m not sure.
Yep it’s certainly closer to 12 than 12.8 in third. It has longer to stabilize in third and something is pushing it down. Thinking about it it’s in open loop so I wouldn’t think it would be using AF. It’s a while since I’ve played with the tune on mine so I could be talking out my ****. But I would think that it’s running off the VE table and when triggered to go into PE it just changes the pulse width and tips more fuel in, its not measuring that and doing anything with the feedback loop so I’m not sure.
The open loop commanded AFR is about 13.8 so 2 afrs 2icher would be 11.8... that seems to make sense to me?
Figured its been a while since I updated this. So for now I'll keep it brief. Still haven't fixed the new miss brought on by replacing the fuel lines... there's salt on the road anyway so it ain't going out. (Not to self to call rays rods again because I've been lazy)
My family for Christmas sent out my wheels to be refinished. And while doing that I checked the suspension over and well... all the bushings went from okay in February to basically shot as did the rear hubs... so everything is getting fitted with super pro parts. And SKF hubs out back. Fronts are still fine. I have new BFG tires waiting to be mounted too.
I've decided to redo the rack too. While I'm there. I also changed out the diff fluid and did the U joints on the axle shafts. They weren't bad but the grease was drying out and you could see some browning on the ends... they didn't have much left imo.
I also got a real taurus fan to install and it moves way more air than the spectra unit.
I also Ordered some flex brake lines since the ones out back appear to be seconds away from disintegrating.
Long and short everything went from okay to bad this year. I have a credit card I need to burn now too. And the best part? I'm going to do all this and still need to figure out what the hell happened as to why it breaks up. I have a suspicion that blowing through the fuel pump backwards damaged it. Or one of the injectors suffered a bad fate when my regulator decided to jump from 20 psi to 60 while blowing out the returns. Otherwise I have nothing more. Here are a couple photos.
Been a minute since I've updated this. I will let you know with the under drive pulleys the car has been flawless. It runs a smidgen warmer now that coolant flow is slowed... maybe warmer isn't the proper term. It simply doesn't drop as fast... the time it takes for temps to drop with the fans on is longer but the temps are more stable. Runs upper 190s at speed in 90+ with AC on max so overall I'm fairly happy.
Tune is getting sorted. Runs fantastic. There are a few small drivability things I need to adjust. The car drives better in open loop probably because it's a little fat and that masks deficiencies in the tune like AE and such... it has a slight hesitation in closed loop because light transients go a little lean. So I need to play with AE and PE some more but overall it's 90%. The base calibration for TBI is fairly close.
I am porting away at the stock manifold still. @Buccaneer I will still give Ray a call if he knows anyone that can take a stab at the Renegade fixes but for right now that's shelved.
I'm hoping to get some dyno time in the coming weeks to see what it puts down with the stock intake and then swap to the ported unit and see if it runs better. (It has to right?) As well as a track day. I want to see a solid 1/4 pass out of it.
Now I have a question for you all... when I eventually grenade this block shifting at 6400... what should I build to go in? I picked up a roller block for basically free and it will get a splayed 4 bolt main setup. So would you do a 383, 388 or a 396? I'm thinking rowdy 383. 11.4:1 compression ratio, something around a 236/242 cam. Make it fun. It should be pump gas friendly... 93 is still easy to find here and a cam that big will bleed off most cylinder pressure... I think anything larger is just excessive. That will be down the line hopefully. I'm shoping around for cheap parts at the moment and when I see something come up I am buying it. But I figure the whole long block will cost less than 3k to build no matter the stroke. Then it'll run bottom 11s I hope. 383 seems to be the sweet spot imo but it sounds cool to have a 396 crossfire.
I'd like to follow a 383 build personally. Once I get my '84 project running, that may be the next step I take. And since I know nothing about the build and the requirements, that would be a fun and educational thread for me.
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Originally Posted by 84 4+3
Been a minute since I've updated this. I will let you know with the under drive pulleys the car has been flawless. It runs a smidgen warmer now that coolant flow is slowed... maybe warmer isn't the proper term. It simply doesn't drop as fast... the time it takes for temps to drop with the fans on is longer but the temps are more stable. Runs upper 190s at speed in 90+ with AC on max so overall I'm fairly happy.
Tune is getting sorted. Runs fantastic. There are a few small drivability things I need to adjust. The car drives better in open loop probably because it's a little fat and that masks deficiencies in the tune like AE and such... it has a slight hesitation in closed loop because light transients go a little lean. So I need to play with AE and PE some more but overall it's 90%. The base calibration for TBI is fairly close.
I am porting away at the stock manifold still. @Buccaneer I will still give Ray a call if he knows anyone that can take a stab at the Renegade fixes but for right now that's shelved.
I'm hoping to get some dyno time in the coming weeks to see what it puts down with the stock intake and then swap to the ported unit and see if it runs better. (It has to right?) As well as a track day. I want to see a solid 1/4 pass out of it.
Now I have a question for you all... when I eventually grenade this block shifting at 6400... what should I build to go in? I picked up a roller block for basically free and it will get a splayed 4 bolt main setup. So would you do a 383, 388 or a 396? I'm thinking rowdy 383. 11.4:1 compression ratio, something around a 236/242 cam. Make it fun. It should be pump gas friendly... 93 is still easy to find here and a cam that big will bleed off most cylinder pressure... I think anything larger is just excessive. That will be down the line hopefully. I'm shoping around for cheap parts at the moment and when I see something come up I am buying it. But I figure the whole long block will cost less than 3k to build no matter the stroke. Then it'll run bottom 11s I hope. 383 seems to be the sweet spot imo but it sounds cool to have a 396 crossfire.
Thanks Paul for the update. I've started my new tune from scratch and is running pretty good so far with only a couple hiccups. I "may" have run into the fuel hammering issue at 35-40mph, not entirely sure yet. Odd, it didn't really show up in old tune. The guy I'm working with seems to think it's the inj offset, but not entirely sure right now. We extrapolated the values after 6 volts and made an adjustment, but haven't run it again to see if that helps until maybe tonight for the datalog. I'm on the 7th bin update and it revs pretty fast and VE looks pretty good and added a little more timing at 35* and she likes it, with no knk counts. Had an issue with idle and my IAC count was zero. WTF?! Rear TB worked fine, front not so much. The IAC tested OK and voltage to harness were all good. Replaced the IAC and idles well again. So, EBL was reading zero counts on the rear TB, while the front TB was completely stuck wide open. Rear IAC was trying to compensate for the extra air by going closed, but wasn't working out well. It's just the little things that get in the way. My DC is only 71% at WOT @30psi. Not bad.
I also installed a vacuum pump and my brakes work awesome now and the pump is whisper quiet, I never hear it. Time for a bigger cam. LOL Also, started my TB project on another set of TBs, they should be badass when finished and I will post some pics when done. BTW, my new goal with this motor is 11.99, we shall see how close I can get and that will dictate what mods I need to do/add to get there. GL with your 84 project. I tried calling Ray today and got his VM.
Last edited by Buccaneer; Jun 28, 2021 at 03:22 PM.
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Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.
I have a suspicion that blowing through the fuel pump backwards damaged it. Or one of the injectors suffered a bad fate when my regulator decided to jump from 20 psi to 60 while blowing out the returns. Otherwise I have nothing more. Here are a couple photos.
