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LSX454 swapped 95 BASS burb.

Little lower, little cooler, bigger sounds.
That points toward acceleration enrichment being off. We should tweak that and see what it wants.



If we can't tune it out, that would mean the converter is still too tight for that combination. We need to do some tuning. Do you want to send me the tune you are currently using your best data log and I can tweak the timing and you can try that. And then after that we can try tweaking the fueling if you want. It would be much easier if I was in person but we should be able to tell if it's the tune or not.



I would use Dex VI, I believe all Dex VI is full synthetic.



I still don't like the way your MAP drops at WOT. Are you sure your air filter is not plugged or something? Maybe on a clear morning with dew on the pavement you should make one test with no air cleaner or something.
The launch was the best yet, and I had turned down the Acceleration enrichment. May try down a tad more..


I'll do one more good datalog with a less screwed up beginning, and then send you both.

Dex6 may be what I'm thinking of. It was full synthetic is all I remember.

I plan to buy another filter just like mine. So that I can clean one and let it dry, while running the other.
Right now my filter IS dirty, but looking through it with a light it seemed more than open enough.:dunno:

I did see that the Edelbrock of the same size claims it's only good to 470hp...? Makes me wonder if I should ditch the air box and go bigger.

It'd be getting hotter air then though.
 
I noticed something that I've been going to bring up, but kept forgetting with all the other stuff going on.

When I'm cruising easy in third gear at 60-64 mph (3000-3200 rpm) I get a repeating harmonic type vibration.
Slow like 2 sec on, 1 sec off.
It doesn't do it anymore if I shift to 4th, even at 3100 rpm in that gear. Or at that rpm in any other gear.

I was kind of wondering if that's it's sweet spot where it has the least load.
I'd think of it was Drive shaft, read end, wheel bearing, etc. it'd happen regardless of the gear it's in.

Should I upgrade the harmonic balancer maybe..?
 
Maybe.. its all rubber mounted now and wasn't before.
But,
I can feel it in the truck. Like in the floor under my feet, and the door under my elbow, etc.:dunno:
Super low and almost un noticed. If it had a radio I'm not sure if have picked up on it.

Probably nothing....

Think my sub conscious mind is just trying to make excuses for me to buy an ATI super damper lol.
 
Something I thought of when I looked into adjusting timing in my dead spot.
The Holley has a set timing for WOT. And when you put it to the floor, it goes to within a degree of that and stays there.
So even if I change the values in that area, it's not going to help on a WOT run ...... ? Right?

This last run at least looks better.

But you can see what the timing does from the moment I push the pedal.

IMG_20240929_074149214.jpg
 
Also... With that flat spot at the start.... If that's the flash stall point, it happens after I'm already climbing speed. Because my speed has a dip at the same place due to the rpm drop.

My 0-60 on that run is back to 5.8 even with that flat spot. That was my previous second best time.
So if I could at least lessen that flat spot, it'd be faster.

Couldn't get it to burnout today. It'd spin em, but it was like before. Even slowly getting into it they'd break free and real slowly roll over. Couldn't get them to go faster, and mostly just pushed the front wheels down the street leaving black marks that way lol.
3 tries, same results.
 
Once I add 600-700# of stereo directly over the rear wheels, burnouts are going to be a pipe dream.
Unless I do a boosted BB or something .
So I guess I stick to playing around with the power, and do burnout's with the 350 rocket in the Cutlass if I keep it.:dunno:
 
This is a rolling start smash from 45mph and 2300rpm.
WOT timing changed up to 32. And the area in white blended in so it increased also.

May have made it worse:dunno:
Rolling pedal mash made for a full 2/3 of a second dead spot.
2/3 of a second doesn't sound like much but feels like an eternity when you push the pedal and expect the truck to go faster lol.

IMG_20240929_223312043~2.jpg

IMG_20240929_224210536.jpg
 
How do I get to this.... Live tuning, with the little orange dot that moves in time with the MAP and RPM

I've looked everywhere, and can't find it.

I don't know that it's necessary.... But it'd be cool to see:dunno:lol.

Screenshot_20240930-023915~2.png
 
How do I get to this.... Live tuning, with the little orange dot that moves in time with the MAP and RPM

I've looked everywhere, and can't find it.

I don't know that it's necessary.... But it'd be cool to see:dunno:lol.
You have to have the computer online with the ECU while the engine is running, then you can do live tuning. You can literally change a cell and you can immediately hear if the engine likes it or not. Its one of the fastest ways to tune if you sit in the passenger seat while someone else drives and just tweak it. Make sure you download the tune from the ECU and then if you go "online" with the USB link while you run the engine you will see live tuning.

One time I had to tune my brothers supercharged 468 without an O2 sensor, because it was junk when we put the used EFI in it. This was original FAST EFI, no self tuning either, so he just drove around while I tuned it by sound, smell, and feel. Meanwhile my dad would follow us and say whether there was black smoke or not. Basically I made the base tune real rich to be safe and then backed it out until it was running real nice without black smoke.

It sounds to me like you are learning tuning yourself. You try something, see if it likes it, listen, smell, feel, and then if it likes it try a little more, if it doesn't try the opposite. Experience will get you tuning faster because you know which way to go and how much quicker, but its still basically the same thing.

The self tuning makes it really easy, because you can just change the target A/F ratio and let it try it if you want. But there is a large window where the engine will run fine, much bigger than you think.

Timing is much more critical, if the timing is off it can lose a lot of power or destroy the engine pretty quickly, although with a pump gas NA motor you should hear it (pinging) way before you hurt anything.

The acceleration enrichment is not self tuning, only the learn table, which is combined with the main table, is self tuning. Also, timing is not self tuning either, neither is cold start fuel, etc. It can only tune the learn table when the engine is warm and everything is stable and you are not changing throttle positions.
 
Couldn't get them to go faster, and mostly just pushed the front wheels down the street leaving black marks that way lol.
3 tries, same results.
If you have more traction in the back then you do in the front that will happen every time, it will just push the front.

Maybe you need skinny tires in the back only, ha ha.
 
I noticed something that I've been going to bring up, but kept forgetting with all the other stuff going on.

When I'm cruising easy in third gear at 60-64 mph (3000-3200 rpm) I get a repeating harmonic type vibration.
Slow like 2 sec on, 1 sec off.
It doesn't do it anymore if I shift to 4th, even at 3100 rpm in that gear. Or at that rpm in any other gear.

I was kind of wondering if that's it's sweet spot where it has the least load.
I'd think of it was Drive shaft, read end, wheel bearing, etc. it'd happen regardless of the gear it's in.

Should I upgrade the harmonic balancer maybe..?
Try going the same speed in a different gear, but you may need the same load, to me that sounds like driveshaft or tire balance, but its hard to say without being there. You need to determine if its only a certain speed, it sounds like it's not related to engine RPM. Is it related to speed or load?

If its in your floor and seat try putting the back tires in the front and see if it gets in the steering wheel.
 
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Something I thought of when I looked into adjusting timing in my dead spot.
The Holley has a set timing for WOT. And when you put it to the floor, it goes to within a degree of that and stays there.
So even if I change the values in that area, it's not going to help on a WOT run ...... ? Right?

This last run at least looks better.

But you can see what the timing does from the moment I push the pedal.

If you switch to the "simple" timing. The Holley will take the idle timing, and ramp it up to WOT timing by 2000 RPM at the top of the table, which is WOT with zero vacuum.

But it does not give you any "vacuum advance" at idle, which is why I make my own timing tables and tweak them. Most performance engines like more timing at idle with low load.

Here is what the default "simple" timing looks like...(if you want, you can save a backup of your most current tune and try it). Keep in mind at WOT you are only going to be in the top rows. Although your MAP gets pretty low at high RPM, try it without an air cleaner once on a clean damp day and see if that changes. It's a free test...

1727700428938.png
 
Here is what the default "simple" timing looks like...(if you want, you can save a backup of your most current tune and try it). Keep in mind at WOT you are only going to be in the top rows. Although your MAP gets pretty low at high RPM, try it without an air cleaner once on a clean damp day and see if that changes. It's a free test...

View attachment 487628
Ha, just put a distributor in it!
 
Heath, how do you tune the timing? Are you trying to maximize the MAP? Or do you have other tricks. Also I forget where the setting is but how do you lock the timing so it doesn’t sway?
 
Heath, how do you tune the timing? Are you trying to maximize the MAP? Or do you have other tricks. Also I forget where the setting is but how do you lock the timing so it doesn’t sway?
I normally tune the WOT timing for best power or MPH at the track.

You can tune the timing at idle or part throttle for best MAP if you want.

Timing at WOT off the track is just by feel basically, and I am also generally more conservative then with the timing, you want to leave it the lowest timing you can feel any difference.

Of course dial it back and/or get better fuel if you ever hear any pinging.
 
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You have to have the computer online with the ECU while the engine is running, then you can do live tuning. You can literally change a cell and you can immediately hear if the engine likes it or not. Its one of the fastest ways to tune if you sit in the passenger seat while someone else drives and just tweak it. Make sure you download the tune from the ECU and then if you go "online" with the USB link while you run the engine you will see live tuning.

One time I had to tune my brothers supercharged 468 without an O2 sensor, because it was junk when we put the used EFI in it. This was original FAST EFI, no self tuning either, so he just drove around while I tuned it by sound, smell, and feel. Meanwhile my dad would follow us and say whether there was black smoke or not. Basically I made the base tune real rich to be safe and then backed it out until it was running real nice without black smoke.

It sounds to me like you are learning tuning yourself. You try something, see if it likes it, listen, smell, feel, and then if it likes it try a little more, if it doesn't try the opposite. Experience will get you tuning faster because you know which way to go and how much quicker, but its still basically the same thing.

The self tuning makes it really easy, because you can just change the target A/F ratio and let it try it if you want. But there is a large window where the engine will run fine, much bigger than you think.

Timing is much more critical, if the timing is off it can lose a lot of power or destroy the engine pretty quickly, although with a pump gas NA motor you should hear it (pinging) way before you hurt anything.

The acceleration enrichment is not self tuning, only the learn table, which is combined with the main table, is self tuning. Also, timing is not self tuning either, neither is cold start fuel, etc. It can only tune the learn table when the engine is warm and everything is stable and you are not changing throttle positions.
Isn't that what the USB link is,? Isn't that online?
I'll look again. When I have the USB link up is when I do the data logs. But that doesn't allow me to see that orange dot. :dunno:
If you have more traction in the back then you do in the front that will happen every time, it will just push the front.

Maybe you need skinny tires in the back only, ha ha.
With this fat azz truck it happens just about 60% of the trys I've made. And like I say, I still have 600-700# of stereo to go over the axle :doah:
Try going the same speed in a different gear, but you may need the same load, to me that sounds like driveshaft or tire balance, but its hard to say without being there. You need to determine if its only a certain speed, it sounds like it's not related to engine RPM. Is it related to speed or load?

If its in your floor and seat try putting the back tires in the front and see if it gets in the steering wheel.
I've tried it all over. Only does it in third gear at 59-65ish. On flat ground. Any other gear same speed, nope. Any other gear same RPM, nope. And I can feel it in the wheel. But it's no more prevalent there than the floor or my seat. That's why I wondered if it was an engine harmonic because of that particular combination of stuff being just the right load and speed....
If you switch to the "simple" timing. The Holley will take the idle timing, and ramp it up to WOT timing by 2000 RPM at the top of the table, which is WOT with zero vacuum.

But it does not give you any "vacuum advance" at idle, which is why I make my own timing tables and tweak them. Most performance engines like more timing at idle with low load.

Here is what the default "simple" timing looks like...(if you want, you can save a backup of your most current tune and try it). Keep in mind at WOT you are only going to be in the top rows. Although your MAP gets pretty low at high RPM, try it without an air cleaner once on a clean damp day and see if that changes. It's a free test...

View attachment 487628
I thought that simple/2D drop down was just for setting the values :doah:
Didn't dawn on me that I can leave it in one of the other and it's follow different. Lol.

Hi, my name is RON, first name MO :thumb:
 

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