Dyno tomorrow any guesses?

AdamBorz

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So in this dyno run, I see I need to tweak the MAF some, I'm commanding .85 Lambda and I get between 11.5 and high 10's especially around 3.6 volts upward. Every time the AFR dips into the 10's the engine shows some knock. I have it set to allow it to add 1 (to be safe) and is pulling up to 2. I see it pulls 2, adds some, but at the end around 5,442 rpms it starts to pull spark and the AFR drops into the 10's right after. I think it is seeing it richen up and pulls spark for some reason. At 5448 rpms it drops to 10.8 AFR. Lito has stoich set to 14.2, so at 14.2X.85= 12.07 AFR so my MAF tune needs to be leaned a tad if I'm looking at the correctly. So after the time tag 16:46:54 that is the 4th gear pull. You can see it adding spark, then starts to subtract and you can see the AFR dip into 10's after... unless it is knocking, which makes it run rich??? Actually, the more I think about it, probably is knocking which causes a slight misfire.... need to run the methanol and see what happens..... to be continued....................

This tuning stuff is pretty amazing :)

Edited to say it won't let me upload the log... uggg
 

JC SSP

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Just my humble opinion after 40 years of building and racing cars. I highly suggest you stop chasing number... not being a jerk but I have heard thousands of stories of 900+HP dyno pulls and 9-sec trailer queens that ran once and broke or never run to their full potential because so much is involved in getting the power to the ground and running consistently. 600HP at the crank and 530HP RW is very good for a first-time dyno & tune session. Again congratulations. :)

Just for the record, while you get things sorted out... you really can't hurt a motor with too much fuel (running rich), but you can damage a motor running too lean. I saw where you played with AFR but what was the final reading? Also, are you recording IAT and EGT? What did the plugs look like after the dyno run? What you should be concerned with is where the "knock" is occurring (RPM or Boost level)? Please do not use WM injection as band aid or to get more power until you get a good safe tune in place, then if you decide on WM then tune accordingly.

Consider posting your data logs here as there are some members that are excellent in tuning but for sure send them to Leto for further guidance.
 

AdamBorz

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I tried to upload the Hp tuner log said it’s the wrong extension to upload here. Lito doesn’t use hp tuner, (at least not with me) he uses SCT which is more alien to me lol. My wideband doesn’t plug into my SCT so I had sent Lito videos of it. The digital gauge is hard to see on video. I even had the frames per second turned way up.

Car is definitely running better, the knock is around 5000 rpms then goes away by time car is red lining
Just my humble opinion after 40 years of building and racing cars. I highly suggest you stop chasing number... not being a jerk but I have heard thousands of stories of 900+HP dyno pulls and 9-sec trailer queens that ran once and broke or never run to their full potential because so much is involved in getting the power to the ground and running consistently. 600HP at the crank and 530HP RW is very good for a first-time dyno & tune session. Again congratulations. :)

Just for the record, while you get things sorted out... you really can't hurt a motor with too much fuel (running rich), but you can damage a motor running too lean. I saw where you played with AFR but what was the final reading? Also, are you recording IAT and EGT? What did the plugs look like after the dyno run? What you should be concerned with is where the "knock" is occurring (RPM or Boost level)? Please do not use WM injection as band aid or to get more power until you get a good safe tune in place, then if you decide on WM then tune accordingly.

Consider posting your data logs here as there are some members that are excellent in tuning but for sure send them to Leto for further guidance.
Just t wanted to add, what I know about my car is what I’ve been told it has. Some of the stuff I can see, some I can’t. I see the KB, valve covers, methanol etc. I can even see suspension mods, headers, I can even see the clutch and driveshaft. What I can’t see I’m just being told it’s there. The reason I mention that is because of the mufflers, was told they were flowmasters, but they are the generic ones…. So if they aren’t what they were supposed to be
 

Dino Dino Bambino

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Well, the IATs are only 13-15*F above ambient so it seems that the heat exchanger coolant pump is doing a pretty good job at carrying heat away from the supercharger.
As far as I can see from those screenshots, everything looks good as far as the engine's concerned and the tune is safe.
There ARE two things that are working against you though: the high ambient temperature and the low barometric pressure. The former (with a consequently high IAT) is probably the reason why you're only seeing 17* of timing advance, and a 13.5psi barometric pressure alone will reduce the power output by 8% compared to sea level conditions.
 

StockishS197

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After a WOT run when the fuel cuts out (DFCO) it stutters coming back on. I mentioned it to Lito. Maybe that is because of the 25 he has it set at??

He also has DFCO set to instant so the AFR goes super lean even between shifts. Pops on slow down I don’t like it gonna change it back eventually to way it was.
Lito runs aggressive DFCO. It helps the RPM decay between shifts. I would mention it to him and he may be able to disable DFCO completely to eliminate the decel popping.
 

StockishS197

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Here’s another good baseline for a built 4.6 3v that is running about the same numbers as you. Dyno corrections alone can make the numbers skewed.

As long as it’s safe, let her rip.
 

AdamBorz

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Well, the IATs are only 13-15*F above ambient so it seems that the heat exchanger coolant pump is doing a pretty good job at carrying heat away from the supercharger.
As far as I can see from those screenshots, everything looks good as far as the engine's concerned and the tune is safe.
There ARE two things that are working against you though: the high ambient temperature and the low barometric pressure. The former (with a consequently high IAT) is probably the reason why you're only seeing 17* of timing advance, and a 13.5psi barometric pressure alone will reduce the power output by 8% compared to sea level conditions.
That is what I had the timing limited to… I was slowly adding it back but ran out of time and I wanted to see if the meth made a difference. I’m gonna make another appt to play with it more.

I didn’t realize that about the barometric pressure . Good info thanks.
 

AdamBorz

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Here’s another good baseline for a built 4.6 3v that is running about the same numbers as you. Dyno corrections alone can make the numbers skewed.

As long as it’s safe, let her rip.
Thanks, I’ll watch that for sure. I guess if I made double the horsepower at the crank from stock that isn’t too bad. I just thought she’d have a little more.
 

AdamBorz

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well after watching that video above, maybe the too rich condition is causing false knock. The hp kept climbing as I upped the spark.... we'll see when I run the meth and add spark what happens. I'll post back.
 

AdamBorz

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Ok so I was messing around with tune, tweaked the torque and inverse, upped spark, put max retard at -8
Spark. Took car for ride and tried to obey all the speed limits etc. I can’t post log so I took some screen shots. This is with methanol running. Basically I took shot of log in closed loop, then I slowly hit gas (did not just push to floor) as I’m not trying to grenande my engine. I fully expected it to pull all -8 spark…. But the grin on my face distracted me a bit from watching until later. If they don’t attach in order just look at the speeds to tell it’s the next clip…

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AdamBorz

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Okay, now that I have more time to compose, I think the dyno proves that methanol (I ran 50/50 boost juice) makes a big difference even if sprayed before a twin screw not after. I went in at 493 rwhp-468 rwtq and today after adding meth and tuning for it left at 610 rwhp and 592 tq… wow! That’s impressive I think, even if it was less humid today than the last session I don’t think it’d make that much of a difference.

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