[JimGnitecki]

I got my brand new Banks iDash DataMonster programmed to my needs yesterday, and did a clean WOT acceleration run from 30 mph to 90 mph recording key variables. The car is bone stock except for the Magnuson kit which was instaleld by Davenport Motorsports about a week beforehand.

The run proved to be very interesting (see actual attached datalog below).

Note that:

- The run was made at a location whose elevation above sea level is unknown, but it is on a route that is between locations that are at 3000 feet and 3557 feet, so it is at a pretty high elevation. I am not knowledegable enough to know how that affects things like boost pressure, but maybe someone who IS knowledgeable about such things can comment.

- During most of the run, the car's traction control and stability control were active, as the OEM Goodyear run-flat tires had inadequate traction, and I was afraid to try this without the electronic nannys protecting me and the car. Sorry about that. I know it screws up the results, but I need me and my car to both be safe. As it was, despite the nannys' efforts, there were still obvious traction issues for most of the run.

- The car was in 2nd gear at the time WOT was applied, and the 10-speed automatic did NOT shift down to 1st gear. That's interesting.

- Note how the ECU immediately retarded the timing a LOT, as soon as WOT was applied. Is this because Traction Control and / or Stability control commanded it?

- Note the climb in the fuel rail pressure

- Note that peak reported boost was 7.55 to 7.8 psi, with the UNaltered tune provided by Magnuson for my car. I know it peaked higher in the datalog during each gear shift, but that was presumably because the engine rpm was decelerating during the shift, and therefore unable to accept the boosted charge at the same rate as when accelerating?

- Note that despite GM claims of sub 100 millisecond shifts by the 10-speed, that was not true for the 2nd to 3rd shift, which took possibly as much as 200 milliseconds (the granularity of the Banks reporting was 0.1 second). However, the 3rd to 4th shift was FAST - under 100 milliseconds (the granularity of the datalogging prevents knowing the EXACT milliseconds.

- Note the IAT behaviour. IAT actually DECLINED during the WOT run.

- note that the car took 13.1 - 8.0 = 5.1 seconds to get from 30 to 90 mph. The car's weight for this run, including 16 gallons of fuel and 208 lb of me and my luggage, was 4012 lb, per a certified highway truck weigh scale. My performance modeling software predicted 6.26 - 1.83 = 4.4 seconds to get from 30 mph to 90 mph, and of course the modelled run had the advantage of having the car already fully transitioned to WOT by the time it hit 30 mph. So, the traction control and stability nannys actually only slowed the car down by about 0.7 second for the run, despite all the traction issues. Not bad!

Jim G



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[laynlo15]

I've tried running street tires on my 16 SS with a Magnuson and it's impossible even with low boost to gain any ground with traction control off. Same with my 2022 as its over riding my traction control at 10 psi. It tries to hold it back but just can't do it so I don't even think about taking it off.

[radz28]

Part of that timing retard could be TMA (I know it's heavy in 3rd for my car, but I don't recall how bad it is for 2nd, if any at all). You could play with that, if you were interested.

Some of the boost variance could be throttle moving around or cam timing changing. I've seen boost spiking on shifts, too.

In anything less than about 95* ambient temperatures, I see temperatures drop immediately, with throttle. The longer the hit, the better the drop. I noticed that before the IC change, too. Those Maggie intercoolers do a great job.

You might consider, if you haven't already, monitoring whatever Banks calls the Manifold Air Temperature channel (that's what HPTuners calls it). I think it's IAT3 or something. It's been a while since I've had my Super Gauge plugged in, but it's always pretty easy to determine which channel it is because it's so high, relative to the other IAT channels. That channel, though, will report what the ECM is extrapolating boost temperature, and that is what dictates intake charge spark retard. Sometimes that's helpful to see, if you're into watching data, like I am.

[JimGnitecki]

Originally Posted by radz28

Part of that timing retard could be TMA (I know it's heavy in 3rd for my car, but I don't recall how bad it is for 2nd, if any at all). You could play with that, if you were interested.

Some of the boost variance could be throttle moving around or cam timing changing. I've seen boost spiking on shifts, too.

In anything less than about 95* ambient temperatures, I see temperatures drop immediately, with throttle. The longer the hit, the better the drop. I noticed that before the IC change, too. Those Maggie intercoolers do a great job.

You might consider, if you haven't already, monitoring whatever Banks calls the Manifold Air Temperature channel (that's what HPTuners calls it). I think it's IAT3 or something. It's been a while since I've had my Super Gauge plugged in, but it's always pretty easy to determine which channel it is because it's so high, relative to the other IAT channels. That channel, though, will report what the ECM is extrapolating boost temperature, and that is what dictates intake charge spark retard. Sometimes that's helpful to see, if you're into watching data, like I am.

I'll add that IAT3 to my list of tracked variables!

I assume TMA is "torque management"?

Jim G

[radz28]

Yes, sir.

We're, also, actively trying to get Banks to add IPW and Spark Retard added to these products.

[Sillysspeed]

You should definitely get a dragy. Record elevation, da, 0-60, 330, 1/8, 1/4 etc etc. nice tool to make progress with. Definitely noticed much quicker shifts with sport mode on. Literally dropped a tenth in the 1/4 mile.

[JimGnitecki]

Originally Posted by Sillysspeed

You should definitely get a dragy. Record elevation, da, 0-60, 330, 1/8, 1/4 etc etc. nice tool to make progress with. Definitely noticed much quicker shifts with sport mode on. Literally dropped a tenth in the 1/4 mile.

I do have a Dragy that I used with my motorcycle. I did not realize that the Drag records elevation, but it makes sense, since it has access to the iPhone apps, and the iPhone does know the elevation! Thank-you.

I neglected to mention that my datalog above was done in Sport mode.

That 2nd to 3rd shift was slow not only in this specific datalog, but also in the other one done earlier.

Perhaps shift time varies depending upon what gears are being disengaged and engaged?

Or perhaps torque management of traction control being active has an effect on gear change time?

That slow 2nd to 3rd gear change would add as much 0.2 second to a quarter mile time all by itself.


Jim G

[MartinLe]

Originally Posted by radz28

Yes, sir.

We're, also, actively trying to get Banks to add IPW and Spark Retard added to these products.

I just emailed them, again, asking for progress.

[MartinLe]

Originally Posted by radz28

Part of that timing retard could be TMA (I know it's heavy in 3rd for my car, but I don't recall how bad it is for 2nd, if any at all). You could play with that, if you were interested.

Some of the boost variance could be throttle moving around or cam timing changing. I've seen boost spiking on shifts, too.

In anything less than about 95* ambient temperatures, I see temperatures drop immediately, with throttle. The longer the hit, the better the drop. I noticed that before the IC change, too. Those Maggie intercoolers do a great job.

You might consider, if you haven't already, monitoring whatever Banks calls the Manifold Air Temperature channel (that's what HPTuners calls it). I think it's IAT3 or something. It's been a while since I've had my Super Gauge plugged in, but it's always pretty easy to determine which channel it is because it's so high, relative to the other IAT channels. That channel, though, will report what the ECM is extrapolating boost temperature, and that is what dictates intake charge spark retard. Sometimes that's helpful to see, if you're into watching data, like I am.

I am under the impression that the MAT numbers are hard data coming from the sensor at the back of the SC?

[laynlo15]

I monitor mine when I log on HPT. Today I was logging for Mike as we are going back on the dyno tomorrow. My IAT's were in the 70s and MAT in the 80s. We may have to go back to the 98mm pulley in the cool air, I saw 184 kpa on the boost which is about 12 psi. Don't want it to be that high and I saw some knock in the log also which we hadn't seen in weather in the 70s. Today it was low 60 which is probably what I'll be running next weekend so need to be careful. Mike has the logs so I'm sure he'll want to make some changes also for the cooler air.

[laynlo15]

Mike looked at the logs and thought all was good. Getting some false knock, could be coming from the blower. I got it used and it has some coupler noise that could be causing it. All else was pretty good so we will dyno tomorrow make changes if needed. We have the knock sensor set pretty low to catch any issues we might see.

[radz28]

Sorry - off topic'ish for just a minute...

Originally Posted by MartinLe

I just emailed them, again, asking for progress.

SWEET!!! Hopefully that's the information they needed. It would be nice to have those values and alerts. I'd like to see when I'm getting any knock. I don't know why anyone wouldn't want that alert right off the bat.

Originally Posted by MartinLe

I am under the impression that the MAT numbers are hard data coming from the sensor at the back of the SC?

I've logged both channels while driving around, but the one that toohighpsi talks about, to my understanding, is the one the ECM is extrapolating. If what I read was correct, and I'm repeating it now is correct, it takes such things as coolant temps, obvious air intake temps, and other readings to extrapolate the MAT. The MAT value the ECM produces is what the ECM is looking at to see if a correction is necessary to keep from ignition knock. That IAT Base Spark Table is the table that dictates whether (or not) to add or subtract timing based off MAT/Airmass. I believe the breakout harness (which connects to the MAP Sensor plug I believe you're talking about) goes to Magnuson's alternate IAT (IAT2) sensor in the front of the blower. I believe, instead of taking the boost temperature reading from the MAP sensor, it will then take it from the sensor in the blower case. You don't HAVE to add/use a breakout harness like Magnuson's, and still use the OEM MAP sensor, but Magnuson's sensor is exposed to the blower airstream inside the case than where the OEM MAP sensor goes. I'm not sure how much that matters, and never checked, but I believe that's the convention behind it.

So - you CAN have readings from the OEM MAP sensor for MATs, or integrate Magnuson's IAT sensor (IAT2) into the MAT extrapolation. I doubt they would have gone to the effort to add the sensor, and then engineer a break-out harness and system to utilize it unless they tested it to be more effective than the OEM MAT sensor/location, but I wouldn't know for sure.

[JimGnitecki]

Originally Posted by radz28

. . . . The MAT value the ECM produces is what the ECM is looking at to see if a correction is necessary to keep from ignition knock. That IAT Base Spark Table is the table that dictates whether (or not) to add or subtract timing based off MAT/Airmass. I believe the breakout harness (which connects to the MAP Sensor plug I believe you're talking about) goes to Magnuson's alternate IAT (IAT2) sensor in the front of the blower. I believe, instead of taking the boost temperature reading from the MAP sensor, it will then take it from the sensor in the blower case. You don't HAVE to add/use a breakout harness like Magnuson's, and still use the OEM MAP sensor, but Magnuson's sensor is exposed to the blower airstream inside the case than where the OEM MAP sensor goes. I'm not sure how much that matters, and never checked, but I believe that's the convention behind it.

So - you CAN have readings from the OEM MAP sensor for MATs, or integrate Magnuson's IAT sensor (IAT2) into the MAT extrapolation. I doubt they would have gone to the effort to add the sensor, and then engineer a break-out harness and system to utilize it unless they tested it to be more effective than the OEM MAT sensor/location, but I wouldn't know for sure.

radz28: Is that breakout harness a "standard" part of the Magnuson 2650 kit? I am asking I just recently had a 2650 Magnuson kit installed and wonder if I have this feature.

Jim G

[radz28]

Originally Posted by JimGnitecki

radz28: Is that breakout harness a "standard" part of the Magnuson 2650 kit? I am asking I just recently had a 2650 Magnuson kit installed and wonder if I have this feature.

Jim G

I think it depends on the kit you buy from them. At least in the past, you could get pretty much just the blower itself, with no snout, hoses, belt, etc. Maybe it's changed now, but if you got hoses from them, I'm sure the breakout came with it, too. Based off my supposition - if you post pics of the engine bay, I could probably wager a fair guess whether or not you got the break out. You could also tell in the tune, because you have to rescale for the new sensor inputs.


Start around 5:27, in the video, for where they start talking about the MAT and IAT sensors


For a little more visual reference of the blower. You can see the sensor on the passenger's side of the blower case, on near the bottom.