$ub$onic
The Sticker Guy
Hum, I am wondering if it has to do with the filter. I am also running k&n and noticed a lower g/s. But I am also not sure if that is related to a slowly clogging cat
Mass Airflow The Grams/Second Thread (1.4 and 1.8)
- Thread starter krakenredbeard
- Start date
Hum, I am wondering if it has to do with the filter. I am also running k&n and noticed a lower g/s. But I am also not sure if that is related to a slowly clogging cat
laborsmith
New member
Running rich? My memory is from the time I started to notice power loss to the CEL that the cat needed changing was several weeks at the most, and as I always used premium I could not be sure. New cat and power returned to normal and no cels.
Laborsmith
$ub$onic
The Sticker Guy
I don't think it running rich but I am still running a stock 2nd cat with 30k ish of no primary cat. I could be wrong but I don't think the 2nd cat was designed for that kinda duty.
Anyways, the most I can get is 90 (ish) g/s.
My initial thought was the cat was restricting the flow, but now I am wondering if it's the k&n filter. I have a tune update to adj maf calibration.
brasschucker357
New member
ReeseLightning and $ub$onic, are you guys auto or MT? Elevation, humidity, and temperature affect air density. Air is less dense as elevation, humidity, and temperature increase.
krakenredbeard
New member
I'm def with you on this in average with trifecta full tune right at 20psi. Wonder if I got the advertised 23psi what I would be pushing g/s lol.
$ub$onic
The Sticker Guy
1.8 5 speed, 75 degree day with mid to high humidity. I think we are 1200-1500 feet
laborsmith
New member
I also do not think the 2nd cat was designed for that kind of duty.
In my case my first thought was the K&N cone filter because I had cleaned it just before noticing the power loss. Took it off and put it back on a couple of times, still down on power, took it to Neuner's, (pre my getting a code checker) expecting to be told I fouled the MAF and the code came back clogged cat. New cat and all was well. The main reason I now have an UG.
Laborsmith
ReeseLightning
New member
1.4T 6speed MT, Approximately 1,289ft elevation, idk what humidity % would have been earlier but it's 83% as I post this temp was 67 (according to the digital thermometer on the sonic).
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ReeseLightning
New member
4/6 gears around 4k rpm cause the UG alarm went off annoyingly at the time
brasschucker357
New member
Make another run up to 5500 and see where it peaks. Most of us are seeing our peak numbers between 5k and 6k.
ReeseLightning
New member
It's safe for me to go that high without a tune?
$ub$onic
The Sticker Guy
ReeseLightning
New member
With a stock tune isn't everything kind of working independently whereas with a trifecta tune everything is made to work together. Think of it like making simple syrup, water sugar and heat, with a tune the heat(stove burner) is adjusted in order to keep the solution from getting too hot or too cold.
brasschucker357
New member
The rev limiter will keep you from getting into the dangerous rpms. It's hard to hurt the stock engine on the stock tune. You'd have to downshift at too high of an rpm and float a valve, or run it without oil/coolant.
brasschucker357
New member
Ok, time for official results...
2013 Sonic LTZ hatch, aka Sonia
1.4t 6mt on STOCK TUNE
120g/s consistently, 3rd gear, anywhere between 75 and 85 degrees
124 g/s peak, 3rd gear, 80 degrees, 79% humidity
all runs are at 960ft elevation
Mods:
Modified stock air box with smooth tubing and K&N filter, zzp resonator only catback with second cat delete, boost bypass valve delete. Again, this is on the stock tune.
2013 Sonic LTZ hatch, aka Sonia
1.4t 6mt on STOCK TUNE
120g/s consistently, 3rd gear, anywhere between 75 and 85 degrees
124 g/s peak, 3rd gear, 80 degrees, 79% humidity
all runs are at 960ft elevation
Mods:
Modified stock air box with smooth tubing and K&N filter, zzp resonator only catback with second cat delete, boost bypass valve delete. Again, this is on the stock tune.
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ReeseLightning
New member
Well did another run and pleased with the results, my heart was pounding and loved the rush.
2012 LTZ hatch, 1.4T MT
107.2 g/s, @5.5k rpm, 4th gear, air temp was 73 (temp outside)
Mods, DDM intake
Just to clarify air temp refers to the temp outside or the air intake temp ?
2012 LTZ hatch, 1.4T MT
107.2 g/s, @5.5k rpm, 4th gear, air temp was 73 (temp outside)
Mods, DDM intake
Just to clarify air temp refers to the temp outside or the air intake temp ?
krakenredbeard
New member
Yep ambient or outside air.
Swordsmith
242hp/252 ft-lbs BNR EFI
I need to get better at reading this EFI tuner, but my last datalog shows a max airflow of 146.06 g/s from the MAF
Swordsmith
14 sonic LT 1.4t
146.06 g/s max using EFI's read on the MAF sensor
Mods:
ZZP intake w insert removed, Solo performance exhaust w hiflow secondary cat and resonator delete, forge bpv, VT tune. Bypass mod. VT clipped turbo, Bosh 42# injectors, Flexfuel sensor, running 93 octane 6.7% ethanol
Note this run showing 30% negative long term fuel trims. Was not doing particularly hard pulls, just doing some data logging to try and track down a stall when idle condition
Swordsmith
14 sonic LT 1.4t
146.06 g/s max using EFI's read on the MAF sensor
Mods:
ZZP intake w insert removed, Solo performance exhaust w hiflow secondary cat and resonator delete, forge bpv, VT tune. Bypass mod. VT clipped turbo, Bosh 42# injectors, Flexfuel sensor, running 93 octane 6.7% ethanol
Note this run showing 30% negative long term fuel trims. Was not doing particularly hard pulls, just doing some data logging to try and track down a stall when idle condition