Dynoing out the myth of Intake mods: The Results
thanks SwivelHips, I appreciate it!
I'm currently running my custom lower plenum, 5/8 spacer, custom upper, z-tube, 06 rev up box w/ k&n drop in. I also matched the MAF to the air box. I need to go dyno again to see what the difference is.
I'm currently running my custom lower plenum, 5/8 spacer, custom upper, z-tube, 06 rev up box w/ k&n drop in. I also matched the MAF to the air box. I need to go dyno again to see what the difference is.
I found this on another forums. I think it's sorta relevant. Funny to see that it was posted allllll the way back in October 2006:
http://www.350z-tech.com/forums/856061-post12.html
http://www.350z-tech.com/forums/856061-post12.html
I'd be very surprised if an intake makes any power gains on a 350Z, unless you're getting a CAI pickup (and even then it'll be marginal). The intake design is already as high flowing as you're going to get without just having a gaping hole from the front of your car going into your intake plenum.
With a conical filter instead of a panel filter, you're changing the way the air flows through the AFM. This can possibly give it bad readings, and reduce power.
And since its the factory exhaust that's the biggest restriction on OEM, replacing the intake will do very little for the engine's willingness to rev. If anything, all that extra noise, the perception that you'll see gains, and the general lack of revability will give you the impression that its slower.
My suggestion would be to reset the ECU so it drops its saved values and it can relearn from scratch. I still don't think you'll see any gains, though.
And get at least a catback exhaust. If you don't touch the oxygen sensors in the cats you should technically be OK from a warranty perspective (its all just "dumb" pipe work south of the cats so there's nothing that affects the sensor inputs going into the ECU) but make sure you clarify with your dealer. I reckon the guy you talked to is an idiot, or been burnt by too many guys running aggressive ECU tunes or cracking the engine.
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With a conical filter instead of a panel filter, you're changing the way the air flows through the AFM. This can possibly give it bad readings, and reduce power.
And since its the factory exhaust that's the biggest restriction on OEM, replacing the intake will do very little for the engine's willingness to rev. If anything, all that extra noise, the perception that you'll see gains, and the general lack of revability will give you the impression that its slower.
My suggestion would be to reset the ECU so it drops its saved values and it can relearn from scratch. I still don't think you'll see any gains, though.
And get at least a catback exhaust. If you don't touch the oxygen sensors in the cats you should technically be OK from a warranty perspective (its all just "dumb" pipe work south of the cats so there's nothing that affects the sensor inputs going into the ECU) but make sure you clarify with your dealer. I reckon the guy you talked to is an idiot, or been burnt by too many guys running aggressive ECU tunes or cracking the engine.
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I really appreciate studies like this. Sometimes the results are so surprising and with numbers to back them up, there's no arguing. The methodology seems sound and consistent. Thank you for spending money and time! I'll paypal in a minute.
Regarding the stock numbers (baseline) you were running, this was with the z-tube and K&N filter - peak HP and TQ numbers, 237 and 219, respectively? If this is the case, I find it very interesting that the new OEM filter netted an astounding +8hp and -1tq. I would assume this was using a z-tube as well?
The port n' polished, upper and lower plenum, is beautiful
I may have missed this earlier, but do you feel the numbers would be slightly different if the avg. A/F ratios among the different intakes were more consistent with one another? It's just your one comment stuck out to me which re-iterates, imo, the importance of proper tuning and MAF calibration.
Regarding the stock numbers (baseline) you were running, this was with the z-tube and K&N filter - peak HP and TQ numbers, 237 and 219, respectively? If this is the case, I find it very interesting that the new OEM filter netted an astounding +8hp and -1tq. I would assume this was using a z-tube as well?
The port n' polished, upper and lower plenum, is beautiful
I may have missed this earlier, but do you feel the numbers would be slightly different if the avg. A/F ratios among the different intakes were more consistent with one another? It's just your one comment stuck out to me which re-iterates, imo, the importance of proper tuning and MAF calibration.
Now my engine was already tuned so on the stock box the AFRs were around 12.8 where they should be; when we added intakes on my setup they got very rich. On a stock tuned VQ35DE the AFRs would be in the high 13s and I think it’s possible that the intakes causing the AFR’s to drop into the high 12’s would show a power gain
I really appreciate studies like this. Sometimes the results are so surprising and with numbers to back them up, there's no arguing. The methodology seems sound and consistent. Thank you for spending money and time! I'll paypal in a minute.
Regarding the stock numbers (baseline) you were running, this was with the z-tube and K&N filter - peak HP and TQ numbers, 237 and 219, respectively? If this is the case, I find it very interesting that the new OEM filter netted an astounding +8hp and -1tq. I would assume this was using a z-tube as well?
The port n' polished, upper and lower plenum, is beautiful
I may have missed this earlier, but do you feel the numbers would be slightly different if the avg. A/F ratios among the different intakes were more consistent with one another? It's just your one comment stuck out to me which re-iterates, imo, the importance of proper tuning and MAF calibration.
Regarding the stock numbers (baseline) you were running, this was with the z-tube and K&N filter - peak HP and TQ numbers, 237 and 219, respectively? If this is the case, I find it very interesting that the new OEM filter netted an astounding +8hp and -1tq. I would assume this was using a z-tube as well?
The port n' polished, upper and lower plenum, is beautiful
I may have missed this earlier, but do you feel the numbers would be slightly different if the avg. A/F ratios among the different intakes were more consistent with one another? It's just your one comment stuck out to me which re-iterates, imo, the importance of proper tuning and MAF calibration.