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Old 09-04-2013, 01:31 PM   #76
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Did you mix the e85 with unicorn tears?
^^ Hilarious.. Im gonna recycle that one.
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Old 09-06-2013, 05:51 PM   #77
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its not a waste. i got protuned today with an aem cai and gained 40 whp from baseline running the cobb stage 1+ aem map. 221.2 whp vs 261.1 whp. take it for what its worth but there are definitely gains when tuned properly.
That's from the better tune. Not the intake.
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Old 09-06-2013, 06:42 PM   #78
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That's from the better tune. Not the intake.
^^^ ding
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Old 09-06-2013, 08:32 PM   #79
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That's from the better tune. Not the intake.
It makes more power with all the upgrades with a protuned.
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Old 09-06-2013, 10:59 PM   #80
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It makes more power with all the upgrades with a protuned.
I'd bet dollars to donuts that he'd be within 5 whp of the final number with the stock intake.
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Old 09-07-2013, 01:38 AM   #81
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I'd bet dollars to donuts that he'd be within 5 whp of the final number with the stock intake.
Qft....
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Old 09-07-2013, 02:05 PM   #82
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Here is a question for all the "intakes don't do crap" crowd. How did you come by this opinion? From reading on the internet?

Does anyone have good evidence, back to back tunes after installing an intake, showing little to no gains? To be any kind of legit, both runs tuned, not one canned tune vs a protune, but a tuned car, stock intake, vs a tuned car, cold air intake. Preferably same dyno, same tuner.

Because I have almost that after installing an AEM cold air intake, and the gains are substantial. Boost comes on earlier, hits target boost without overshooting, and holds target boost longer. I want to see some evidence that my situation is an anomaly, so post away.
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Old 09-07-2013, 02:13 PM   #83
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I bought one just to make other people mad, forget about "gains"
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Old 09-07-2013, 02:48 PM   #84
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I bought one just to make other people mad, forget about "gains"
Lulzzz!
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Old 09-07-2013, 06:57 PM   #85
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i will go out on a limb and guess that 95% of people reading these forums have no business modding a car the bank still owns.

and i'll go out on a limb and guess that 95% of people who mod these cars, have no business modding a bicycle or any other mechanical device
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Old 09-07-2013, 08:04 PM   #86
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and i'll go out on a limb and guess that 95% of people who mod these cars, have no business modding a bicycle or any other mechanical device
The truth is always the most hurtful way to say things. That was a good one!
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Old 09-08-2013, 02:42 AM   #87
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That's from the better tune. Not the intake.
i agree that most of the gains were from the better tune. the tuner said that stock engines with the stock intakes typically make 240-250 whp after the protune and that stock engines with some form of aftermarket intake typically make 250-265 whp. Again, take it for whats it worth as I have no dyno charts to prove it but I believe there is more to be gained than 5 whp. 10-15 whp on a $200 part is not bad as far as gains are concerned.
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Old 09-08-2013, 07:29 AM   #88
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and i'll go out on a limb and guess that 95% of people who mod these cars, have no business modding a bicycle or any other mechanical device
+ eleventy
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Old 09-09-2013, 08:52 AM   #89
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Here is a question for all the "intakes don't do crap" crowd. How did you come by this opinion? From reading on the internet?

Does anyone have good evidence, back to back tunes after installing an intake, showing little to no gains? To be any kind of legit, both runs tuned, not one canned tune vs a protune, but a tuned car, stock intake, vs a tuned car, cold air intake. Preferably same dyno, same tuner.

Because I have almost that after installing an AEM cold air intake, and the gains are substantial. Boost comes on earlier, hits target boost without overshooting, and holds target boost longer. I want to see some evidence that my situation is an anomaly, so post away.
there are only two metrics that are important: pre compressor intake pressure drop and intake air temperature.

we don't have a pressure transducer available pre compressor. we do have an IAT built into the MAF.

i have not seen any data that suggest any intake is BETTER at reducing IAT, in fact the opposite seems to be the trend.

precompressor pressure drop is important because any change here will have a proportional effect on the operating pressure ratio across the compressor itself (assuming target boost remains the same).

for example, assume target boost is 20psig mrp:

14.7psi atmos + 20psi MRP = 34.7psia MAP

with a "perfect" intake where there is zero pressure drop our inlet is 14.7psia and our outlet is at 34.7psia netting total PR of 2.36.

now assume an intake which gives a 1psi drop at peak mass air flow. our PR has become 34.7/13.7 or 2.53.

the end result is that the compressor is working harder, demanding more energy from the turbine. netting more energy from the turbine will mean:

delayed boost threshold
increased turbo lag
a smaller wastegate opening angle thus increased exhaust gas backpressure.

in this case, we could log the decreased performance via one simple metric: mass air flow.

another way to look at the above example is that operating with a 1psi precomp pressure drop vs 0psi is the same (in terms of turbocharger input energy) as increasing boost to 22.5psig from 20psig. obviously this scenario is a lot more attractive as it has a fairly high probability of netting increased torque.

so all we really have to do is compare mass air flow between intake systems. complicating this direct comparison is the fact that any worthwhile intake system upgrade will (imo) include a larger diameter maf tube, which means direct MAF comparisons are dependent on how well the tube is accounted for in the MAF translation table. additionally, anyone who discounts the insidious effects of turbulence/resonance around the sensor on the ability of the ecu to extrapolate valid MAF calculations is a fool.

instead of clammoring for "proof there is no difference," my opinion is that vendors selling products for profit via making specific claims of performance improvements should be the ones stepping up and quantitatively proving those improvements. they should also be offering MAF sensor translation tables that are generated on a flowbench.

but that's just me.
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Old 09-09-2013, 03:56 PM   #90
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Originally Posted by ride5000 View Post

precompressor pressure drop is important because any change here will have a proportional effect on the operating pressure ratio across the compressor itself (assuming target boost remains the same).

for example, assume target boost is 20psig mrp:

14.7psi atmos + 20psi MRP = 34.7psia MAP

with a "perfect" intake where there is zero pressure drop our inlet is 14.7psia and our outlet is at 34.7psia netting total PR of 2.36.

now assume an intake which gives a 1psi drop at peak mass air flow. our PR has become 34.7/13.7 or 2.53.

the end result is that the compressor is working harder, demanding more energy from the turbine. netting more energy from the turbine will mean:

delayed boost threshold
increased turbo lag
a smaller wastegate opening angle thus increased exhaust gas backpressure.

in this case, we could log the decreased performance via one simple metric: mass air flow.

another way to look at the above example is that operating with a 1psi precomp pressure drop vs 0psi is the same (in terms of turbocharger input energy) as increasing boost to 22.5psig from 20psig. obviously this scenario is a lot more attractive as it has a fairly high probability of netting increased torque.
This is exactly why a good intake is beneficial. Pressure drop at the intake is multiplied by the pressure ratio, a little bit better intake makes for noticeably better performance.

When specing out a hydraulic power system, the intake side of the pump is far more critical than the outlet. If the outlet piping has more pressure drop than you desire, then you can just run the pump a little harder. If the intake side has too much pressure drop, there is nothing you can do, pumps don't suck very well. Too much loss at the inlet and you can cavitate, then performance drops to zero. A turbo is not exactly the same as a hydraulic pump, but all the same principles apply (although a turbo will not cavitate).

I do not want to come across as an intake zealot, they are not for everyone, but I dislike the repeated spreading of misinformation. There is a recent thread that claims the stock intake is good up to 450 whp. I don't even think it is possible to hook the stock intake up to any turbo that is capable of making 450 whp. Yet this crap gets repeated so much everyone just knows it has to be true.

Last edited by northman; 09-09-2013 at 04:06 PM.
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Old 09-09-2013, 04:11 PM   #91
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there are only two metrics that are important: pre compressor intake pressure drop and intake air temperature.

we don't have a pressure transducer available pre compressor. we do have an IAT built into the MAF.

i have not seen any data that suggest any intake is BETTER at reducing IAT, in fact the opposite seems to be the trend.

precompressor pressure drop is important because any change here will have a proportional effect on the operating pressure ratio across the compressor itself (assuming target boost remains the same).

for example, assume target boost is 20psig mrp:

14.7psi atmos + 20psi MRP = 34.7psia MAP

with a "perfect" intake where there is zero pressure drop our inlet is 14.7psia and our outlet is at 34.7psia netting total PR of 2.36.

now assume an intake which gives a 1psi drop at peak mass air flow. our PR has become 34.7/13.7 or 2.53.

the end result is that the compressor is working harder, demanding more energy from the turbine. netting more energy from the turbine will mean:

delayed boost threshold
increased turbo lag
a smaller wastegate opening angle thus increased exhaust gas backpressure.
All of which will be small and almost unnoticeable. The real effect of the increased pressure ratio is more heat from compression, which is almost entirely removed by the intercooler, rendering the ultimate effect just about nill. That is until the pressure drop becomes huge and the turbo can't even hit target boost, or the Pr raises dramatically, at which point a less restrictive intake will be a benefit. However, this doesn't happen until beyond stage 2.

Quote:
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This is exactly why a good intake is beneficial. Pressure drop at the intake is multiplied by the pressure ratio, a little bit better intake makes for noticeably better performance.
No, it doesn't. If it did people would actually notice differences, dynos would show differences, etc., but they don't. Far too many people are thrown off by the extra sound and think that they feel more power, when they don't. Even more people say that they can't feel a damn bit of difference, which is the unfortunate (for the people wasting their money) truth.

Look at Cobb's dyno results for stage 1/2 with and without an aftermarket intake, the results are just about the same. Sometimes the tune with the intake shows a little more power, sometimes the tune with the intake shows a little less power, it's a wash.
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Old 09-09-2013, 04:25 PM   #92
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The real effect of the increased pressure ratio is more heat from compression, which is almost entirely removed by the intercooler, rendering the ultimate effect just about nill.
This is BS. You are saying a more effective turbo is of no benefit? Might as well just remove it then, I guess. Then you won't be heating that air up at all.

A turbo that is working more efficiently will heat the air up less, not more.
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Old 09-09-2013, 04:40 PM   #93
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This is BS. You are saying a more effective turbo is of no benefit? Might as well just remove it then, I guess. Then you won't be heating that air up at all.

A turbo that is working more efficiently will heat the air up less, not more.
What? I never said a more efficient turbo heats the air more, in fact I said exactly the opposite. A more restrictive intake raises the Pr for a given boost level, which increases the turbo outlet temps. Then you have the intercooler, which removes nearly all of that temperature increase and leaves you in pretty much the same place as the less restrictive intake (minus the slight increase in exhaust pressure due to the higher Pr).

While everything that ride5000 said is true, the difference is insignificant at the power levels we're talking about. It's like arguing the benefits of an 8" diameter downpipe vs a 7" diameter downpipe for stage 2, when a 3" one works just fine.

The stock intake works fine at near-stock power levels, it's not a restriction, which is why aftermarket intakes don't make a difference. Once you get the car to a point at which the stock intake starts to become a restriction, that's when those points that ride5000 brought up start to actually make a difference, and that's when an aftermarket intake is a worthwhile consideration. This point is NOT stage 1 or 2 though, it's much later, as evidenced by the numerous tuners who recommend staying with the stock intake, dyno results that show insignificant power gains (several of which are openly available on Cobb's site), and the boatloads of people who have installed an intake with the appropriate tune at stage 1/2 and didn't feel a single change in the car's performance.

The amount of evidence that an intake is not worthwhile at stage 1/2 is overwhelming. To ignore all of it is just willful ignorance.

Last edited by the suicidal eggroll; 09-09-2013 at 04:54 PM.
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Old 09-09-2013, 04:52 PM   #94
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All of which will be small and almost unnoticeable. The real effect of the increased pressure ratio is more heat from compression, which is almost entirely removed by the intercooler, rendering the ultimate effect just about nill. That is until the pressure drop becomes huge and the turbo can't even hit target boost, or the Pr raises dramatically, at which point a less restrictive intake will be a benefit. However, this doesn't happen until beyond stage 2.
i believe what you're trying to say is that a 1psi pre-comp drop is rather pessimistic with a stock turbo, because i'm pretty sure you know better than to say that every little bit DOESN'T help...
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Old 09-09-2013, 04:58 PM   #95
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i believe what you're trying to say is that a 1psi pre-comp drop is rather pessimistic with a stock turbo
I do believe it is. At 1 psi I think you'd probably see tangible benefits with an aftermarket intake. Maybe that point is at around 350-400 g/s, but it's not in the 200s that you get with a mostly stock car.

When is somebody going to stick a pressure sensor in their intake and start measuring this stuff?

I think people get so caught up in the N/A way of thinking, where a .5 psi drop in the intake is a .5 psi drop in the manifold And when you only have 14.7 to work with, that's a big drop in manifold pressure and a big drop in power. Things work quite a bit differently with a turbo in the mix. The boost controller bumps the DC up a bit, manifold pressure goes back to normal, and all you're left with is a slightly increased exhaust backpressure and slightly warmer IATs.

The reason why a forced induction car loses significantly less power at high altitude than an N/A car is the same reason why FI cars are less sensitive to restrictive intakes than N/A.

Last edited by the suicidal eggroll; 09-09-2013 at 05:12 PM.
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Old 09-09-2013, 06:36 PM   #96
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The amount of evidence that an intake is not worthwhile at stage 1/2 is overwhelming. To ignore all of it is just willful ignorance.
So where is this evidence? That is what I asked several posts up. My personal experience gave a positive impact, and I'm not talking butt-dyno noisemaker street racer crap. The engineering concepts are solid. I keep reading about all the industry-leading tuners that are gonna tell me I'm full of it, but nobody's posting. The tuner I use(d) is certainly an industry leader, I don't want to put words in his mouth by naming him on a public forum, but I can PM the info if it makes a difference. In a similar thread Dom at MPS went on record saying he sees about 15 whp with a CAI. Does he qualify as an industry leader?

On my car I saw more torque everywhere, in large part because the car spooled earlier and held boost flatter, longer. What is not to like about that?

And as for performance level, that was at a stage 2 VF level, I went from about 280 whp to about 300 with just an intake and a retune. Yes, the dyno sessions were not done the same day, so it is not a perfect compare. I've heard it said that gains of 10 whp or less are not really noticeable, and my gains where very much noticeable.

So where is the mountain of evidence? And note I've been saying all along cold air intake. I don't need to see a bunch of posts with short rams intakes that caused the temps to spike, I fully agree those are bogus.
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Old 09-11-2013, 02:15 PM   #97
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I bought the spectre filter at Autozone (K&N knockoff). A lot cheaper and from what I was able to glean from research, nearly as good. Got about 3K miles on it now. It's in the stock box on the car.
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Old 09-12-2013, 04:42 PM   #98
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The tabs on my stock airbox where the filter goes were broken off when I bought my car... a new box was as much as a Cobb SF intake so I bought the Cobb with their own box about the same time I bought my Access Port. I never logged intake temps, but more surface area on the filter and a box that uses the hood-ram is a great design IMO. I believe intakes will give you some gain, cold airs with long tubing I think will cause a little throttle lag - hence my preference for the Cobb and SF in general. I also really like the sound of the Cobb. Just an opinion.

And yes, I have my car pro-tuned on the E-85 and unicorn jet pack fuel.
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Old 09-12-2013, 05:04 PM   #99
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The tabs on my stock airbox where the filter goes were broken off when I bought my car... a new box was as much as a Cobb SF intake
you need to junkyard more.
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Old 09-12-2013, 08:09 PM   #100
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The tabs on my stock airbox where the filter goes were broken off when I bought my car... a new box was as much as a Cobb SF intake so I bought the Cobb with their own box about the same time I bought my Access Port. I never logged intake temps, but more surface area on the filter and a box that uses the hood-ram is a great design IMO. I believe intakes will give you some gain, cold airs with long tubing I think will cause a little throttle lag - hence my preference for the Cobb and SF in general. I also really like the sound of the Cobb. Just an opinion.

And yes, I have my car pro-tuned on the E-85 and unicorn jet pack fuel.
No lag on my aem cai. It helped get rid of throttle lag and is way more responsive.
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