metroplex

First, *almost* anything downstream of the MAF does not have a direct impact/influence on the air transfer function (e.g. PI Intake manifold retrofit for a 4.6 2V with the NPI intake manifold). That means the Steeda zip tube should not have a noticeable effect on the transfer function, but it may be less restrictive or may simply be louder (hence the 8 ft-lb "increase" VROOM factor). Steeda's website states, "No additional tune is needed for this kit..."

However, modifications or alterations upstream of the MAF does have an effect. Drilling holes, gutting, going to a cone filter, etc... will lean out the AFR unless the transfer function is corrected.

I'm not sure what is going on with the Steeda CAI now that you mention the 90mm MAF. I have two transfer functions listed for the Steeda... one is just for the 90mm MAF, and the other is for the Steeda CAI kit. I suspect that the transfer function for the Steeda 90mm is just for the MAF itself (no airbox/filter, etc...) Remember that the MAF and airbox/cone filter must be calibrated as an assembly. Once you tack on that cone filter to the 90mm MAF, the transfer function WILL change.

FYI, the 03-04 Marauder MAF is a 80mm Ford factory MAF and the 98-02 Crown Vic uses a 70mm MAF. I have not measured the MAF housing for the 07 GT but the transfer function is similar to that of the Crown Vic.

Going to the BIGGEST MAF with the highest transfer function will not necessarily give you extra ponies unless you are pegging out your MAF sensors at 5V and need a bigger MAF. The biggest MAF may not an optimal transfer function resolution for your application.

tifo

That article is great! I wish they had tested the JLT II intake though as it might have been scored higher than the one tested. It's interesting that The JLT produced more power than the C&L but was rated lower for quality. I wish that each intake came with s 50 states street legal certifcate/sticker so I wouldn't have to take it off for smog...I guess I want my cake and be able to eat it too.

~Tifo

Emu Hunter

For some reason I was under the impression that most if not all of the CAI kits will pass CA/MA state inspections (these should be the toughest tests). Anybody know if that's actually true?

Second question about CAI kits that I have was regarding MPG changes. If I'm just cruising down the interstate at 70MPH, will I be getting the same (or negligible loss of) miles per gallon as stock? I gotta drive 100 miles per day, I'd like to know ahead of time if 'normal driving' with a CAI kit will result in an observable MPG loss.. (so I can save up gas money )

Glenn

mm/ff did a pretty good write up on many of the top intakes do a search at their website

69_gt500

Ide assume that a cai wont interfere with inspections. After i installed my CAI, I noticed no change in mpg on highway and city.

65sohc

IMO it is more important where you buy your CAI than which one you buy. You MUST get it from a specialty tuner such as Bamachips or Brenspeed. Otherwise you will get a generic tune that may generate the same peak horsepower, but will not have nearly the part throttle response that really makes the car fun during regular driving. When you get a CAI from one of these guys it's almost like getting the tunes for free since the Xcalibrator is loaded with three custom tunes instead of three generic SCT tunes.

Whitestallion06

I actually have the GMS CAI but i added a tune and replaced the granatelli MAF back with the stock one...i love the results although the fit is very tight and i have had to bend the box and i am hoping to find a little bit bigger filter the granatelli filter seems smaller that the JLT or C&L but nevertheless i think its the tune that makes the CAI your going to find very similar results with all the CAI its the tune that makes the difference.... ive heard that the JLT has better HP readings but only by 2 or 3 hp which isnt even enough for the dyno to really pick up ... bc dyno error is usually about 1 to 2

m05fastbackGT

The reason why the new Steeda inlet doesn't require any additional tuning ? is because it's located after the MAF housing..However on the other hand ? prior to the new Steeda inlet tube, the Steeda MAF housing was still using the factory inlet tube which was directly responsible for it's restrictive airflow and if you take a look at Brenspeed's test results ?? you'll see for yourself just how much of an airflow restriction there was.. it's also quite possible as you stated about not being sure which transfer function you had listed for the Steeda ? you mentioned having two transfer functions listed for the Steeda... one is just for the 90mm MAF, and the other is for the Steeda CAI kit. You also stated that you suspect the transfer function for the Steeda 90mm is just for the MAF itself (no airbox/filter, etc...) Therefore how can you claim the C&L air transfer function flows higher than the Steeda when you really don't know for certain which one you have listed ?? it's even possible that you may have the transfer function for the old Steeda 80mm CAI kit for that matter ?..Anyway, here's a copy of the test results..



C&L Street Intake
300.07 HP/310.28 Torque

Steeda 90mm
297.60 HP/309.7 Torque

The test was performed by making 3 pulls with each air intake. The numbers above are the average of the 3 pulls.

The steeda worked great but fell short above 5,000 rpm’s, most likely due to the lack of aftermarket inlet pipe.



Karen White
Brenspeed
574.594.9559
Visit us at www.brenspeed.com

metroplex

Which is what I said...

Since the aftermarket zip tube does not affect the transfer function, I am not sure how much of an actual gain you will see. Personally, I think it's not going to be much because my 4.6 2V V8 saw almost no gains going from a restrictive and twisty zip tube to a much larger and almost straight zip tube. I did notice the intake's sucking noise increased but otherwise it did nothing for power.

I tried to find the Steeda 90mm MAF for sale on Steeda's website, or at least some mention of a 90mm MAF for their CAI kit. I couldn't find one, so I am going to assume the transfer function I have listed for a Steeda 90mm is JUST for the MAF itself. The transfer function listed for the Steeda CAI kit is for the MAF + conical filter. Remember that in order to develop a transfer function, you need to benchflow the MAF and airbox/cone filter as an ASSEMBLY.

The Steeda #s aren't too bad, but like I said earlier, the C&L CAI's transfer function seems to edge out that of the Steeda CAI's transfer function. However the 03-04 Marauder's 80mm MAF and airbox assembly seems to be one wicked setup. I'm glad I bought it for my Vic when they were $140. It's a shame no one is making a low-restriction airbox and MAF kit for the Stang that takes paper panel filters.

m05fastbackGT

Remember that in order to develop a transfer function, you need to benchflow the MAF and airbox/cone filter as an ASSEMBLY. You're exactly right so therefore ? until your actually able to benchflow the MAF and airbox cone/filter as an assembly ??? How in God's name can you even claim that the air transfer function from the C&L flows higher than the Steeda kit when you just admitted in your own words that you haven't even tested the Steeda intake in order to make a side by side comparison ? all you've provided here so far are nothing but assumptions..The only real way to know for sure is to do a side by side test comparison between both the C&L and Steeda intakes...As for the Steeda website is concerned ? if your expecting them to sell you just the MAF housing ? they won't sell individual intake parts you either have to purchase the entire assembly or not at all.. Your only other option is to find another SCT or Diablosport tuner who will either sell you just the MAF housing or will loan you out the entire assembly..But then again, why would you just be interested in only the MAF ? when you clearly stated you would need the entire assembly in order to develop an air transfer function...

metroplex

I am looking at the C&L CAI's air transfer function with higher #/min numbers than the Steeda CAI's air transfer function (remember: these are CAI's and not the MAF by itself). Therefore if you managed to peg both MAFs, the C&L is "flowing" more air or at least is able to tell the PCM that there's more #/min of air going in than with the Steeda CAI. It's simple numbers and NOT an assumption. Refer to the attachment in a post prior to this one. Brenspeed's dyno shows that they final results are comparable between the C&L and Steeda, or at least the peak hp/tq.

Several SCT tuners have recommended I look at the C&L instead of the Steeda. I am sticking with the stock airbox assembly until someone makes an intake kit that meets my performance requirements (uses paper panel filters, larger MAF, optimized airbox lid), or basically a GT500-style airbox that is designed to fit into the GT and work with the stock inlet tube. I'd rather deal with a Ford factory MAF and airbox assembly than go to the aftermarket.

m05fastbackGT

Yes and Brenspeed clearly stated the results were directly responsible due to not having an aftermarket intake tube..So once again your assuming everything by what some graph is claiming..you don't know if this chart was updated after the Steeda upgrade or before ? another factor could very well be that whoever did the bench testing or whatever you want to call it ? perhaps their calibration #'s may have been off or maybe some other equipment related issue may have been a factor as well..The bottom line is this ? until you do your very own testing or have someone you know like Doug from bamachips or Brent from brenspeed do an actual side by side test comparison between the 2 cold air intakes ?? you have no real proof to back any of your claims..And I don't give a rat's tail how many graphs and charts you copy and paste on here..they don't prove squat, Have a nice day as well.. And FYI ?? the Steeda intake comes factory installed on both the Shelby GT-H and the 2007 Shelby GT which also includes the factory warranty..Therefore it's not considered as aftermarket equipment..

metroplex

That chart uses data directly based on the transfer function that is input into the PCM when you flash it with a dealer provided tune. Those are very recent as well. In other words, what you see in the graph is what your PCM sees when you flash it with the appropriate air transfer function, so I do not understand your confusion. Again, the C&L CAI air transfer function slightly edges out the Steeda CAI air transfer function. The 07 GT stock, 03-04 Marauder, 04 CVPI, and 98-02 Crown Vic air transfer functions were obtained from the Ford factory calibrations and as always, the air filter/airbox are used. The 03 Marauder airbox uses a PAPER panel filter and yet, it has much more potential than most of the CAI kits for the GT. I am sorry you feel that way about quantitative data.

If you believe the Steeda zip tube, which does not require tuning nor does it affect the air transfer function, will add 8 hp and 8 ft-lb of torque, then I have oceanfront property in Montana for sale.

m05fastbackGT

It's you who's confused..You've contradicted yourself by your own words time and time again so now you claim the zip tube has nothing to do with air transfer function when earlier you clearly stated.. Remember that in order to develop a transfer function, you need to benchflow the MAF and airbox/cone filter as an ASSEMBLY...So which of your quotes are accurate and which ones are not ??? Look I'm not going to continue debating back and forth over this trivial BS with you..it's more than obvious that your dead set against aftermarket cold air intakes for whatever reason you may happen to have ? and that's fine you're more than entitiled to you're opinions ? However that doesn't give you the right to push your opinions down the throats of those who may not agree with them ? The bottom line is were all grown adults here and are quite capable of making our own decisions and choices and it seems as though every time I visit these threads ? you always have something negative to post about aftermarket intakes and it's really starting to get old..Therefore if your looking for someone to argue with ? find somebody else..I've said all there is to say concerning this topic with you...

metroplex

The fact that you use question marks to end your sentences show you're a bit more confused. The zip tube, which is downstream of the MAF, has nothing to do with the air transfer function. Steeda acknowledges this by saying add'l tuning is not required for that tube. I think we've established this, yet you keep bringing it up trying to say I am wrong.

The C&L CAI's transfer function slightly edges out the Steeda CAI transfer function but only by a few #/min throughout the curve. I don't understand your confusion, and your tone seems to be rather argumentative without any basis. From your signature, I can see you are using the Steeda and are just trying to justify your purchase. I'm looking at the different air transfer functions I can program into my PCM based on what was provided by the manufacturers. Your opinions and extra question marks are not going to change that, and neither is the Steeda zip tube. And in case you still don't seem to understand the graph, it is a plot of flow (#/min of air) versus MAF voltage in terms of AD counts. These are not test results or dyno results. These are the transfer functions that go into your PCM so that the PCM can figure out how much fuel to inject to maintain the commanded AFR and correct this using O2 sensor feedback (if necessary).

One method of building a transfer function is by benchflowing the MAF and airbox/filter assembly (zip tube is not part of this test, so don't bother bringing it up), making sure that everything upstream of the MAF sensor element is in the right place as if it were installed on the vehicle. Voltage is applied, air is flowed through the intake assembly, etc... and the data points are established. Theoretically, if you max out the MAF (peg it out at 5V) you need to go up to a bigger MAF/intake assembly.

The GT500 transfer function will have a different resolution optimized for a supercharged engine and may or may not work well for a 300 hp 4.6 3V V8. However, there are 400-500 fwhp Marauders running the stock paper panel filters in the factory Marauder airboxes with the factory Marauder MAFs. There is some correlation between horsepower/torque and the air transfer function, but a lot more variables are involved besides simple air flow.

metroplex

Here's some math, that albeit is based on dated tech since it was implemented before FMUs were in widespread use:

Injector sizing:

Method 1
[Max MAF (lb/min) * 60 / 12.5] / (# of Cylinders * Duty Cycle) = lb/hr


Method 2
[Engine HP * BSFC] / (# of Cylinders * Duty Cycle) = lb/hr


Through some equation manipulation, you can correlate max #/min in the air transfer function with engine horsepower, but keep in mind that it will be too conservative with the FMUs and returnless fuel systems in modern EFI cars and again, there are other variables to consider.

HP = [Max #/min * (60/12.5)] / BSFC

Where BSFC = Brake Specific Fuel Consumption = Fuel Pounds per Hour / Brake Horsepower
For a racing engine, BSFC = 0.40 (low friction motor)
For a typical engine, BSFC = 0.50
Turbo/Supercharged engine, BSFC = 0.65

In the case of the Steeda CAI vs C&L CAI, a few #/min isn't going to make a huge difference. Buy whatever you want, because it is your car and your money.

65sohc

It is interesting to note that when I was in the market for a CAI last year I questioned a Steeda tech about the fact that their system used the stock rubber inlet tube. He said that in all their testing they had found no benefit in replacing it. Now, when almost no aftermarket CAI is using the stock tube, they have suddenly discovered 8 more hp with their new tube. Also of interest is the statement on the new MMFF DVD by JDM that at high rates of airflow the flexible rubber tube tends to collapse, causing significant restriction.

GT John

+1

m05fastbackGT

It's also quite interesting that JDM also claimed not just once but 3 times that the C&L street intake was 90mm in diameter when in fact it's no larger than 83mm...and here's the proof to back it up..
Hi all,

Lee from C&L here...

JDM is mistaken when speaking about our air intake assembly in the DVD. At one point, they refer to it as a 90mm, and then as a 95mm at another point in the video. Only our "racer" intake features a 95mm MAF section, with the "Street" kit coming in at 83mm. The "Racer" intake flows 1,070 CFM (see attached images), while the "Street" intake flows 1,003 CFM (about 7% less). MOST vehicles will not see a performance difference between the two kits, but we have received reports from tuners (such as Brenspeed) that they DID see a few more HP with the racer intake on higher-HP naturally aspirated applications with cam swaps.

We are supplying this DVD as a "perk" to those who purchase either of our intake assemblies for the '05+ Mustangs. With it, we have composed a little note that addresses these inaccuracies on the DVD. We have NEVER seen more than 265 HP (SAE corrected) on a Dynojet dyno, with most cars making 260-263. I have no idea why this vehicle posted such high stock numbers, but the "baseline" track testing seems to coincide with what you would expect to see from a 278 rear wheel HP GT with a good driver. And we certainly would not represent to any customer that the addition of our intake and tune on an otherwise stock '05+ GT would deliver over 292 HP at the wheels. Most typical cars will see about 283 HP at the wheels with either of our intakes and a proper 93 octane tune, with a peak gain of as much as 26-30 HP at 6,200 RPM. The "peak before versus peak after" numbers, which are measured at a lower RPM point (5,400-5,500) is usually in the 20-23 HP range...

Lee

GT John

Well, thats right from the horses mouth. Great post.

Man ya better get your flame suit on. There are a whole lot of guys here that will swear their putting 300+HP to the rear wheels with just a C&L and a tune.and have got the graphs to back it up.

I'm waiting for the new intake from FAST to be tested by Doug at Bamachips hopefully the testing will go good. Should see some info coming at the end of March.

Lee's numbers are right on.

Like some guys say. The dude running the dyno can give you any number you want to see. Especially if they sold you the add-ons.

The real test is at the drag strip. Not strapped down to some rollers.