FREE HORSEPOWER: Modifications to the stock CAI that help flow!

Did search a year ago as also noticed this, but I could find nothing unfortunately but can't modify the maf ID area, would mess up the flow and probably make it run bad.

Yeah, my plan wouldnt have messed with the MAF diameter or area. Simply removing the "lip" that seals that part of the filter out, was my plan.

To add, I was actually thinking of possibly adding a spacer the shape of the OD of the filter to raise the lid up 1/2" or so....

I have come up with a ton of ideas - I am definitely not short of them!

BMR Tech said:

Yeah, my plan wouldnt have messed with the MAF diameter or area. Simply removing the "lip" that seals that part of the filter out, was my plan.

To add, I was actually thinking of possibly adding a spacer the shape of the OD of the filter to raise the lid up 1/2" or so....

I have come up with a ton of ideas - I am definitely not short of them!

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Spacer idea is interesting as long as the lid still seals and no un-filtered air can get to the engine and as long as air box remains sealed giving the benefit of RAM AIR effect.

Do you think the mishi tube did anything or did you notice anything when fitting that?

What is your best 1/4 time now in this car and terminal buddy, your running E85 aint you? Whats that around 32 degrees spark?

[email protected]

That is with K&N, Mishi, Pypes Mufflers, rear 17" slicks (20s up front with 275s) and e85 fuel.

Tuning is by Palm Beach Dyno. The tune does not see 32. If I recall it sees about 30.5 up top, but Id have to check.

It made 418 SAE, and 430 uncorrected.

Very impressive indeed that is 470-480HP crank roughly, admittedly you have E85 and US cars have better headers stock than RHD ones but that is still hugely impressive power.

Surprised at your timing though consider many guys on good Octane 93/94 gas are seeing around 30 degrees spark also, I've seen as high as 32 on mine with no positive knock on a pull, but saying that was on GT 350 IM which is known for being able to run more timing.

Did Ken spend a lot of time fine tuning your tune or was that literally his off the shelf first attempt at dialling in your setup?

I know Ken is one of the best, but he is one very busy in demand man.

Great thread - enjoying it!

Thanks!

Gibbo205 said:

Very impressive indeed that is 470-480HP crank roughly, admittedly you have E85 and US cars have better headers stock than RHD ones but that is still hugely impressive power.

Surprised at your timing though consider many guys on good Octane 93/94 gas are seeing around 30 degrees spark also, I've seen as high as 32 on mine with no positive knock on a pull, but saying that was on GT 350 IM which is known for being able to run more timing.

Did Ken spend a lot of time fine tuning your tune or was that literally his off the shelf first attempt at dialling in your setup?

I know Ken is one of the best, but he is one very busy in demand man.

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Honestly? I bought the car, drove it home and loaded up the 93 tune from him. It was a little aggressive for me, because the 93 tune is what I use for a road course tune - so I had him dial it down to where peak timing is around 27 degrees. Last time I logged that tune, it didn't even reach 27 if I recall correctly.

The E85 tune is from the same time. It is the only tune I got from him, and has never been revised. It drives perfect and makes great power, so I have never considered asking him for any changes.

I have often considered putting 93 back in the car and running it in bone stock tune form with my mods on the hoosiers to see what it would run. I think that would be interesting!

BMR Tech said:

Honestly? I bought the car, drove it home and loaded up the 93 tune from him. It was a little aggressive for me, because the 93 tune is what I use for a road course tune - so I had him dial it down to where peak timing is around 27 degrees. Last time I logged that tune, it didn't even reach 27 if I recall correctly.

The E85 tune is from the same time. It is the only tune I got from him, and has never been revised. It drives perfect and makes great power, so I have never considered asking him for any changes.

I have often considered putting 93 back in the car and running it in bone stock tune form with my mods on the hoosiers to see what it would run. I think that would be interesting!

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Yes would be very interesting, I see Mishi claim 15HP from their tube, struggling how they achieve any gains without changing maf ID size, hence interested in your findings.

Are you worried to run more than 27 degrees timing on gas then? Or is that just because you can't guarantee the quality of gas in your area?

When I was on 350 IM with stock TB, Lund tune was always in the 29-31 degrees area, never had any positive knock and the car felt mighty strong and just wanted to rev for days. Just did not like gas pedal, over sensitive.

Hi there


OK I loaded on my JDM tune whilst I am stock might as well as I have it. When I previous ran the JDM tune I had the PMAS "no tune" CAI and I logged three runs.

So now I am back on the VERY SAME JDM tune, zero changes, on the stock intake with the mods (no need for tune change).

JDM PMAS "no tune" CAI: 43.23lbs flow rate
JDM modified stock air box: 43.76lbs flow rate


Of course its not back to back, so weather, air pressure can impact the flow rating, but in short it would appear that a modified stock air box can flow as well as the mighty PMAS.

Does this mean that the car is making more power if you have no tune, absolutely not because the stock Ford map will limit power to 410-415HP max, its designed to do this, but of course you improve your ability to always be running 410-415HP. The car certainly pulls crisper and responds much better to the air box mods.

Even though the PMAS flows no more, its maf sensor on the "no tune" variant fools the car ECU to adjust fuel mixture for the larger maf ID, this is why it makes a proven 10-15HP on a stock car with no tune.

However I firmly believe that two cars, both tuned by the same tuner, one with PMAS, one with modified stock air box would be making more or less identical power and well the PMAS is one of the best. In real world performance the stock air box could potentially edge it, particular on warmer days due to less heat soak and at higher speeds RAM AIR could help a touch too.

In short on a stock ish car then a CAI there is really no need for until it becomes a supporting modification, which does not happen until you upgrade intake or exhaust manifolds. So if your plan is just a tune and catback, save your money the CAI is really not going to benefit you, but the £300-£400 you save will buy you another pair of rear tyres to smoke.


In short a CAI is only worth it on a more highly modified car, bang for buck wise modifying the stock air box and just a tune is pretty much best value for money you can get and will see you around 450HP, maybe more on a custom tune with very good fuel.

Also just to add the JDM tune is essentially a canned tune, but with some Ford features such as no lift shift.

Watching spark is interesting, SCT/JDM/DS/Ford all claim massive torque increase of 40lb/ft at 1500-2500rpm.

Well now see how they do that, what they do is they ramp spark to 29 degrees in the 1500-3000rpm region, which is about as high as you want to go at such low RPM, torque bends rods, not all out HP. Once the car moves beyond 3500rpm timing is all over the place, 20-26 degrees up and down like hookers panties. Dangerous not really, the knock sensor will do its thing but it explains how they get the torque low down.

Whereas a custom tune is normally more friendly to the engine at low RPM, so 1500-3000rpm will sit around 25 degrees, but then build and hold steady as RPM increases, typically 26-27 in 3000-5000rpm and 27-29 beyond 5000rpm. So a more linear power increase, bit less torque down low but for more power up top and though I doubt any of the tunes pose any risk at all to the engines, a gradual increase of spark as RPM increases is also preferred because as like I say torque bend rods, especially if it comes on too quick at too low RPM.


Next plan is to check maf flow rates after the mishi tube is installed to see if by some miracle it does move more air, I will be amazed if it does, but at £120 I can accept that and it can go on the next car.


So to recap:
Stock: 42-42.5lbs
Stock with air box mods: 43-43.5lbs
JDM PMAS CAI: 43-43.5lbs
JDM with air box mods: 43.5lbs


Lets see if the Mishi tube can impact this.


Also if anyone wishes to log their car it is so easy to setup on the SCT and have a live display and you don't need to log as the SCT display will save low/max values so you can go for a drive to work, wherever, get to your destination and look at the low/max values for maf flow.

If interested post up and I shall attach the appropiate log files and make a video on how to do it.

Attach a log file, i'll run it through my COB and see what I'm getting through the airbox which like the GT modded one you've just done, is the same (Hopefully) and a high flow filter. See if it matches up with the US guys numbers :lol:.

Careful you don't tread on anyones toes... the CAI is their baby and makes power cuz a marketing team told them it did ;)!

Manders Mustang said:

Attach a log file, i'll run it through my COB and see what I'm getting through the airbox which like the GT modded one you've just done, is the same (Hopefully) and a high flow filter. See if it matches up with the US guys numbers :lol:.

Careful you don't tread on anyones toes... the CAI is their baby and makes power cuz a marketing team told them it did ;)!

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CAI's do make power, well some of them, by enlarging maf ID size to flow more but not all are equal.

The point is if you tweak the stock air box, throw some penny's at it, then it can perform just as well in short on a car running just a tune with the advantage of better drive ability, lower IAT's and RAM AIR, plus complete factory look.

Also remember some people like the look of a CAI under the hood, I won't lie my GT 350 setup looked way better than the stock air box under the hood.


I will attach a couple of log configuration files for you to try. Transfer them to your device using the laptop software, then load up gauges/datalog on your device and well I shall video the rest.

Infact Ken at Palm Beach dyno wrote an excellent guide to logging with a laptop:
https://pbdyno.zendesk.com/hc/en-us...to-Datalog-with-SCT-Livelink-and-SCT-X4-or-X3

You can download the config files, they are at bottom of page, but I shall attach them here for your convenience, one is for manual, the other auto.

Load the config files to your SCT/Ngauge, setup the gauges to display knock, maf flow and spark, this will allow you to see min/max values after a drive and keep an eye on knock value if your testing a new tune.

Yep, as I thought Cobbs gauges for me on a datalog then ! Cheers bud, i'll run one tonight and see what I get, obviously I'm running velossa/K&N and air raid intake tube for reference.

Manders Mustang said:

Yep, as I thought Cobbs gauges for me on a datalog then ! Cheers bud, i'll run one tonight and see what I get, obviously I'm running velossa/K&N and air raid intake tube for reference.

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You can only compare with EB's though. As a V8 for obvious reason is NA and more cylinders blah blah.

For example, your car will run much less spark advance due to be FI, if it was running over 30 degrees it would probably POP.