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Fiesta ST Intake - Dyno Tested

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Location
Atlanta
#1
After installing our 2JR 3" catback and 2JR catted downpipe, I decided to do a couple runs with an intake. Now I dont think there is a true CAI available as all the ones I have found sit below the battery, behind the fans, in the engine bay. Not in the fender.

What we uncovered is what I suspected. In front of the car were 2, 1hp fans (floor driers). These move a ton of air and would probably simulate a 30-40mph drive.

At any rate - here are the results:

2JR 3" Catback
2JR Catted Downpipe
OEM Intake Box, with K&N drop in filter
RUN 13 - COBB AP, 93 OCT map

Run 15 - removed OEM Intake Box, added CAI - First Run

fiesta cai cold (2).jpg
cai in.jpg


Notice there was no change in hp or tq. Now, after RUN 15, which was the first run with the CAI. The intake temps shot up to 140deg. This is because of the intense heat that is in the engine bay. Immediately the power started to drop off. Our last run was 189whp. The TQ increase is with the CAI is only right at tip in when the turbo hits. After that, there is no change.

fiesta cai hot (2).jpg
cai in1.jpg
^^ Check out the intake temps - max of 140deg.

So then I decided to turn the CAI outside the engine bay and rerun the dyno. The intake temps stayed at 80deg or so and the HP returned to normal.

fiesta out cai (2).jpg
caiout.jpg
cai out1.jpg


Point being, a K&N Drop In not only makes the EXACT same power as a CAI, but its way more consistent in its power as it doesnt pull air from a hot engine.

So unless you can run a CAI in the fender, or build a box for it, or think of some other way to run cold air to it (and protect from the elements). The stock box w K&N is the way to go.
 


Colin1337

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#2
Weird, dyno results for my car netted me similar HP, but way more tq.and I'm only on the 91oct tune

What sort of dyno do you use?
 


rodmoe

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#3
Welcome Joe and good info .. Thanks

Also any Ideas how to smooth out that torque at 25.k to 4K ??
I know I asked this someplace else and here would be a great place to answer it ;) hehe [welcome]
 


OP
joe@2j-racing
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Thread Starter #4
Once I start cracking open the Cobb AP and do my own tunes, this should clear up.

Colin, we made 241tq in 5th.. I post 4th gear pulls. Hows your HP?

fiesta gearing (2).jpg
 


OP
joe@2j-racing
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Thread Starter #6
We were playing around with the different tunes - 93 makes more TQ, 91 makes more HP. I have V100. I will switch to V201 tomorrow.

fiesta (2).jpg
 


OP
joe@2j-racing
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Thread Starter #9
Ahh, catless DP! I'll dyno our catless DP tomorrow. Next time change the time from speed to RPM. For comparison purposes.
 


OP
joe@2j-racing
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Thread Starter #12
No dyno will be apples to apples, even the same type. Its mainly for comparison of parts on the same dyno, with all other factors reasonably constant. Its also a good idea to run a min of 5 runs to test heat soak, allow variations to work themselves out. Normally I run a total of 30-40 runs on a car. With Colin, he listed 2 runs (it was a dyno day) - but I'd be interested to see runs 3, 4, 5, 6, 7, etc.
 


Colin1337

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#13
Oh I know comparing dyno graphs is kinda pointless unless I dynod on the same dyno you did around the same time on the same day, that's the only real way to compare. I'm just posting for discussions sake haha

I wish I had runs 3,4,5 runs, unfortunately it was a max of 2 pulls that day. After I get a fmic, I'll either get a custom tune or run Cobb's stage2/3 tune and re dyno, hopefully with more than just 2 pulls.
 


Sekred

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#15
Looking at the dyno graphs these engine bay mounted Cold air intakes turn into Hot air intakes which leads to a decrease in torque, horsepower and throttle response once heat-soak sets in.
I really think these type of CIAs or HIAs need they own segment on "MythBusters" just to clean things UP!, once and for all.
Hang on, isn't there a Joey on MythBusters?, opps sorry that's Jamie.
 


Sekred

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#17
I have not seen that kit before. Your right about the heat shield, that's the best attempt so far. I wonder why they didn't make that intake hose one piece?.
 


BlueBomber

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#18
I have not seen that kit before. Your right about the heat shield, that's the best attempt so far. I wonder why they didn't make that intake hose one piece?.
The design is REALLY similar to the Injen heat shield configuration, just it closes over the intake tube itself for a better seal. The only problem with Injen's one is the space next to the battery cable- where hot air could enter in the original design, hence why I modified mine with a little extra weatherstrip to close it off - which largely seems to resolve the problem.

I was thinking that if we created a duct in the bottom of the heat shield to draw in from elsewhere, a-la Sekred's "SEKTUNE" DIY intake.
 


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Holmdel
#19
How did you modify yours. I'm a bit worried now. It's wierd though I swear after intake install I feel a lot more install throttle response.

-ry
 


BlueBomber

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#20
I added more weatherstripping to seal it up better by the battery, closed up extra holes etc. Seems to help with "heat" issues everyone ******* about. I spent less than $10 on materials, so it's not really a big deal. I also added a little square of tape over the wee hole in the thing and closed it up. Think of it as optimizing it further.

To get the absolute most out of the system, I think some sort of means of sealing more cleanly along the hood would slightly improve it and reduce the potential for higher temperatures - but I am sure the design of the tube itself significantly helps output.

I shot a video today showing what I mean - I live in sunny warm SoCal and my intake temps are always within +10*F of current ambient air temperature (ex: it's 73* outside. IAT is 83.5*F) - sometimes as little as +3 above ambient once the car is moving faster than say 20mph; most of my commute is stop and go as it is 100% city no highway and under 10mi each way.

So basically, as long as the car is moving the heat soak everyone complains about is really a non-issue, but I have taken steps to minimize the potential for heat to creep in when I'm stop-n-go.
 




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