Discussion in 'SN95 4.6L Mustang Tech' started by danno, May 18, 2014.
Spoke with kb and they recommended the 3 inch for 8.5-9 boost sooooo?! Trinity if I do get a cai that goes into the fender do I have to buy a new mai meter and tb or can I continue to use the stock? Also was curious how much hp you got with this setup running the stock intake. Last if I do run the filter in the engine bay until more funds are available will it be ok? Thanks!
Interesting. That link shows KB part number F1016 for the 4" tube for 96-04 GT with the OE 80mm MAF. I didn't know they made a 3" version of this intake.
As far as I know you can use the OE parts. The intake kit has a flange that bolts right up to the MAF. Just make sure you select the kit for the 80mm MAF as the 90mm MAF (aka the "Lightning MAF") will use a different flange.
With the stock intake & paper filter, stock exhaust manifolds and 4-cat stock downpipe, Comp 262AH cams and a 75mm TB and the conservative OTS tune from KB mine made right around 400HP at the wheels at ~9psi. I was hoping for a bit more but the stock intake is somewhat restrictive. I've since freed that up a bit and am probably making a bit more now.
TBH, I don't really care too much about peak numbers on the dyno. The SOTP feel of instant torque is awesome and the car's a blast to drive
Not ideal, but okay. I talk a big game but, er, that's what I'm running .
I have a shield around the filter so it's pulling most of its air from the giant hole in the fender apron rather than from the radiator fan wash. My plan was/is to get a KB intake at some point but I don't mod the car much anymore (am modding my STI nowadays...) so I'm in no rush.
KB is pretty adamant about their revulsion to sucking in hot air (e.g. read this) so it's obviously not ideal. Do what you can to avoid sucking too much hot air. You can even consider staying with the stock inlet -- right down to the snorkel -- and pulling cooler air from the fenderwell that way until you can get a proper cool air inlet setup.
Trinity, the 3" I was referring to was the pulley for the 8-9 boost kb said I would get. Also I hear ya about the getting cold air part. Just trying to run a safe but fun setup.
Well here goes everything, going to start it Friday after work and hopefully be done by weekend. Then trailer it to shop for tune/dyno. Thanks for all your insight, much appreciated!
I've got to laugh at that article just a bit. So 200 degree air charge + 200 degree recirculation air = 400 degrees?!? Yay! Kenne Bell has solved all of the world's energy problems!
I also don't understand why they have the air cooling when it goes through the bypass valve. It shouldn't change temperature at all.
Joking aside, there's lots of issues with their claim. #1 being that you will NEVER see 400 degree ACTs. Ever. My non-intercooled Eaton has never seen more than 230 or so.
#2 being that the "hot" air is passing through an intercooler. Yes, the final air charge temperature is proportional to the delta T (i.e. difference in coolant temp and air charge temp), and thus a lower initial air charge temperature would yield a lower final air charge temperature. But if the intercooler was worth anything at all, it'd be relatively efficient in getting the initial air charge down fairly close to the coolant temp. And once you get to a certain point, the air temps don't need to be any cooler to run more timing, at least not on a street car. In other words, 80 degree ACTs aren't going to net significant gains in timing over 100 degree ACTs. Etc.
#3, their claim of "1% horsepower per 10 degrees" is very misleading. The reason the SAE makes that claim is that a cooler AMBIENT air temperature (from an air mass up in the atmosphere) almost always is more dense and has more oxygen in it, thus increasing power. Changing the temperature of that ambient air mass after the fact (by supercharging, intercooling, etc.) does NOT affect how much oxygen it has in it. This is one of the biggest misconceptions in all of car racing/modding. The supercharger heating up the air does not decrease the amount of oxygen in a given volume; likewise, an intercooler (or water/meth) does not increase the amount of oxygen in a given volume. You might could make an argument that a cooler temperature would allow the blower to operate at a slightly better point on its efficiency map, but that'd be relatively insignificant, and would affect PD blowers the least. Bottom line: mass flow rate entering a system = mass flow rate exiting a system. In other words, filter intake = blower discharge, and the hot air under the hood = same oxygen as cold air in fenderwell.
This doesn't mean that air charge temps are irrelevant. A hotter temperature will be more prone to detonation. Therefore, a cooler temperature allows you to run more timing and/or a leaner fuel mixture, thus leading to more power. But it's important to make the distinction between power gains from a more dense air charge, and the gains from being able to run more timing. You eventually get to a point where you don't gain any power from adding more timing (same thing with leaning out the fuel), and once you approach / get to that point, a cooler air charge from intercooling or water/meth doesn't get you any more power.
Outside of all this theoretical talk, I don't see it making any significant difference in real applications. My car GAINED power moving from a fenderwell filter to a straight shot, likely due to the MAF being able to more accurately meter the air coming in. I also look at it this way: a straight-shot underhood filter is good enough for an OEM 660 horsepower GT500, 640 horsepower ZR1 corvette, and 580 horsepower ZL1 Camaro. I really don't understand why Kenne Bell insists it isn't enough for them. Might be the same reason those OEMs chose Eaton over Kenne Bell.
To danno, I'm thinking your stock MAF may or may not work. I could be wrong, but I was under the impression that the stock MAF runs out around 350 rwhp, and you'll certainly be above that.
Oh wow, I somehow managed to skip a couple of other ridiculous things in their "article".
First, they act like a fan can move as much air across the front of the car as actual air while drive. Psshh, not even close. That, in itself, invalidates their "test".
Second, they actually say that the best place to measure air temps is at "the entrance of the supercharger". That has to be worst advice I've ever heard. ANYONE who knows ANYTHING about tuning knows that the only temperature that matters is that entering the cylinders. You know, AFTER it's been through the compression of the blower and the cooling of the intercooler? If they really wanted "data", as they call it, they should measure the ACTs after the intercooler while driving down the road. I'll bet that the difference isn't even enough for the tune to pull any timing.
Good grief they are clueless.
With all due respect, these guys are one of the most popular supercharger companies on the planet. And they've been making and improving their superchargers constantly for longer than I can remember. They're one of the first names in superchargers and are probably one of the more reliable units out there. I wouldn't necessarily call them "clueless". Maybe you might have misunderstood the point they're trying to make (no offense to you). I didn't read the link yet because I don't have time...will read it tomorrow. But I would trust what they're saying with regards to the supercharger that they're manufacturing.
You're right, I shouldn't call them clueless. They are VERY knowledgeable and aware of what their doing with regards to.......marketing. Operation? Ehh.
If someone can challenge anything I've posted, I'm all ears to learning something new.
Sneakey, I read on their website saying hotter air = more boost, they say 10 degrees of hotter air = 1 psi of boost so if I was running a safe 9psi tuned boost with a straight shot intake ( my k&n) and it's 100 degrees warmer in my hood than my wheel well I would be putting 10 more psi boost/temp into the engine causing obvious problems associated with to much pressure/heat on my stock internals. Just saying what I read, so who knows, I don't. it would be neat to find documentation of inlet temp of fender air to hood air and see how much difference there is. My thoughts about it and how I understand how it works (could be wrong) wouldn't the twin screw (compressor) far exceed the pressure and or temp of what is coming into it anyway. I'm sure some one here can explain.
That really is stretching the truth quite a bit. To say that 10 pounds of boost at 125 degrees causes equivalent stresses of 15 pounds of boost at 75 degrees is......not really accurate. In reality, your EGR valve circulates VERY hot gases back into the cylinder (much higher than any air charge temps), and they actually decrease the combustion temperature. Besides, the combustion temperature is in the thousands of degrees. Think that 50 degree difference is going to make much of an impact on those temps and the stresses from those temps? Nope (assuming no detonation, obviously).
If I had a little more 'typical' setup, I'd love to do an actual side by side comparison, on the street, not on the dyno where you don't have any air moving. I really don't think it's even going to be a significant enough difference to even change the timing (which means it's pointless). Their #1 misconception is that the underhood air is really hot; truthfully, when moving at any significant speed, it's not. There's plenty of air being drawn in through the nose of the car, and exiting down beside the exhaust manifolds.
The second issue is that of the intercooler I brought up earlier. Let's say that there really is a big difference in fenderwell vs. underhood temps, and let's assume the blower adds 150 degrees to both situations. And we'll use Kenne Bell's own numbers of 70 degrees (which is ambient) and 200 degrees; that would mean the intercooler coolant is also around 70 degrees (ambient temp). An air-to-water intercooler is definitely able to get a 80% efficiency, so we'll use that. 80% means that it removes 80% of the temperature difference between the coolant side and air side from the air charge entering it. The equation is: air charge temp = (T air,entering) - [.8 * (T air-entering - T coolant)]
So, for the fenderwell example. Air charge entering intercooler is 220 (70+150). So we have 220 - [.8 * (220-70)] = 100 degrees. Ok, not bad.
Now the underhood. Air charge after blower / before intercooler is 350 (200+150). 350 - [.8 * (350-70)] = 126 degrees. Also not bad.
^^See what just happened? Those completely bogus numbers from KB (which I KNOW to be bogus because I've never seen anything CLOSE to 350 degree ACTs on my non-intercooled Eaton setup) only resulted in a 26 degree difference in actual air charge temps. 100 vs 126 on a street car is MAYBE worth a degree or two of timing, which MIGHT pick up 10 horsepower, and I seriously doubt any real tuner would try to risk that extra power out from numbers that close to each other. (And because of the reasoning I listed a couple posts above, we know that there's not any more oxygen content in the cooler charge).
So there you have it. Even with their own ridiculous numbers, you're talking less than 10 horsepower with an aggressive tune.
You are exactly correct. The blower is going to heat either of the two charges to a closer number than they were coming in, and then the intercooler is going to do a fairly good job equalizing out the output temps (as shown above).
And I feel like I should clarify: I'm not anti-KB at all. They make a great product that has served thousands of customers very well for many years now. But their "tech" is laughable, at best, and nothing more than marketing hype.
I hear ya man, im just new to all of this and would like to wrap my head around it a little more. I was just worried by what kb was telling me "oh if you run a open air intake i wouldnt even drive it, your gonna have problems" I was like wow, doing research i have seen many cars running this setup so I thought I would dive into it a little more. thanks a million for your knowledg and explaining, I just wanted to make sure it would be safe for my stock internals. Againg thanks man!
The short answer is that you will be just fine. However, I would say that it'd be good put some kind of shield around the filter. The stock housing actually works just fine. The way K&N does it, as well as JLT, are also perfectly fine. I personally would run a JLT. I picked up a decent amount of power going from an Ebay fenderwell CAI to a JLT RAI. Just a preference, though. I'm sure the K&N is just fine.
To each their own. But I personally wouldn't run an exposed under hood intake even on a NA car. We get some pretty hot days out here in NJ. Even on moderately cool days (like 70s), those intakes can easily over 90 degrees while the car is moving. And once it stops those temps can soar over 120 degrees in seconds. My intakes keep my IATs at ambient while moving. Once stopped I can see a 20 increase but that takes a good half a minute. And when I start moving again they drop right back almost instantly. And tha'ts NA. I couldn't imagine running that style intake through a supercharger on a 95 degree day in traffic. Again, you gotta do what you feel comfortable with. I wouldn't feel comfortable at all with that style. But that's just me.
2013 ZL1 Camaro:
Laguna Seca Boss 302:
Honda Civic SI:
Quick! Someone tell these OEMs that they're doing it wrong! These "lame" "hot underhood air systems" are terrible, will "expand your pistons", cause "metal scoring", and will "void the warranty"!!!1!1!!
I seriously can't understand how people believe this BS. Do they (Kenne Bell) realize just how ridiculous it sounds? I find it highly amusing that they scold people who 'modify' their systems because they "obviously don't know or don't care", while that is EXACTLY what they're doing by changing the originally equipped intake system.
Look, I'm not going to argue that a fenderwell intake might pull in cooler air in certain situations. But that air doesn't have any more oxygen in it than the air under the hood, and if the temperature difference seen by the IAT sensor isn't enough for the tune to add any timing, then you're not going to make any more power. Simple as that.
And you're fooling yourself if you think that MAF sensor is metering correctly with a sharp bend a couple inches in front of it from the fenderwell CAI.
Lastly, your post about IATs prompted me to pull up some datalogs of my car from 2008, when it was stock, from a night at the track. September 19, 2008, at 7:10, to be exact. Dragtimes DA calculator has the ambient temp at 66.2 degrees. Initial temp at the starting line, while not moving, was 88 degrees. By 20 mph, it dropped to 72 degrees, where it stayed +/- for the rest of the run. Next time I'm home, I'll grab my grandfathers 01 GT and do some driving around datalogging here in the hot summer, and see what turns up.
LOL, cool man, neat to see the numbers.
You're not showing the snorkels that virtually all factory inlets have that pull air into those closed boxes from cooler locations such as the fender well or in front of the radiator.
Even the GT500 intake is isolated from under-hood air directly by the elastomer seal around the top of the box that seals to the underside of the hood.
Actually, it will per unit volume. Cooler air is denser air and denser air has more oxygen in it than rarefied air.
Sneaky, you are completely incorrect AND you either didn't understand what I wrote or you don't know what a cold air intake actually is. Those pics you posted are very poor examples. Those intakes source air from outside the engine compartment. And the material they're made from resists heat. Even the open element Shelby intake has high heat resistance and is sectioned off once the hood is closed. In fact, the only reason it is an open element in the first place is for visuals. You think any vehicle or supercharger manufacturer is gonna recommend an intake that draws in engine heat? If you do then I don't know what to tell you. And if you personally think that any intake that draws in engine heat is a good idea then I hope you have money for an engine replacement. You can either do things the correct way, or you can be a hack and do things the wrong way. But like I said, that's just me. Do you.
Here is the intake I run on my SS. It draws air through the front grille but sits high enough that it doesn't ingest water when it rains. On any day, while the car is moving, my IATs are either exactly ambient or no more than 5 degrees hotter than ambient at the most. Of course this type of intake can't be used on all vehicles. But even my Mustang GT has an intake that draws strictly ambient air. I have a fenderwell intake on the GT. This is all just my personal style. Trust me, on a hot and humid day with a supercharged engine, you want as little engine bay heat as possible
I got that. No disagreement there. But my JLT intake pulls from the fenderwell, also. So does a K&N. But for some reason, that's not good enough for Kenne Bell.
Is that actually true? I may be wrong, and I welcome someone to set me straight, but I haven't had someone convince me of it yet. So density is mass/volume. The volume of the fenderwell or underhood is fixed, no? So the only way to increase the density of that air is to increase the mass. But we know we're not doing that. So therefore, my logic says the density doesn't change.
I think of this analogy. I go to a nitrous bottle in my garage. The volume is fixed (by the cylinder), and the mass is fixed (since it's sealed). I put a torch on it to heat it up. The temperature goes up significantly, but the density of the nitrous inside doesn't change.
See my reasoning? If you can point out what I'm missing, please do.
I still maintain that it doesn't make a significant difference on power output, especially on a car that has an intercooler that is going to largely even out the temps anyway, and when the difference in temps isn't enough to add any more timing.
I attached below a picture of a car I saw at the track today. Freakin' amazing car. 89ish notchback Fox. Exterior was super clean. Interior was real nice, and still very stock looking. Nice looking wheels and all. Motor setup was a fully built 5.4 DOHC. Big single turbo. This thing was a 100% street car, through and through. I'd buy it if it were for sale and I had the money.
Oh, and the car was running low 9's in the 1/4. On pump gas. On drag radials.
But eh, I guess he doesn't know what he's doing with that hot underhood air kit. (Not a dig at you, trinity. Only at KB.)
Trust me, on a hot and humid day (like today was here in NC), with a supercharged engine, my car runs FANTASTICALLY with a 'hot air kit' and ACTs north of 150 degrees. It has done so for over 5 years now. Here in a couple weeks, when I finish tuning my car, I'll have some low 11 second track runs to back that up.