Not unusual for those blowers to taper up on the boost up high. Danny thought it was more interesting that the 3.4 was tapering off, yet still climbing on the power.
Bigger blower = more power?
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Not unusual for those blowers to taper up on the boost up high. Danny thought it was more interesting that the 3.4 was tapering off, yet still climbing on the power.
Think I understand whats happening in the graph but can someone please confirm this. The 2.6L KB's are dark blue and red (15.05 psi & 16.60 psi) and the 3.4 Whipple is bright blue (18.44 psi).
While the 3.4 is make more boost it isn't moving as much air as the 2.6's are, rigth?
This coupled with the fact the 3.4 takes more power to turn all adds up to the 3.4 being down on power till 5.5-6k rpm, right?
While the 3.4 is make more boost it isn't moving as much air as the 2.6's are, rigth?
This coupled with the fact the 3.4 takes more power to turn all adds up to the 3.4 being down on power till 5.5-6k rpm, right?
The 3.4 is moving air inefficiently and consuming more power to do it. IAT2 was only 106 and had full 24-25 degrees of timing. I would need to build a gonzo 5.3 13:1 compression 3V to really reap the full 3.4 reward.
So, basically yes to your question
To add to the discussion on bigger = more power.
There is a thread on the 13-14 board about KB 3.2L's and a user posted there dyno graph.
5.8L with a KB 3.2L
Vs
(My car) 5.4L with 2.3L Gen 2R similar boost as 3.2L (16-19psi)
5.8L has full factory exhaust and the 5.4L has LT with OR X but past that its basically all the same. Comparing the two graphs the 5.4L/2.3L combo is making a little more/the same power as the 5.8L/3.2L combo until about 6k rpms. LT's help reduce cylinder pressure/boost so maybe this is an unfair comparison.
There is a thread on the 13-14 board about KB 3.2L's and a user posted there dyno graph.
5.8L with a KB 3.2L
Vs
(My car) 5.4L with 2.3L Gen 2R similar boost as 3.2L (16-19psi)
5.8L has full factory exhaust and the 5.4L has LT with OR X but past that its basically all the same. Comparing the two graphs the 5.4L/2.3L combo is making a little more/the same power as the 5.8L/3.2L combo until about 6k rpms. LT's help reduce cylinder pressure/boost so maybe this is an unfair comparison.
Let's try to keep things simple and not introduce so many variables. I'll try...
We've all heard that the internal combustion engine is basically a big air pump, right? The more air it uses, the more power it makes. So let's use my latest "upgrade" as an example, and remember guys, I tune. So.... I had a 2.3 TVS. I changed to a 4.2. The only other change I made were the injectors, which in themselves, make no power. I kept my CAI which did not need upgrading. The first thing I discovered on my very first datalog was my MAF Transfer Function needed adjusting... by a LOT. The engine was ingesting more air across the board, from idle to redline. More air, more power, right? In fact, my gas mileage also took a plunge...
So a larger blower handles more air at any given rpm.... more air, more power... same as a larger displacement engine. That's why the larger the engine, the less gas mileage it gets.... hmmm...
Am I wrong?
We've all heard that the internal combustion engine is basically a big air pump, right? The more air it uses, the more power it makes. So let's use my latest "upgrade" as an example, and remember guys, I tune. So.... I had a 2.3 TVS. I changed to a 4.2. The only other change I made were the injectors, which in themselves, make no power. I kept my CAI which did not need upgrading. The first thing I discovered on my very first datalog was my MAF Transfer Function needed adjusting... by a LOT. The engine was ingesting more air across the board, from idle to redline. More air, more power, right? In fact, my gas mileage also took a plunge...
So a larger blower handles more air at any given rpm.... more air, more power... same as a larger displacement engine. That's why the larger the engine, the less gas mileage it gets.... hmmm...
Am I wrong?
No, but you are underestimating the power the 4.2 is consuming. At 19 psi for both, the TVS would kick sand all over the 4.2.
I tried not to introduce boost into my logic because it is not related to volume. I'm talking volume.... More volume, more power, neglecting power consumption to spin the rotors. Trying to keep things simple and answer the question. Once we can all agree on my point, then we can discuss consumption, thermodynamics, etc....
Willie
Willie
There is no disagreement on whether a bigger blower moves more air, they do, I think many guys who purchase a bigger blower are surprised at the operating characteristics of the bigger blower, especially on a true 4.6 litre engine.
Certainly when considering all that is involved, yes I agree... I think we answered the OP's question though.
I datalog very frequently. My TVS used to make 19.4 psig. At that boost, my Load (V.E.) was 1.85. With my 4.2 at ~50 percent ETC Throttle, I make ~20 psig. My Load is over 2.40. Volumetric Efficiency is an indicator of power, so this tells me that the 4.2 is making significantly more power at 19-20 psig than the TVS. So I have to question your statement...
Willie
Gonna take a stab at this..
Let's say Case in point, 4.0 L blower vs 2.3 L ... Since we are compressing the air within the blower housing, and the housing becomes part of the equation in which the boost pressure is measured (intake manifold/Blower housing) since we have a bigger housing, we need more air in that housing to achieve a said boost pressure.. so more air is flowing through a bigger blower and into the cylinders at a given boost pressure.
Let's say Case in point, 4.0 L blower vs 2.3 L ... Since we are compressing the air within the blower housing, and the housing becomes part of the equation in which the boost pressure is measured (intake manifold/Blower housing) since we have a bigger housing, we need more air in that housing to achieve a said boost pressure.. so more air is flowing through a bigger blower and into the cylinders at a given boost pressure.
I would just refer back to my dyno chart, I was actually making more boost than the 2.6 and it was still kicking sand all over the 3.4. Only way to tell with your situation would be to overlay the charts. Your displacement advantage would probably make it a smaller difference.
But peak horsepower of the larger blower was greater than the peak horsepower of the smaller blower, correct?
It was, but I was revving higher since I have Jesel followers.
@Weather Man, what about the state of tune on each of the 3 engines ? I'm talking afr's, ignition timing, fuel ect. Any of the 3 have upgraded cams ? as all of that would affect the dyno # and wouldn't be a fair for comparison blower vs blower..
Edit, would also be interesting to see charge air temps and if they held steady enough to take that out of the equation.
Edit, would also be interesting to see charge air temps and if they held steady enough to take that out of the equation.
'07 - '09 had a 1.9L.
'10 - '12 had a 2.1L.
'13 - '14 had a 2.3L.
That's what I would've suggested. Also, bigger blowers don't come into their stride efficiency-wise until higher in the RPM band. The bigger the blower, the more RPM it needs to really do its work. When I installed my Whipple 2.9, my car actually felt slower on the bottom end than it did with the stock blower. If I remember, looking at the superimposed dyno graphs, the 2.9 was producing a little less HP at the very start of the run, then barely outpacing the stock blower until about 2K RPM. That was with the hyper-conservative Ford Racing 91 octane tune. My butt dyno tells me it's quite different with the VMP 93 octane tune.
The highest HP in the lower RPM had a stage 2 comp cam, the other had a stock cam and I have an aggressive bullet cam. They were on E85 and tuned with a safe a/f for maximum power. When Danny and I were discussing what was going on with my build, he dug back to find the 2 best comparable from the many many 3V's he has tuned.
I am actually on my 2nd cam (completely different), made absolutely zero difference, you could lay the dyno runs from both right on top of each other. The 3.4 simply didn't care.
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You sure about that 07-09 size?
If it was the Eaton M112, yes. If it was the M122, then it would be 2.1 also.
Well, since 07-09's came with the M122 and not the M112, there's the answer.
M122 is 122 cu in. 122 cu in = 1.99L = 2.0L
M112 is 1.8L.
The 2007-2012 have 2.0L blowers.
M112 is 1.8L.
The 2007-2012 have 2.0L blowers.
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