What Entry Level Supercharger For 03 Gt

Discussion in 'SN95 4.6L Mustang Tech' started by 03GTGal, May 1, 2014.

  1. Ummmmm....yeah, nice try. The stock Eaton M112 and The Vortech T-Trim aren't exactly the same class of supercharger by any stretch.

    A Vortech S-Trim would be a lot more even comparison with the Eaton M112, but of course there wasn't one offered in their "unbais testing". :rolleyes:

    Ironically, even still the Eaton stayed ahead of the much bigger T-Trim in torque production until 5,250RPM, where the Vortech's deeper breathing nature finally took over. Curious to note at 2,500RPM the Vortech was only seeing 1.9psi vs the Eaton's 12.3? As far as street driving goes....well, by 5,450RPM, you're already about 80% through your usable RPM range....so you're really gonna have to leg that one out if you want to let that T-Trim shine.

    I did however noticed that you conveniently left out the the Kenne Bell 2.2L (which even itself has now been outdated for years) vs the Vortech T-trim comparison that also went head to head in this showdown.

    The horsepower and torque peaks between these two similarly size blowers are what was outlined by Will and myself, within 21hp of one and other (which in the 700hp range , is pretty much a wash really), but the Kenne Bell makes a much fatter torque much lower and longer in the power band with a higher peak to boot. By the time that 21-extra horsepower the T-Trim is noticed, the race is over and the Kenne Bell equipped car is on it's way back to the pits!

    *they didn't do a Vortech Vs Kenne Bell comparison, so you'll just have to look at the two and compare*


    And since were're taking excerpts from this article, I was particularly fond of this one...

  2. I guarantee you that the PD blower car will win. You are correct that most of the race is spent in the upper rpm range where the power levels are similar. I stated that earlier. But considering both cars start at 1500-1800 and have to get to that upper rpm range (4500ish), the PD blower is going to do that MUCH quicker. Probably a couple tenths quicker. And if you've raced any at all, you'll know that going down by 2 tenths in the first 100 feet without having any power advantage beyond that is going to equate to a fairly big butt whooping. The old adage of 'one tenth in the 60' equals two tenths in the 1/4' is pretty darn accurate, and losing by 4 tenths to a car that made the same peak horsepower is pretty bad.

    Beat me to it. If we're gonna compare a T-trim or D1SC, we need to use a 3.4 Whipple or 2.3 TVS or 2.8 KB. And I'd bet the power numbers at the same boost are comparable.
  3. I chose the KB 2.6 two valve kit (someday I may even get around to installing it.) I wouldn't go with the 2.1. As soon as you build the bottom end, the 2.1 becomes a really expensive paper weight. The 2.6, or 2.8 for that matter, they have both for 2v's, will grow with you as you build the motor. The 2.1 is maxed out with the stock bottom end. Went that route due to my early years of hot rods. I like the 455 Olds. Put it in gear and your already right at 500lbs/ft of torque. I'll stick with the bottom end grunt and gear my car accordingly. Same can be said for centri's too, just need more gear to get it to accelerate into it's power band quicker. Trouble with that is living with 4.+ gears all the time.
    #23 jetmech807, May 9, 2014
    Last edited: May 9, 2014
  4. A stock stall auto GT can launch at 1500-1800 this is true. But at that RPM, the centri will already be making boost. Maybe not as much boost as the PD, but def enough to keep them close. And without slicks the auto equipped PD blower is just gonna spin the tires anyway. I'm not arguing over who will win because I don't care which one will win. I'm saying that if person A had a otherwise stock auto GT with a PD blower against person B with an otherwise stock auto GT with a centri blower, then neither will walk away from the other. And you can't be biased. You're making it sound like the PD blower totally destroys the centri blower on the low end AND still is equal up top. This is not true at all. The centri makes just as much more up top as the PD makes down low. On 2 similarly equipped cars, neither one will walk the other. Because if PD blowers did, then centri blowers would be extinct.
  5. ...and you would be wrong.

    Absolutely, positively 100% not. An S-Trim Vortech doesn't start seeing any boost or power increase in the standard 8psi HO trim until nearly 3,400RPM. To think they start making power at1,500-1,800 RPM is absurd. These blowers need CFM to pressurize the intake and need to spin hard and fast to make boost in order to do so...and that just isn't happening at your basic entry levels. Even pullied, you're pushing your luck to get one to come on much below 3,000RPM.

    That's just the nature of the beast.

    A positive displacement blower moves 1 measured displacement (M112 moves 112ci...a 2.2L KB moves 2.2L) per single revolution. That is why the lower intake is pressurized almost immediately. The difference being, that compression takes place in the lower manifold with an Eaton and takes place within the compressor itself with a twin screw.

    To that I say.....465lbs ft of torque (350lbs ft of which was made at 1,800RPM), plain old drag radials (not slicks), 4,200lbs total weight, 4R70w trans (that was having issues that day I might add) with a Mercury Marauder converter, 3.27 rear gears and an 85-degree, high humidity day. Seeing 8-9 psi of boost.

    View attachment 115921

    The same cars, with the Vortech's under hood, making 8psi (standard HO kit), with the same class rear tires were running mid/high-13's that same day. The only Vortech powered car there that was faster than me that day had a huge host of mods, an S-Trim pulleyed for 12 psi spraying water/methanol, 4.10 gears out back and a 5-speed manual swap. He was running 11.80's.

    ....and he got beat by an auto equipped T-Bird running a Whipple 2300AX making almost 20PSI and running mid-10's.

    Fast forward to :55 seconds. Does this 4.6L SOHC sound like it's tapering off and falling on it's face at the top end?!? :scratch:

    View attachment 115922
    85rkyboby likes this.
  6. Oh Jesus. Ok lets agree to disagree. Im not "blower-loyal" enough to continue in the argument. Ive done it more times than I care for and have no energy to continue. Boost is boost....and boost FTW!

  7. lol....hey man, you're the one who wanted to start posting up examples to illustrate your point. It's not my fault they were flawed. :D
  8. So you're using your one example as the standard for all PD and centri blowers? There have been many times in shootouts, comparisons, etc, that centri blowers have gone up against PD blowers on every type of car in everything from bench racing to magazines to online videos to Youtube. And I'm telling you that PD blowers are not hands down as superior to centri blowers as you're making them out to be. Heck, they aren't even superior at all. A car with a PD blower can be built to take advantage of how it makes power. And a centri powered car can likewise be built in similar fashion. But out the box, a PD blower does not blow away a centri blower. They don't. And I don't know where you guys are getting the information that they are. They never have. Maybe one can edge out the other depending on driver or other mods...but not stock to stock.
  9. You're putting words in my mouth. I never stated that one was superior to another. Only that out of the two systems, provided the blowers and mods were sized and matched accordingly, the PD blower would provide a broader horsepower and torque curve with similar top end figures and thus an as fast and generally faster car out of the gate. Seen it dozens of times....done it dozens of times.

    Quite frankly,most centrifugal systems just can't compete at standard street (5-9psi) boost levels. You gotta pulley the centi's and gear the cars to make them move....otherwise the race is over, before it starts.

    Agree, disagree it really doesn't matter to me. The street and track results speak for themselves. Where the 4.6L modular is concerned, they don't generally do as well with centrifugal as they do with PD blowers without additional mods to even the playing field. The displacement is too small and the internals are too weak.
  10. banger, perhaps I misunderstood what you were saying. I agree with you that a PD blower will make more low end hp and tq thus giving it the jump on a centri powered car. But it seemed to me like you were saying that the PD blower makes more hp and tq down low AND up top. My bad if I got that mixed up. To be clear, I'm just saying that the PD has the advantage from the take off. But once that centri gets into boost it will start to catch up. And I'm saying that neither one will walk the other in a quarter mile. The PD might start out faster, and the centri might start to pull harder, but at the end of the quart, both will be just about neck and neck.
  11. Agreed. Anyone who says that a PD pulls just as hard up top as a centri is incredibly mistaken
  12. Aaaand......that's not true. Take a BONE STOCK 99-04 GT, put a Vortech on it pullied to a max 9 pounds of boost. Then take the same car, put a 2.1 Kenne Bell on it, and they will make VERY similar maximum power numbers. I'd venture to say that both cars would make within 10 horsepower of 370 rwhp or so. I mean, heck, Vortech and Procharger rate their 2-valve setups at 402 and 403 brake horsepower on 8 psi, respectively, while Kenne Bell rates theirs at 420 brake horsepower. Granted, the Kenne Bell numbers are on a very aggressive tune, it'd be right in that 400 horsepower range if dialed back to a safe number.

    Wrong. What does every person who is serious about racing do with a centri-powered auto car? They put a big converter in it. Why do they do that? Because it doesn't make enough torque to properly get it off the line. My car would easily cut 1.8x 60's on street tires, and that was power limited, not traction limited. The idea that a positive displacement blower car has major traction problems is a myth.


    Also (pretty much) true. Within a few percent.

    Not true. The PD blower will make upwards of TWICE as much torque down low, while the centri blower might be 5% more efficient at the tip top of the rpm range.

    From a roll, or with a big converter, or a clutch that'll help get the rpms up to begin with, yes, you are correct that it'll be a wash either way. But if two stock converter auto cars make the same peak horsepower, but one of them has a couple hundred extra foot pounds of torque at 2000 rpm, I GUARANTEE you that it will walk the other car from a dig.

    Umm....they are. There's not a single OEM that uses a centri blower that I'm aware of, and can't think of any that ever have. There's a reason for that. Think about it.

    Don't get me wrong. Centri blowers have their place, and work well when you're pushing a LOT of boost making BIG power. But let's face it: the REAL reason that a lot of people choose a centrifugal blower is their [typically] lower cost. The other reason is the incorrect assumption that PD blower cars make getting traction impossible, and that for some reason a setup producing less power is the solution to that, instead of fixing the traction and/or gearing problem.
  13. Well if that's your line of thinking then we both apparently are not gonna agree. So...no sense in debating this any further.
  14. My "line of thinking"? Nothing in my post is my opinion. Quote ONE thing in my entire post that is not factually correct. And I don't mean something that you think is incorrect, but something that you have proof of. Facts, data, reasoning, logic, etc.. Those kinds of things.

    Here, I'll start. Take a look at the "Dyno Thread" here in our forum. RWHP numbers I'm seeing from mostly stock 4.6 cars with 8-10 psi from a centri:
    375 rwhp
    347 rwhp
    370 rwhp
    412 rwhp (appears to have a spike at the end of the pull, real numbers would probably be 390-395 rwhp)
    362 rwhp
    351 rwhp
    428 rwhp (full bolt ons, and a bit more boost than the other cars, as well as an STD correction)

    And numbers from positive displacement blowers in the same boost range: (I also pulled numbers from this thread on SVTP):
    366 rwhp
    409 rwhp
    361 rwhp
    417 rwhp
    385 rwhp
    410 rwhp
    403 rwhp
    397 rwhp

    See a pattern here? Neither one is making significantly more power up top than the other (although an argument could be made that the Kenne Bells are actually making more power up top, but that's marginal and unimportant for the point I'm trying to make). Which is what GB and myself have said for several posts now. But even you agree that the positive displacement blower makes significantly more torque down low, as much as 100% more in a lot of cases. And in two cars that HAVE to go through that rpm range, the one making more torque is going to go through it more quickly, and is therefore going to win the race.
  15. Oh, this reminds me: Nightfire, did you ever get your car on the dyno?
  16. Dude, calm yourself. There is no need to take that tone. I'm not arguing with you and I'm not gonna be argued with or spoken to like such. I know my stuff ok? And I know what I'm talking about. Just like you do. And I'm not gonna be spoken to as if I'm just talking to be talking. And my statement when I said "your line of thinking" was a figure of speech. I don't care enough about this to go on and on arguing about it. So like I said before, we are not gonna agree and thats that. Now I hope there is enough mutual respect between us for us to chalk it up to a simple disagreement. But regardless, I'm not gonna go looking up every example I have that points to the exact opposite of your data. We both have sufficient knowledge and data to believe what we will. And besides, I'm talking about cars with similar mods. How do I know what mods are on the examples you posted? I don't. And I don't care to waste my time looking. You wanna believe what you believe...or know what you know, then hey pal kudos and more power to you. But my experiences and data all tell me differently. So lets move on a let it rest.
  17. And not for nothing, but we all know that different cars on different dynos on different days in different conditions will make different numbers. Heck numbers don't even prove where in the RPM range the power is made or the torque curve or how long the car will make that power. They're just numbers. And numbers vary wildly depending on many variables. So again, think what you want and I'll think what I want.
  18. So we can basically all agree then. Positive Displacement blower rule and Centrifugals drool. :nice:
  19. Haha! Sure man! Centri-futile blowers don't blow, they suck, lol!!
  20. Peak HP between the PD blower and the Centri is always going to be within just a few percentage points of one another with the PD blower having a MASSIVE advantage in low end TQ. There's a reason why PD blower guys almost always dominate on the street, not that we condone that type of behavior of course. We can argue until the cows come home, but when you research the dyno graphs they heavily favor the PD blowers, it's just a matter of fact not opinion. You must look at things objectively, and by sticking the 2 different blowers on a vehicle that is setup the same way (gearing, trans, tires etc) the PD blower will usually come out on top. Everyone has their own personal preferences. But, facts and dyno graphs cannot be ignored, they never lie or present a biased opinion. The 2V Modular motor loves a good PD blower based on it's inherited weaknesses from the factory.