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Well, you don't have to be an engineer to figure that out.. But knowing how pressure works on seals etc, not counting the drag on the engine with turning a lobe forced with higher backpressure etc. Read about the whipple, then about the Kenne Belles then on to the E-force, Saleen uses the simliar design as the E-Force... You will also notice that since the air is brought into the front of the supercharger into the base (underside) of the super charger you elimate about 270 deg of bends (this causes back pressure) wich means a higher boost to overcome it.. Boost is not necessarily the pressure you mashing into your engine but pressure is more related to the backpressure of the system.. A more accurate way of measuring the effect of a supercharger is not with Boost pressure, but by the actual CFM of the supercharger...

 

GNB

 

You mean the back pressure is slowing my car with the Whipple?

I'll tell you, it sure doesn't feel like it! I press the throttle, she flies! With the "perfect" canned FR tune, this little SGT is a quick, responsive beast!!! Just MHO, you can't go wrong with the Whipple SAI installed with canned tune. Look at my dyno numbers below...

I trapped 116mph after serious lagging in the 60'. I'm not sure what the potential is, but I can tell you, you won't be dissatified.

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+1 it rips....search out the posts by Dennis Whipple, there are many threads if you search, I debated forever! I am more than very happy with the Whipple, I love to hear it whine and I shoot for the boost whenever its safe...make sure you are pointed where you want to go you get there quick...perfect.

 

+ 2

 

No regrets here, love my Whipple!!!!!!!!!!!!

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I also have the Edelbrock Supercharger and couldn't be happier. I can't compare it to any of the others, but as everyone told me before I decided what to buy... it doesn't matter which brand you buy, you can't go wrong supercharging these cars. It will feel like a new car after and you will smile everytime you put your foot down. Good luck!

 

Jim

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  • 4 weeks later...

I went with the Saleen Series VI because I could keep my FRP intake and I liked the front intake vs. the whipple/roush/kb side intake setups. just a personal preference. I also like the fact that the service interval on the Saleen setup it 50,000 between oil changes. A local speed shop had seen issues with KB units leaking after 5-6k.

 

The decision was tough because I really wanted to send the car in to have SAI put the Whipple kit on it, but that would have been another $2k compared to my setup.

 

I've been very happy with my setup so far. Great power, easy to swap pulleys and I have multiple tunes for different ocatne fuels.

 

They all make great power so it really is a personal decision. Have fun with it and good luck.

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I went with the Saleen Series VI because I could keep my FRP intake and I liked the front intake vs. the whipple/roush/kb side intake setups. just a personal preference. I also like the fact that the service interval on the Saleen setup it 50,000 between oil changes. A local speed shop had seen issues with KB units leaking after 5-6k.

 

The decision was tough because I really wanted to send the car in to have SAI put the Whipple kit on it, but that would have been another $2k compared to my setup.

 

I've been very happy with my setup so far. Great power, easy to swap pulleys and I have multiple tunes for different ocatne fuels.

 

They all make great power so it really is a personal decision. Have fun with it and good luck.

 

 

The Saleen isn't really a front intake S/C... the only one that has a true front intake is the Edlebrock.. As far as all the posts saying the Mustang does not live at 2000RPM's, well, lets just say they are in some fairy tale.. Sure, if your at a race track you are always in the higher RPM's, but if your a daily driver look at your TACH.. Yup, 2000RPM's

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Well, in my "fairy tale", if you are cruising at 2,000 rpms, you aren't looking for boost or more power, used as a daily driver, you don't want or need more HP/TQ that low, it would just be a waste of fuel. My comment was made to point out that the 4.6l doesn't "live" or "come to life" and start making real power till 3K plus rpms, it wasn't a reference about where the tach is during a commute to work...

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For all you guys that are confused, and there are alot of them,.,..

 

How many of you guys have a RACE only Shelby?, If you do, and don't use it as a driver then you have a car that "Lives in the higher RPM range"

The real deal is our cars "LIVE" in the 2000 RPM range, that is a fact and the reality of what your driving. To say your car doesn't is a first stage of denial. I do not know anyone who drives down the freeway in their Mustang in third gear at 70mph just to ensure they are ready for the next race...

 

Once you accept where your car is driven most of the time is when you can build your engine to perform appropriately.

example, whould be a daily driver like a 70 camaro onthe street with a tunnel ram and two 850 cfm holleys on top, I mean really?? then the guy wonders why he is always getting beat in the quarter when he should be running the salt flats!

 

With new turbo technologies out there the turbos are really coming along, but at our RPM's, the S/C is the best option. If you have a street driver, why would you install cam's that do not come on until you hit the 5000RPM's I would be looking at a cam that comes on from the 4000-6000 that is a realistic range.

 

Another thing I see alot here is, guys talking how they have a S/C in the 550hp or better on a stock motor, how they run all this boost,,,,then later you read how they broke things.. If your going to run a S/C on a stock motor, I would realistically run under 500hp and be safe doing it. If you want big boost pressures (I cannot understand why) then beef up your rotating assy. If you know anything about building motors, you don't need high boost pressures to put out large HP numbers.

 

As Chester Bushy would say "Real men do not need NOX to make HP, they build the motor!" I think the same applies with boost...

 

GNB

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I'm still confused I guess, are you saying that because i'm cruising down the highway in 5th, running 2k rpms or whatever, that I need boost and power at 2K? WHY wouldn't i just shift to 3rd when I want the power? I really don't get the comparison to a tunnel ram when, from what i understand, boost DOES come on between 3-4K rpms with centri's and turbo's, what's the similarity? Nobody launches at 2K rpms, and my confusion is really preventing me from seeing why you need or want more power that low in the band...

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Well,

 

I guess you never will get it then.. just keep sending your motors out to get done, never lift a wrench or truly understand the whole ideas behind an engine build.. Me I will keep building my own stuff, alwasy have and always will and I have never had a mechanical failure.. Some guys beleive performance comes from whatever an engine builder can do, others beleive its all about the exhaust or the ammount of chrome installed.. Can any of you guys really degree a cam/s? I can,, to beleive that you can buy a set and just install them is another fairy tale...

 

My point is this.. Our cars do in fact live around 2k,,, and I mean where do you normally drive? sure you can down shift, how far down do you want to go? go too far and the revs are to high, not high enough and your outside your engines peak horsepower curves. So all these guys that just bolt stuff on, or depend on another machine shop to do the work don't really have a clue, a real performance minded person will build their engines around where the car "Lives" for us daily drivers it truly is between 2000-4000rpms for peak power.. The idea behind the curb is to be in the curve when HP and torque are increasing and neither is falling off... When either curve falls off then your out of your peak range, this usually happens after the 4000 rpm range somewhere depending on alot of factors cams etc.. All internal parts have to work together in harmony...

example: I had some joker telling me the "Hot rod" cams were great to use with a Supercharger, when in fact they were detrimental to the S/C.. A S/C needs about a 115 degree valve seperation, other wise your wasting the boost... Study Study... You either know what your doing or hope your mechanic does..

 

BTW, if turbos were so great off the line, they would have put them on the Budwieser King or Gene Snow's rail when he broke the 5 second barrier...

 

GNB

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Take all the opinions these forums have to offer, read and research, visit shows, races etc and talk to those that have them, and then decide what is right for you for what you want out of it, not what someone thinks is right. I went with the Whipple 550 but that's what I wanted. I like the clean install, the look, the reliability and proven performance so I got it. Not one issue since install over a year ago. I don't bash centrifugal units or turbos's, to each his or her own.

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It still sounds as if you are saying that we should all beleive that we NEED full hp/tq at 2k rpms, and apparently its so tricky to downshift a car, that you would just leave it in whatever gear you are in and push the pedal halfway to keep it in the 2-4k range magical-fairy-tale power band that's the best thing since sliced bread and your set up will just magically throw you back in the seat? It took me a whole 5 minutes to figure out that if i'm below 50-55mph, I go to 2nd, above that I take 3rd, for the daily driving you are talking about, there's not really any other issue to be concerned with about downshifting.

 

If my car "lives" at 2k rpms, explain to me how when i'm getting on it (which is the time that I want the extra power), my rpm's don't get any lower than 3,500-4,000 between the shifts? The car is built to stay in the power band just as it sits, I really don't understand what I'd gain by having more low end power, even with 275's or 295's most guys are spinning on launch still with FI of any kind, right?

 

You can try and insult me/us about our lack of engine knowlege since you can degree a cam all you want, I've done everything to a vehicle you can think of outside of rebuilding the rotating assembly and rebuilding a transmission.... gears, axles, clutches, heads, intakes, water pumps, racing suspension, air ride suspension, bare frame restorations, custom paint work, custom body modifications, the whole ball of wax.... I just don't care much for oil and grease, and while I COULD do it, I'd rather have a guy that does it all the time build it so that when I push the gas, I'm not second guessing what I did or didn't do "right" the once every couple years that I would actually put a engine together if doing it myself...

 

and on the turbo comment off the line, you are comparing a street car to a 5 second drag rail? really? How about comparing a turbo'd and a screw s/c'd car of the same make/model that have the same peak hp ratings and same gearing and tires? THAT would be meaninful info that I'd love to see! 0-60 times on the same tires would be great too!

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It still sounds as if you are saying that we should all beleive that we NEED full hp/tq at 2k rpms, and apparently its so tricky to downshift a car, that you would just leave it in whatever gear you are in and push the pedal halfway to keep it in the 2-4k range magical-fairy-tale power band that's the best thing since sliced bread and your set up will just magically throw you back in the seat? It took me a whole 5 minutes to figure out that if i'm below 50-55mph, I go to 2nd, above that I take 3rd, for the daily driving you are talking about, there's not really any other issue to be concerned with about downshifting.

 

If my car "lives" at 2k rpms, explain to me how when i'm getting on it (which is the time that I want the extra power), my rpm's don't get any lower than 3,500-4,000 between the shifts? The car is built to stay in the power band just as it sits, I really don't understand what I'd gain by having more low end power, even with 275's or 295's most guys are spinning on launch still with FI of any kind, right?

 

You can try and insult me/us about our lack of engine knowlege since you can degree a cam all you want, I've done everything to a vehicle you can think of outside of rebuilding the rotating assembly and rebuilding a transmission.... gears, axles, clutches, heads, intakes, water pumps, racing suspension, air ride suspension, bare frame restorations, custom paint work, custom body modifications, the whole ball of wax.... I just don't care much for oil and grease, and while I COULD do it, I'd rather have a guy that does it all the time build it so that when I push the gas, I'm not second guessing what I did or didn't do "right" the once every couple years that I would actually put a engine together if doing it myself...

 

and on the turbo comment off the line, you are comparing a street car to a 5 second drag rail? really? How about comparing a turbo'd and a screw s/c'd car of the same make/model that have the same peak hp ratings and same gearing and tires? THAT would be meaninful info that I'd love to see! 0-60 times on the same tires would be great too!

 

Thank you,,, You made my point,,,, Some people will never understand..

As far as insulting goes, I was not insulting, thank you for yours.

I do know alot about building engines, High performance and street engines as well, I have done plenty, since you have not I guess it would be safe to say that you do not. Yes, a 5 second rail is a good point. I could also have used High performance Diesel's to support my comment on turbo's, yes I have built those too.

The Rpm's, I am sure you always leave a light at 3,500-4000rpm's and replace your tires every week, I tend to try and leave a light or tree around 2000rpm's. Sure, I am sure everyone out there goes down the street honks three times at 45 miles per hour and commences their little street drag at 4000+ rpm's, all the while endangering others out there who are not "dragging"

I think the only person I can think of out there off the top of my head who's vehicle "lives" in the higher RPM's is Kahmann (forgive spelling) and this is because he roads races (sanctioned)

 

Yeah, sure its easy to know where the gas goes, and not putting it where you pour in the oil is a plus but if you don't know WTF your talking about when it comes to engines, forced induction etc, other than what you have read, until you have built them then your just another armchair quarterback.

 

GNB

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LOL, sorry if i'm coming of as hostile OR insulting!

 

I really just want a clear answer as to why it's so important for the power to be down low, of course i don't hit every stoplight as if it's a race, that's the whole point here, i don't NEED more power when daily driving!

 

You seem to be telling me over and over that the power band should be 2-4k, but I still don't understand WHY you would want or need it there!!!

 

I've given my rationale for WHY I don't think I need more power in that range, and you're response about leaving a light at 2k really is what I'm agreeing with here, IF I wanted or needed more power to leave a light, I would be hitting 4k, dumping the clutch and going full throttle, so by putting more power at 2k, it SEEMS as if the result would be simply leaving the light at 1k-1500k instead.... do you follow my reasoning? I just cannot think of a situation where I would want more power but NOT want to hit higher rpm's to get to it, it just seems counterintuitive to me.

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LOL, sorry if i'm coming of as hostile OR insulting!

 

I really just want a clear answer as to why it's so important for the power to be down low, of course i don't hit every stoplight as if it's a race, that's the whole point here, i don't NEED more power when daily driving!

 

You seem to be telling me over and over that the power band should be 2-4k, but I still don't understand WHY you would want or need it there!!!

 

I've given my rationale for WHY I don't think I need more power in that range, and you're response about leaving a light at 2k really is what I'm agreeing with here, IF I wanted or needed more power to leave a light, I would be hitting 4k, dumping the clutch and going full throttle, so by putting more power at 2k, it SEEMS as if the result would be simply leaving the light at 1k-1500k instead.... do you follow my reasoning? I just cannot think of a situation where I would want more power but NOT want to hit higher rpm's to get to it, it just seems counterintuitive to me.

 

Jmn444

(how did you come up with this username? curious)

 

The reason I state the 2000-4000 Rpm's is that for us street guys it is where the best "usable" horse power is.. Sure our blocks can go to 6-6.5k but the best range for HP, efficiency etc is in this range.. Then its all about the gears tranny etc. After those RPM's the torque and HP falls off.

for example, if your in 2nd gear, wind the motor to say 5800 where your numbers are falling, then grab 3rd, you may find that as soon as your in third your RPMs may be either to high in your curves, when if you had shifted sooner you would be in a lower RPM range and in the peak values..

Alot of racers will have shift lights (hate em) set at different values for different gears (ralley drivers do this )

I hope this clears up what I was saying, did not mean to bash or be hostile either, just trying to explain where I am coming from.

 

GNB

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my initials, then kept adding 4's till it wasn't used by another user, goes back to another website a long time ago, tooooo lazy to come up with something new :)

 

Now, the only part of what you are saying, that I still don't get or agree with, is that the power curve is more usable 2-4k, I get/understand the curve, but if you use a turbo or centi, isn't the curve simply moved up the rpm scale to where you wouldn't "fall off" too much before hitting redline anyway? Are you really shifting at 4K to stay in that power band?

 

I think the centri maybe shows this better than the others, but on these charts, it's clear the turbo, even when it's falling off the curve, is still above the peak hp of the KB twin screw at similar boost levels... SO, if i'm shifting at 4k anyway when i want to go fast, why is this not the better option?

 

Dyno graphs to compare

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my initials, then kept adding 4's till it wasn't used by another user, goes back to another website a long time ago, tooooo lazy to come up with something new :)

 

Now, the only part of what you are saying, that I still don't get or agree with, is that the power curve is more usable 2-4k, I get/understand the curve, but if you use a turbo or centi, isn't the curve simply moved up the rpm scale to where you wouldn't "fall off" too much before hitting redline anyway? Are you really shifting at 4K to stay in that power band?

 

I think the centri maybe shows this better than the others, but on these charts, it's clear the turbo, even when it's falling off the curve, is still above the peak hp of the KB twin screw at similar boost levels... SO, if i'm shifting at 4k anyway when i want to go fast, why is this not the better option?

 

Dyno graphs to compare

 

That is a good read... Thnx..

 

GNB

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that's why I went from this,

IMG_3780-2.jpg

to this,

Picture045.jpg

 

 

Andrew,

 

Did you install the Tec S/C yourself and if so was it a clean instaa (good directions and come with a good tune)

 

How much RWHP are you getting with this setup,

 

Thanks,

-Billy

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Andrew,

 

Did you install the Tec S/C yourself and if so was it a clean instaa (good directions and come with a good tune)

 

How much RWHP are you getting with this setup,

 

Thanks,

-Billy

 

It's not Andrew's SGT. Had the install done at Tasca along with the stroker motor. The base Techco kit was very complete and offered good directions. But as you can tell we did a few upgrades (TB and Maf). So far we have gotten 641rwhp.

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It's not Andrew's SGT. Had the install done at Tasca along with the stroker motor. The base Techco kit was very complete and offered good directions. But as you can tell we did a few upgrades (TB and Maf). So far we have gotten 641rwhp.

 

+1 ....Billy, when I replied to GT500-07's post and photos I let it post his photo's again ..still a great looking engine !

 

Take Care

Andrew

 

PS here is mine

 

web.jpg

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I recall seeing several engines in Hot Rod magazine years ago that had both superchargers and turbos...the supercharger was supposedly to improve power in the lower rpm until the turbos spooled up and took over boost duties at higher rpm. I don't follow the hobby or racing that much anymore...wonder if anyone still tries a double setup?

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I recall seeing several engines in Hot Rod magazine years ago that had both superchargers and turbos...the supercharger was supposedly to improve power in the lower rpm until the turbos spooled up and took over boost duties at higher rpm. I don't follow the hobby or racing that much anymore...wonder if anyone still tries a double setup?

 

they are called compound boost systems. Hellion makes a kit for the GT500 and 03-04 Cobra

http://www.hellionpowersystems.com/index.p...icle&id=140

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