Which Supercharger?

Built plenty of modular motors (most 4V) with centri's for street driven cars. I wasn't their biggest fan at first, but with a 4.10 gear you really will not notice any "lack" of power down low. Hits hard around 3000 and, frankly, helps keep the tires planted.

Only true problem with that is that you'll need to run a 28" tire to get down the 1/4 at a 500-600 rwhp level. But that's not too big of an issue.

Plenty of folks (myself especially included) have debated in numerous threads about gears with blowers, and it's still my opinion that for a mostly street/occasional track car, anything over 3.73s is overkill. A bolt-on 2-valve car with a 5-speed has a hard time with traction in 1st with the stock gears. A supercharged car making 600 to the tires with 4.10s? I'm sure you're not going to notice any lack of power; it's gonna roast them through 1st, 2nd, and 3rd. My car is a 400 rwhp, a 2.84 1st gear (auto), and 3.73s; I was driving last night in some cool dry air (55-60) for the first time in months, and it was chattering the tires in 2nd gear. 1st was a joke on any occasion, even rolling into it easy. Why someone would run more gear, on a 5-speed car with more 1st gear, and way more power eludes me. And as I've mentioned in other threads, spinning tires is lots of fun until you get smoked at a stoplight by a minivan (almost had this happen to me one time...almost :D)

Kenne Bell spouts that steeper gears simply aren't needed with a PD blower, and while they way over-exaggerate things, there is some truth to it. The new 2013 GT500 for example, it makes 400 ft-lbs of torque....at 1000 rpm, 500 ft-lbs at 2000 rpm, and 600 ft-lbs at 3000 rpm. That's crazy, right? That is where the fun of a PD blower is, especially the TVS blowers (a twin screw won't make that kind of torque that low in the rpm). The GT500 has 3.31 gears; you're talking about 4.10s. That's a roughly 25% increase in gear. So to make a different car with 4.10s pull the same, it needs 320 ft-lbs of torque at 1000 rpm, 400 ft-lbs at 2000 rpm, and 480 ft-lbs at 3000 rpm to make it pull the same amount (and that's ignoring the fact that the pull will be shorter due to the shorter gears). Not saying it isn't possible, but I've never seen a 600 horsepower centri car come anywhere near those numbers; I doubt 800 horsepower centri cars make those numbers.

I know what you're going to say: oh, but the low RPM torque doesn't matter that much in a race. And yes, that is 100% correct. Without really good tires and suspension, both cars will blow the tires off through 1st, 2nd, and 3rd. BUT, the real fun in that much torque, the real reason why so many people like it, is in 4th, 5th, and 6th gears. When you're in overdrive on a back country road, come up on a slower car, and can easily pull around them while still in overdrive, that's fun. When you do an on-ramp pull in 4th or 5th gear from just over idle, and you're still going in 'getting-arrested' speed territory when you make it to the highway, that's fun. When you can pull through the gears never getting about 2000 rpm, and still be running 100 mph in a matter of a few seconds, that's fun.

Well now, this post turned out about 3 paragraphs longer than planned. I'm not trying to argue, or say anyone is wrong, or anything else. Just my opinion.
 
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I cut my teeth in the car hobby with Olds and Pontiac. I like low end torque. Had a few expenses crop up, so budget is down to around $7000 for SC, AC comp, gauges. I know I can piece together a torque tech set up, but I'm to old and far to lazy for that. I like the idea of most everything you need coming in one or two boxes. May end up settling for the KB 2.1. Can't get to 550 with it, but I'll live. Not sure when I'll have money for a short block anyway. Staying with the stock gears for now. Doing a TKO 600 swap at the sametime. Already have all that stuff. I have a new set of 3.73's collecting dust in my garage if I decided I want more gear.

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Only true problem with that is that you'll need to run a 28" tire to get down the 1/4 at a 500-600 rwhp level. But that's not too big of an issue.

Plenty of folks (myself especially included) have debated in numerous threads about gears with blowers, and it's still my opinion that for a mostly street/occasional track car, anything over 3.73s is overkill. A bolt-on 2-valve car with a 5-speed has a hard time with traction in 1st with the stock gears. A supercharged car making 600 to the tires with 4.10s? I'm sure you're not going to notice any lack of power; it's gonna roast them through 1st, 2nd, and 3rd. My car is a 400 rwhp, a 2.84 1st gear (auto), and 3.73s; I was driving last night in some cool dry air (55-60) for the first time in months, and it was chattering the tires in 2nd gear. 1st was a joke on any occasion, even rolling into it easy. Why someone would run more gear, on a 5-speed car with more 1st gear, and way more power eludes me. And as I've mentioned in other threads, spinning tires is lots of fun until you get smoked at a stoplight by a minivan (almost had this happen to me one time...almost :D)

Kenne Bell spouts that steeper gears simply aren't needed with a PD blower, and while they way over-exaggerate things, there is some truth to it. The new 2013 GT500 for example, it makes 400 ft-lbs of torque....at 1000 rpm, 500 ft-lbs at 2000 rpm, and 600 ft-lbs at 3000 rpm. That's crazy, right? That is where the fun of a PD blower is, especially the TVS blowers (a twin screw won't make that kind of torque that low in the rpm). The GT500 has 3.31 gears; you're talking about 4.10s. That's a roughly 25% increase in gear. So to make a different car with 4.10s pull the same, it needs 320 ft-lbs of torque at 1000 rpm, 400 ft-lbs at 2000 rpm, and 480 ft-lbs at 3000 rpm to make it pull the same amount (and that's ignoring the fact that the pull will be shorter due to the shorter gears). Not saying it isn't possible, but I've never seen a 600 horsepower centri car come anywhere near those numbers; I doubt 800 horsepower centri cars make those numbers.

I know what you're going to say: oh, but the low RPM torque doesn't matter that much in a race. And yes, that is 100% correct. Without really good tires and suspension, both cars will blow the tires off through 1st, 2nd, and 3rd. BUT, the real fun in that much torque, the real reason why so many people like it, is in 4th, 5th, and 6th gears. When you're in overdrive on a back country road, come up on a slower car, and can easily pull around them while still in overdrive, that's fun. When you do an on-ramp pull in 4th or 5th gear from just over idle, and you're still going in 'getting-arrested' speed territory when you make it to the highway, that's fun. When you can pull through the gears never getting about 2000 rpm, and still be running 100 mph in a matter of a few seconds, that's fun.

Well now, this post turned out about 3 paragraphs longer than planned. I'm not trying to argue, or say anyone is wrong, or anything else. Just my opinion.

A few quick thoughts came to mind from your post.

1. I wasn't talking about KBs or other PD blowers - I was talking about centris, ProChargers in particular.
2. Anyone with a Fox or later Mustang chassis running a stock style suspension is a smart man to go from a shorter gear (such as 3.73 and 26") and tire to a more aggressive gear and taller tire (4.10/4.30/4.56/4.88 and 28"). Not only does the 28" have the added side effect of requiring a 15" purpose drag wheel, dropping overall rotating weight and concentrating what weight remains at the center of the hub (reducing force required to turn and parts breakage), but the added sidewall of the 28" really helps the launch, especially on a hard-hitting stick car.
3. My stock geared B headed Cobra made zilch for torque down low and first and second gear were always useless on the street. Streets are not prepped and I have never been a light-to-light guy - I've never seen a car making anywhere near respectable power do well in the first two gear simply because of the lack of preparation on the street. A 4.10/28 car is doing a 40 punch in the middle of 3rd right where a centri starts making steam and is a hell of a lot of fun. It also has plenty of what you described as passing power on the highway.

This is a car I did for a customer, one of the first ProCharger cars I did. Stock displacement built motor, stock B heads and cams (Comp Cam gears, degreed). D1 maxxed out at 15psi. I wasn't a big centri fan, still am not sure. But my God this car was fun on the street. 4.10s/28. The limiting factor was always the street. Sometimes it would hold a good pull in second fine, other times it would blow the tires off through the end of third.


Here's a relatively new, straight, clean street, a rarety here. I'm doing all I can to steer the car in the top of 2nd.
http://s688.photobucket.com/user/cjr2003firefly2/media/Mike 96 Cobra/Mike New/GOPR0915.mp4.html
 
I have had 4.10s and 3.73s with my current setup and if I could do it over, I would have left the 4.10s in, upgraded the rear suspension and bought drag radials. The 4.10s with 435 rwtq got pretty stupid, I was doing 1st thru 4th burnouts on street tires. Also, stabbing the throttle to pass in 4th when it was damp was a bad idea. However, the 3.73s aren't much better. I just put drag radials on for the 1st time and wish I still had the 4.10s, with the way it hooks now, 4.10s would cause my eyeballs to leave dents in the headrest. Just sayin...
 
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On another note: regardless of gearing, your going to see a huge difference when u slap a blower on. Take it with a grain of salt... Get the bigger blower. The 2.1 has its limitations. Cash was an issue when I got the 2.1 kit... I wish that I would have gotten the kb 2.6 or tork tech kit. Even with the bap I was at 100% duty on the fuel pump and close with the 36lb injectors.

If u do go with the 2.1, at least talk to kb and get 60lb injectors, the 40amp bap, and get an aviator pump. When I put the cams in my car, I put an svt focus pump in it due to the fuel pump duty cycle, and I still ran out of injector at 5900 rpm. From what I gather, these cams are good until around 6300 rpm, unfortunately, I cant get there with my current set up. So, take it from me... do it right the first time, so that you aren't kicking yourself in the *** later. Also, regardless of what kenne bell says, the stock MAF doesnt work with the 2.1 kit. I had to get a MAFia to correct the voltage, but again, I wish I would have just ponied up the $ to get either a lightening MAF or an SCT BA3000. Also, if you plan on running a fuel pressure gauge, your going to need to get a fuel rail adapter.

**also, make sure you let KB know that your military affiliated. they gave me a 10% discount for being active duty and did not include the chip (hence did not charge me for it) since I had to get a dyno tune.
 
A few quick thoughts came to mind from your post.

1. I wasn't talking about KBs or other PD blowers - I was talking about centris, ProChargers in particular.
2. Anyone with a Fox or later Mustang chassis running a stock style suspension is a smart man to go from a shorter gear (such as 3.73 and 26") and tire to a more aggressive gear and taller tire (4.10/4.30/4.56/4.88 and 28"). Not only does the 28" have the added side effect of requiring a 15" purpose drag wheel, dropping overall rotating weight and concentrating what weight remains at the center of the hub (reducing force required to turn and parts breakage), but the added sidewall of the 28" really helps the launch, especially on a hard-hitting stick car.
3. My stock geared B headed Cobra made zilch for torque down low and first and second gear were always useless on the street. Streets are not prepped and I have never been a light-to-light guy - I've never seen a car making anywhere near respectable power do well in the first two gear simply because of the lack of preparation on the street. A 4.10/28 car is doing a 40 punch in the middle of 3rd right where a centri starts making steam and is a hell of a lot of fun. It also has plenty of what you described as passing power on the highway.

This is a car I did for a customer, one of the first ProCharger cars I did. Stock displacement built motor, stock B heads and cams (Comp Cam gears, degreed). D1 maxxed out at 15psi. I wasn't a big centri fan, still am not sure. But my God this car was fun on the street. 4.10s/28. The limiting factor was always the street. Sometimes it would hold a good pull in second fine, other times it would blow the tires off through the end of third.


Here's a relatively new, straight, clean street, a rarety here. I'm doing all I can to steer the car in the top of 2nd.
http://s688.photobucket.com/user/cjr2003firefly2/media/Mike 96 Cobra/Mike New/GOPR0915.mp4.html

All true and valid. I was only pointing out some reasons why the OP might find a PD blower with shorter gears more idealistic than a centri-blower with steeper gears. Nothing more, nothing less.

I cut my teeth in the car hobby with Olds and Pontiac. I like low end torque. Had a few expenses crop up, so budget is down to around $7000 for SC, AC comp, gauges. I know I can piece together a torque tech set up, but I'm to old and far to lazy for that. I like the idea of most everything you need coming in one or two boxes. May end up settling for the KB 2.1. Can't get to 550 with it, but I'll live. Not sure when I'll have money for a short block anyway. Staying with the stock gears for now. Doing a TKO 600 swap at the sametime. Already have all that stuff. I have a new set of 3.73's collecting dust in my garage if I decided I want more gear.

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If you want the absolute most low-end torque, that's why I mentioned the TVS setup earlier. The max output difference between a TVS and a twinscrew will be minimal, but in the really low RPM range (<2500 rpm), the TVS will make more torque. Torque Tech makes a complete, bolt-on kit including one of these blowers at about the same price as a Kenne Bell kit. It won't quite clear a stock GT hood, but pretty much any aftermarket hood will, or if you have a hood with a scoop, you can remove the scoop, cut a small relief notch in the hood, and replace the scoop, still looking exactly factory.

I still don't know for sure if you'd want the 1.9 or the 2.3, but I KNOW the 2.3 will make a lot of power if everything else is right, too (800+ rhwp). I'm not sure what the 1.9 would do on a stock top-end 2-valve 4.6, although I bet if you spun it hard enough, it'd get pretty close to what you want. Also, that brings up a point. Don't let the displacement size fool ya. Just because the TVS is 'smaller' than the KB, it doesn't mean it moves less air. The displacement is per revolution (or cycle, or whatever it is), but the TVS are spun a lot harder and faster than twin screws, so the airflow can also be a lot more.

Also, you can build a bottom end for a probably a lot cheaper than you think. Find a set of matching, used 03/04 Cobra rods and pistons, swap them in, new bearings, new bolts, etc. and you can have a bottom end easily good to 600 rwhp for cheap, especially if you can do the work yourself. Looking back on it, I wish I would have done that when I had my motor out a couple years ago.

I have had 4.10s and 3.73s with my current setup and if I could do it over, I would have left the 4.10s in, upgraded the rear suspension and bought drag radials. The 4.10s with 435 rwtq got pretty stupid, I was doing 1st thru 4th burnouts on street tires. Also, stabbing the throttle to pass in 4th when it was damp was a bad idea. However, the 3.73s aren't much better. I just put drag radials on for the 1st time and wish I still had the 4.10s, with the way it hooks now, 4.10s would cause my eyeballs to leave dents in the headrest. Just sayin...

If it was a toy that didn't get driven a whole lot, I'd completely agree on the drag radials. But if someone was driving their Mustang the number of miles I used to DD mine (20,000+ miles a year), drag radials would get pretty expensive after awhile.....haha.
 
Take it with a grain of salt... Get the bigger blower. The 2.1 has its limitations.

.
Only if your limitations are running sub 9.8 sec in the 1/4 mile. We went 9.87 in the 1/4 with a 2.1L Kenne Bell in a 3400 car with a 26x8.5 tire. So don't sell the 2.1L blowers ability short. This blower can put out near 20 psi on a 331 cid small block. So the limitations of the 2.1 are more with the person putting the car together than the supercharger itself.
 
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Only if your limitations are running sub 9.8 sec in the 1/4 mile. We went 9.87 in the 1/4 with a 2.1L Kenne Bell in a 3400 car with a 26x8.5 tire. So don't sell the 2.1L blowers ability short. This blower can put out near 20 psi on a 331 cid small block. So the limitations of the 2.1 are more with the person putting the car together than the supercharger itself.

did you do this with the stock 2.1 inlet or a custom sheet metal piece. how did the iat's look? what pulley combo were you using?
 
Only if your limitations are running sub 9.8 sec in the 1/4 mile. We went 9.87 in the 1/4 with a 2.1L Kenne Bell in a 3400 car with a 26x8.5 tire. So don't sell the 2.1L blowers ability short. This blower can put out near 20 psi on a 331 cid small block. So the limitations of the 2.1 are more with the person putting the car together than the supercharger itself.
That’s kind of an unfair statement, when you consider how far removed the Kenne Bell kit on your buddies car is from what was sent to you in the box the day you bot it. A more fair statement would be it isn’t the limitation of the person putting the car together, but he limitation of the kit the blower is supplied with. Remember, we're talking the modular kit here, not the OHV.

As far as the 2.1L kit for the modular go, around 500whp seems to be the magic figure when it comes to spinning this blower within its maximum efficiency range and even then, that's with a tank full of race gas and ACT’s as high as 220-degree’s by the end of a run in most cases. These compressors don't seem to like to be spun really hard on the more restrictive top end of a 281ci mod motor. Most guys I've seen are lucky to break 450whp on pump gas....and that's with a host of other bolt ons. I don’t think I’ve ever seen anyone surpass 20psi on a 2.1L Modular kit the way you guys are with your OHV kit. They just don’t have the capability with that compressor with what Kenne Bell has given owners to work with.

If I recall, the kit you guys are running is fairly heavily modified with a custom intake, A/W intercooler, loads of timing sucking back a steady diet of C16….amongst other things. Not exactly the route your average owner is willing to take when it’s far easier to upgrade to the larger compressor . Not to mention feeding a heavily breathed on 331ci engine to produce far more power at lower temperatures than your average stock or bolt on SOHC 28 is.
So, for the intents and purposes of this conversation (and most realistic expectations) I’ll have to agree with usaf_branham. Power with the 2.1L compressor is going to be limited with this kit, so if power ranges beyond 400whp are the goal on pump gas, in a daily driver with go with the 2.6L, or Tork Tech 2300 TVS blower.

...and even then 550-600whp is going to be a stretch through stock 2V heads.

did you do this with the stock 2.1 inlet or a custom sheet metal piece. how did the iat's look? what pulley combo were you using?
There's nothing stock about his inlet. 95% of it is custom.

dscn1701-jpg.68540


dscn1747-jpg.68541

I'd like to know that too. Stroked Windsor, or modular? I ask due to the different inlets and manifolds and such.
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It's a stroked Windsor, not a modular.
 
Some valid points to be sure, but that is like saying if you want 400 HP don't use a 302 because as it came from the factory, it just won't get there. You have to opt for the bigger 351W or larger to get the 400 HP because it came from the factory better equipped and can be done without the level of mods a 302 would take. My point was and is: it is not the supercharger that is the problem. God forbid anyone think outside the box.
I have a N/A 325WHP 4.6 that a 2.1 Kenne Bell would easily take to 450 plus WHP without trying hard on pump gas. Would a 2.8LC do it easier? Yup, but it can also be done with the smaller 2.1.......even without heavy modification like on the race car.....by the way the race car made over 700 WHP with the 2.1. with the 2.8 LC it is making closer to 925 WHP and there is still some room for improvement.
 
My point was and is: it is not the supercharger that is the problem. God forbid anyone think outside the box.

I don't disagree with that statement. My only gripe was you seeing this as a user problem, when it in fact it isn't. You guys didn't just think outside the box....you guys tore it down to the ground and rebuilt it completely. I'm going to say that 99% of the people buying these kits aren't lacking the imagination, but frankly aren't going to have the means, or the funds to get that extensively into their build up.

Heck, I myself took a 3rd GEN Eaton M90 into 1.7L twin screw territory with the "outside the box" thinking I performed on my last car....but its not something I would recommend to your average user.

My point is that the limitations that are holding these builds back aren't the blowers, or the builders, but the materials Kenne Bell themselves have given their users to work with. Small intercoolers, limited intake and inlet volume, etc. Combine that with the small cubes and limited head design of the 4.6L SOHC and you see that only so much can be done with what you have to work with. So when you consider how much has to be changed to achieve big power levels on these modular, going with the bigger compressor isn't only the easiest route, it's by far the cheapest and most practical. If anyone was suffering from short sightedness in this venture, I have to say it was the designers at Kenne bell for leaving so much on the table when constructing the rest of these kits.
 
Just ordered the KB 2.6
That's a really nice fox for sure, but I'm not looking to reengineer/refab KB's intake system just to prove you can. Don't have the time, tools, or know how. Or the money to have someone else do it.

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I had the choice between any blower. When it comes down to it, they all cost exactly the same within $100 or so.

I picked the Kenne Bell 2.1 Innercooled Kit. It was either the KB kit or the Procharger kit.

I picked the Kenne Bell for many reasons. Power delivery, reliability, ease of installation, good looks. I am very satisfied and would not look back. I looked into the Tork Tech kit, but you need to buy WAY to much extra stuff and it takes a while to assemble. The kenne bell kit came with everything. They even forgot to charge me for my Upgraded MAF, KB CAI, and Accufab 75mm TB. They built my kit in 3 days. It was ready exactly when they said it would be. I paid Full price with kenne bell, no discount. Paid cash when i picked the blower from the KB Headquarters in CA.

I was very happy with the install Took me 2 days. Started on friday night and it was dyno tuned by Monday morning.
 
That 2.6 is a tuner kit, but you don't have to buy much for it. Belt, pulley, injectors, pump, BAP, tune. I have to get my AC compressor replaced before I do this. Running a short belt and bypassing at the moment. Pretty excited about this. I was all excited and doing hand springs around the house after I ordered it. My mom texted me 10 minutes later to tell me one of my aunts passed away this morning. Shortest hot rod parts euphoria ever.

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The 2.6 does not fit under a stock hood.... So you gotta buy a whole new hood and have it painted. Thats gonna be over $500 right there.

This is why i got the 2.1. Fits under the stock hood.
 
One of the mags did a 2.6 or 8 and pulled the scoop off and cut a relief hole in the hood. Bolt scoop back on, no problem. Scoops got to be good for something besides collecting water when I wash it. That was the big drawback to me for the TT kit. Someone here mentioned the same hood cutting trick with TT. And if it doesn't cover it, looks I'll be be a goofy bastard with cut hood driving around. Cervini's termi hood is on the list, just not quite yet.

Second page
http://www.mustang50magazine.com/te...on_ford_motorsport_power_packages_part_three/
 
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Just ordered the KB 2.6
That's a really nice fox for sure, but I'm not looking to reengineer/refab KB's intake system just to prove you can. Don't have the time, tools, or know how. Or the money to have someone else do it.

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Congrats. Just wait until the boxes arrive, it's definitely a good feeling. What route do u plan on going with the fuel pump, injectors, maf, etc?