Got a great deal on an IW 10 percent lower pulley. Hoe much boost do you gain and whats the total boost on a 13 after installation. It will also be added with all other supporting mods, intake, tb, xpipe. Thanks guys! Anybody have a 10 percent over a 15. Is their any advantage? Anybody do the lower with an upper or is that a bad idea or maybe overkill for the blower?
how much boost does the 10% lower pulley create?
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Huh....10%
just kidding, on my 07 it made about 3-4psi
just kidding, on my 07 it made about 3-4psi
I agree, if your going through the trouble to change it, why not do the 15?
Bc 400 bucks is 400 bucks haha im hoping its just worth 15 hp... but i could be wrong. I figure itll spin the blower and accessories a bit less as well. Which maybe safer lol im just trying to justify my decision of getting the 10 lol
Definitely worth 15HP.
It will spin the blower faster but has no affect on the accessorie drive belt. But if you are going to do a upper also you will pick up 2-3 more psi then just the lower.
The more important question is how fast will you be spinning the blower and will it be past it's efficiency window? Boost is a measure of pressure build up (resistance) and can vary depending what mods have been done (like LT headers, porting etc)
(I posted this a while back)
The TVS's best RPM efficiency range is at about 18,000 rpm's....as it spins faster it starts to loose some efficiency. Anything above 20,000 is definitely past the blower's efficiency where heat soak will also become a major factor.
To put this in perspective @ 7,000 engine rpm's:
(1) stock 2.7 pulley will turn the blower .......@ 18,726 rpm's
(2) 10% OD lower pulley will turn the blower @ 20,664 rpm's
(3) 2.4 Upper pulley will turn the blower .......@ 21,145 rpm's
(4) 15% OD lower pulley will turn the blower @ 21,697 rpm's
All things considered, over all I would agree with going with the 10% lower vs any smaller upper or even the 15% lower.
how about posting figures of what the SC will spin at when the engine is spinning at 6K or 5K rpms....not many guys here are going to take these cars to a 7k rpm redline, myself included. Hell most of the time im shifting around 6 if Im hitting it hard, less most of the time
Been reading up on industrial Air compressors.
Either the automotive guys have been copying the industrial designs or vise versa?
In general the consensus is that the conventional Roots blower has seen its day.
The Twin Vortices (TVS) or the rotary lobe compressor as referred to in the industrial world, are modified Roots based PD Blowers that are about 10% more efficient than a straight Roots lobe blower matching or even slightly bettering a screw blowers efficiency up to about 18-20 Psig of boost. I was always a fan of the KB/Whipple but there is a reason OEM’s now use the Eaton TVS. At 24 Psig, the screw blower is still ahead of the TVS, but that’s race gas/ built engine.
I suspect there would be a real market for 2.8-3.0 L TVS blower for these motors including the 5.4, & 5.8 Ford ,along with the LS1 & LS6 guys. With Lower IAT’s at around 18-19 Psig, I bet there is another 50 HP to be had on 93 Octane and the stock bottom end making the TVS the best street blower.
Turbos beat PD or screw blowers for max eff. & power period , but I like my boost instant & down low. Turbos are another animal in terms of complexity tuning & plumbing.
Either the automotive guys have been copying the industrial designs or vise versa?
In general the consensus is that the conventional Roots blower has seen its day.
The Twin Vortices (TVS) or the rotary lobe compressor as referred to in the industrial world, are modified Roots based PD Blowers that are about 10% more efficient than a straight Roots lobe blower matching or even slightly bettering a screw blowers efficiency up to about 18-20 Psig of boost. I was always a fan of the KB/Whipple but there is a reason OEM’s now use the Eaton TVS. At 24 Psig, the screw blower is still ahead of the TVS, but that’s race gas/ built engine.
I suspect there would be a real market for 2.8-3.0 L TVS blower for these motors including the 5.4, & 5.8 Ford ,along with the LS1 & LS6 guys. With Lower IAT’s at around 18-19 Psig, I bet there is another 50 HP to be had on 93 Octane and the stock bottom end making the TVS the best street blower.
Turbos beat PD or screw blowers for max eff. & power period , but I like my boost instant & down low. Turbos are another animal in terms of complexity tuning & plumbing.
I used the 7000rpm limit because that is where the 2013 engine red line is set. When sizing a blower pulley you should always base it on engine RPM limiter (red line).
There are other factors to consider about not exceeding manufacture's compressor maps. Anything above those limits will not only take the blower out of it's efficiency range but can even put the blower integrity in jeopardy.(bearings etc)
If you are exceeding those limits efficiency drops exponentially and all you are doing then is building heat.
Here is the compressor map of the 2.3TVS. You can clearly see anything above 20psi or 20,000 rpm's will take the blower efficiency completely off the map and out of range.
There are a lot of salesmen out there who will sell you anything just because it is the the newest item out there they can make money on. It doesn't mean it's the right thing for your car.
Understood, however the 7K rpm redline is not the true redline to me, since its a over-rev feature that can be held for 7 seconds. The actual redline is 6250 rpm....so I was just asking for the sake of argument :shrug:
FYI
10% lower @ 6250 would be @ 17,873 blower rpm
15% lower @ 6250 would be @ 18,565 blower rpm
Edit: 7 seconds at 7000 rpm is more than enough time to create heat-soak and pull timing with a 15% lower.
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thank you. Is that just the lower or adding the smaller upper pulley?
Just the lower added to the stock set up.
One thing to keep in mind is the intercooler and heat exchanger are very efficient and at the speed you will be traveling at in 2-4 gear your are not going to get heat soak and keep in mind that most people are driving the car in the 2-5k range and that's where the real gains from the extra boost shows itself . But yea if you are looking at if from a pure all out performance point then yes if you plan to drive the car in the 6500-7000 rpm range all the time then get a bigger blower. In a 10-11 second pass at the track you will be 6500-7000 rpm range for what maybe 1.5 seconds in first and 2-2.5 seconds in second and will not get there in third, I will also say my inlet temps are lower at the end of the track then they are leaving the line.
That compressor map sure tells a lot
Thank you very much for the compreesor map!
That is excellent information. I did not realize that the TVS was that small. I suspect the efficiency map is the blower efficiency less mechanical losses as the TVS seem very good, i.e almost 20% better than most Roots.
Look at the sweet spot around the BEP and you see the TVS is an excellent blower up to about 12-15 Psig and 14,000 RPM. The efficiency map lines also cover a large area, meaning that the blower works nicely over a wide range of speed and pressure ratio. The 2.3 TVS is a good blower for a street Termi, not the GT 500.
For a TVS sized to match the pump gas potential of the 5.8, 3.3 L is more appropriate.
I can only imagine what the design and tooling cost would be for a larger TVS rotor scroll! As a larger TVS would not have the OEM volume, cost would probably match at TS. As the 5.8L stock makes 600 RWHP on a good day, I suspect there will be no call for a larger TVS from the OEM group.
It would be interesting to see the compressor maps from Whipple and KB and the Lysholm 3300 http://www.lysholm.us/gt500.php
Note that HP gain comes from both Lower IAT and less power required to drive a larger blower. A larger blower could consume 40 HP less at 6500 RPM. Lower IAT, Maybe 30 HP? This will get interesting with the 5.8 having Ford GT cam profiles. I realize that another 75 peak HP will not change 1/4 mile times by that much, but it will make a heck of a dyno graph.
I used the 7000rpm limit because that is where the 2013 engine red line is set. When sizing a blower pulley you should always base it on engine RPM limiter (red line).
There are other factors to consider about not exceeding manufacture's compressor maps. Anything above those limits will not only take the blower out of it's efficiency range but can even put the blower integrity in jeopardy.(bearings etc)
If you are exceeding those limits efficiency drops exponentially and all you are doing then is building heat.
Here is the compressor map of the 2.3TVS. You can clearly see anything above 20psi or 20,000 rpm's will take the blower efficiency completely off the map and out of range.
There are a lot of salesmen out there who will sell you anything just because it is the the newest item out there they can make money on. It doesn't mean it's the right thing for your car.
Thank you very much for the compreesor map!
That is excellent information. I did not realize that the TVS was that small. I suspect the efficiency map is the blower efficiency less mechanical losses as the TVS seem very good, i.e almost 20% better than most Roots.
Look at the sweet spot around the BEP and you see the TVS is an excellent blower up to about 12-15 Psig and 14,000 RPM. The efficiency map lines also cover a large area, meaning that the blower works nicely over a wide range of speed and pressure ratio. The 2.3 TVS is a good blower for a street Termi, not the GT 500.
For a TVS sized to match the pump gas potential of the 5.8, 3.3 L is more appropriate.
I can only imagine what the design and tooling cost would be for a larger TVS rotor scroll! As a larger TVS would not have the OEM volume, cost would probably match at TS. As the 5.8L stock makes 600 RWHP on a good day, I suspect there will be no call for a larger TVS from the OEM group.
It would be interesting to see the compressor maps from Whipple and KB and the Lysholm 3300 http://www.lysholm.us/gt500.php
Note that HP gain comes from both Lower IAT and less power required to drive a larger blower. A larger blower could consume 40 HP less at 6500 RPM. Lower IAT, Maybe 30 HP? This will get interesting with the 5.8 having Ford GT cam profiles. I realize that another 75 peak HP will not change 1/4 mile times by that much, but it will make a heck of a dyno graph.
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