Variable vane turbos the future?!?
Haha oh man looks like huk'd on fonics is in my summer plans, sorry, you know how it goes at work, alt-tabbing between access and evom.......
It hasn't been very developed because it is a ***** to get right. Heat is the first hurdle.If you think about it, the inner curvature and shape of a compressor housing is quite crucial to flow (I imagine), so to find a way to have a housing that can change shapes, flow a lot of air with the vanes open, not be too big to make closing the vanes worthless and have this all work on the fly takes a fair bit of R&D I am sure, I'll go digging for the pic's of the setup on the new 997, I can best desribe it as vanes shaped like those in our rotors, which twist shut forming a circle, or open up creating a sort of sand dune tire looking shape if you can imagine that (with holes inbetween each crest to allow air to flow through).
Variable Vane 997 info
Scorke
It hasn't been very developed because it is a ***** to get right. Heat is the first hurdle.If you think about it, the inner curvature and shape of a compressor housing is quite crucial to flow (I imagine), so to find a way to have a housing that can change shapes, flow a lot of air with the vanes open, not be too big to make closing the vanes worthless and have this all work on the fly takes a fair bit of R&D I am sure, I'll go digging for the pic's of the setup on the new 997, I can best desribe it as vanes shaped like those in our rotors, which twist shut forming a circle, or open up creating a sort of sand dune tire looking shape if you can imagine that (with holes inbetween each crest to allow air to flow through).
Variable Vane 997 info
Scorke
997 TT owners are not exactly finding the change revolutionary at all. Modded 996 TT's are boosting as much and as soon as stock 997 TT's. Ive spent some time over on rennlist and 6speedonline and read up on it over a few posts.
http://www.holset.co.uk/files/2_5_1_5-VGT.php Thats a sweet little diagram of holset's attempt at VGT as they call it. Here is a decent pic of the unit in the 997 http://www.pca.org/panorama/pano_gallery.html .
Scorke
Scorke
A good example of compound turbocharging can be found on tractors. Alot of diesel tractors incorporate more than one turbo for heavy work loads. I have seen 3 turbos on the tractors used for pulling shows. Massive turbos that feed into one another. It was really impressive. Talk about spool up! Sounds like a damn jet! thousands....thousands of horsepower!
http://www.6speedonline.com/forums/a...8&d=1153525994
http://www.6speedonline.com/forums/a...9&d=1153526030
Eeeep, that looks like a mess haha.
Scorke
http://www.6speedonline.com/forums/a...9&d=1153526030
Eeeep, that looks like a mess haha.
Scorke
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From: chicago
Originally Posted by KazzEvo8
Shelby/Dodge put them on their reworked, showroom-offered Shadow CSX's in 89. I've heard little-to-nothing about the technology since. I'd think if it was a silver-bullet we'd have seen it in widespread use by now ...
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Joined: Jul 2006
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From: chicago
Originally Posted by scorke
The benefit is that you can have a big turbo that you can make small by closing vanes in the compressor housing I believe. Basically they stay shut creating a smaller area for spool and low end tq then once you are further into the turbos efficiency range they open up and top end power is vastly improved.
Scorke
Scorke
This is the benefit to the consumer, while the main reason for implementing this technologiy has to to with EGR recirc circuit temperatures, and a lot of stringent emission factors. It is still prety expensive technology because it's not widespread.
Originally Posted by tweak302
This is the benefit to the consumer, while the main reason for implementing this technologiy has to to with EGR recirc circuit temperatures, and a lot of stringent emission factors. It is still prety expensive technology because it's not widespread.
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Joined: Jul 2006
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From: chicago
Originally Posted by scorke
^S2000 piece of chit engine? Are you joking? How in any way shape or form is the F20 or F22 a bad engine?
Scorke
Scorke
You turbo guys should know how important tq is. i personally don't spend 90 % of my commute in the 7-9K RPM range.
^ Yup, reading through that thread the guys doing the tuning, funnily enough named Evolution Motorsports, believes that there twin Garretts that they use on the 996 tt's spool as quick yet make 600+whp with all the supporting mods.
I must say I do respect the guys doing this work on these cars, it takes some size of a sack/cranium to pull apart a 130k dollar car and start goign to town. They also said that although they do not think these turbos will flow anywhere near the garrett's yet that they are in the beginning stages of trying to modify them, I say in a year or two, we will see these in audi's v dub's diesel trucks (I know these are going to be in the next F250 but shhhh), and so on. Once lots of tuners get there hands on them I am sure it will be exciting, from what I read on the 6 speedonline forums it seems that HEAT is the issue. On the 997 turbo there is an overboost button that you can push to run some extra boost(18psi) but only for spurts of 10 seconds or less, in fear of frying the god knows how many $$$$ per unit turbos.
Scorke
I must say I do respect the guys doing this work on these cars, it takes some size of a sack/cranium to pull apart a 130k dollar car and start goign to town. They also said that although they do not think these turbos will flow anywhere near the garrett's yet that they are in the beginning stages of trying to modify them, I say in a year or two, we will see these in audi's v dub's diesel trucks (I know these are going to be in the next F250 but shhhh), and so on. Once lots of tuners get there hands on them I am sure it will be exciting, from what I read on the 6 speedonline forums it seems that HEAT is the issue. On the 997 turbo there is an overboost button that you can push to run some extra boost(18psi) but only for spurts of 10 seconds or less, in fear of frying the god knows how many $$$$ per unit turbos.
Scorke
Originally Posted by scorke
^ Yup, reading through that thread the guys doing the tuning, funnily enough named Evolution Motorsports, believes that there twin Garretts that they use on the 996 tt's spool as quick yet make 600+whp with all the supporting mods.
I must say I do respect the guys doing this work on these cars, it takes some size of a sack/cranium to pull apart a 130k dollar car and start goign to town. They also said that although they do not think these turbos will flow anywhere near the garrett's yet that they are in the beginning stages of trying to modify them, I say in a year or two, we will see these in audi's v dub's diesel trucks (I know these are going to be in the next F250 but shhhh), and so on. Once lots of tuners get there hands on them I am sure it will be exciting, from what I read on the 6 speedonline forums it seems that HEAT is the issue. On the 997 turbo there is an overboost button that you can push to run some extra boost(18psi) but only for spurts of 10 seconds or less, in fear of frying the god knows how many $$$$ per unit turbos.
Scorke
I must say I do respect the guys doing this work on these cars, it takes some size of a sack/cranium to pull apart a 130k dollar car and start goign to town. They also said that although they do not think these turbos will flow anywhere near the garrett's yet that they are in the beginning stages of trying to modify them, I say in a year or two, we will see these in audi's v dub's diesel trucks (I know these are going to be in the next F250 but shhhh), and so on. Once lots of tuners get there hands on them I am sure it will be exciting, from what I read on the 6 speedonline forums it seems that HEAT is the issue. On the 997 turbo there is an overboost button that you can push to run some extra boost(18psi) but only for spurts of 10 seconds or less, in fear of frying the god knows how many $$$$ per unit turbos.
Scorke
I wouldn't be able to take that kind of pressure.
Originally Posted by tweak302
Are you serious, yes it has 240 HP, but come on, was the torque on backorder?
You turbo guys should know how important tq is. i personally don't spend 90 % of my commute in the 7-9K RPM range.
You turbo guys should know how important tq is. i personally don't spend 90 % of my commute in the 7-9K RPM range.
Scorke
Originally Posted by scorke
I love tq, more than HP, but I also know that your never ever going to get a "torquey" 2.0l NA motor, where as a 240 hp one is very fun to drive, although you have to wring its neck.( I am aware the new s2k has a 2.2)
Scorke
Scorke