dual wastgates?
Re: dual wastgates?
As many of you are aware, the 944 Turbo has a single port wastegate with electronic boost control. Many of you are also aware that the Wastegate on the 944 Turbo gets weak with time and there are rebuild options that can cost about GBP 700.00. However, even a new or rebuilt factory KKK wastegate for the 944 Turbo has a major weakness - it is overcome by exhaust pressure at high RPM. This means that it is very difficult to achieve more than 0.7 bar of boost at high RPM. With the standard wastegate, there is no problem reaching an increased (and brief) over boost condition at 3,000 to 4,000 rpm - but to achieve considerably more power is not possible (safely) using a factory wastegate. Power requires RPM. If your car is not making boost at high RPM - it's not reaching its true power potential.
Most of you will have noticed how your Boost Gauge falls back as the revs rise - the factory gauge reacts very slowly, but with an accurate boost gauge you would be surprised as to how much the boost tails off. In the majority of cases, beyond 4,500 rpm - the boost tails off on the 944 Turbo using the factory wastegate (both 220bhp and 250bhp models). Recently a test was performed on a standard 250 bhp 944 Turbo with new factory wastegate (these retail at GBP 1,350.00!). A maximum boost of 0.82 bar was achieved and the boost rolled off to 0.7 bar and decreased further beyond 6,000 rpm. This car made an indicated 242 bhp. This was with a new Porsche supplied factory wastegate.
Most of you will have noticed how your Boost Gauge falls back as the revs rise - the factory gauge reacts very slowly, but with an accurate boost gauge you would be surprised as to how much the boost tails off. In the majority of cases, beyond 4,500 rpm - the boost tails off on the 944 Turbo using the factory wastegate (both 220bhp and 250bhp models). Recently a test was performed on a standard 250 bhp 944 Turbo with new factory wastegate (these retail at GBP 1,350.00!). A maximum boost of 0.82 bar was achieved and the boost rolled off to 0.7 bar and decreased further beyond 6,000 rpm. This car made an indicated 242 bhp. This was with a new Porsche supplied factory wastegate.
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From: poopfacepartytime, ca, usa
Re: dual wastgates?
riceball777 Who tunes your car and with what software? Can you not get more than 370whp with 91?
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From: ashEVILle, NC, USSR
Re: dual wastgates?
As many of you are aware, the 944 Turbo has a single port wastegate with electronic boost control. Many of you are also aware that the Wastegate on the 944 Turbo gets weak with time and there are rebuild options that can cost about GBP 700.00. However, even a new or rebuilt factory KKK wastegate for the 944 Turbo has a major weakness - it is overcome by exhaust pressure at high RPM. This means that it is very difficult to achieve more than 0.7 bar of boost at high RPM. With the standard wastegate, there is no problem reaching an increased (and brief) over boost condition at 3,000 to 4,000 rpm - but to achieve considerably more power is not possible (safely) using a factory wastegate. Power requires RPM. If your car is not making boost at high RPM - it's not reaching its true power potential.
Most of you will have noticed how your Boost Gauge falls back as the revs rise - the factory gauge reacts very slowly, but with an accurate boost gauge you would be surprised as to how much the boost tails off. In the majority of cases, beyond 4,500 rpm - the boost tails off on the 944 Turbo using the factory wastegate (both 220bhp and 250bhp models). Recently a test was performed on a standard 250 bhp 944 Turbo with new factory wastegate (these retail at GBP 1,350.00!). A maximum boost of 0.82 bar was achieved and the boost rolled off to 0.7 bar and decreased further beyond 6,000 rpm. This car made an indicated 242 bhp. This was with a new Porsche supplied factory wastegate.
Most of you will have noticed how your Boost Gauge falls back as the revs rise - the factory gauge reacts very slowly, but with an accurate boost gauge you would be surprised as to how much the boost tails off. In the majority of cases, beyond 4,500 rpm - the boost tails off on the 944 Turbo using the factory wastegate (both 220bhp and 250bhp models). Recently a test was performed on a standard 250 bhp 944 Turbo with new factory wastegate (these retail at GBP 1,350.00!). A maximum boost of 0.82 bar was achieved and the boost rolled off to 0.7 bar and decreased further beyond 6,000 rpm. This car made an indicated 242 bhp. This was with a new Porsche supplied factory wastegate.
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From: st. louis, missouri, USA
Re: dual wastgates?
here is the manifold http://lovefab.com/html/h_excaliber.html
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From: RCautoworks, Bridgeview, Illinois
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From: poopfacepartytime, ca, usa
Re: dual wastgates?
sorry my question was sort of vague. I was wanting to get the lovefab turbo manifold for my h23 vtec and was looking at the one that has the dual wastegate setup. I'm aiming for 400-600whp with a methanol injection kit. I'm doing more research so I will know what i need to get.
here is the manifold http://lovefab.com/html/h_excaliber.html
here is the manifold http://lovefab.com/html/h_excaliber.html
A regular non-divided manifold with a GT35r is all you need for your power goal, the manifold will be cheaper, you will only need one WG instead of two and you can run a normal front mount IC. I know thats not what you asked but this is just my opinion.
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From: st. louis, missouri, USA
Re: dual wastgates?
Bro thats a froward facing manifold and per the literature on the site i believe it must be run with a water/air intercooler as a front mount will no longer fit, this all seems very excessive and expensive for just 400-600whp. Now if you were shooting for say 750-850 That manifold might start to be acceptable.
A regular non-divided manifold with a GT35r is all you need for your power goal, the manifold will be cheaper, you will only need one WG instead of two and you can run a normal front mount IC. I know thats not what you asked but this is just my opinion.
A regular non-divided manifold with a GT35r is all you need for your power goal, the manifold will be cheaper, you will only need one WG instead of two and you can run a normal front mount IC. I know thats not what you asked but this is just my opinion.
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From: poopfacepartytime, ca, usa
Re: dual wastgates?
Cast could work if you mod it to fit a larger WG but your on the right path with the tubular stuff, you just picked something way too hardcore.
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From: Role Model Crew !
Re: dual wastgates?
riceball777 Who tunes your car and with what software? Can you not get more than 370whp with 91?
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From: poopfacepartytime, ca, usa
Re: dual wastgates?
its a evo they are not very effcient at making power but they can sure take alot of it my good friend has a 3076 on his and is not over 500whp ever notice it takes them 30+psi to max a turbo out and we max it out on our cars well before that we got the motor they got the drivetrain.
Not to mention a freaking eg/ek/dc/em1 all have higher side impact crash ratings than an evo!
http://www.mitsubishisucks.com/cars/...de-impact.html
2 freakin stars!
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Re: dual wastgates?
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From: poopfacepartytime, ca, usa
Re: dual wastgates?
What are you trying to say here?
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