Dundon GT4/Spyder Race Header Group Buy
#437
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will hopefully get to go for a drive tomorrow or Thursday, i'll let ya know, double demerits will probably start Friday, this nanny state country
so pretty keen to give it a squirt before the fun police come out in force
Mechanic said the quality and fitment were excellent, O2 sensor a little tight
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Mechanic said the quality and fitment were excellent, O2 sensor a little tight
#438
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#439
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Creates a bit more of a "vacuum" by emptying the exhaust completely. Essentially goes along with their "tuned header" description.
#440
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This creates scavenging? How does it evacuate if sealed at the end? I am intrigued.
#442
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This is why we call all of our designs "tuned length", not long tube as longer isn't always better. It's the tuning that creates power throughout the entire powerband.
The 4th tube is a patent pending design that aids in a number of parameters that enhance our ability to tune the headers...
Can't say too much as not just customers watch this thread...
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Dundon Motorsports
Gig Harbor, WA
253-200-4454
jamie@dundonmotorsports.com
www.dundonmotorsports.com
Facebook.com/dundonmotorsports
Instagram @dundon_motorsports
#443
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Not so much fluid dynamics as it is pulsed gas flow. The gasses leaving a cylinder when an exhaust valve opens creates a pressure wave (imagine the picture of a bullet leaving a gun...) That pressure wave expands, reflects and is redirected back to the head. If the timing is correct you get the reflected expansion wave (now a "suction wave") back to the cylinder head when the exhaust and intake valve are both open. This allows more air to be removed from the cylinder and also pulls fresh air into the cylinder through the intake valve. Some headers get this right by accident, some of them get this right by design.
This is why we call all of our designs "tuned length", not long tube as longer isn't always better. It's the tuning that creates power throughout the entire powerband.
The 4th tube is a patent pending design that aids in a number of parameters that enhance our ability to tune the headers...
Can't say too much as not just customers watch this thread...
This is why we call all of our designs "tuned length", not long tube as longer isn't always better. It's the tuning that creates power throughout the entire powerband.
The 4th tube is a patent pending design that aids in a number of parameters that enhance our ability to tune the headers...
Can't say too much as not just customers watch this thread...
#444
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I understood that tuned headers only work over a certain RPM range (due to the fixed length of the headers combined with variable engine speeds leading to the rebound timing only "working" in certain ranges). Is this what you mean by working over the entire "powerband" - ie a certain rev range. If so, what range have you targeted?
#445
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Hey Mike, I will be there (if my schedule holds) with MVP for the 3 days. My only engine mods will be the headers/filters / and tune. Hopefully we are in the same run group. Than we can run tests the whole 3 days if we desire.......
#446
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I think where the fourth tube ties in to the collector it is sharing sonic/pressure pulses with all 3 cylinders, not just one, but that's based purely on what I can see from the few photos I've seen on this thread.
#448
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#449
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PA is so boring, wishing we were located in TX so I could get in on this haha
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