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Finally the 4200 is getting big time boost in visibility. HRGTV Tony is using a 04 block and a 06 head - adding a turbo More to follow.
51 GMC 4.2 turbo Can't solved today's problems using the same technology/thinking that created them
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Hi efi-diy . . .
This build on HRGTV looks like fun. Can you elaborate on the thinking/benefits behind fitting an elaborate equal length header in front of a turbo?
I don't get it. It looks killer. But it seems counter-productive to delivering hot-high-velocity exhaust gases as quickly as possible to the turbo vanes.
regards, stock49
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I'm in the dark as to details.
51 GMC 4.2 turbo Can't solved today's problems using the same technology/thinking that created them
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I dig it. Cool factor A++ with extra credit. I'm curious to what it's going in. Hopefully, it doesn't die on the dyno.
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November 18th... motor trend on demand
51 GMC 4.2 turbo Can't solved today's problems using the same technology/thinking that created them
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Can you elaborate on the thinking/benefits behind fitting an elaborate equal length header in front of a turbo?
I don't get it. It looks killer. But it seems counter-productive to delivering hot-high-velocity exhaust gases as quickly as possible to the turbo vanes. In my experience with turbo cars. Having an equal length exhaust header will have far smoother turbo response, as you're not "impact"-ing the turbo so much, you're giving it more even exhaust pulses. It still has the same exhaust scavenging effect equal length headers on an NA car, however less so. If you have the room for it, equal length turbo manifold is the way to go pretty much every time
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Considering the fabrication cost ($2,000 is a low estimate), the BTU loss to underhood air (5-10 X the exposed surface area), the 3-5 year life expectancy due to corrosion and vibration fracture (compared to 20 years for cast iron) IMHO it's only valuable for competition. My engine bay temp with coated manifold and shrouded turbo is still too high. I've read comments that individual pulses have a stronger effect than the single output of an iron manifold, but that they should be significantly different lengths to avoid arriving at the same time.
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They won't arrive at the same time if they're the same length, cylinders don't all fire together.
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cylinders don't all fire together
Good thing you pointed that out, only studying engines for 55 years, that never occurred to me.
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Good thing you pointed that out, only studying engines for 55 years, that never occurred to me. glad I could help
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You really didn't understand what I wrote, did you?
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Do we need a sarcasm tag?
Also, to what part are you asking? The smug "55 years" comment or the "but that they should be significantly different lengths to avoid arriving at the same time" part?
If each cylinder has the same length exhaust then they will, by definition, arrive at the turbo at different times. They will never arrive at the same time.
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So, the answer is "yes, you didn't understand what I wrote". If not for your dismissive response I'd explain. Anyone curious can PM me.
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Dismissive response, smugness, arrogance, lack of understanding at least they didn't all drive at the same time.
"I wonder if God created man because he was disappointed in the monkey?" Mark Twain
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So, the answer is "yes, you didn't understand what I wrote". If not for your dismissive response I'd explain. Anyone curious can PM me. Let's just move on, not get caught up in anything. It's just that last part that I don't agree with. Fab cost, heat loss, everything else, I'm on the same page as you. I don't get what you mean by "significantly different lengths to avoid arriving at the same time"
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