big difference in 1 5/8 and 1 3/4 headers?
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From: Springfield,Virginia,US
big difference in 1 5/8 and 1 3/4 headers?
Hey guys, I currently have hedman long tubes on my car, but was thinking about changing to hooker long tubes. just because they are a little bigger. but is 1 5/8 really that more restrictive than 1 3/4. the hedmans fit great. and I really dont see spending that much more for something that might not help that much. What do you guys think?
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From: Denver, CO
Car: cleanest '86 sport coupe around!!
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what kinda cam are you using? the 1 5/8 will probably offer a little extra torque though.
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As long as your header ports line up with the exhaust ports on your heads, with no overlap, with long tubes you are fine.
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Im in the same boat as you are camarokid01 I have the 1 5/8's longs on my 383 I was messing around with the desktop dyno and it appeared to me that the 1 3/4 made the power curve smoother but that could just be the computer messing with me since sometimes it's accurate and other times it is not. I also noticed around a 4-5 hp increase. Anyone else have similar results?
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From: Jacksonville, NC
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Re: big difference in 1 5/8 and 1 3/4 headers?
Im in the same boat as you are camarokid01 I have the 1 5/8's longs on my 383 I was messing around with the desktop dyno and it appeared to me that the 1 3/4 made the power curve smoother but that could just be the computer messing with me since sometimes it's accurate and other times it is not. I also noticed around a 4-5 hp increase. Anyone else have similar results?
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Re: big difference in 1 5/8 and 1 3/4 headers?
As a general rule 1 5/8" headers are good up to around 400hp. Above that you definitely want 1 3/4" headers.
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