Exhaust Header Bash!

BangkokDean

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Exhaust Header Bash! Testing Power Loss From Dents - Engine Masters Ep. 4

[ame]http://www.youtube.com/watch?v=azPKIjxmmdU[/ame]
 
Ok, now I won't feel so bad when I have to mangle up my Hooker headers to fit my tall deck big block into the chassis. They are stuffed in currently, but not bolted up because they don't fit. Thanks for the enlightening video. :)
 
Well, I've read one day an physic engineer saying that only the intake was crucial, being 'low pressure' it was susceptible to flow perturbations.
OTOH he was saying that since exhaust gaz were high pressure, header design wasn't making much difference, stuff get out anyway.
I was septical at the time, now I believe him.
Header are such a pain on my SBC, in term of space and heat management, I'm wondering if there's a cheap, light stock-looking manifold around.
I'm not talking about stock manifold because I'm sure those are restrictive.
 
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Also makes yow wonder about "Stepped" 4-2-1 and other header "magic." Wonder if there is similar DYNO data for those - not bashing 'em - just good comparisons.
 
When moving to Florida, I managed to find a used set of headers in great condition for my SBC this was late '97 , put them on and they fit fine, I forget the name on them....maybe Hooker, not sure, but far as I would tell they were equal length.....

Winter 01-02 I was putting in Rack steering and no matter WTF I was doing, it was impossible to get the rack into the needed position due to #1 cyl pipe, so talking it over with the guy down the road at Jr's Muffler shop, Ricky recommended Schoenfeld Headers, so I went online and looked around #151 is the choice, and the routing is significantly different, kind of close on the angle plug heads, but I use Jacobs ceramic boots and put that problem to bed, another long story over THAT little bitch :shocking: but at any rate, they clearance everything just fine, and didn't cost much......

Trick is they are NOT EQUAL LENGTH HEADER PIPES, not that I notice it anyway, my H pipe is behind the trans, being a 200 4r for the ODrive.....and 2.5" pipes into stainless Magnaflows in rear, street driven, so I dunno if anything changed, I even had it out in the RAIN yesterday...:pprrtt::gurney:
 
I'm not that impressed or worried about their findings, what made my eyes bug out was

First--Hitting a hammer with a hammer is one of the stupidest (re: dangerous) things you can do! My shop teacher would have kicked me out for that but ya know what? I tried it anyway when I was older and still have a little piece of shrapnel inside of me from it!

Second-- Taking a sledgehammer to your headers while they are still bolted on to your still hot aluminum heads???? Hot or cold, aw man, come on!

If these are the kind of machine shop practices these guys use, even if only for a you-tube video, well I ain't gonna put any faith in anything they tell me.
 
Hitting the hammer with a hammer is a myth with todays metallurgy. I think it was even on mythbusters

as for the headers, all that proves to me is the exhaust is oversized for that engine
 
Myth or no myth, out of 5 swings Estwing to Estwing, I got hit by 3 bits of shrapnel. Two of them just drew a little blood on my arms, but the third hit me in the groin, and bled enough I went to the emergency room. It was close enough to my 'sensitive parts' the doctor declined to try to remove it. It caused 'uncomfortable feelings'--no, it hurt-- for years when I engaged in certain activities in certain positions, and more recently again when I underwent an MRI.
I still have both hammers, with three chips missing from the face of one of them. That was about 1980, but that's one myth I will believe, thank you, modern metallurgy or not.

I agree with you about the pipe sizing though.
 
I agree that is a mild and modest motor and the primary tube diameter is too large. and you are loosing some combustible mix out the exhaust

anything larger than the exhaust port area would tend to reduce pressure...

though stepped headers are interesting from a tuning perspective almost like a expansion chamber on a 2 stroke...

check out the Chevy power service manual on intake runner length and diameter and its effect TQ

ah just make it 600-700 inch BBC and put some boost to it... :smash::smash::smash:
 
Hitting the hammer with a hammer is a myth with todays metallurgy. I think it was even on mythbusters

as for the headers, all that proves to me is the exhaust is oversized for that engine

Looking at those headers I don't see them being too big for that motor.
 
Myth or no myth, out of 5 swings Estwing to Estwing, I got hit by 3 bits of shrapnel. Two of them just drew a little blood on my arms, but the third hit me in the groin, and bled enough I went to the emergency room. It was close enough to my 'sensitive parts' the doctor declined to try to remove it. It caused 'uncomfortable feelings'--no, it hurt-- for years when I engaged in certain activities in certain positions, and more recently again when I underwent an MRI.
I still have both hammers, with three chips missing from the face of one of them. That was about 1980, but that's one myth I will believe, thank you, modern metallurgy or not.

I agree with you about the pipe sizing though.

That does sound painfull :twitch:
 
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