headers vs manifolds on a 318 2bbl difference ????

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318willrun

318willrun

Utube channel 318willrun
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Will headers make a difference on a stock 318 2bbl in place of stock exhaust manifolds with dual exhaust??? I say in the video that I used 2 1/4" pipe, but it was 2.5". Here are real world results !!!
 
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Are you from Canada, eh? You end every statement like a question. lol

Anyway, 2.5 tenths is worth headers. Period. Nice video!
 
RustyRatRod said:
Are you from Canada, eh? You end every statement like a question. lol

Anyway, 2.5 tenths is worth headers. Period. Nice video!
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Very close ..... In fact, my Dad 7 miles from the Canada border !!!
 
Another take would be ... "power/torque added" would be more of a difference on the ET slip in a lighter/more aerodynamic vehicle .. like a A-body
 
I can't think of a single instance where I installed headers, and the owner didn't come back after a test drive, with a big **** faced grin.
 
Following as I plan on replacing my 72ish crappy exhaust manifolds this Winter on my stockish 340 with TTI’s.
 
Nice job.
I know this goes against many of the talking heads advice on the interwebs but it has been my experience as well, Even the much maligned shorty headers have been an improvement.
 
318willrun said:
Another take would be ... "power/torque added" would be more of a difference on the ET slip in a lighter/more aerodynamic vehicle .. like a A-body
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I actually think the van is a better example because of that. I'd like to have seen comparable weather conditions. Maybe 3.5 tenths?
 
HankRearden said:
Nice job.
I know this goes against many of the talking heads advice on the interwebs but it has been my experience as well, Even the much maligned shorty headers have been an improvement.
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I absolutely agree! ......and you cannot pound that into some people's heads. Any time you change to exhaust that's one separate tube per port, and pulling the collector farther away from the ports than manifolds, you're gonna see an improvement.
 
I have a friend who had a 72 Duster Twister in 1978. 318 2bbl, 3 speed stick. All he did to that car was a set of headers, duals of course & a H.V. oil pump & that thing was awesome! I will never forget how good that car ran.
 
I had a bone stock 318 2 barrel in a 70 Challenger. Went from not turning a tire with manifolds to a one-wheel peel as long as you kept your foot down with headers. That was enough evidence for me. That said, I still have crappy manifolds on my Duster because I'm cheap and got tired of worrying about the headers hitting on previous cars. I've been thinking more and more recently about taking the plunge again.
 
1973dust said:
I had a bone stock 318 2 barrel in a 70 Challenger. Went from not turning a tire with manifolds to a one-wheel peel as long as you kept your foot down with headers. That was enough evidence for me. That said, I still have crappy manifolds on my Duster because I'm cheap and got tired of worrying about the headers hitting on previous cars. I've been thinking more and more recently about taking the plunge again.
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They say the exhaust manifolds from a 5.2/5.9 Magnum engine flow much better than the old school ones, you just have to make some head pipe adjustments.
 
niceolddart said:
They say the exhaust manifolds from a 5.2/5.9 Magnum engine flow much better than the old school ones, you just have to make some head pipe adjustments.
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Still not as good as headers.
 
I've seen a few videos where headers on an early 340 only gave small gains in hp.
Just proves hp dyno numbers don't mean much compared to actual performance.
 
ir3333 said:
I've seen a few videos where headers on an early 340 only gave small gains in hp.
Just proves hp dyno numbers don't mean much compared to actual performance.
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It don't prove anything against dyno's, just that adding 10-15+hp across the powerband makes a difference, especially at lower rpms cause it's hard to make gains there. eg.. at 2626 rpm every 5 hp gain there takes a gain of 10 tq to make it. I just think were spoiled with the amount of power we know that's available to us that's just a click and credit card away.
 
niceolddart said:
They say the exhaust manifolds from a 5.2/5.9 Magnum engine flow much better than the old school ones, you just have to make some head pipe adjustments.
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I wouldn't go to the trouble of the swap, if I already had a decent exhaust, but if installing a new exhaust wouldn't hurt digging up a pair.
 
ir3333 said:
I've seen a few videos where headers on an early 340 only gave small gains in hp.
Just proves hp dyno numbers don't mean much compared to actual performance.
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Problem with the dyno tests are they all seem to start at 3000rpm at wide open throttle. They don't show anything about driveability, part throttle, or low rpms.
 
As far as what these headers provided on this particular vehicle for bottom end torque, the 60 ft time was the same. It also felt the same off the line. The van has the factory super-tight torque converter in it, plus it's not as light as a Duster. But I can actually FEEL by the seat of the pants as the RPM's build that it is faster with the headers.
 
318willrun said:
As far as what these headers provided on this particular vehicle for bottom end torque, the 60 ft time was the same. It also felt the same off the line. The van has the factory super-tight torque converter in it, plus it's not as light as a Duster. But I can actually FEEL by the seat of the pants as the RPM's build that it is faster with the headers.
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I put a set of Try Y's on my 73 Challenger back in the day. I didn't re-jet the carb like I should have but it didn't go any faster in the 1/8th than with manifolds and stock exhaust. It was a pretty consistent 9.75's though. I can't remember the specs but I bet they were small tubes and collector. They were Mickey Thompsons. I have never seen a set since.
 
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below 3000 is where everybody drives 99 % of time. 1200 rpm to 5200 rpm is plenty on the street
and usually provides better lo rpm torque instead of high rpm hp.
 
mgoblue9798 said:
Problem with the dyno tests are they all seem to start at 3000rpm at wide open throttle.
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Mainly because it has little importance to a fully throttle run, how long are you really gonna spend under 3000 rpms even with a factory stall and gears.
mgoblue9798 said:
They don't show anything about driveability, part throttle, or low rpms.
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I wish there's was more info available on this aspect of various mods.
 
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