HOW MUCH POWER ARE LONG-TUBE HEADERS REALLY WQRTH? JUNKYARD 6.0L LS HEADER TEST!

[Music] hey guys richard holder here and welcome to the channel today we're talking about long tube headers and here's the question are they really better than stock exhaust manifolds and what about on a supercharged combination does it make sense to step up to even bigger long tube headers on a blower motor in this video we have three very cool tests the first one is comparing stock exhaust manifolds to long tube headers on a stock cam ls the next test is stock exhaust manifolds versus long tube headers on a cammed ls that's right does the camshaft change anything in our comparison between stock manifolds and the long tube headers the final test is comparing two different size headers on a supercharged ls let's get going for this video i figured the best way to illustrate the effects and the gains offered by long tube headers was to demonstrate it on a number of different combinations that way you can get a better idea on how they might work for your particular combination but this particular one was a 6 liter ly6 which is originally a junkyard motor it was ended up being the same motor that we ran on the big bang that we made over 1500 horsepower with with a turbo or with twin turbos but before we did that i actually ran this test and did a comparison i wanted to find out how well the these were the earlier the previous generation um stage one two three truck cams offered by brian thule racing but while i was doing this because when we had run the tests before we would run the the cam test with just headers and so everyone said well yeah but how well do they work with stock exhaust manifolds you don't get any gains with stock exhaust manifolds and as we know when you change cam shafts that's kind of silly because you're definitely going to get gains but what i'm going to show you here is we're going to take a look at the gains offered by the headers and i'm going to show you what happens when on this particular ly6 the gains offered on the stock cam and then the gains offered on the stage three cam so you can get an idea whether or not the gains increase as we increase the power output of the motor that you're testing it on so this was our ly6 we can take a look we ran it with a holley hp management system we had removed the vvt cam that came with the yellow wi-6 and replaced it with a stock 6 liter cam i can't remember whether it was an lq4 or an lq-9 cam i want to say that it was an lq-9 but it was a factory six liter camshaft so very mild we ran it with the stock exhaust manifolds feeding two and a half inch pipes you know exiting out so that we were simulating a type of exhaust obviously albeit a fairly open one we just didn't want the exhaust system to also be restricting it and limit the power of the exhaust systems when we compared it to the headers we ran it with stock injectors the hp management system as i said we ran it with a stock ly6 truck intake manifold which basically is the same it's a truck version of it of a factory ls3 because the ly6 is equipped with rec port heads now before you get all excited and think that the gains would be different on a cathedral port head they won't the only thing that will happen is the power output would be lower if you ran cathedral port heads on this motor and i know that because we did that test as well so the gains that you get are going to kind of be dependent on the power output of the combination that you're testing it on so you get the gains are less let's say for instance on a 4.8 liter than they than they would be on a six liter so we ran this motor first with stock exhaust manifolds feeding our open pipe we had as always a missouri electric water pump and no accessories on here and so this thing made pretty good power despite having a very very mild camshaft in it run with the stock exhaust manifolds our six liter produced 433 horsepower and 454 foot pounds of torque you can see very torquey good good six liter combination and here's what happens after we put the long tube headers on the stock cam and you can see it did indeed pick up power our peak numbers jumped up to 443 horsepower peak torque was up to 467 foot-pounds and as you can see it gained power throughout the whole rpm range from top to bottom something we come to expect with long tube headers but now let's take a look and see what happened when we ran it with this combination where we had already installed a camshaft final header test was run on a much wilder combination in this case it was still a rec port headed ls3 based motor but it actually was a b15 crate motor from the guys at gm performance the one that's designed to accept basically boost and that's exactly what we ran out we actually ran a four liter whipple twin screw supercharger and we put a uh we did a valve spring upgrade because the factory heads come with factory style ls3 valve spring so we put valve springs in it we put a healthy camshaft in it we put the comp 469 cam in at 54-469-11 which is a 617 624 lift split a 231 247 degree duration split 113 degree lobe separation angle again not specifically a blower cam but it works very well on this boosted application so we're going to show you what happens when we compare a set of inch and three quarter long tube headers to a set of larger engine 7 8 long tube headers on this pretty healthy supercharged application the supercharger was run with a 4.75 inch blower pulley and an 8 inch crank pulley and i'll go ahead and put the peak boost numbers up here so you can see how much boost we ran on both combinations the first set of headers was a set from qtp and again inch and three quarter headers with um collector extensions and no mufflers so run in this manner with the inch and three quarter headers our supercharged uh b15 crate motor produced 758 horsepower peak torque checked in at 679 foot pounds of torque you can see from a boosted application i mean the torque was basically over 650 foot-pounds through the whole range from down at 3 200 rpm all the way out to nearly 6 000 rpm and this thing was still climbing pretty rapidly and it would eventually keep going um all the way to 7000 rpm here's what happened when we added our inch and 7 8 long tube headers these were from the guys at hooker same exhaust extension three inch or three inch diameter but it was 18 to 20 inches of collector extension behind the long tube header and all we did was uh install the headers and then we had to um adjust the air fuel slightly because it leaned it out just a little bit so we wanted to have the air fuel exactly the same between the two which both of them were around 11 7 or so and you can see that the inch and 7 8 headers allowed the thing to make more power and had we continued to rev this which we did later on in this test but not with both headers unfortunately but if we kept revving it the gains you would get even greater gains from the bigger header in this application but run with the inch and 7 8 headers the combination made 774 horsepower so a good jump not much of a gain down low but we started seeing power gains once we passed the 4000 rpm range and and and even more power in the 4 500 to 5000 rpm range and as i said if we keep revving it out to 7000 the gains would get even greater with the bigger long tube headers let's get to our conclusion after running our tests with the stock camshaft on our 6 liter we also ran the comparison between the stock exhaust manifolds and long tube headers after we installed actually every one of the brian thule racing stage 1 stage 2 and stage 3 truck cams we're going to take a look at what happened when we installed the biggest of the three cams the stage 3 truck ram so run with these stage 3 truck cam and the stock exhaust manifolds on our ly6 combination produced 491 horsepower 469 foot-pounds of torque you can see you know again six liter good torque it has a stage three truck cam in it it's making pretty good power making up near 500 horsepower which is good especially for such a mild camshaft and we'll go ahead and put the specs up here on the stage 3 truck cam but here's what happened when we installed the same long tube headers on our combination compared to the stock exhaust manifolds but this time with the stage 3 truck cam you can see the long tube headers improved power quite a bit our peak power was over 500 horsepower now 504 horsepower peak torque was all the way up to 484 foot-pounds and you can notice that with the cam there seem to be even greater gains in the 3000 to 3500 rpm range here at 3200 the torque jumped up from 375 or 376 foot-pounds up to 407 foot-pounds so that's a pretty big jump in torque and that's the scavenging effect offered by the long tube headers so a lot of guys tend to think oh the headers just flow better and that's not the case actually a lot of times even shorty headers but stock exhaust manifolds because they're a lot shorter they flow actually very well sometimes more than a set of long tube headers will flow but what we're getting is a scavenging effect that helps actually draw the exhaust out and the induction air into the combustion chamber and we see that here because where it's not a flow problem down at 3000 or 3500 rpm that's actually showing the scavenging effect we got big torque gains there offered by the headers and even more so with the camshaft once we had the cam in both combinations we got bigger gains with the headers with that camshaft than we got when we had just a stock cam in here so now let's take a look at long tube headers tested on a supercharged application okay guys what do we learned from this little adventure comparing long tube headers to stock exhaust manifolds and different size headers on our supercharged combination first of all long tube headers obviously they do work they provide a scavenging effect it helps draw the exhaust out it helps draw the fresh air in the induction side and we end up making more power the cool thing is and what i want people to understand is long tube headers just don't work because they flow better they work because of the scavenging effect and we saw that it was much more pronounced once we installed the brian thule racing stage 3 truck cam and compared the stock exhaust manifold to the long tube headers on that application we saw a much bigger gain down low which again has nothing to do with flow it has everything to do with the scavenging effect the interesting thing is that we saw a greater gain as basically we went up in power and also the camshaft has an effect on that because these these pressure waves this scavenging effect is also determined by cam timing when the exhaust valve opens when the intake valve opens on the induction side so there's lots of cool things going on there on the long tube header test where we compared that on our supercharged combination i honestly think that that probably had more to do with like total flow of the bigger exhaust because we were running a motor that was making you know 750 horsepower so bigger headers were better i'm richard older make sure to like share subscribe ring the bell do all that stuff i'll keep testing

Channel: Richard Holdener

Views: 64,353

Rating: 4.9572191 out of 5

Keywords: HOW MUCH POWER ARE LONG TUBE HEADERS WORTH?, DO HEADERS ADD POWER?, STOCK LS EXHAUST MANIFOLDS, SUPERCHARGED LS, B15 CRATE MOTOR, 6.0L POWER MODS, LONG TUBE HEADERS, LOW-BUCK LS MODS

Id: 5HL_VSFDEVg

Length: 11min 52sec (712 seconds)

Published: Tue Sep 21 2021