Header Theory Dyno Test 

This was Engine Masters before it was a show!!! :D

I think it would be great to see you try the same test on a stock low performance big block, with very little to no modifcations, because some of us guys can't afford to build an expensive engine, like me I just want to do simple modifications to gain a little bit of horsepower, and I would like to know what would be the better header on a stock engine

Thank you very much! Good to know. Big and Bad 427 I would clearly have thought needed 2" Headers. Had 1-7/8" on my Chevy 350 and they made a big difference.

Sat in that room with Steve before and learned the truth about what I built (I was happy) Steves a great guy and a true professional.

These guys are a world of info..Steve and the Dyno guy is awsome

That was well worth viewing, and helped me make up my mind.👍

that's amazing on the ceramic coating!

Cool men, keep up the fantastic info videos. Solid on ceramic coated headers for sure. A no brainer after watching this video.

I didn't know Robert Duvall was into Dynoing engines.

The difference in power between coated/painted headers will actually be more once the engine is installed due to the lower underhood air temps effecting intake air density. The dyno cell is less effected by this even though they could feel the difference.

i love ceramic headers...went from waiting for engine bay to cool to working on motor to leaving car running and working on motor

Great work guys! I'd be interested in what a good set of large tube Tri-Y headers would compare . . .

I want to say thanks for going to the cost, ,time and trouble so that i may learn this. I appreciate it

Dulsich...You are the man.... Great job !!

I Love this kind of video. to actually get to see the difference with headers. Awesome video!!!

What a great video with proper data.

Love your stuff guys, keep it up.

Coated vs uncoated, I wouldnt have expected a dyno difference in numbers. Theres no physical changes to increase airflow. The performance comes when smashed into an engine bay and the air temps are being sucked up by the intake. heat is being absorbed by the fuel, oil temps are skyrocketed, and cooling systems are running on full squirrel. Thats when your coated headers will really shine, especially ceramic, IMO. I am glad for the info on shorties vs long tubes,a nd the diameter numbers Thanks!

Hey John Hunkins!!! You did the photo shoot of my 3rd gen Camaro (Ennis, Texas, July 1998) for GM High Tech Performance. I was your reflector holder. ;)

on this particular comparison , it might have given some useful information as to whether a collector extension in its own right ,or in an increased diameter aided the shortie in recovering some of power difference to long tube pipes.

Thanks for the info. Even though the shorty would be an easier fit, I think I will go threw the extra work and get me a set of ceramic long tubes. By the way that is crazy about how much heat the non coated headers put out. Thanks again.

@17:50 "we'll see you on the newstand folks" says nobody ever anymore... lol.

Great test worthwhile Information

Guys, your vid took such a good theme about engine building. The problem is its impossible to understand the first part of the video because of the noise in the dyno bay. Please keep in mind to do the chatter in a silenced room.

Great video guys, good to see some back to back data.... on the ceramic coating debate "does it make more POWER", you really need to test it in an engine bay. I don't like rolling road dyno's for testing because there are too many extra variables, BUT, the extra heat inside the engine bay will have a HUGE impact on induction temperatures. That 500 degrees F that you picked up, is robbing you of extra timing you can't use, its also stopping you really getting the most out of your mixture.... but unfortunately, you won't see that in a dyno test cell where there is 1000cubic feet of ambient air around the engine v's 4 cubic feet of very hot air inside your engine bay. The air the carby is sucking in aside, there is also the soak thru the intake manifold. Great video though, I took a lot away from it as I'm sure everyone else did :)

Sometimes it comes down to what fits the chassis as well. Have 3 different headers for my '62 Impala & none fit right. Went back to Corvette ram horns because they fit. Have some awesome headers for a future project now.

very interesting vid, thumbs up guys!

WOW! An amazing heat difference. Hell, I would say for a SAFETY aspect, any spilled trans or motor oil (roll over / accident) on the coated header probably won't flash ignite, but a 800+ degree tube will FOR SURE bring oils to the flash point & ignite. Great to know...

An older video. But I'm sure the info would be the same if re-tested today. Something to think about for sure. I liked and subbed, thanks

Missed this video before - there are special dyno' test headers available, or they can be fabricated, with easily fitted insert pipe sections to change the primary lenghts, even secondaries and, for roughing out hte lengths, some are full slip overs, like a trombone slide.

Regarding the ceramic coated headers. There is also a big benefit due to not having 800 degrees radiating to your intake and raising IAT’s. 👌. I had plain stainless headers before my ceramics. Car felt like an oven on Broil after a drive. Now it’s very bearable.

Look at Dulcich all clean shaven and fancy lookin .

Great show we need the Steve and Steve show

Now this is how you prove your point! Numbers don't lie

You should have a huge stereo in the engine room , I bet blasting rock music at it adds 50 horsepower

Great work

I would like to hear the guy's talk about building a motor with a very low torque curve for Towing. Not all of us can afford a Cummins but a lot of us have an old 70's through 90's Dually laying around and the funds to make improvements.

Handheld infrared thermometers have a disadvantage when measuring an object that reflects light well. This characteristic is called emissivity, or the ability of an object to absorb or emit energy. Therefore the lower temp on the shiny header.

Good stuff. The only thing missing is a test of stock-style exhaust manifolds. Would have liked to see how much shorty headers improve over stock & also a test of 2" primary shorties or mid-lengths as well.

Love your show, still like to see a engine with a v-6 and short headers vr long tube ,i also would like to see even vr uneven headers and if your using shorty headers would like to see different sizes as well

The only problem with running headers that have larger diameter primary tubes is clearance issues especially on a street car. I’m surprised how much difference the ceramic coating makes though.

I run shorties on my car for emissions, they are coated, huge diff with under hood temps, I love 'em. But pricey

My father taught me a trick for finding collector extension tune length, (or any other exhaust stack or system) start long, spray regular non high temp paint stripe on it, run at rpm you desire to tune it to for long enough with a slight load ( driving down the road at 6k rpm in low gear say,) In a few seconds a little oval spot burns first in the paint, cut that spot in HALF! And hang on. Got me 5lb of boost on a hot M35A2 ! He said, "You will see a sharp cone of flame coming to a pencil point when you are plowing with a gas engine and tuned straight pipe!" then with the lights off at night and me hanging on the side of the tractor he'd say dial the fuel screw until it goes rich with red fire, then pull it back until the fire turns blue! Then, if you are good, you can get the purple center, and a shock ring forms around the flame directly above the pipe. There will be more rings forming inside the flame as volume increases, but the distance between them changes with frequency and DENSITY! Park a shock ring directly above a pipe at full load and hold on! Keep advancing the distributor until the flame is pink. If you can, before it rattles, then reset the carb and repeat in small increments! it will run like crap around the farm, but on a cool night like this with a little fog on the pull track at the fair tomorrow, she'll sing! Then, it is the only time you use a timing light to record what worked best in the field. Oh, and those long rams i have? You can tune an intake that way too and make em park a shock ring of intake charge and exhaust sound directly over the piston at overlap the higher the rpm the worse it is! That's how i split a bellhousing on a 727 at 7500 rpm when i hit third gear! He has passed now, ive been driving and tuning them for 30 years now and have had low compression iron head smog 400s and 440s in C bodies with that dang experimental cam blow through a 6300 rpm orange box on its way to 8300 in high fricking gear! It's really fun to get everyone in the newport calmed down, turn around, and go back and see black mark sets dissappearing away in front of you! They can't be seen from the other way, but when those tires fry and the tach jumps every 800 rpm there they are, the latter the longer! Ran on 89. Two thermoquads and 4.10s on a 440 in a newport stock 8.2 pistons and heads. Got 21mpg. Only transportation. In the winter. Pulled gravity bed wagons. Art Chizum at oceola said it was the winningest car of oceola dragway. Made a perfect run. Bolt on exhaust and street tires, remove sandwiches from under the intake and have supper, load trunk, place trophies on dash, and drive home. I was tuning and building that 6 pack and setting up gears and building automatics machining everything by 13 years old. I also did a chassis setup. It didn't ride right or sit right, but when those homemade traction bars hit those junkyard special custom cuts and lubricated spring packs and lifted the front end, she came out straight and level! With 1" of daylight under the tire! Sorry for the book. Getting older, no kids, just hoped someone would remember!

Well done!

Great info thx for making this video.

I want to test long tube Tri-Y pipes where the 2 tubes come together right above the 2 into 1 collector.The #1 and #5 cylinders are piped together and the #3 and #7piped together. With the rotation of the crank and the position of the pistons, everything should work together assisting the scavenging of adjoining holes. I have not seen this type of header and I know it will be more efficient and make more power.

Are those headers tested with the same air/fuel ratio ?

great video.

Something that would be interesting to see is a header's effect on supercharged and turbocharged engines. Conventional wisdom is they don't make much of a difference as long as they're large enough, but I've never seen anyone actually test it.

I sure do like Steve Brule. Even though he didn't talk much in this video he really knows his stuff. I would go as far as to say he is today's version of smoky yunick. I wish engine masters was still free on RU-vid.

Also keeping heat in the exhaust helps with condensation mitigation as well as extending the life of your catalytic converter. Also extends life of hoses and wiring.

Some discussion about matching the header tubes to the ports would be useful. Small tubes on big ports are not ideal obviously. How much effect does eliminating a step at the flange have? Maybe comparing small tube headers with no enlargement at the port to the same headers with tubes and flanges enlarged to match the port opening would be revealing.

I saw the episode of engine masters where they bashed headers almost closed and didn't see much in the way of performance loss. I'm betting, and this is just a theory, that the major improvement doesn't actually come from the tube diameter for more than about 2 inches from the cylinder head. I'm betting a set of headers with large tubes right at the head, dropping to smaller tubes quickly after wouldn't decrease power much if any. I want to see THAT theory tested.

I would like to know if the afr changed between the headers as well as if the intake was a limiting factor.

All those free parts mmmm nice

Good video

It would be interesting to see if the coated headers improved a turbo engines power.

My old camaro 406 cube after boring a 396 .060 over 4bolt mains early thick wall casting block ran crane compu cam f280390 cam with .663 intake .728 exhaust lift and triple springs under titanium retainers peak horses at 8700 rpm open chamber rectangle port heads fully massaged in 1976 which could be beat easily today used 21/8 inch long primaries 4inch collecters into a capital h with a balance tube and internal neck down then neck back up to 4 inch again was supposed to flow better. Made great power but there are better plugs out these days plus would use available bigger flow thru mufflers built for diesel engined big trucks like freightliner

Are shorty header is still better than a stock log style manifold, on a small block or big block

I'd like to understand how a header primary diameter that is larger than the diameter of the exhaust valve itself can produce more power. Many high-perf BBC engines (maybe this one included) had 1.88 (1-7/8") dia. exhaust valves. That given size can only move a fixed cfm (granted, varies by engine speed), but it just seems that a 1-7/8" primary size really should be all you need to not create a restriction at the exhaust port. Maybe the fact that there is a bend in the header that is close to the port exit point is helped out by increasing the diameter? Would be interesting to test straight or zoomie-type headers this same way to see how much the bend actually impedes flow with a given primary diameter...

Such a kettle of fish here, did you adjust the jetting to fine tune to each header diameter? But very thorough video, thanks

I'd be interested in the torque numbers down low. ie: 1000-3000rpm, do the shorties hurt as much or at all that low ?

I’ve been running a set of cheap summit brand headers on my big block camaro(mainly because I was doing a budget build and it was all I could afford) but with the hot humid summer days here in south Louisiana the water temp gets up to 220 when I run the air and around 210 with the air off. I just bought some ceramic headers to see if that helps. I also have a griffin dual pass radiator and 2 spal puller fans and one pusher fan on the front side of the radiator

Tests at WOT, are great. ...But.. I have BBC 502 in a 4200 lb Divco Have you ever done tube length and Dia, a real world test on, what would be a street driven motor, up thru the gears.... I have no problem leaving the red light with wheel in the air. Looking to get as much advantage as possible form the 502. I have no problems with the drive train ( 4l80e and 355 torsion diff )

Very wonderful!

Interesting comparison and evidence for people who think larger/open is always better, that torque drop with NO collector surprised me and 60 pounds is certainly a lot to lose or gain.. I am 65 and about 1975 i built a 67 RS Camaro Yenko clone with a 427/425 with 456 gears and a 4 speed and naturally i had headers then everything was uncoated but people used to paint them, Hooker VS Appliance for cost, etc. Steve with that nice 427 engine does that have the OVAL port heads or rect? Asking because there was so much controversy back in the day between the OVAL and RECT. As you probably know the rect. came on the 427 HP versions like the 425 and 435 version with the solid cam and 4 bolt main and the bigger valves. Man i would have been running low elevens easily with 600 hp and pump gas too

I would be curious on the difference in the length of the turns and the angles on the tubes coming off of ech port. I am sure there are differences with space being an issue. Those factors would help/hinder one size to the next. Also I watched a vid on here where they intentionally put dents in the headers and (not dings) and they made more hp after dented. I am sure there isn't a header company testing that because god forbid they spend some of their profit on research for performance rather than just cobble up a set of headers for $30 and sell them for near $1000

I wish they'd do a "tuned length" header and an equal length headers. "Back in the day", equal length was the bees knees.

Including the Dyno Data using Collector Extensions is very Informative but some Common 427 in size motor builds tune Best with 12" length Extensions......

does anyone know if the tuning was changed after each header change? I'm thinking of getting long tube headers, and they are always training to sale a tuner with it. Does this set up include a a/f wide band meter to tune on the fly? I can't imagine they changed the tune after every header change, so I'm wondering if shops selling tuners with headers are taking advantage...

Would there be a diferance in a shorty style header v.s an equal length shorty?

Lol, the fat guy @11:57 with the orange baseball cap and glasses could be a SNL skit character. 😆

Could you do s review on Zybar coating, they make extrodanry claim on radiant heat.

Well my question is where does that heat go or stay when it's ceramic coated? Isn't is bad it keeps all the head inside, bad for aswell the exhaust as the engine?

Wrapped headers compared to ceramic headers?

How does the surface of the material affect the reading of the infrared thermometer?

A couple of things that would have been interesting to see would have been a shorty header with a 3" collector. Also testing the shorty headers using a collector extension. Maybe even seeing a tri-y header tested. Great video though!!! Maybe do a header testing part 2?

have you tested any of the bearing & piston coatings?

I have to question the true heat results of shiny ceramic coated vs black painted. Emissivity of a IR temperature gun is typically calibrated to a surface it will be used against. Shiny light colors do not emit IR as well as a black surface that emits IR much better. In my former job doing coatings for pipeline we had 2 IR guns depending on what we were coating. A tan plastic or overlaying that with a white plastic. Lab even had their's calibrated specifically to a hot plate when checking gel time of fusion bonded epoxy. I don't doubt the ceramic kept heat in pipes but 600 degrees difference is a little extreme.

ceramic headers = under bonnet temp huge benefit for a street driven car -

I don't think the dyno can show the value of coatings. If the tubes move the same amount of air (and they should), then the only other variable would be the Temperature. The Temp would have a greater affect under a the hood of a car where they impact the intake temps than it would in an open and airy dyno room. Like to see the same type of test on a car on a dyno...

I can’t find those flat face headers on Summits site for a SBC are they not making them anymore? 67 chevy Camaro is the application.

Which ones were leaking at the head or was all that carbon from somewhere else.

How do we figure out what we have done to our engines without a dyno? I got an unknown 350 for cheap enough that I doubt it's anything performance. 041 heads from what I can tell by the front casting. Mild cam from how it idles at 600 rpm. Edelbrock 600 cfm, edelbrock performer manifold. The logs and exaust are bigger than the stock 83 k20, I think 3 inch now and has cat and muffler. I'm hoping its somewhere close to what the engine wants while keeping it quiet. It pulls a travel trailer so I manage to use it's full throttle and max torque legally. I will always wonder what the heck I actually put in my truck. All I can say is somewhere between 145 and 600 horse? Probably 300 or under is my honest guess. I ran a break in on the cam and have driven litterally across the country and back pulling a trailer, maxes out about 55 or 60 in the mountains and can do over 80 at sea level without rejetting. No trailer and I can certainly do illegal things in it. It does pre ignite with low octane so every other tank I use mid and that keeps it at bay. Every second tank itll ping again so I try not to do that. I'm guessing 10:1 c/r? It's got 2.72 gears in the axle and th400. I'm thinking about goofing with that though, 4.10s and an od trans but for the cost of that what's a few more dollars in the tank instead?

Id like to see a fenderwell type header

Weren't the 1-7/8" Shorties the lowest 2 lines? Major difference and not very good if that is the case. Or were the two lowest lines stock manifold?

Why did you lower the revs for the extension ?

How did you forget what David Vizard told you on turning the pistons around in the Pinto motor?

Hey. I would like to know the rev times comparatively. I have always been told that long tubes or low back pressure in general will assist in you RPMs climbing faster. If so it would be nice to know the difference.

What size are the exhaust ports on a the heads?

Would the same differences be with smaller cube engine?

The advantage of ceramic coated headers really comes into play inside the engine bay with the hood closed. Especially for people still running an open air filter on top of the engine. Do a couple of pulls with a car on a chassis dyno and you'll see a result.

1,7/8" ceramic coated

Hi... Actually this is the best video so far in automotive hp finding... Can i know what is the bore and stroke of the engine you testing in .. thanks for those info. Have a great day

How much Horsepower and Torque does the engine make without the header?

turned the captions on, that helps

Looks like 1 7/8 is way to go

Hi guys i've been reading a lot of comments about blanking off EGR systems could you tell me if you ever tested this system open or deleted. im sure viewers would like to know if they get their EGR deleted will the engine have better performance power and fuel economy and then if the engine is remapped to compensate for this deletion of the EGR would this make the performance even better

if your intake is sucking from under the hood you would see a difference in performance due to increase in temp.

I run Ceramac MAC headers. I noticed they don't start to perform until they have really warmed up, which usually takes a couple hours of driving, or on the hi way, that's where I notice it the most.