Are headers a thing anymore?

[PontiacHO]

Small block Chevy V-8's sure did wake up with headers and quality exhaust, you are correct about exhaust leaks (cheap headers) and melted plug wires however.

True but how often are you really going to enjoy the top end RPM benefits (of headers) with a street driven car? Showing my age….I like the Corvette “Rams Horn” manifolds. They flow very well. I think any street car that’s required to run mufflers is restricted more by the flow of the mufflers than anything else.

 

[Skippy722]

True but how often are you really going to enjoy the top end RPM benefits (of headers) with a street driven car? Showing my age….

Headers can improve low end torque as well.

That being said… when my exhaust manifold studs inevitably break a set of catted long tubes (because I don’t want to smell the exhaust anymore than anyone else) will replace my manifolds.

 

[PontiacHO]

Since you are a Mopar man, find be a Duster, Demon, or Dart with a 340 or a 360. I love those. I recall a 1970 Duster 340, 4 speed, and 391 rear that spanked all the big block GMs except for an L88 Corvette (427). This guy could shift that Duster so well it sounded like an automatic. When you get old you harken back to the glory days…

 

[Infomercial]

I got some in the mail the other day. From what I read it is mostly for looks and sound. I should have significant weight savings after replacing the whole exhaust. I already have a cold air intake and ecu tuner.

 

[Trav]

My '68 Cortina GT came with factory headers. Not mine pictured but loved that car.
View attachment 126281

Nice! I had a 65 Lotus Cortina DOHC with 2 weber side drafts and a long tube header. The 65 had a generator and was a positive ground electrical system. I miss those old Cortina's too.

 

[RDY4WAR]

Headers aren't for just high rpm. A good set of headers, matched well to the engine, can improve power and efficiency everywhere in the curve. The tri-Y headers I put on the 289 SBF in my '66 Mustang picked up +6 lb-ft right off the hit at 2000 rpm, was +8.5 average lb-ft better from 2000-4000 rpm, and picked up +19 HP at 5200 rpm.

The restriction in something like the ramhorn manifolds isn't in the flow but the primary and collector dimensions. With such short primaries, there's no wave harmonics happening. The exhaust mass velocity plateaus quickly with no opposing pulse reflection to scavenge the cylinders. This results in more natural EGR effect with more residual exhaust gas in the cylinder, higher residual cylinder temperatures, reduced combustion efficiency, and loss of power.

For a low rpm cruise state, you want to keep up exhaust velocity far away from the exhaust valve like you do at high rpm and WOT. The lower rpm needs much longer primaries to make that happen.

Improving combustion efficiency improves everything. Fuel economy and power both increase, emissions decrease, chamber and piston deposits decrease, exhaust gas temps and head/coolant temps decrease, etc...

I had a 2007 Focus with the 2.0L Duratec. I ditched the stock log-ish manifold for a tubular manifold and GT28RS turbo with FMIC at 12 psi. It had custom cams from Crower and some head porting as well. I ran a 2.5" downpipe and intermediate pipe to a straight-thru style muffler and no cat. It PASSED the tail sniffer in Maryland. Granted the numbers were toward the higher end of the range, but it still passed. With the help of Benjamin Franklin, it passed the visual part too. lol All emissions equipment was gone and ignored by the tune. Even with the turbo, cams, and 4.06 final gear, I still averaged 1-1.5 mpg better than advertised highway mpg. I would bet it was putting out less emissions per mile driven, per minute idling, than when it was choked by its own farts from the OEM.

 

[PimTac]

The Mazda SkyActiv engines have tuned headers.

 

[OVERKILL]

Headers aren't for just high rpm. A good set of headers, matched well to the engine, can improve power and efficiency everywhere in the curve. The tri-Y headers I put on the 289 SBF in my '66 Mustang picked up +6 lb-ft right off the hit at 2000 rpm, was +8.5 average lb-ft better from 2000-4000 rpm, and picked up +19 HP at 5200 rpm.

The restriction in something like the ramhorn manifolds isn't in the flow but the primary and collector dimensions. With such short primaries, there's no wave harmonics happening. The exhaust mass velocity plateaus quickly with no opposing pulse reflection to scavenge the cylinders. This results in more natural EGR effect with more residual exhaust gas in the cylinder, higher residual cylinder temperatures, reduced combustion efficiency, and loss of power.

For a low rpm cruise state, you want to keep up exhaust velocity far away from the exhaust valve like you do at high rpm and WOT. The lower rpm needs much longer primaries to make that happen.

Improving combustion efficiency improves everything. Fuel economy and power both increase, emissions decrease, chamber and piston deposits decrease, exhaust gas temps and head/coolant temps decrease, etc...

I had a 2007 Focus with the 2.0L Duratec. I ditched the stock log-ish manifold for a tubular manifold and GT28RS turbo with FMIC at 12 psi. It had custom cams from Crower and some head porting as well. I ran a 2.5" downpipe and intermediate pipe to a straight-thru style muffler and no cat. It PASSED the tail sniffer in Maryland. Granted the numbers were toward the higher end of the range, but it still passed. With the help of Benjamin Franklin, it passed the visual part too. lol All emissions equipment was gone and ignored by the tune. Even with the turbo, cams, and 4.06 final gear, I still averaged 1-1.5 mpg better than advertised highway mpg. I would bet it was putting out less emissions per mile driven, per minute idling, than when it was choked by its own farts from the OEM.

Well stated!

Yes, a good set of headers promotes much better flow via scavenging, which is the result of the pulse-draw effect, as you've mentioned. Properly balanced, the pulses create a bit of vacuum, aiding in evacuation of the next pulse in line, improving velocity and creating a "draw" effect, which as you note, improves cylinder evacuation (reduces EGR).

I had the same experience as you, though mine was more accidental. My '87 GT T-top barely passed emissions. I wasn't rolling in money at the time I had the car and the smog pump added weight and complexity. When it seized up, I deleted it and all associated plumbing, blocking off the air injection holes in the back of the heads with plugs. The emissions place didn't know this stuff was supposed to be there, so that was good. I maintained the EGR. It wasn't until I went to do the exhaust on the car that I discovered that the PO had hollowed-out the cats. I was shocked, delighted and amused that it had passed emissions in that state. It passed yet another time as well.

 

[thastinger]

Back in the day we were into putting headers on our cars and turbo exhaust systems. Is this still a thing anymore? Can modern cars benefit from headers?

Half the engines have turbos now so they may have something that looks like a shorty but all of our "modern" engines that are NA have some version of a cast iron shorty header OEM.

 

[PontiacHO]

Headers aren't for just high rpm. A good set of headers, matched well to the engine, can improve power and efficiency everywhere in the curve. The tri-Y headers I put on the 289 SBF in my '66 Mustang picked up +6 lb-ft right off the hit at 2000 rpm, was +8.5 average lb-ft better from 2000-4000 rpm, and picked up +19 HP at 5200 rpm.

The restriction in something like the ramhorn manifolds isn't in the flow but the primary and collector dimensions. With such short primaries, there's no wave harmonics happening. The exhaust mass velocity plateaus quickly with no opposing pulse reflection to scavenge the cylinders. This results in more natural EGR effect with more residual exhaust gas in the cylinder, higher residual cylinder temperatures, reduced combustion efficiency, and loss of power.

For a low rpm cruise state, you want to keep up exhaust velocity far away from the exhaust valve like you do at high rpm and WOT. The lower rpm needs much longer primaries to make that happen.

Improving combustion efficiency improves everything. Fuel economy and power both increase, emissions decrease, chamber and piston deposits decrease, exhaust gas temps and head/coolant temps decrease, etc...

I had a 2007 Focus with the 2.0L Duratec. I ditched the stock log-ish manifold for a tubular manifold and GT28RS turbo with FMIC at 12 psi. It had custom cams from Crower and some head porting as well. I ran a 2.5" downpipe and intermediate pipe to a straight-thru style muffler and no cat. It PASSED the tail sniffer in Maryland. Granted the numbers were toward the higher end of the range, but it still passed. With the help of Benjamin Franklin, it passed the visual part too. lol All emissions equipment was gone and ignored by the tune. Even with the turbo, cams, and 4.06 final gear, I still averaged 1-1.5 mpg better than advertised highway mpg. I would bet it was putting out less emissions per mile driven, per minute idling, than when it was choked by its own farts from the OEM.

Seeking every once of power then yes go with headers but all the other aggravating issues that are created ain’t worth the less than 10 lb ft that was recognized. (Referring to street cars) IN MY OPINION.

 

[sk_pete]

A lot of modern cars have them OEM, hiding under the heat shields.

or it´s inside the head, watercooled.
and cat is right at engine.

 

[jkasch]

Nice! I had a 65 Lotus Cortina DOHC with 2 weber side drafts and a long tube header. The 65 had a generator and was a positive ground electrical system. I miss those old Cortina's too.

I was a poor college student at the time and the Lotus version would have been my dream. I did put a heavy rear anti-sway bar on it which made it steer pretty neutral and run it in some autocrosses. Really was a fun car.

 

[JTK]

A lot of modern stuff has the exhaust manifold built into the cylinder head. The exhaust exits the head through one or two collectors.

Yep, pentastar V6's are like that as is Nissans new 3.8L used in the Frontier. On both it's just one big rectangular opening in the center in the cyl head and the catalytic converter assembly bolts right to it.

 

[OVERKILL]

A lot of modern cars have them OEM, hiding under the heat shields.

The OE SRT manifolds kinda look like a less than great shorty header, lol:

On the other hand, the RAM manifolds just look like manifolds:

 

[930.engineering]

.
Two of my cars are turbo'd, one of uses this ....

... and one is NA. It looks like this:

 

[PontiacHO]

1967 L88 427 Corvette exhaust manifolds…

1968 Pontiac Ram Air 400 exhaust manifolds

1964 Ford Galaxie 427 exhaust manifolds

 

[RDY4WAR]

Let's not forget that performance isn't the only consideration with the OEMs. They also have to be sure the exhaust manifold(s)/header(s) will physically fit in the engine bay. There's also likely time factors with assembly line.

 

[Jetronic]

giukietta qv headers + turbo (welded together)

 

[PontiacHO]

Aftermarket headers enhance performance but on street cars can create issues with heat soaked starter motors, cooked power steering and trans cooler hoses/lines, almost inaccessible oil filter, and melted upper control arm bushings. Seen that happen on the last Chevelle (big block) that I owned. If (and that’s doubtful) I ever did use headers again I would wrap them with the header insulation wrap. It ain’t pretty but it’s effective.

 

[Cujet]

Since you are a Mopar man, find be a Duster, Demon, or Dart with a 340 or a 360. I love those. I recall a 1970 Duster 340, 4 speed, and 391 rear that spanked all the big block GMs except for an L88 Corvette (427). This guy could shift that Duster so well it sounded like an automatic. When you get old you harken back to the glory days…

I am old, and my memory is just fine. I clearly recall driving through rain and having the distributor short out and cylinders start misfiring, until it would quit running all together. I remember the terrible traction in the snow, the god-awful handling characteristics, cracking exhaust manifolds, the non stop rust, the sagging doors, the low quality and the promise of power that never seemed to quite live up to the promise.