Shorty headers power band

[gmrocket]

Anyone ever do any testing on shorty headers compared to long tube 4 into 1 or tri y's?

On something like 360 to 380 cubes, 1 5/8 or 1 3/4 short primaries dumping into a 2 3/4 or 3" collector,,or pinch ...then into a long swept pipe of the same size, or pinch and megaphone?

[Newold1]

My opinion is there is not huge power or torque in headers period until you either get to big horsepower builds or your exhaust system is a mess to begin with. There is sort of an old outdated legend that headers add huge power to all performance builds. I have put 500-600HP engines on the dyno with stock OEM exhaust manifolds with a 2-1/2" -4ft exhaust pipe and then a nice long tube properly sized header and usually not seen more than 20-25 additional horsepower.

Good well designed and built headers are not $250 -$400 per set out of Summit or Jegs so prepare to spend $800-$1200 for a really good pair.

When the engine build N/A gets cams and heads that benefit more from the scavenging aspect of the header then the benefits are better.

Shorty headers probably in most cases are not worth the cost of the metal they are made of. Their added power is about as worthless as tits on a bull!

As for tri-y headers they can be effective depending on the power band and peak torque range of the engine and tend to be also effective in helping with mid rpm torque improvements on street type performance builds.

Long tube headers now days tend to be to short a description as the use and effectiveness of stepped long tubes, merge collectors and collector sizing and lengths have added a better means of increasing header improvements in the form of added power.

Sometimes just one size tube works best but it's best to talk to some of the better header builders like Kook's Pypes, Elston and Burns to really find a header type , construction and sizing to maximize your application. JMO

[groberts101]

Anyone ever do any testing on shorty headers compared to long tube 4 into 1 or tri y's?

On something like 360 to 380 cubes, 1 5/8 or 1 3/4 short primaries dumping into a 2 3/4 or 3" collector,,or pinch ...then into a long swept pipe of the same size, or pinch and megaphone?

I'd say just about almost everyone here that has experienced limited header availability and/or severe space restricted combo's has tested this at one time or another. Compression and rpm makes a difference in the comparison between the various designs but it's all textbook stuff. You'll give up peak power and the width of the powerband will move the peaks closer together is all.

[grandsport51]

I find that Elston’s
Freely offered advice on these subjects is amazing
And he suggests using his tech info site
http://www.exhausting101.com
Dave B

[engineguyBill]

Not much net difference in power output when comparing off the shelf shorty headers to long tube headers. Basically however, short primary tubes will shift power output to higher RPM and long primary tubes will shift power output to lower RPM.

[groberts101]

Not much net difference in power output when comparing off the shelf shorty headers to long tube headers. Basically however, short primary tubes will shift power output to higher RPM and long primary tubes will shift power output to lower RPM.

LOL.. almost spit my coffee out. They won't even take the same tune much less make the same torque numbers in the whole bottom half of the rev range!

From everything I have seen through the years.. the smaller and lower the engines low speed torque output is to begin with.. the bigger variation in power differences you will see. Not sure.. might have a tiny little bit to do with resonant tuning and reversion tendencies.

[Bryan Maloney]

Dyno'ed a 428 Windsor Ford that was assembled with customer supplied parts.
Small-port iron Pro Top Line heads, Super Victor intake, Comp Thumper type cam. Customer planned on using shorty headers.

With Ford Motorsport 1 5/8 shorty headers that belonged to the dyno owner = 540 hp after tuning

Threw on some old, rusty, cracked 1 3/4 late model stock 4 into 1 headers = 580 hp and about +20 lb/ft more torque than the shortys.

The torque and power peaks were within 200 rpm of each other between the tests.

[Scotthatch]

https://youtu.be/Y7_lSU3D0jw

[groberts101]

Dyno'ed a 428 Windsor Ford that was assembled with customer supplied parts.
Small-port iron Pro Top Line heads, Super Victor intake, Comp Thumper type cam. Customer planned on using shorty headers.

With Ford Motorsport 1 5/8 shorty headers that belonged to the dyno owner = 540 hp after tuning

Threw on some old, rusty, cracked 1 3/4 late model stock 4 into 1 headers = 580 hp and about +20 lb/ft more torque than the shortys.

The torque and power peaks were within 200 rpm of each other between the tests.

Reminds me of the time I finally broke down and swapped Hooker 1-7/8" full length headers onto my 429SCJ motor. I moved from the cast exhaust manifolds which were relatively decently shaped semi-log type designs and had spent considerable time porting them and opening the outlets to match my 3" exhaust. Despite the bigger Crower cam having much more aggressive nature it just wasn't moving much past its 6,800 rpm peak so I figured I'd just fully saturated the cast manifolds peak flow potential. Swapped on the headers and picked up over 40+ horsepower and an additional 300 rpm. More bottom end, more midrange, more topend than I had ever imagined was possible with just a bolt on part. Went from 20 foot long 2nd gear scratches to blowing the tires off on the shift and needing to pedal it, and then on to scratching solid 10 footers in 3rd.

Fun times to say the least and taught me a lot about removing the next biggest cork in any engine build.

[engineguyBill]

LOL.. almost spit my coffee out. They won't even take the same tune much less make the same torque numbers in the whole bottom half of the rev range!

From everything I have seen through the years.. the smaller and lower the engines low speed torque output is to begin with.. the bigger variation in power differences you will see. Not sure.. might have a tiny little bit to do with resonant tuning and reversion tendencies.
[/quote]

Have your Momma wash your shirt soon, as the coffee will stain.

I still maintain that there won't typically/usually be much change in engine performance to be found by just changing from short tube (shelf) headers to long tube (shelf) headers. With that said, however there is significant power to be found by designing said headers as part of the overall combination. For example, a maximum effort, high RPM drag race engine will produce maximum torque/horsepower as long as intake manifold, head ports, camshaft events and header designs are taken into account for this type of engine.
By the same token, a street/strip bracket race vehicle will likely perform better with long-tube, 4-into-1 style headers. It all comes down to correct design/engineering of the total engine/vehicle combination.

[gmrocket]

Dyno'ed a 428 Windsor Ford that was assembled with customer supplied parts.
Small-port iron Pro Top Line heads, Super Victor intake, Comp Thumper type cam. Customer planned on using shorty headers.

With Ford Motorsport 1 5/8 shorty headers that belonged to the dyno owner = 540 hp after tuning

Threw on some old, rusty, cracked 1 3/4 late model stock 4 into 1 headers = 580 hp and about +20 lb/ft more torque than the shortys.

The torque and power peaks were within 200 rpm of each other between the tests.

thanks for the info...do you think the 1 5/8 were way undersized for a 428 to start with, which was why it was down on power/

im talking about a much smaller engine. do you have the header specs and dyno sheets?

[GARY C]

https://youtu.be/Y7_lSU3D0jw

Here is another done by PH, sizes, coatings, long vs short on a BBC.
https://www.youtube.com/watch?v=O1bXPNy1Yn4

[Bryan Maloney]

Dyno'ed a 428 Windsor Ford that was assembled with customer supplied parts.
Small-port iron Pro Top Line heads, Super Victor intake, Comp Thumper type cam. Customer planned on using shorty headers.

With Ford Motorsport 1 5/8 shorty headers that belonged to the dyno owner = 540 hp after tuning

Threw on some old, rusty, cracked 1 3/4 late model stock 4 into 1 headers = 580 hp and about +20 lb/ft more torque than the shortys.

The torque and power peaks were within 200 rpm of each other between the tests.

thanks for the info...do you think the 1 5/8 were way undersized for a 428 to start with, which was why it was down on power/

im talking about a much smaller engine. do you have the header specs and dyno sheets?

Yes, I believe the 1 5/8 shortys were way too small for a 428; even though the HP peak was at only 5800 RPM.
Are there 1 3/4 shorties available for your application?
The old 4 into 1 headers we tried were fairly short, only 28-29 inches long. Longer headers with a good merge collector should have picked the torque up even more.
I'll be visiting the dyno shop in a few days and will get more info.

[groberts101]

Have your Momma wash your shirt soon, as the coffee will stain.

I still maintain that there won't typically/usually be much change in engine performance to be found by just changing from short tube (shelf) headers to long tube (shelf) headers. With that said, however there is significant power to be found by designing said headers as part of the overall combination. For example, a maximum effort, high RPM drag race engine will produce maximum torque/horsepower as long as intake manifold, head ports, camshaft events and header designs are taken into account for this type of engine.
By the same token, a street/strip bracket race vehicle will likely perform better with long-tube, 4-into-1 style headers. It all comes down to correct design/engineering of the total engine/vehicle combination.

No need to be a dick about a logical long tested positive end result and make momma jokes just because all my experiences, and just about everyone else's for that matter, point to the exact opposite of yours. My momma has already passed on and you must think I'm much younger or far less experienced. You'd be wrong again there too.

Maybe your definition of "much change" is the problem causing a perspective issue or something? Gaining even just 5 or 6 ft/lbs if torque across a sizable portion of the powerband for just a 200 or 300 ft/lb lower rpm street motor is still around 2% improvement. Hardly considered to be nothing when the near identical cost between COMPARABLY sized shorty and long tube SHELF stuff is considered.

So after all that I still maintain that shorty's are crap for most anything N/A street except where fitment trumps concern for any potential torque gains. Slight improvements over restrictive cast manifolds but next to squat compared to leveraging the longer tube designs. Otherwise nobody would be spending the extra time and money to design and squish all that extra pipe in there to begin with and everyone would just stick with shorty designs to make life easier without any negatives.

[engineguyBill]

^^^^^^^^^^^^^^^^^^^^^ this ^^^^^^^^^^^^^^^^^^

Looks like we basically agree with each other . . . . . . four tube headers with long (and small diameter) primary tubes are the best choice for n/a street (or street/strip) vehicles. Shorty headers are an alternate choice for vehicles where space limitations and/or ease of installation are major considerations. Short tube length headers (with stepped tube diameter) are the ultimate choice for maximum effort, race-only vehicles that are designed for high RPM (8500 +) usage.

That is what my findings have been, consistently throughout my 50+ years in the high performance industry.