Square Headers??

[racer189]

I was talking to a friend today that was telling me about a company he talked to down at the recent PRI show in Orlando that was making square headers, and they claimed significant improvements in torque. Does anyone else know anything about either this company or the technology itself? As I understand it, square headers would/should be very inefficient? Both the primary tubes and collectors were square.

[MadBill]

I've seen a rectangular collector turn to confetti in short order; the flat walls vibrate/fatigue in minutes or even seconds...

[putztastics]

I'd like to see some visual evidence that someone has actually made square tube headers.

A dirt track racer I know asked about square headers, wanted me to build some. He had heard from another dirt racer who was at a party down south somewhere at which a NASCAR header builder was. This guy was telling everyone some NASCAR headers were square tube inside round tube. And yes they were supposed to be great. I told the dirt racer the only way square headers would make sense to me is if I were on drugs, like his fellow racer was.

Dirt racers can be really weird sometimes.

[racer189]

I'd like to see some visual evidence that someone has actually made square tube headers.

A dirt track racer I know asked about square headers, wanted me to build some. He had heard from another dirt racer who was at a party down south somewhere at which a NASCAR header builder was. This guy was telling everyone some NASCAR headers were square tube inside round tube. And yes they were supposed to be great. I told the dirt racer the only way square headers would make sense to me is if I were on drugs, like his fellow racer was.

I guess they had a set of square tube headers at their booth. My friend tried to describe to me how they were made and he said that they were "a square tube inside a round tube", like the dirt track racer described.

I also don't know about the square header concept but I try to keep an open mind, as many great advances in science and technology were discovered by accident while someone was experementing with a never tried/unproven or previously tried and rejected concept and they ended up discovering something else that was completely unrelated.

Occasionally we try something that we are 99% sure won't work, just in case we end up finding that 1%. From what I've read, many successful race teams sometimes follow this same strategy, just in case. [/i][/quote]

[SchmidtMotorWorks]

I can see how the flow might be better in the turns but worse on the straight sections.

[rooster]

They were at PRI. Apparently used on a race-winning IMCA style mod. They were square, fabbed with no corner radius whatsoever. Don't know about their performance, but they were butt ugly!

[larrycavan]

Now how does a square shaped anything out flow a round thing of equal diameter?

[TRN]

Just for example, a 1.75 round tube has 2.405 area, a 1.75 square tube has 3.063 area. What do you mean by diameter? The round tube has 5.498 circumference and the square tube has 7.0 circumference.

I remember reading about a NASA duct design for minimum turbulence that used a trapezoid shape (can't seem to find it...).

I wonder whether surface friction matters? If round tubes are so critical for headers, why aren't they critical for intake ports?

Where do you find thin wall square tube?

[beth]

Imagine a round tube fitted tightly with a square tube inside. Imagine the round tube was sized larger to produce roughly the same volume and flow of the usual empty round tube in this application. You would have essentially one square and 4 smaller D shaped ports to utilize for exhaust blow down. How would this affect the reversion pulse?



beth

[putztastics]

They were at PRI. Apparently used on a race-winning IMCA style mod. They were square, fabbed with no corner radius whatsoever. Don't know about their performance, but they were butt ugly!

This thread is worthless without pictures!

The set I was asked to build was for an IMCA mod.

I was under the impression the round tube was to hide the use of square tube. Of course reason for hiding the square tube would be so others didn't figure out why you had such a massive performance increase.

Beth I see lots of potential with your suggestion, just think of the dyno time one could spend trying all the different inner tube lengths, I mean the headers might perform best with the square tube at say 1/2 the total primary tube length.

Be easier to try this on a single cylinder first....

[putztastics]

Well, if the square tube was fit in straight sections of round before bending it might not be too hard to build them. The bender would bend everything at once. I don't know how you would control the orientation of te the square tube at the head and collector, there would be a few pieces of scrap I think.

[2.2=8]

Think heat retention.

[beth]

The tubes would have to be bent seperately, with a square mandrel in the square tube. You would have to use only short sections, no U tubes or J tubes. This could be a possible way to detect this. Wow just thinking about that, how could you make headers if you could not rotate the sections? You can only rotate 90 and 180 degrees with square.



beth

[putztastics]

I though about all that beth, that's when I decided it would probably seem like a lot better idea if I wasn't sober.

but they were butt ugly!

Hmmmm, Made while stoned?

Warren, you got square tubes on that 2.2? If not you gonna try it?

[2.2=8]

Warren, you got square tubes on that 2.2? If not you gonna try it?

Yup Jesse, going to try it on your dyno.