Tri-Y Headers for torque?

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chryslercruiser

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I'm under the impression that Tri-Y headers help the midrange on a V8. Would they do the same on an inline 6? I'm looking for off idle to maybe 4500RPM...

I would be building my own, probably using a Jeep 4.0 tubular exhaust manifold, and some other collected parts to create this.
 
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There are many theories about what works with various combinations.
Pete McNicholl who was a member of the Ramchargers was successful with tuning the exhaust system.
Here is his dragster from the early sixties.
The collectors are way down the head pipes.
225dragster 2.JPG


His Willys had a form of Tri-Y that he made.
I have these that were made years ago, back yard Tri-Y.
My Tri-Y Headers.jpeg
 
Hyper_pak said:
There are many theories about what works with various combinations.
Pete McNicholl who was a member of the Ramchargers was successful with tuning the exhaust system.
Here is his dragster from the early sixties.
The collectors are way down the head pipes.
View attachment 1716227167

His Willys had a form of Tri-Y that he made.
I have these that were made years ago, back yard Tri-Y.
View attachment 1716227171
Click to expand...
Pete had tri-y's on his willys?

I like home brewed solutions... What would happen if the center two cylinders were connected, numbers 2&4, and then1&6, so there are 3 sets of 2 cylinders.. and each is connected.. then the three collectors merge into one...?
 
Yes, I tried to find a picture, I will keep looking for the image.
I just read something yesterday about a different header pairing.
I am not sure how any of them might work.
I like the 6 into 1 deal myself, that seems like a self scavenging deal to me.
My headers are 1-2-3, 4-5-6, kinda boring.
Slantzilla Bed o Snakes.jpg


Bed of Snakes (2).jpeg
 
chryslercruiser said:
Pete had tri-y's on his willys?

I like home brewed solutions... What would happen if the center two cylinders were connected, numbers 2&4, and then1&6, so there are 3 sets of 2 cylinders.. and each is connected.. then the three collectors merge into one...?
Click to expand...
You're trying to maintain a wide power band, and good from down low, right?
So the big thing will be velocity out of the exhaust ports. The least cheats and the smoothest bends. When the tubes start to joint, try not to go bigger than needed.

Dig around and see if Elston posted anyhting about straight sixes. keep in mind most of his work was for racers - either roundy round or 1/4 mile straight.
 
On V8 engines, it has been shown many times to be BS. Where this myth came in I don’t know and how it still persists after many dyno tests showing it not to be true is nearly amazing.

The tri Y headers are fine for use but I see no benefit that would have me use them in a torque search for any reason what so ever.

I am not against them ether.

On a inline 6, I have no idea.
 
Idle to 2000/2500 rpm there's a few things to do to gain torque in this area but it's mainly displacement and cr, since those are somewhat fixed by the engine choice and fuel type. Your mainly trying not to lose here while trying to gain 2500-5000+ rpm range.

Head flow is the biggest cork on /6 power.
 
Mattax said:
You're trying to maintain a wide power band, and good from down low, right?
So the big thing will be velocity out of the exhaust ports. The least cheats and the smoothest bends. When the tubes start to joint, try not to go bigger than needed.

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Dig around and see if Elston posted anyhting about straight sixes. keep in mind most of his work was for racers - either roundy round or 1/4 mile straight.
Click to expand...
Yes, and now that you say it I remember reading here that DD put the front-rear "Y" back near the rear axle and it gave good off idle power.. that is what I am looking for.. Then how to size it so it does not become a cork at 4500.. but realistically I am in the 1500-3000 range and most often 1800-2800..

i will go look up the speed talk topic and see what I discover. Thanks!
 
chryslercruiser said:
Yes, and now that you say it I remember reading here that DD put the front-rear "Y" back near the rear axle and it gave good off idle power.. that is what I am looking for.. Then how to size it so it does not become a cork at 4500.. but realistically I am in the 1500-3000 range and most often 1800-2800..
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But generally at part throttle, unless your pushing the throttle over 1/2 - full to do normal driving around town your already making more idle-3000 rpm power then you use.
chryslercruiser said:
i will go look up the speed talk topic and see what I discover. Thanks!
Click to expand...
 
chryslercruiser said:
Yes, and now that you say it I remember reading here that DD put the front-rear "Y" back near the rear axle and it gave good off idle power.. that is what I am looking for.. Then how to size it so it does not become a cork at 4500.. but realistically I am in the 1500-3000 range and most often 1800-2800..

i will go look up the speed talk topic and see what I discover. Thanks!
Click to expand...
Interesting that Dutra did that.
Maybe on the weekend if I'm not too busy I'll look for my newer copy of pipemax. 'Newer' but not even close to the latest. I've never run a model for a six on it - not even sure if the older version will do it. I'm pretty sure Meaux's new version do.

Have fun at speed-talk. You can spend lotsa time there! Well worth joining (you don't get spammed) just to read the advanced engine forum. Especially the begining of this one by Calvin Elston
Log Manifold lessons! - Page 21 - Don Terrill’s Speed-Talk

My header build is in the regular engine forum.
 
273 said:
Idle to 2000/2500 rpm there's a few things to do to gain torque in this area but it's mainly displacement and cr, since those are somewhat fixed by the engine choice and fuel type. Your mainly trying not to lose here while trying to gain 2500-5000+ rpm range.

Head flow is the biggest cork on /6 power.
Click to expand...
Geee,....& I wonder what dynamic phenomenon could greatly increase the performance & efficiency of a lacking cylinder head, hmmmmmm.....:rolleyes:
 
MidnightSwinger said:
That’s forced induction, not a dynamic phenomenon, such as the exhaust scavenging.
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I know what answer he was looking for :)

Really what kind of real world torque gains are we talking here ? No matter what type of header, especially in the idle-3000 rpm where we spend very little time at full throttle and torque at these rpm only translates to 12-59% hp per lbs-ft of torque.

If the OP don't care about dollar value and wants to do it as an experiment with very little real world gains that kool. It just seems like there's an assumption there's a lot to be gained, just trying to put expectations in perspective.
 
"Dynamic Phenomenon means a continuous, energetic and positive process of change and progress."

seems like force induction fits.
 
273 said:
I know what answer he was looking for :)

Really what kind of real world torque gains are we talking here ? No matter what type of header, especially in the idle-3000 rpm where we spend very little time at full throttle and torque at these rpm only translates to 12-59% hp per lbs-ft of torque.

If the OP don't care about dollar value and wants to do it as an experiment with very little real world gains that kool. It just seems like there's an assumption there's a lot to be gained, just trying to put expectations in perspective.
Click to expand...
So you are just being a cunt?
 
MidnightSwinger said:
So you are just being a cunt?
Click to expand...
How?

Cause I don't want to OP waste a bunch of money to see little to no gains in the area he seems to be looking for? Or at least to do it with knowing the possible down sides.
 
MidnightSwinger said:
Now look up the definition of phenomenon and you might learn something.
Click to expand...
I don't care if force induction is or isn't a Dynamic Phenomenon, wasn't the point I'm trying to make, but it does seem to fit the meaning :)
 
chryslercruiser said:
Pete had tri-y's on his willys?

I like home brewed solutions... What would happen if the center two cylinders were connected, numbers 2&4, and then1&6, so there are 3 sets of 2 cylinders.. and each is connected.. then the three collectors merge into one...?
Click to expand...
Tri - Y on a V8 separates the 2 cylinders on each side that fire 90° apart. What a regular manifold or shorties does is allow one of the two close firing to push high pressure exaust past the closing valve of the previous cylinder. This is hot exhaust that heats and dilutes the incoming air/fuel charge and aggrivates detonation. The collector sees a long space between exhaust pulses, then a 180° followed by two 90° apart that it senses as one larger cylinder. The V8 TRI- Y does improve low and mid range torque without a major drop in high RPM. TRI - Y generally function best below 7,000RPM. If running higher RPM 4 into 1 is best.
What you refer to TRI - Y on an inline six is really 6 into 2 into 1, and functions similar to 4 into 1 V8. In each secondary the firing pulses are 240° apart, so the exhaust does not interfere with the other 2. In the headers in the photos, I would not wish to hazard a guess on pulse tuning effectiveness. Primary tube lengths are not as important as the collector length and the "open air" volume to create the reversal for pulse tuning.
 
chryslercruiser said:
I'm under the impression that Tri-Y headers help the midrange on a V8. Would they do the same on an inline 6? I'm looking for off idle to maybe 4500RPM...

I would be building my own, probably using a Jeep 4.0 tubular exhaust manifold, and some other collected parts to create this.
Click to expand...
Get a copy of Phillip H Smith's book, The Scientific Design of Exhaust and Intake Systems. If you get it and read it, you better have your thinking cap on snug but not too tight. It gets a bit deep in places.
 
MidnightSwinger said:
So you are just being a cunt?
Click to expand...

He gets that every so often and ignores it as if your the jackass and loose your cool and/or forgot your meds for the day. He is blind to the fact. He hasn’t built **** ether but processes like a parrot what he reads here like he knows everything.
 
Dale Davies said:
Get a copy of Phillip H Smith's book, The Scientific Design of Exhaust and Intake Systems. If you get it and read it, you better have your thinking cap on snug but not too tight. It gets a bit deep in places.
Click to expand...
Thanks for the recommendation..
 
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