Dyno test soon to follow, EQ Length tubular header

[GLHNSLHT2]

The gain might suprise you. One thing you guys are overlooking a bit is the reversion into the other cylinders from the factory log style manifold. Having the exhaust seperate all the way to the turbo should help other cylinders pick up power.

I've got the old JRB header. The tubes are only 1.25" which are a bit on the small side, 1.5" would be perfect I think but a tight fit for the design. In fact The Pope's exhaust manifold flows 1-5 cfm better than it. But OMG, My true S60 spools up at 1700rpms. 500rpms sooner than it used to. I did change heads and the intake too but I still believe seperating the cylinders made a big difference.

[turbovanman²]

The gain might suprise you. One thing you guys are overlooking a bit is the reversion into the other cylinders from the factory log style manifold. Having the exhaust seperate all the way to the turbo should help other cylinders pick up power.

I've got the old JRB header. The tubes are only 1.25" which are a bit on the small side, 1.5" would be perfect I think but a tight fit for the design. In fact The Pope's exhaust manifold flows 1-5 cfm better than it. But OMG, My true S60 spools up at 1700rpms. 500rpms sooner than it used to. I did change heads and the intake too but I still believe seperating the cylinders made a big difference.

Good points, pics of the JRB and The Pope's manni's!!

[Shadow]

I'm going to be the only one who thinks it'll spool a touch later, by about 300 rpms.

And you may very well be right, but there are a # of things to concider. Velocity, volume, and turbine restriction. The "given" is that the exhaust will have a drop in velocity due to the larger diam runners and thus slow down spool time on the turbo. I believe, however, that this will only hold true IF the turbine is still free flowing with the increase in volume. IF the turbo spools slower, than the stock head/cam flows so poorly than it can't provide the volume to fill the header and the header becomes overkill. IF the turbo spools faster, we know it can't be from an increase in velocity (through the header), so it must be of volume. The ONLY way you can have a drop in manifold/header velocity and have a turbo spool faster is IF the turbine is too restrictive to flow the extra volume. In which case the exhaust gas has no other choise but to increase it's velocity to exit the turbine.

[turbovanman²]

And you may very well be right, but there are a # of things to concider. Velocity, volume, and turbine restriction. The "given" is that the exhaust will have a drop in velocity due to the larger diam runners and thus slow down spool time on the turbo. I believe, however, that this will only hold true IF the turbine is still free flowing with the increase in volume. IF the turbo spools slower, than the stock head/cam flows so poorly than it can't provide the volume to fill the header and the header becomes overkill. IF the turbo spools faster, we know it can't be from an increase in velocity (through the header), so it must be of volume. The ONLY way you can have a drop in manifold/header velocity and have a turbo spool faster is IF the turbine is too restrictive to flow the extra volume. In which case the exhaust gas has no other choise but to increase it's velocity to exit the turbine.

What he said, lol!

[8valves]

However, what happens to the velocity when 3 cylinders are forced to share the same area of flowpath? A stock mani is so short that I'm curious what's going on at WOT as pressure starts to build in the header. What happens to that flow anymore?

Jay, that's one of my hopes as well. I didn't form the tube to the port accurately to leave a reversion wall there. Who knows if it will help, but I'm thinking that this will help get exhaust gas away from the ex. valve so much better that all it can do is help.

A fun test is to use an air gun and blast air through the ports. Do it on a stock manifold into port 1 and you get air coming back out of 2 and 3, a bit on number 1 as well. There is none of this with this design. The column of air is directed dead center into the turbine flange regardless of which port you try. By super non-scientific testing such as that, it would seem as though the exhaust gas is concentrated far better on the goal, turning the turbine as quickly as possible.

[Shadow]

By super non-scientific testing such as that, it would seem as though the exhaust gas is concentrated far better on the goal, turning the turbine as quickly as possible.

I hear what your saying, but keep in mind, this isn't a pinwheel that your shooting air at, you'll still need enough volume to fill the runner for the directional exhaust to have the desired effect on the turbine. Having said that, I obviously believe that the volume present will be sufficient to "make the turbine" a greater restriction and provide slightly faster turbo spool-up!

[8valves]

I hear what your saying, but keep in mind, this isn't a pinwheel that your shooting air at, you'll still need enough volume to fill the runner for the directional exhaust to have the desired effect on the turbine. Having said that, I obviously believe that the volume present will be sufficient to "make the turbine" a greater restriction and provide slightly faster turbo spool-up!

I think so too, I just need to get a clutch disc here ASAP. If the one that is presumably lost by UPS doesn't show on Monday I'm going to be SOL.

This could end up being great for the whole community too, as when the header is tested then the new 02 housing can be done and show what gains are to be had there. When that's done then a modified intake manifold will be an easy 30 minute swap since the bolts are super easy to get at now.

How great would it be if there was an easy to do, bolt up 300 WHP setup for people to do that wouldn't require touching the stock longblock in a TII car? The money that would be spent on a well done head and valvetrain and associated gaskets and bolts/studs etc would easily cover a header, turbine housing, and intake manifold.

[Shadow]

However, what happens to the velocity when 3 cylinders are forced to share the same area of flowpath? A stock mani is so short that I'm curious what's going on at WOT as pressure starts to build in the header. What happens to that flow anymore?

It become a preasure cell, and volume overcomes directional velocity. Not the most efficient by far, but still significant. This is why I made the statement some years ago about the stock ported mani being able to support 500WHP. Not because I didn't think a header could do sinificantly better, simply because it had the appropriate volume and cross-sectional area to do the job.

[Directconnection]

And you may very well be right, but there are a # of things to concider. Velocity, volume, and turbine restriction. The "given" is that the exhaust will have a drop in velocity due to the larger diam runners and thus slow down spool time on the turbo.

This is something I have always believed, too. Bigger should not always be better.... there will be a compromise and a trade-off at a certain volume, just like any other runner shape and form. What drives the turbo is the hot expanding gases. If the exhaust manifold diameter is too large, what do you think happens to those exhaust gases as they are trying to escape? Residual unburned fuel is why the exhaust is expanding STILL... and this drives the turbo, ok? Now... you have "x" exhaust port cross sectional area (or volume) containing this pressure, and when it's exiting, into a larger "y" volume, these exhaust gases expand into the larger runner, losing some of it's energy. Then there's also the simple when is there too much velocity, or not enough factor. I am certain that going too large will not be a good thing. But, how large is too large?

[turbovanman²]

I think so too, I just need to get a clutch disc here ASAP. If the one that is presumably lost by UPS doesn't show on Monday I'm going to be SOL.

This could end up being great for the whole community too, as when the header is tested then the new 02 housing can be done and show what gains are to be had there. When that's done then a modified intake manifold will be an easy 30 minute swap since the bolts are super easy to get at now.

How great would it be if there was an easy to do, bolt up 300 WHP setup for people to do that wouldn't require touching the stock longblock in a TII car? The money that would be spent on a well done head and valvetrain and associated gaskets and bolts/studs etc would easily cover a header, turbine housing, and intake manifold.

Stop posting Aaron, your going to get us all worked up into a frenzy,

Do I here "8valves" new bolt on packages?

[Shadow]

This could end up being great for the whole community too, as when the header is tested then the new 02 housing can be done and show what gains are to be had there. When that's done then a modified intake manifold will be an easy 30 minute swap since the bolts are super easy to get at now.

How great would it be if there was an easy to do, bolt up 300 WHP setup for people to do that wouldn't require touching the stock longblock in a TII car? The money that would be spent on a well done head and valvetrain and associated gaskets and bolts/studs etc would easily cover a header, turbine housing, and intake manifold.

Music to my ears my friend. Keep in mind, I'm just as interested to see what's going to happen as you. MAYBE this will be the start of the NO-BS 8v build-up.

[Directconnection]

I've got the old JRB header. The tubes are only 1.25" which are a bit on the small side, 1.5" would be perfect I think but a tight fit for the design. In fact The Pope's exhaust manifold flows 1-5 cfm better than it.

What is the JRB header? Not talking about the ABM are you? Because I highly doubt ANY highly ported stock exhaust manifold will outflow the unported ABM.

#3 port on the stocker is horrible. 20+cfm difference with it bolted to the head at .500" lift. Unless you have that magical right angle porting tool, it will never come closer than 20cfm to the other runners. I know... I tested quite a few of other people's/vendor's ported stockers on my flowbench. More than 20 cfm w/out the head bolted to it.

[Directconnection]

MAYBE this will be the start of the NO-BS 8v build-up.

Word.... Yo.

[8valves]

This is something I have always believed, too. Bigger should not always be better.... there will be a compromise and a trade-off at a certain volume, just like any other runner shape and form. What drives the turbo is the hot expanding gases. If the exhaust manifold diameter is too large, what do you think happens to those exhaust gases as they are trying to escape? Residual unburned fuel is why the exhaust is expanding STILL... and this drives the turbo, ok? Now... you have "x" exhaust port cross sectional area (or volume) containing this pressure, and when it's exiting, into a larger "y" volume, these exhaust gases expand into the larger runner, losing some of it's energy. Then there's also the simple when is there too much velocity, or not enough factor. I am certain that going too large will not be a good thing. But, how large is too large?

Absolutely. I've learned a lot with secondary diameter setups on turbo cars in the last few months. I built a header for my brother's Talon that had a great flowpath, awesome wastegate prioritization, and long sweeping bends. Worked fine except that it made the car terribly lazy with too large of a secondary before it hit the turbine housing.

It made a ton of power, but it all came on at once. The low boost/low rpm area just sounded dead and flat according to those that were there to watch it.

I've seen this on one other car now too that we're making some design changes with that are drastic and should prove this theory quite well.

Now, I'm curious as to how much the effect will be there when the diamter we're speaking of is only a couple of inches out of the cylinder head? Im sure it still affects it, but I wonder if the 1 3/4" on this header will be more of a burden than a help? Tough to say without building another one with smaller primaries and comparing.

Even if it spools the same, was it because the ID was too large allowing the gasses to cool too rapidly, or was it because the thinwall material didn't retain the heat like the stock cast peice does? Interesting dilemma.

[8valves]

What is the JRB header? Not talking about the ABM are you? Because I highly doubt ANY highly ported stock exhaust manifold will outflow the unported ABM.

#3 port on the stocker is horrible. 20+cfm difference with it bolted to the head at .500" lift. Unless you have that magical right angle porting tool, it will never come closer than 20cfm to the other runners. I know... I tested quite a few of other people's/vendor's ported stockers on my flowbench. More than 20 cfm w/out the head bolted to it.

The JRB is a tube header the mimicks a stock exhaust manifold. Same positioning, but keeps the primaries seperate until the turbine flange.

See here: http://www.pnw-sdac.org/gallery/main...3074&g2_page=1

[turbovanman²]

The JRB is a tube header the mimicks a stock exhaust manifold. Same positioning, but keeps the primaries seperate until the turbine flange.

See here: http://www.pnw-sdac.org/gallery/main...3074&g2_page=1

Like yours but, with the flange moved over.

How do you think yours will fit with power steering or have you removed it?

[t3rse]

Like yours but, with the flange moved over.

no, the JRB is not equal length....

[turbovanman²]

no, the JRB is not equal length....

Well durr, if you move the flange over on the JRB, its becomes equal length.

[turbovanman²]

I tried blowing air thru a TIII manifold and wow, I thought it would be ok but not.

Blowing thru 1, it comes out of 3 quite alot and a bit out of 4.

Blowing thru 2, it comes out of 3 badly and 4 a bit.

Blowing thru 3, 4 is bad, 1 and 2 a bit.

Blowing thru 4, 1 and 3 are bad with a bit out of 2.

This is with NO turbo, lol.

[GLHNSLHT2]

What is the JRB header? Not talking about the ABM are you? Because I highly doubt ANY highly ported stock exhaust manifold will outflow the unported ABM.

#3 port on the stocker is horrible. 20+cfm difference with it bolted to the head at .500" lift. Unless you have that magical right angle porting tool, it will never come closer than 20cfm to the other runners. I know... I tested quite a few of other people's/vendor's ported stockers on my flowbench. More than 20 cfm w/out the head bolted to it.

What Aarron said +
JRB is Jessie R. Buhr. Made it years ago, goal was to provide a tube header and keep the turbo in the stock location. The execution could of been slightly better but the construction is top notch. I had it coated with the 2000 degree+ stuff hoping it'll live for 15-20 years. I'm really happy with it.

Any pics of the Alabama Man?? header?

We tested it and The Pope's Ported manny off port #2.