Don Terrill’s Speed-Talk

For tubing
Check out performance tube bending
And for cones of any type cone engineering.

Ptb is local and the tube is so cheap I just chop and fit. If it's wrong I throw it in the barrel and grab another u.

I like to use pieces of bends with the leg rather than bend straight bend less welds look cleaner and more professional but uses up a lot of u bends

I'd also recommend turning adapters from thick wall steel pipe to taper from 1 3/8 ports to 1.250.

Thank you all very much for the feedback. Its been a good learning experience and I am not done. I did find a 1-3/8 to 2" transition cone after I posted this morning at SPD in Sacramento. At least they list it on their website, but the price sheet doesn't show it. Will call them Tues.

englertracing wrote: ↑Sat May 29, 2021 4:49 pm For tubing
Check out performance tube bending
And for cones of any type cone engineering.

That is a good source for U bends! I purchased my bends from Stahl on closeout when they closed and they still charged me way more than what that place is charging.

donforeman wrote: ↑Sat May 29, 2021 6:52 pm Thank you all very much for the feedback. Its been a good learning experience and I am not done. I did find a 1-3/8 to 2" transition cone after I posted this morning at SPD in Sacramento. At least they list it on their website, but the price sheet doesn't show it. Will call them Tues.

Spd will leave you with no arms and no legs....
Expensive...
I buy 20g from them and it's like 40$ + per bend.
Ptb is all 16g

A good program is conelayout.com
Can print and cut the paper out /roll it, if you want do any mock up.

englertracing wrote: ↑Sat May 29, 2021 7:16 pm Spd will leave you with no arms and no legs....
Expensive...

Yes, I will use PTB in the future I like saving money! I did not find the 1-3/8" to 2" transition though at PTB. So far only SPD has it shown and its not on their price list so it may not even be there. Small cones are harder to find, even Cone Engineering starts at 1-1/2"

brentry wrote: ↑Sat May 29, 2021 8:57 pm A good program is conelayout.com
Can print and cut the paper out /roll it, if you want do any mock up.

Cool thank you for the tip.

MetricMuscle wrote: ↑Thu Dec 31, 2020 1:12 pm The new Nissan Titan 5.6 liter gasoline engine sports "YUGE" 2" exhaust ports. The only thing I've seen about why is that it was done to improve exhaust manifold life, or something.

I was not aware port size could relate to manifold life. I am building a Nissan VK45, the 4.5 liter engine that the Nissan VK56 design is based on. It has slightly smaller 39mm (1.5 inch) diameter ports. It has been suggested they are almost too big yet the head flow on the exhaust is only 65% of the intake.

Rob-bb wrote: ↑Sun May 30, 2021 3:39 pm
I was not aware port size could relate to manifold life. I am building a Nissan VK45, the 4.5 liter engine that the Nissan VK56 design is based on. It has slightly smaller 39mm (1.5 inch) diameter ports. It has been suggested they are almost too big yet the head flow on the exhaust is only 65% of the intake.

Me either! I actually have an FX50S with the VK50VE engine. I wish it had the smaller oval exhaust ports of the previous generation V8's.

It also occurred to me as I was practicing thinking outside of the box, what if the 2" round exhaust port is not a 0 degree perpendicular cross section of the exhaust port, rather it is a 45 degree cross section of the exhaust port and the manifold or header is supposed to be designed accordingly?



Make for a better short side radius, like raising the exhaust port sorta.

MetricMuscle wrote: ↑Mon May 31, 2021 7:31 pmMe either! I actually have an FX50S with the VK50VE engine. I wish it had the smaller oval exhaust ports of the previous generation V8's.

It also occurred to me as I was practicing thinking outside of the box, what if the 2" round exhaust port is not a 0 degree perpendicular cross section of the exhaust port, rather it is a 45 degree cross section of the exhaust port and the manifold or header is supposed to be designed accordingly?

Do you have any more info on size of port vs manifold life?

As for the port idea, the service manual for VK45 engines has a cross section drawing of the head, and it feels like looks when I poke around inside it

Rob-bb wrote: ↑Mon May 31, 2021 7:43 pm

MetricMuscle wrote: ↑Mon May 31, 2021 7:31 pmMe either! I actually have an FX50S with the VK50VE engine. I wish it had the smaller oval exhaust ports of the previous generation V8's.

It also occurred to me as I was practicing thinking outside of the box, what if the 2" round exhaust port is not a 0 degree perpendicular cross section of the exhaust port, rather it is a 45 degree cross section of the exhaust port and the manifold or header is supposed to be designed accordingly?

Do you have any more info on size of port vs manifold life?

As for the port idea, the service manual for VK45 engines has a cross section drawing of the head, and it feels like looks when I poke around inside it

No, I don't have any more info regarding increased manifold life. I have found very little info on the VK50VE or the current generation Titan engine which also has 2" exhaust ports. I barely remember how it was worded, maybe Nissan had made the comment, IDK.

I'd love to find a cross section drawing of the VK50VE head or even just better pictures of the exhaust port. The exhaust manifold is so ugly it makes me angry to look at.

MetricMuscle wrote: ↑Tue Jun 01, 2021 11:38 am No, I don't have any more info regarding increased manifold life. I have found very little info on the VK50VE or the current generation Titan engine which also has 2" exhaust ports. I barely remember how it was worded, maybe Nissan had made the comment, IDK.

I'd love to find a cross section drawing of the VK50VE head or even just better pictures of the exhaust port. The exhaust manifold is so ugly it makes me angry to look at.

I hear you on that, this is the factory exhaust on the VK45DE, the picture doesn't do it justice, it looks like it was made in a high school welding class. The second picture is looking down the runners, they have these lips protruding up to 4mm into the flow on both sides of the runner, you can only see one in the picture. Usually one side is worse than the other, say for example 2mm on the top and 4mm on the bottom.

OK back on topic or close to it...
I finished my first merge collector. Its not pretty, but I think it will function just fine. After I got it done yeastersay, I thought about redoing it for a better look, but the project has been sitting in my shop for 14 years. At this point I think I can always redo the header later after its back on the track using the experience and welding practice I got doing this one. I did end up ordering a few things from PTB already so thanks to the person who posted that. This has been a learning experience. I feel comfortable practicing tig on exhaust as if a weld fails you get some more noise and not much else. So my question, on cone engineering's website they recommend using the next size up tubing in 18g as slip fit connectors. I have some 1-1/2" 18g but it seems to fit on the 1-3/8 OD very loose. There would be leaking if assembled as is. What are my options? I could put a small bead of high temp silicone around each tube or is there a way to shrink the tube id slightly for a better slip fit? I could order some thicker wall and cut the id on my lathe? The plastic bits have some slop in them and sag so the real routing will not be as close to the v belt pully like shown in the picture.

All tacked up. I still have a lot of welding practice ahead and have the collector cone and a support bracket for the collector to add. It was a learning project and I learned a lot. A lot of what I originally was thinking about design wise at the start of this thread went out the window when I tried to apply it on the car. Thanks for the advice. I already got one order from PTB, their prices are great.