Nameless Performance Equal Length Stepped Header

[Jason@Nameless]

Originally Posted by rusty959

Awesome can't wait to see it. Personally, I think where the battery goes is the least of anyone's worries. Lithium batteries are stupid small if you don't want to give up much space elsewhere.

I'll toss the GT2876R in there tonight or tomorrow while the battery is out for dimensioning of the battery box and take some photos. Just got the cold side in a few days ago. It's effing gigantic for a GT28. Have some other thoughts on turbo placement and they're quite interesting. Not exactly conventional.

Jason

[EZWood]

Hey Jason,
To your knowledge, has anyone been experimenting with non waste gate turbos, such as the ones going on modern diesel engines. The reason I ask is I have a gt3782v, I was thinking despite the smaller displacement on these cars, this technology would allow spooling very low in the rpm range, and won't max out on the top end. What are your thoughts on this?

[Dimman]

Originally Posted by Jason@Nameless

We're also going to add one other thing to the new catless design (just finished the 125hz band pass resonator for the downpipe and switched over to the new header) - we're going to run a 1.75" bore flange and leave a slight anti-reversion step between the cylinder head port and the header. Any thoughts on this? Also contemplating some of the secondary collector options. Optimally we'd have a 14" long megaphone collector, but we've only got about 7-8" from the collector of the secondaries to the flange. Kindof on the fence in regard to how to proceed on this. We do have conical forms that we can use, but getting any sort of megaphone design back into that flange is going to make for a ridiculous transition. Hmmph. Thoughts? I was going to call in some favors with some of our friends in the morning over at Cone Engineering and Burns to see what their thoughts were. Might just be best to not even evaluate the megaphone option and go instead with the optimal straight collector size and bring it back down to 2.5" at the flange. Homework time.

Jason

The anti-reversion thing is something I'm a bit unsure of. In big cammed OHV they may be useful but in our case it is the AVCS can do the same job. At low rpm/low intake inertia they can close intake earlier to lessen or eliminate charge getting pushed back out by rising piston. And at periods of 'bad' acoustic scavenging they can eliminate overlap so the exhaust wave can't transfer the intake.

So assuming we can control it this way with stock duration cams, all the step will probably do is create turbulence and some flow loss.

But I would rather test it anyways, because it could actually be used to scavenge at higher rpm if it can generate it's own acoustic pulse from the change in area. If you do test it, I would put the step at ~5" from the valve to start. I was thinking of this myself and had my welder practicing. I made the steps out of billet 304 on the lathe that was machined to smoothly accept the small inlet and large outlet. I could machine the transition between the two at any angle I had enough length for with a boring bar on the compound rest. They were then all press fit together and he lap-fused both sides. We wanted to test for flow (bench) and acoustics (on dyno) so we could identify where the gsins were coming from. But we never got good shop access and dropped our flow-bench project, too...

[R/TErnie]

^ way easier to actually weld the tube slipped over the other one and then welding it while it's backpurged. Makes a really nice transition without having to turn parts.

[Dimman]

Originally Posted by R/TErnie

^ way easier to actually weld the tube slipped over the other one and then welding it while it's backpurged. Makes a really nice transition without having to turn parts.

You're talking about just a .125" diameter increase, right? We wanted to test bigger, and different angles.

[Jason@Nameless]

Originally Posted by EZWood

Hey Jason,
To your knowledge, has anyone been experimenting with non waste gate turbos, such as the ones going on modern diesel engines. The reason I ask is I have a gt3782v, I was thinking despite the smaller displacement on these cars, this technology would allow spooling very low in the rpm range, and won't max out on the top end. What are your thoughts on this?

Are you serious? I have a pair of GT1749V's that I'm putting on my Alfa Romeo Spider 2.0L Nord engine!! Yes I am a big fan, I hate how they're controlled with the robbie the robot vacuum diaphragm. I was thinking of doing either a cable drive or linkage drive to a linear actuator to sync the two. Before you go all WTF on me, I just want to do this for fun, I know a proper turbo would be better hands down in this application (the Alfa Nord engine). Also have a Holset HE351VE that a customer and I have been wanting to play with on either a EJ25 or flat six.

So yeah, I am a big fan of VGT turbos. I think they're pretty damn slick and I think if you get one sized properly you could do some really nifty stuff on an engine like this. My only qualm with them is that because they're not made extensively for aftermarket use, you end up having to source a proprietary design like the Audi TDI 1749's and there is little to no data on their compressor map or details of the range of the VGT systems on them. The only charts I have for the HE351VE (ours is heavily modded with a different compressor wheel, porting, etc) are sparse at best as well.

But hell, the 351ve would fit where the battery goes. Entirely. Haha. It's the size of a pumpkin. What's the 3782V off of? Powerstroke?

Do you know how the vanes are controlled? Personally I prefer the holset because it's got the gated design and less moving parts, but you have to yard off the CAN controller and directly drive the stepper system.

Jason

[serialk11r]

Originally Posted by Jason@Nameless

I was thinking of doing either a cable drive or linkage drive to a linear actuator to sync the two.

Whoa, are you talking accelerator pedal controlled wastegate? That is actually quite cool. Would reduce part load pumping loss too, if set up correctly.

[Jason@Nameless]

Well I was considering using a simple cable drive to sync the two variable vane bellcrank arms on the GT1749V's and then driving that cable with a linear actuator, but that linear actuator would be driven by a multi-axis map using RPM/Load/Boost, maybe even shaft speed. This could control the system to reduce pumping loss and literally target the compressor island peak as well. If you had a system that could have a four or five axis map (think a map inside of each of the cells of a map inside of each of the cells of a map) and then could write an algorithm to collect data during driving in order to control targeting, you'd have a pretty badass system overall. Between John and I and our two consulting electrical/firmware engineers, we talk about crap like this all the time, but they're both busy working for supercar manufacturers and consumer electronics manufacturers and we're busy making...exhausts. I love what pays the bills and I know we make some of the best performing and sounding exhaust systems out there, but I just wish we had all of the time in the world to play with things like this and bring them to functional prototypes. It's unfortunate that niche corners of the market rarely get the time and effort invested to bring these wild ideas to market. This is exactly why I love automotive engineering and performance product design - the sky is the limit for novel ideas that would work. It's really sad to see that most of the wild ideas discussed in the literature (SAE Papers, etc) are written by students and instructors at engineering schools. They're the only ones who seem to have time to expend on these things.

Boo!

Jason

[Calum]

So then use an electric motor to drive the turbo shaft during low engine speeds. Get the crossover from motor to turbine drive right and the control right and you could toss the throttle body to the wind. More pumping losses reduced.

Jason, I'm actually jealous of your job. If I ever get back to the west coast I'm taking a drive down to meet you and see the shop.

[serialk11r]

Originally Posted by Calum

So then use an electric motor to drive the turbo shaft during low engine speeds. Get the crossover from motor to turbine drive right and the control right and you could toss the throttle body to the wind. More pumping losses reduced.

That doesn't get rid of the throttle body...if you're thinking of using the compressor to restrict the intake, it won't be enough.
However with that configuration you can get excess turbine power converted into electrical power

[Jason@Nameless]

Originally Posted by serialk11r

That doesn't get rid of the throttle body...if you're thinking of using the compressor to restrict the intake, it won't be enough.
However with that configuration you can get excess turbine power converted into electrical power

Ok back on topic. I know I jacked my own thread...I need to start a turbo discussion thread.

Got the helmholtz resonator done on the downpipe, makes a substantial difference in high load, 4krpm drone. Have a few tweaks to make to it and then we will be doing a second test today.

The 4-2-1 catless header is almost done as well.

Jason

[Tainen]

When does the new downpipe go on sale? edit: nevermind, I see you have two downpipes on the site now, the stock replacement, and the one that replaces both the overpipe and the downpipe. interesting. And I'm guessing you'll also put one up for sale that has the resonator added in there for people that want that buzz/drone taken out? (seems like some people want the louder sound, so offering it as an option is a good idea)

[Jason@Nameless]

It's on sale right now without the helmholtz option. Just need to add that in as a ~$40 option.


Jason

[EZWood]

Originally Posted by Jason@Nameless

Are you serious? I have a pair of GT1749V's that I'm putting on my Alfa Romeo Spider 2.0L Nord engine!! Yes I am a big fan, I hate how they're controlled with the robbie the robot vacuum diaphragm. I was thinking of doing either a cable drive or linkage drive to a linear actuator to sync the two. Before you go all WTF on me, I just want to do this for fun, I know a proper turbo would be better hands down in this application (the Alfa Nord engine). Also have a Holset HE351VE that a customer and I have been wanting to play with on either a EJ25 or flat six.

So yeah, I am a big fan of VGT turbos. I think they're pretty damn slick and I think if you get one sized properly you could do some really nifty stuff on an engine like this. My only qualm with them is that because they're not made extensively for aftermarket use, you end up having to source a proprietary design like the Audi TDI 1749's and there is little to no data on their compressor map or details of the range of the VGT systems on them. The only charts I have for the HE351VE (ours is heavily modded with a different compressor wheel, porting, etc) are sparse at best as well.

But hell, the 351ve would fit where the battery goes. Entirely. Haha. It's the size of a pumpkin. What's the 3782V off of? Powerstroke?

Do you know how the vanes are controlled? Personally I prefer the holset because it's got the gated design and less moving parts, but you have to yard off the CAN controller and directly drive the stepper system.

Jason

Depending on the model, they are either controlled by vacume, of by some sort of servo. It has been a while since I have read up on it, but if this is a direction that you want to go, you should check out tdiclub.com. It's a Volkswagen forum, there is a wealth of information about the vnt controllers. Twin 17's would Make some serious power, i want to say that the turbo that was on my jetta tdi was a Borg Warner kp39 which is pretty small, about the size of a gt15. The 3782 is a power stroke turbo. I've had it for a couple years, and I'm getting to the point to where I just want to sell it, I think it would make for a pretty viable turbo. I read somewhere about a guy putting one on a 2.0 Mazda, and he claimed fifteen psi at three thousand rpm.