1023 Diesel Shop Talk

Ep. 64 | My 205/30 Smoke to Much at Low RPM

November 23, 2023 Dustin Hogate Season 2 Episode 64
1023 Diesel Shop Talk
Ep. 64 | My 205/30 Smoke to Much at Low RPM
Show Notes Transcript Chapter Markers

 1023 Diesel is a comprehensive diesel repair shop situated in Palmer, AK. While we maintain these videos/podcasts for archival purposes, please note that 1023 Diesel has ceased online parts sales, build support, and tuning services.

For local repairs, you can conveniently schedule an appointment through our website: 1023diesel.com.

For information related to the host, Dustin Hogate, please visit his personal website, as he is no longer affiliated with 1023 Diesel:
 dustinhhogate.com

Dusty:

Hey guys, welcome to Episode 64. The real Episode 64. If you listen to the last show, you will know that I misspoke. So anyway, it doesn't matter, numbers are numbers. Happy Thanksgiving, you guys. Have a fantastic Thursday. Enjoy some turkey or, if you're wise, maybe something a little bit better than turkey. I think it might have been a plague. It might have been a plague that made everybody eat turkey to begin with, but there's nothing good about turkey. Nothing Like chicken's not great, but turkey is way worse. So anyway, we're having chicken instead of turkey this year and most of my friends are having things like good stuff, like tacos, instead. But here's the deal. Today's show is on common problems, common issues that we run into and that's around turbo sizing, injector sizing, towing with your 7.3. And we really should just turn this into the 7.3 diesel show. Vaughn worked on this way too late getting the episode prepared, and I feel kind of bad. I feel sort of bad that I kept him up late, but he did, he pursued, he worked on it until about midnight and that's his time. So I have it's about midnight here and I'm going to finish this up We'll get it out. So happy Thanksgiving for real, for me and for you, and today's show is about choosing the right turbo size. When you go too big, what happens? What are the benefits and the downsides to a turbo that's larger than stock? Or when you go way too big, what happens? So good show, enjoy it. It's pretty short, it'll be about 20 minutes. We'll talk to you guys on the next side. Oh, by the way, if you're not signed up for our email, like our mailing list, you're going to get offers from mailing list and you're tired of seeing emails. But seriously, I have spent the last two and a half three months studying how to send emails that actually are useful and our emails, just going to say it, they're fire. They're fire. Not all of our automated emails are updated yet, but they will be. But our mailing list, they're awesome. They're actually worth listening to, cause I was like how do we send emails that people want to read and they give them something worth reading? You should sign up. You seriously should, like right now. You should sign up because we don't send them frequently, but when we do, they contain lots of good information that doesn't cost you anything, just like the show. So if you like the show, subscribe, listen now no-transcript.

Dustin:

Got a kill devil diesel, stage two, long block, motor running full-force, 205, 30s with a KC 300 X stage two, turbo. Your ideas good, good list, change something up. What, what do you?

Dusty:

think Okay, so You've already done a bill. Devart, you haven't? It looks like you had a fuel system. That was on your list already, right?

Dustin:

Right, yeah, I'm running the irate Regulated return system.

Dusty:

How long have you had this built together? Have you been driving it for a while, or is it still in the works?

Dustin:

It's. I mean it's still in the works. I've Probably got 2,000 miles, 3,000 miles on the motor. Not gonna say it's like last week build, but I mean it's so what exactly can I help you?

Dusty:

You're just looking for whether the parts work well together. That's, that's what. That's all you're looking for.

Dustin:

Well, I mean, but yeah, do they work well together? Do I need to drop to a lower injector? I mean, just for my? I mean I'm trying to get 450 ish, maybe, if I can with those injectors. If not, do I need to step down? Do I need to go to a bigger turbo to get where I need to be? Just what I Mean, if that's kind of input you can give me, or not, really, or well, but let's start with this.

Dusty:

What do you use the truck for?

Dustin:

it's a daily. But then I hook up to a 14,000 pound fifth wheel and tow it from To the beach or to the mountains up through the mountains Appalachian mountain stuff like that.

Dusty:

Have you done that? Since you did, since you started the build, or since you got it together? No, no. So here's what matters. At the end of the day, this is what matters. There is no such thing as a right build or a wrong build, it only matters. Does the truck function the way you want it to? You know, are you happy with the build? So I Mean there's. There's certainly nothing wrong Like, if we're just talking the pairing of parts. There's nothing wrong with the. You know, 205, 30 Casey stage to drop in. You got a, you know I rate fuel system to match. It sounds like you got a great engine. You know, kill double great way to go for a, for a new engine. That's all fantastic. So Is there? Is there? Does the truck do what you want it to do? Are you happy with the way it drives? Are you happy with the way it? It starts at idols as, or is there stuff that you don't like about it? Is there something you're trying to Like? Are you asking because there's an issue, or are you happy without runs?

Dustin:

I mean I'm happy. To an extent I'm. I'm curious, I know this, you're not like the tele-mechanic person, but it's. I Do think it's a little rich at idle and it's real smoky at like low rpm and Just getting out, just getting on it and I was really trying to see if I could get away from that. So I mean, I don't know, maybe that's I, but I did the three. I did the phase two, 300x, but I did the 1.0 ar, not the point eight.

Dusty:

Four what do you call low RPMs?

Dustin:

probably like 12, 15, probably 12 to 1400, just like before it drops a gear, kind of thing.

Dusty:

Yeah, I mean that that turbo is not going to do anything until, like you know, we're around 1900 or so, at least.

Dustin:

Yeah and that's what I was wondering, if the 80 to 84 by start.

Dusty:

It's not going to give you power at 12 to 1500. No, nothing, nothing you do will really, I mean, even from the factory, the stock turbo is not very responsive at 1500 rpm and any, certainly anything that's bigger than that is going to be even less responsive. So the only option there is, you know, either downshift, keep our PMs up and that you know that can be handled through tuning or gear ratio, tire size, combination of them. And you know, if you have a smoke problem, then either you've got an air issue, which we know there's not going to be a lot of airflow at that RPM. Maybe there's things you could do to help with that, like like check for leaks, pressurize the charger system, you know, verify that there's no exhaust leaks, you know, no, no charger leaks. And and then the other thing would be just reduce fuel and tuning. I mean, if it's, if it's smoking too much and everything else seems to be correct, then it would be a matter of pulling, you know, pulling fuel out of tuning, which is going to reduce power also. But that's just, it's inevitable. So as long as you're maintaining, you know, injection pressure, you're maintaining fuel pressure, you don't have any, any big leaks then. And Smoke is the issue with a lower RPM, you can drop the turbine housing size down and that will bring, if you drop from 1.0 to a point for housing, it'll drop your responsive RPM range about a hundred ish RPM. Hundred and fifty RPM maybe, but it's not. It's not going to give you power at you know, 12 to 1500. It's just not going to happen. And so if smoke is an issue there, it needs to be addressed through making sure there's no mechanical issues, no leaks, and then, if that's, if there isn't anything wrong there, then it's going to be Adjusting, tuning to clean the smoke up more than likely. And I guess the other thing would be like what's your tire size, gear ratio situation?

Dustin:

Running 35s right now. I mean I've got you asked about the rear end ratio or the transmission.

Dusty:

Yeah, well, the transmission doesn't change, but what's your rear end ratio?

Dustin:

Whatever factory on that one, I think it's probably 373.

Dusty:

The easiest way to check is we have a tool on our website. If you just go under the main menu, there's a the tools tab, the tools page, and you can punch in your Like pick, a pick, whatever speed and RPM you would be at with your tire size, and it'll tell you what, what the gear ratio is. Or you can go the opposite. You can put it a gear ratio and a tire size and a speed. It'll tell you no, any one of them, it'll go any direction, but That'll tell you for sure what it is per per KC.

Dustin:

The 205 30 is like the max injector for that phase two turbo. But now I was just curious if it's worth me stepping up to the stage three over the stage two and just being that way being in the middle of the road of the Turbo for the injector instead of being at the limit on my turbo now.

Dusty:

What do you think the benefit of going to the larger turbo would be?

Dustin:

I Physically don't know what the benefit or don't know I don't have a clue what to think the benefit would be. I'm just going off of like what they say on their website like, hey, these are the recommended injectors, the stage twos Mac injector you can use on their website, the 205 30. I was just thinking maybe if I run a turbo that I'm in all the road instead of a turbo that I'm maxed out on, would that give me a little bit more airflow. Maybe that's where I'm going with. It would make increase my airflow.

Dusty:

All right. So the best way I can answer that is this if you change In any way, if you put a larger turbo in the truck, it's going to be less responsive all the time. Every single time you go up in any size, whether that's a compressor wheel or a turbine wheel or a housing size, which, in the case of KC's chargers, if you go from a stage one to a stage two to a stage three, some piece of it gets bigger every time. That's the point is so that you have more airflow, but at the sacrifice of moving it up an RPM. So if you put a bigger turbo on it, it's going to have the opposite effect of what you want to do accomplish with a smaller turbine housing it's going to become less responsive. If what you're trying to address is cleaning up fuel or making less smoke after the turbo is spooled up, like at higher RPM, then that's when you would consider using a larger turbo. But if the issue you're having now is that it's not very responsive and it's smoky before you get on top of the turbo, that is not going to be addressed by putting a bigger turbo on it. That's going to be made worse by putting a bigger turbo on it. Like I said, like the exact opposite of why you would put a smaller turbine housing on it, Gotcha gotcha.

Dustin:

Yeah, see, that's where I was uncertain and definitely needed to buy with your expertise, that you could put a parts list or whatever to say yeah your name, kind of thing.

Dusty:

So, yeah, I definitely would not put a KC Stage 3 with those injectors, because all you do and this is the case anytime you want to make more power, especially on a non-VGT truck, non-modern variable vein exhaust system or exhaust housing anytime you want to make more power it requires a bigger turbo. And anytime you put a bigger turbo on it, the narrower your RPM or your power window's going to be and it will move it up to a higher RPM. So every bit more power you want to make that moves you up in turbo size will always move your RPM later just to make a higher peak number. And so that's why you know when we're targeting a build, that's and this is where most people land almost everyone is going to stay either with stock injectors and a turbo to match that, so it has the broadest RPM power window possible, or at most we go up to like what's the best balance of how much power we can make that's going to have that still maintains the broadest RPM band, and that's usually around a 30% nozzle and then like a KC Stage 1 turbo or something in that realm, like a 63, you know, 68 charger, and I shouldn't say like that, like specifically that that's a good combination and there's nothing like so there's nothing wrong with a 20530 and a KC Stage 2. That's a nice combination of parts, but it is less responsive than a smaller turbo would be.

Dustin:

Those injectors are too big to go back to a Stage 1.

Dusty:

They're not, because you can just not run a tool. You know you could just not run a 200 CC injector at 200 CCs. In other words, don't run it in a race tune. You know wide open throttle and it will not be 200 CCs. So you could move it down in turbo size. That still doesn't get you power at you know 12 to 1500 RPM. That's not going to be possible. But you can lower it some.

Dustin:

I mean definitely, I do understand that. Yeah, I'm not going to be. I mean I'm not producing power at that bottom end. I mean you never do. I mean your power comes at your top end. So I mean I get that part Now with the 20530, is there what advantage do I have to stepping up to the 20580 or 100? Just, I mean I kind of understand the numbers so I kind of don't.

Dusty:

It would make a higher peak power number and require a larger turbo, which would then move your power band up and Make it narrower. So rather than making power from you know 1900 to 3000 RPM, you would go from making you know, making power like 2200 to you know 3000 RPM To make a higher peak number at a higher RPM.

Dustin:

Which is not probably the best for towing. So bigger percentage size Means I mean not necessarily better like towing performance.

Dusty:

No, it's a common misconception that more that just simply making more power is needed to tow more, to tow better. Um, I mean, if in a perfect world that would be true, and that is sort of true with modern trucks that were actually designed to make, you know, 500 horsepower from the factory, which truthfully they rarely do. They have so many ways they derate they don't actually make that much power. But, um, if they did and it was practical and useful, like. But they also are way more efficient engines, way more efficient charger systems, turbos and Injection system. Everything about them is better. I mean, they're 20, you know 20, 25 year newer technology, significant difference. But when it comes to a seven, three, um, more power does not mean it will tow better and there's definitely, um, there's a lot of problems that come with trying to make more power that make it worse for towing because it's going to be less reliable, and so, uh, generally, this is you know, that we get asked a lot about, you know, I wanting to make your truck drive like a six, seven or like a modern truck in general. Um and uh, the best, like normally, what people are looking for is not necessarily a peak number that matches what a newer truck is You're looking for the, the drivability that comes from a modern, a modern diesel, and that's having a broad rpm band, um, like making torque at as low rpm as possible and they carrying that through. Um, that's more important than a peak number is. And, uh, the best way to do that is to keep it smaller. So I mean, your options here are kind of Uh, one one. If you do have three, seven, threes and you're running, you know, 35s, um, possibly regearing it, maybe making some changes to tuning If you make it 410. It depends on your tire size. Do you spend a lot of time on the highway Like? You spend a lot of time like 65, 70 miles an hour when you're towing, or are you usually slower than that?

Dustin:

Yeah, I mean most of it probably is. I mean I have definitely looked at regearing to 410s. I've looked at that, just haven't done it.

Dusty:

Yeah, might be 410s, might even be a lower gear than that, but what I would do is I would use the calculator we have on the site and whatever gear you want to tow, and whether that's overdrive or it's third gear, and whatever speed you want to be able to efficiently tow at. I would target between like 2,100 and 2,400 RPM. Like you would wanna be cruising when you're towing at that RPM.

Dustin:

And that's not hurting the motor at all, running at 2,300 RPM for a good period of time.

Dusty:

Oh, that's what it's made for.

Dustin:

I mean, I know, obviously I know you don't wanna keep the RPM low, but I didn't know like what the number is. That is not good to maintain for a long period of time.

Dusty:

Yeah, I mean you can run the engine at whatever RPM you need to Like. In other words, higher is not worse, and the engine is gonna be most efficient at around within about 200 RPM of 2,200 RPM, so between like 2,000 to 2,100 RPM and then up to like maybe 20, 24, 26, somewhere in that range, like that's. If you can stay in that window, that's perfect, that's where it should be and it's also going to be the most useful there. Even with a setup like this, you're gonna be right on top of the charger so you can roll into the pedal powers available. Stay clean, stay cool. That's what you're looking for and you know, in bigger tires we'll.

Dustin:

The out-offer gearing on your site. You all offer gear ratio stuff like that.

Dusty:

We don't have any gears listed. It's one of the projects we're gonna work on this winter is getting that stuff updated along with proper tooling to help, like, decide what to get and calculate it. But yeah, we can help you find it. But it's up to you to pick what you want. If your ultimate goal is that you want the best, the best towing rig you can have, probably one of the best things you can do is get rid of 35s too. Like I know that sucks if the truck's lifted. But like, bigger tires do absolutely nothing good for towing. It's all bad. They might look good and there might be some practical benefit if you're off-road or something like that. But smaller or stock-like tires are gonna be the best thing you can do for towing. If you don't want to change them and you'd rather just try to regear to somewhat compensate for it, that's fine too, but I would definitely regear. If you're running 373s and 35s right now, it's gonna be real hard to tow very heavy and keep it cool and stay in the power band.

Dustin:

Yeah, I mean, I've noticed, mom, even with the setup I got, my EGTs get pretty. I mean I'm pretty good at keeping them under 1200 or so, but if it right before it, if it don't downshift and it stays in overdrive, it gets up there pretty good. Low boost, low boost numbers.

Dusty:

And is that when you're? Is that if you're trying to cruise like below 2000 RPM?

Dustin:

Yeah, yeah, you'd like the 1800, 17, 1800, 1900,. You get real low boost numbers. Yeah, it gets real EGTs. Get a little warm.

Dusty:

Yeah, you just really can't tow below 2000 RPM. You gotta get RPMs up. That's what that engine's for and maybe that'll mean downshifting manually. You can just use the overdrive button and kill overdrive until you're going fast enough that you can put it back. But yeah, anytime you're towing you aren't gonna be able to make any sort of power below 2000 RPM and maintain it. Hey, if you guys like this show, share it with your friends. Share it with anybody you think would enjoy it. I really appreciate you guys listening. Check out the next episodes the 1023soul Shop Talk podcast, and you can find us at 1023soulcom If you're looking for parts. Thanks for listening.

Choosing the Right Turbo Size
Turbo Size and Performance Discussion
Optimizing Gear Ratio for Towing Efficiency