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CORVETTE TODAY #238 - An In-Depth Look At The C8 ZR1 LT7 Engine
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Jul 12, 2025
Jordan Lee and Dustin Gardner are the Chief Engineer and Assistant Chief Engineer of Small Block Engines for GM. They were on CORVETTE TODAY when the new C8 Z06 debuted with the LT6 engine. They are back on CORVETTE TODAY to talk about the all new LT7 engine for the C8 ZR1 ! Your CORVETTE TODAY host, Steve Garrett, leads you through the conversation with Jordan and Dustin. They get knee-deep into the in's and out's of the behemoth with 1,064 horsepower and 828 lb/ft of torque. Strap in and get ready to find out everything you'll ever want to know about the LT7 engine for the C8 ZR! on this episode of CORVETTE TODAY.
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And a shout out to Canadian Corvette Forum and Corvette Forum, welcoming Corvette enthusiasts from around the
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world. My guests on Corvette today appeared on show number 106 back in
3:50
April of 2022. These two men developed the record- setting LT6 engine for the
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C8 Z06. Jordan Lee, the global chief engineer of Small Black Engines for GM,
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and Dustin Gardner, the assistant chief engineer for Small Black Engines, are back on Corvette today to talk about
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their new masterpiece, the LT7 engine for the brand new C8 ZR1. Guys, welcome
4:14
back to Corvette Today. Thank you, Steve. I'm very excited to be back on your show. Dustin and I, there's
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nothing we like talking better than about Corvettes and Corvette engines. And the LT7 is really an exceptional
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piece as you saw when we did the reveal and the presentation at NCM a couple weeks ago. Yeah, echo that, Steve. Yeah, big
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thanks. Love being here. Like the LT6, the LT7, something we've been working on for a very long time. Very proud of. And
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it's always really fun for us when we can finally brag about it and have all the Corvette fans out there get all excited to get one of these in their
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garage. Absolutely. It's like you've got a secret that you've kept for six or seven years. You can't tell anybody. But now
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we can finally talk about it, right? Exactly. Yeah. Trevor keeps us on a really tight
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leash. Dustin's a lot better at it than I am. I must admit Dustin and actually the small blog team have a saying that
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if you want to keep a secret, don't tell Jordan. But I was able to keep this one. There you go. Well, guys, right off the
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bat, congratulations on this new LT7 engine. 1,64 horsepower and 828 pound-
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feet of torque. That's mindboggling. Did you guys ever think it would get that good?
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Whoa. Okay, so Dustin and I are going to answer that one probably independently, but we agree. We didn't set out at 1,64
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horsepower. We have a lot of experience with small block engines, a long history of push rod, two valve supercharged. We
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have a really good idea what those engines can make. When we do a new design, we're pretty close on what we expect to get power and torque-wise. But
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the LT6 and the LT7, they were new for us. We've never done such a high performance V8 engine before, a flat
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plane crank, and we were really pushing the envelope on what our analysis capability was. So, we did go for broke.
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And originally, our target was 850 horsepower. And the first engine we put on the dyno, it was loafing along with
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the wastegates open and it was already there at 850. We knew this thing was going to make a lot more than 850. So,
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it was a long journey to get to the actual number that we delivered. We didn't leave anything on the table.
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Dustin and the team scraped for every horsepower. We have a saying that there there's not a horsepower that we don't
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like. We've never met a horsepower we didn't like. So, we just kept pushing and pushing and pushing. And Dustin and
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the team and in particular the design system engineers you Lee and Chad Gilbert did a phenomenal job delivering
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tremendous power. Highest horsepower V8 engine ever put into a volume production car globally. Not just America,
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globally. It's incredible. Yeah. I comment on the surprise, right? It's hard to be a surprise when it's a long mountain climb to get there. But as
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Jordan says, the initial surprise was when we really understood that the system was more capable than we thought
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to start when we, you know, were achieving 850 out of the bag with a lot of iterations. It was an extended team
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folks. Jordan mentioned, you know, Jake and analysis and Julie West, a bunch of people in the calibration community. We
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started really sharpening our pencils and we made some significant hardware changes that point of view when we realized, you know, if we did X, Y, and
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Z, we can really swing for the fences on this engine. So, we slowly worked our way up in power. Ultimately achieved
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more than our wildest goal was to get to that four figure number. But yeah, it was a long mountain climb to get there, but truly shows the capability of that
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Gemini architecture. So, Steve, some really interesting backstory there. One of the most important days for us that's going to go
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down in our history. April 15th, 2024 was the day, and it was a long day that we ran the power certification testing
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in Pontiac. And it wasn't until late in the evening that the testing was completed. We all had hoped we'd hit
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1,000 horsepower. We had an internal target amongst ourselves of four digits. And then ideally, we'd want to get 1,026
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to be one horsepower more than the Dodge Demon 170. If you recall, they make 1,025 horsepower, but only on 85 fuel.
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And I think they even have a special cal for that. Yeah, we wanted this to be a nononsense pump gas more than,25. So Dustin, he was
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eyeing me instant messaging at our internal web through the evening along with the test engineers every step of
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the way as they were inching up on the power. Engine was brutal on the dyno. The dyno really struggled and that's why
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the test took so long because Dustin, what was it? A few seconds of testing and then we had to do a 10-minute idle
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cool off of the dyno. How did that go? Yeah. So, it kind of goes back to another fun story to put to this to not go too far down the rabbit hole. When we
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developed the LT5 for the previous generation ZR1, we were breaking dinos in the lab. So, the lab bought us three
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1000 horsepower dinos and said, "Okay, this will never be a problem again." Obviously, as we inched over that
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thousand horsepower point, we're like, "Shoot, now the dinos aren't big enough." But we got allowance to
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basically overpower the dinos for 30, 40 seconds at a time, and then we'd have to back off. So every data point we were
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running in the power runs, right, you have to go up, stabilize, get the data, finish it before the dyno lets go and
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then ramp down and let the dyno cool down. Wow. So what we thought was always going to be the biggest dyno we'd ever need, we as always in the small block
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fashion, we beat that. So it was hard on the dyno. The exhaust stacks had they were overtemping. We had to add water
9:00
injection to cool the exhaust stacks. I think the emission scrubbers for the cell were hitting their limits and the
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facilities people were coming by asking what the heck's going on. Wow. the alarms are going off. It was really quite a unique day for all the
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Corvette enthusiasts out there. April 15th, it will be the day in history, the 64 horsepower day. That'll be a date to remember for sure,
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guys. Now, this is the first time a Corvette has been turbocharged. These turbos are huge at 67 mm. Talk about how
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well they work with this engine. You're talking about the turbine. The compressor is even bigger, 76 mm for the
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compressor and the turb. But, maybe give a little background on how we select those turbos and Elliot, why they're so
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big. Yeah. So what they are is the compressor side is 76 mm, the turbine side is 67.
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That's to get a better balance with, you know, response on the turbine side and then the flow and compressor throughput
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that we need on the turbine side of it. So the hot side of it, the turbine side, it's actually an integrated manny turbo
9:56
housing. So the turbine itself is part of the exhaust manifold and it's a custom piece designed for the LT7 in our
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packaging environment. So, what that gives you is that turbine wheel is really close to the exhaust valves and
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the runners in the head and the way it directs the air into that turbine housing are definitely optimized for our
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engine and our vehicle configuration which really helps with fast spool up times because you only got a couple
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inches for that exhaust flow to travel to that turbo. Then on the 76 millimeter compressor side, it's a very large
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monoscroll turbo. What model scrolls give you is very good high engine speed read that is high flow boost capability
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because when we knew we were really going to be swinging for this thousand horsepower number we needed a turbo that was going to give us everything we
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needed at the top end now to help mitigate some of the downsides of big monoscrow turbos is it has a ported
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inlet shroud that helps with the low turbo speed aerodynamics which lets a big turbo behave much better at lower
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engine speeds. So, that's a big part of helping pull that peak of the torque curve down to where we get over 800
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foot-lbs of torque by 3,000 RPM. So, we still have good low engine speed response without sacrificing the top
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end. And then the other big enablers in the turbocharger assembly to help with turbo lag and response and dynamic
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driving is we have electric wastegate actuators as well as electric pressure relief valves. So, with that, the
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control guys do a bunch of trick stuff and dynamic driving conditions to keep the turbo speed up even when you're off
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throttle. to virtually eliminate turbo lag. So, it really works well as an integrated system. Definitely bespoke
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for the LT7. It's also worth mentioning, Steve. It's a really large turbo. When we originally went out for sourcing, a lot of the
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turbo suppliers that we've used on other GM engines wouldn't even quote it. They didn't have anything that was that big
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of a frame size. Wow. So, shout out to Borg Warner who worked with us developing this this really
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large turbo. Thank you, Bor Warner, for sure. And we'll talk about turbo lag in just a second, guys. Also, head castings have
11:52
unique ports and larger combustion chambers, too. Yeah, like so many things on the LT7, I
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know I've said this again and again, it is not an LT6 with turbos on it. We've touched virtually every component in
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that engine to optimize it around this boosted setup. So, it is a completely unique casting and that casting is there
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because of, as you said, the combustion chambers are unique. They're much larger than the LT6s. They're still 100% CNC
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machined like the LT6s. So, the new cylinder heads look like jewelry. And then very unique exhaust ports where an
12:23
LT6 will have the exhaust flow very evenly spaced and the exhaust ports in the head actually start turning the
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exhaust flow up into the LT6's tubular headers. We're doing the exact opposite with the LT7. We're trying to turn that
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air flow or exhaust flow down and together to point it right at that turbine wheel. So even the outside
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cylinders exhaust ports actually angle inward and down. Once again, trying to bring all that flow together in a very
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short distance directed right at the turbine wheel. So, Steve, a big takeaway for you is that the LT7 was engineered to be a very
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optimized turbo engine. Absolutely. Dustin keeps mentioning it. It's not an LT6, even though they share basic
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configuration and architecture for the big parts like the block and the crank, the crank train. All the other things
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that were optimized for turbo operation was done for LT7. That's awesome. Guys, let's talk about the intake system as well because I know
13:11
that was tuned for those twin turbos, wasn't it? Oh, yeah. As you guys know, the LT6 has
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a very large intake manifold, and that's done to get all the naturally aspirated, high engine speed tuning that gives that
13:23
engine the power and efficiency it has. We're looking to do the exact opposite with the LT7. The intake manifold is
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isolated left to right, and the intake volume is about 60% less than the LT6
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cuz you want a lot less air to compress. Once again, helping with turbo lag, just getting into base engine design there.
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So, the goals of the manifold are very different and that's why they look so different. The other thing is that intake manifold also packages a
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secondary fuel system as well, which I think you plan to talk about in depth a little bit later as well, right? Right. Yeah, definitely. All right,
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guys. Let's talk about turbo lag because that's always been the knock on turbos. You've created this engine with minimal
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or no turbo lag whatsoever. How did you guys overcome turbo lag? So to break
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that down into kind of the three different areas you can have it, right? So from a standstill, you always have to
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accelerate the turbo. That's just base physics. So you minimize that with all the things we did with the base engine
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design. Back to what I was talking about before, that turbine wheel is really close to the exhaust valve with that
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bespoke integrated Manny turbo design that we have. So you get the exhaust gas to the turbine wheel very fast and
14:28
that's going through a ball bearing center housing on the turbo. So what that does is it greatly reduces the
14:34
friction on that turbo wheel. So any of the energy going into the turbine wheel is going to accelerating. You're not
14:39
losing it to friction. Nice. That helps there as well. Then in addition to that, kind of what I was talking about with the very small intake
14:45
manifold air volume. That kind of goes into further the two charge air coolers that are on the engine. Those charge air
14:52
coolers sit right on the cam covers. So the path from the compressor wheel to the charge air cooler is only a few
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inches and it's only a few inches from the outlet of the charge air cooler to the throttle buys the intake. So you
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have very little air to compress and everything is very tighten on the engine as you see on other integrated turbo
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packages. Right? If you have the turbochargers that are further from the engine or remote mounted intercoolers,
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that's just more air you have to compress which slows down your boost response time. And then off of a start
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where we do dynamically what we call dynamic boost control. So, like in a call it track driving condition, we all
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know the C8's chassis controls know when you're in a driving state like that, you go into a braking zone and you tip off
15:32
the accelerator pedal, you're decelerating, you know, turning, you're still carrying engine speed, but given
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the electric waste gates and the pressure control valves, we can actually close the waste gates under del and
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braking and keep that turbine speed up and we'll go into a closed loop boost control and we'll hold boost at the back
15:49
of the throttle body. So when you come out of that braking event and you roll into the throttle, the turbo is already
15:55
at speed and you already have boost at the throttle body. So it very much behaves like a naturally aspirated engine in those dynamic track driving
16:02
conditions. Man, that's amazing. You guys, Steve, it's worth noting the controls engineers have done a remarkable job
16:08
coming up with software that does the dynamic boost control and the anti-lag software. I do recall when the the car
16:14
development began, a lot of the performance drivers were complaining it's hard to drive the car fast because the turbo lag is so horrendous to get
16:21
around corners. It was unpredictable. Yeah. And then the controls engineer said, "No, just wait. We're going to enable the new software and the boost control."
16:28
And it was like a miracle. I mean, everybody who's driven the car, even Tony Roma, he's the new chief that took over for Taj when Taj retired, he didn't
16:35
have a lot of experience with the car. And when he first drove it, he was just astounded that it felt just like a
16:40
naturally aspirated car. I think I need to drive it too guys just to experience that and give you my honest opinion.
16:46
Don't you think? I think you do. Yeah. Trevor will help you out. That's an awesome deal. That would be
16:52
fantastic. Now, with these turbos and all the technology in it, they do have to be cooled in oil, too, don't they?
16:59
No, absolutely. So, both turbos do have dedicated coolant feeds. So, that kind of goes around the outside path on the
17:06
inside of that center bearing housing to keep that bearing housing cool. Then we also have dedicated oiling lines for the
17:11
same thing to keep that ball bearing even though it does have a ball bearing in it for the main shaft bearing interface that is bathed in oil that we
17:18
do feed and then actively scavenge away from the engine. The other part to the integrated exhaust manifold that we told
17:24
you about to keep the turbos close to the engine ends up mounting them very low to the engine. So with that oiling
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we actually have to actively scavenge the oil away from the turbos. And in the
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LT7, we have a seventh dry stump oiling stage that's completely dedicated to
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pulling oil back away from the turbos. So you never have any oil stacked up there. That's pretty fascinating.
17:46
I think I mentioned it during my presentation at NCM. That seven stage was visible. None of the journalists caught that on the LT6. It was there and
17:53
we kept talking about a six-stage pump. Yeah. Hiding in plain sight, wasn't it, guys? That's funny.
17:58
I can't overstate the engineering work that Dustin and his crew did on that loop system. uh loop system is the heart
18:05
of the engine. The turbocharger is included, but also the engine performance, its ability to go around tracks extremely fast without any
18:12
lubrication system issues. Pretty remarkable. Yeah. Well, guys, let's take our first break. When we come back, we'll talk
18:17
more about the new LT7 engine for the ZR1. Coming up next here on Corvette
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just give them a call 833-6394231. I'm your host Steve Garrett. With me is
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Jordan Lee, the global chief engineer of small block engines for General Motors and Dustin Gardner, the assistant chief
22:14
engineer for small block engines. We are talking about the already legendary LT7 engine for the upcoming C8 ZR1. Guys,
22:22
this car is dual injected. There's direct injection as well as port injection. That seems fascinating to me.
22:29
Tell me more about that. Yeah, Steve. Well, it's there for necessity and other functions. As the
22:34
team out there knows, we did do something similar to this with the LT5 in the previous generation ZR1. We did
22:41
it there only because we needed the added fuel at the top end where the LT7 like the LT5 definitely needs the added
22:48
fuel flow. and start out with a fun fact there. If you can park an LT7 at peak
22:54
power, it'll consume almost two gallons of fuel a minute. Wow. So, if you think about what you need injector wise to be able to basically
23:01
feed it what it needs to make that level of power is quite astonishing. The added eight PFI injectors on top of the eight
23:08
DI injectors, which are still exhaust side DI like the LT6, are definitely all used at the top end. What is really
23:14
different and better utilized with the LT7 is we blend those two fuel systems throughout the operating range even like
23:22
after catalyst light off when the engine is idling we'll completely shut down the direct injection system that's got a
23:29
couple good advantages to it one it's much quieter at idle to do that and two
23:34
it helps with emissions to blend in some PFI and the light load operating range and we do that for quite a bit of
23:40
driving where you'll drive on PFI only till we start blending in the DI with load. So, it has a lot of NVH emissions
23:47
as well as peak power benefits to it. So, it's it's a great tool to have in the toolbox with this engine. Yeah, definitely.
23:53
Steve, just another tidbit just as Dustin mentioned that the fuel flow of two gallons per minute of peak power or
23:59
those who know Corvettes typically have 18 gallon fuel tanks. So, it'll drain the tank in 9 minutes. Wow.
24:04
So, it's very thirsty. for background for you. You know why the two fuel systems like Dustin mentioned, it offers
24:11
a lot of advantages, but if you if we tried to do that with one injector, the injector would have to be so large to
24:17
power 1,64 horsepower that the low-speed light load fuel injection capability
24:22
would be heavily diminished. We wouldn't get the fine control that we wanted for idling and low speed drive quality. So,
24:28
the two fuel systems was a necessity. I get it. I understand that now. And guys, you did keep the flat plane crank
24:34
as well. talk about how that's better for the LT7 engine rather than the crossplane crank.
24:39
Well, Dustin and I are going to talk about this one. There's a lot of misconceptions about flat plane cranks.
24:44
The crossplane crank engines also can make a lot of power and they also have a little less vibration. The beauty of the
24:50
flat plane crank though and the configuration that we've chosen for the LT7 with a really short stroke and 80 mm
24:56
stroke is that it revs voraciously. So even a neutral rev from an idle for an LT6 or even an LT7, it'll tag out to
25:03
8,000 RPM extremely fast. And a lot of that's achieved by lightweight connecting rod, optimized piston mass,
25:08
and a very short stroke at the crankshaft. The beauty of a flat plane though is it does help you improve
25:13
volumetric efficiency. You don't have cross talk with two cylinders that are doing an intake stroke one after another
25:20
on the same side of the engine, the same plenum. So it's effectively two four-cylinder engines and it breathes bankto bank. So
25:27
you are able to achieve higher volumetric efficiency and more power. Wow. So that's the main benefit.
25:32
Dustin, what are some other intrinsics that you've mentioned the flat plane crank has advantages over? You kind of already touched on the big
25:38
ones, right? I mean, we definitely didn't want to give up that what I always call revappy nature. That's part
25:43
of just the DNA of the Gemini engine twins, right? Without that, we would really take a lot of the character that
25:48
makes these engines fantastic and very emotional and visceral engines to drive. So maintaining that was absolutely
25:55
needed there. But as you said, say to Jordan, the breathing part of it is huge, especially when we're trying to flow these turbos at their upper air
26:01
flow limit. Having that balanced air flow bankto bank really takes out a lot of other dynamics that you have to fight
26:08
to balance that out. When you have two intake events on the same bank back to back, you really change the way things
26:15
flow. And we'd have to integrate the two banks together and we wouldn't be able to do what the split intake enables us.
26:22
We control the turbos as two independent four-cylinders. Another thing that I I should have mentioned when we were
26:27
talking about the turbos in the past, we actually have turbo speed sensors in both turbos. So, normally you have to
26:33
leave a little bit of margin to your max turbo speed when you're predicting it, but we actively measure it. So, between
26:40
the two banks, we can run the turbos right up to the red line because we're know where they're at. And because we
26:45
can operate them independent of each other due to that firing order and intake allows us to do that, which is huge. See, for your understanding and
26:52
for the understanding of your fans that are very technically savvy, the turbo speed Dustin's talking about 137,000
26:58
RPM. So, it's getting up there to maximize the boost is really important. But while a flat plane crank engine can
27:03
be very revappy, that's primarily due to the short stroke. So, I don't want to give you the misconception that if you
27:08
did a crossplane crank, it's very short stroke, it could also be quite revappy. Got it. So LT6 flat plane LT7 with the
27:16
turbos as Dustin was explaining is to be very complicated if you do a crossplane to get the right balance and the tuning
27:22
and ideally you want every cylinder to breathe the same amount of air and produce the same amount of power. Yeah, turbocharging a crossplane crime V8 that
27:29
becomes extremely difficult. H interesting guys and the mindboggling thing about this engine is that it's got
27:36
more power than two LS7 engines. That's more power than two C6 Z06s. And that
27:42
engine, the LS7, was a seven liter engine. This is five and a half lers. Wow.
27:48
Yeah, Steve, I like to joke that with the LT7, you get 14 lers of Gen 4 fury.
27:54
Oh god, it's a good way to look at it. That's awesome, guys. I like that. I have to remember that
28:00
one. Also, the transmission's been fortified to handle all that power, too, hasn't it? Yeah. As far as the details, I know
28:07
talking to my transmission counterparts, they did strengthen the shafts and the gears. I think are a little bit wider.
28:13
All the ratios are the same, but the transmission had to be hardened. Does you know any other details on what was hardened in the transmission?
28:19
Yeah, not to get too far out of my swim lane, but you touched on most of them. Ratios are the same, case is the same,
28:24
but all the key internals that needed to be beefed up, for lack of a better way to describe it, were to handle the
28:29
torque. It is a unique transmission to the ZR1 to handle the LT7's capabilities.
28:35
Yeah, I think so. With all that power, for sure. Also, guys, we have extra venting on the outside. talk real
28:41
quickly about the vent in the wishbone and then the vent on the top rear quarters which kind of reminds me of
28:46
that vent on the shoulder of the C7 Corvette. Yeah, I guess the easy one is to talk about the split window or the spine on
28:53
the coups and and that's kind of exactly what it looks like, right? That's just additional engine compartment chimney
28:59
venting. So, you know, up high heat extracts that way in addition to the great styling throwback and how cool it
29:04
looks. The interesting ones, as you brought up, Steve, are the ones kind of on the rear quarters. Yes. So, in
29:10
referencing those to the previous generation where those were there for brake cooling on the ZR1, the additional
29:16
rear brake cooling are the ones in the wishbones, which are interesting, but those are dedicated to the rear brakes.
29:21
The ones that are up on top of the hatch at the quarter, those are actually additional air inlets into the fresh air
29:28
air induction system to feed the engine. Okay? On all current generation Corvettes, right, we bring in the engine air
29:34
through the inlets behind the doors by the rear radiators. The coupe ZR1s do that, but in addition to that, they
29:40
bring in additional fresh air up on top of that quarter panel. And the vehicle guys did that because there's actually a
29:45
good high pressure cool air zone right there. So, it doesn't give the engine inherently more air. It gives it access
29:52
to cooler air. Oh, that gives you more time before you get into any thermal sort of derate on track
29:58
with the coups there. So, we were just trying to give them the best opportunity to grab the coolest air around the car is what those are doing.
30:04
That makes sense. And you know what I like the best, guys, is right on the driver information center there on the
30:09
dash, you have a turbo boost meter. That's so cool. Yeah. You have a turbo car, you want to
30:14
be able to see that you're making boost. And I would say in addition to that, driving the car, you're never going to second guess that there's turbos there.
30:20
When you get into boost, you can hear it and you know it. And you can feel it too, can't you? Yeah. So, Justin and I, we both drove
30:27
ZR1s for a while, for a week each. You don't have time look at the boost gauge. It's there. But uh when you you match
30:33
the throttle, you're preoccupied with a lot of other things. You're just trying to harness the car, aren't you?
30:38
That's awesome. Your ears are a very good boost gauge in it. You know, when you're making big boost, you can hear it and you can feel
30:44
it. I can imagine. Well, guys, let's take our final break. When we come back, we'll talk more about the LTH7 engine
30:50
for the C8 ZR1. Coming up next on Corvette today.
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And now back to the only current podcast on Corvettes, Corvette Today with your host, Steve Garrett.
33:29
Thanks again for listening and watching Corvette Today, the show that talks about everything Corvette. Corvette
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I'm your host Steve Garrett. With me are my buddies Jordan Lee, the global chief engineer for small block engines for
34:04
General Motors, and also Dustin Gardner, the assistant chief engineer for small block engines. We are talking about the
34:10
already legendary LT7 engine for the upcoming C8 ZR1. Guys, the cool thing
34:16
about this engine is that it's still built at the performance build center there at the Bowling Green assembly
34:21
plant. How long does it take to build an LT7 engine? Well, I guess Steve to first jump in there about the performance
34:27
build center. I can't rave about that place and the folks that work there enough. They are the reason we can do
34:32
engines like the LT6 and 7. Given where we traditionally build engines in general and definitely small blocks,
34:38
there's a lot of manufacturing constraints given the higher volume that those plants run and having a individual
34:44
with an engine build cart handbuies the engineering hands to do a complex
34:50
engine like this. So yeah, that team there and their passion around it and precision is huge and only reason we can
34:55
even talk about engines like this. That being said, to get back at your question, so the LT7s will be built by
35:01
the same individuals and the same line as the LT6s. They'll be built together. Obviously, there's a little bit more
35:07
content to an LT7, but ideally a builder should be able to build an engine in about 4 hours.
35:13
Wow. So ideally build two engines a shift is the goal. See, if you have not been through the build center at Bowling
35:19
Green, you must go. You'll meet some of the finest craftsman putting engines together that you've ever met. They're
35:24
so skilled at what they do. They're perfectionists. They take great pride in every single engine they put together.
35:29
And I think they put their own name. They have a badge. It's attached to the engine with their name on it. And I remember it was quite some time ago, I
35:36
bought a C7 Z06 and I met the engine builder who's now kind of a friend of mine. His name is Jason Neil. He told
35:43
me, I asked him, "Why did you get into this and you take such great care? You're such a perfectionist. Every little detail I've been watching how you
35:48
put this together." That's cool. And he said, "I'm going to buy one of these cars one day, Jordan, and it may
35:54
have my name on it, so I'm going to build every one of them." Like, I'm going to buy it. That's awesome. That's a great idea. And
35:59
you know, guys, that performance build center, I've seen from a distance, you still can't get back in there and you
36:04
can't build your own engine. But hopefully one day they will reopen that option for Corvette buyers where you can
36:10
go in with the engine builder themselves and build that engine that is going to go in your car. Even though this engine
36:16
is a quote unquote small block, it's a huge engine. How did you fit that engine into a C8?
36:21
I'll start by saying that there was a good reason why we never put double over cam engines in front engine Corvettes
36:28
cuz they just don't fit. Yeah, they are big and the mid-enine car allowed us a lot more engine
36:34
compartment. we could get wider and we could get taller. So that pretty much took the gloves off on the architecture
36:39
we wanted to choose to get the most power possible. Steve, before Dustin talks, I think you have seen the rolling
36:45
chassis. Yes. That was at the Corvette Museum. If you took the time to look carefully, that engine is stuffed in every nook and
36:52
cranny in that engine compartment, every line, every wire, every hose. Yes. Dustin and his team did just a
36:58
remarkable job in packaging, which ironically is one of the most difficult things to do in designing new engines is
37:03
integrating and packaging them in the vehicle. Yeah. Yeah. To jump in there at the beginning of it, right? It's the vehicle architecture of the midenine is really
37:11
what enabled us to do that. You get the question, you know, why turbo over supercharging, right? And the
37:16
supercharging was the right answer for the previous generation front engine car given the compact nature. And as you've
37:22
seen it, Steve, the width of the LT7 in the ZR1 is so wide. Imagine trying to
37:27
put that between wheels and then wheels that need to turn, right? So, the architecture was a big enabler.
37:32
And to make this level of power, you really need the efficiency of turbocharging over the supercharging
37:38
solution, which as I said was right for the previous generation, but this generation allowed us to do that there. And as Taj and company have alluded to
37:44
in the other reviews, we knew the plan from the beginning for the architecture of the car. And when you look at where
37:50
the turbos are kind of packaged in those little triangle wedges behind the rear radiators and in front of the rear
37:56
wheels. Yeah. That space was always there for the LT7 when we first did the Z06 body style.
38:02
Yeah. So I want to say we could do it cuz we packaged it from the beginning, but also they could never give us all the space
38:08
we wanted. So it was definitely a shoehorn exercise. We optimized every millimeter we needed. We moved stuff on
38:14
the vehicle and on the engine side where we needed to and where we could to enable it. But it was definitely a one team effort between the vehicle team and
38:20
the engine team to make this all work. As I said before, with the LT7 being the plan from the beginning, we knew what
38:26
this engine looked like many, many years ago. So, packaging work started a long time ago. And you know, that was a question I was
38:32
going to ask you guys. I know that when you were on Corvette today with me talking about the LT6 for the Z06, it
38:38
took you 7 years to develop that engine. And these engines were developed basically side by side. They're the
38:43
Gemini twins. How long did it take to develop and finish the LT7 if the LT6 took about six or seven years?
38:50
As you said, Steve, they started at the exact same time. So, we got what, two more years into the LT7s than we do the
38:56
LT6s. That being said, we architected the engines and kind of laid everything out together at the same point in time,
39:02
but obviously the engineering work and focus would have been more LT6 forward at the beginning. The architectures and
39:08
everything were defined at the same time. That offer up too, Steve. It's a long time. I looked at some of my history
39:14
files to identify when we actually started working on these engines and it dates all the way back to 2010.
39:20
Wow. So, we're doing analysis and packaging and concepts. We didn't get really
39:26
serious until 2014. Okay. But, yeah, it's been a long, long time coming.
39:31
It's amazing how far in advance you guys plan out and start working on things like this. It's simply amazing to me.
39:39
And also, interestingly enough, guys, the ZR1's not going overseas. I know that the center exhaust stays because of
39:45
not going across the pond. It's a shame people over there won't be able to experience 1,64 horsepower.
39:52
Well, we're not ready to state what our future plans are. We're very focused on North America now cuz that's where the
39:58
reveal was in the launch, right? But never say never. You know, things can change and we haven't revealed any plans yet. And actually, I'm not even
40:04
privy to what the plans are, but there's a lot of discussions on what we're going to do with our cars. Yeah. And I know the Corvette team said that the ZR1 is going to go over
40:10
probably 215 miles an hour. I know testing isn't finished yet. What are you
40:15
guys guessing top speed on this car is going to be? Well, I think we're going to eclipse 215 by a pretty nice margin. I wouldn't
40:22
think it's going to be a couple of tents or a couple miles per hour. You look at a 1000 horsepower versus what the C7
40:28
did. I think the C7 was 214 755 horsepower. Yeah,
40:33
it should be pretty good. Trevor swore us to secrecy. Dustin and I already know the number, but we can't tell you.
40:38
Okay. Well, that's fair. It's all right. I know testing is still going on. I can tell you though, you're going to be very impressed.
40:44
I'm already impressed, guys. Just impressing me more is just icing on the cake.
40:49
Jordan, Dustin, thank you again for taking the time to be back on Corvette today. When we get a new engine, you
40:56
guys are coming back on the show. How's that sound? Sounds great. Anytime, Steve. Anytime you want to talk to us, more than happy
41:01
to do so. This is always a blast, Steve. You know us and you and your fans. If we can talk about engines with the Corvette fans,
41:07
we're always down to do that. We can do this all day. Guys, you have an open invitation into Corvette today anytime you want. Let me
41:14
know when that new engine is coming down the pike. Thanks again for listening and watching Corvette today. And be sure to
41:19
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