General Motors is dusting off a very familiar engine code in the near future. First posted to Reddit, internal GM documents have revealed the LT5 V8 engine is returning, and it’s coming for the 2018 model year.
Specifically, it will be a 6.2-liter LT5 DOHC V8 engine, as coded in a table in the document of “Passenger Car Engines For GMNA.” At the very end of the table, there it sits: “ENGINE GAS CYL, 6.2L, SIDI, DOHC, VVT, ALUM, GM,” with the book code “Y”. In GM speak, that means it will be exclusively used in the 2018 Corvette.
There has only been one other DOHC V8 engine in the Corvette’s history, and it was the C4 Corvette ZR-1. It’s quite likely the Corvette team and General Motors will reintroduce a modern LT5 V8 engine when the 2018 C7 Corvette ZR1 decides it’s ready to show face.
Furthermore, the 6.2-liter LT1 V8 and 6.2-liter LT4 supercharged V8 engine are both still listed in the 2018 engine document. From that, we can gather the LT5 V8 will not replace either of those engines, but instead be reserved for something new altogether.
However, the table makes no mention of forced induction.
If the 2018 C7 Corvette ZR1 is going to be the most powerful Corvette we’ve seen, it will have to outdo the 650 hp produced from the 6.2-liter LT4 supercharged V8 engine. It’s hard to imagine GM working some wizardry to surpass 650 hp without superchargers or turbos.
If we move past the Corvette ZR1, the next logical option would be the all-but-confirmed mid-engine Corvette. Of course, all we can do is speculate on such a car, but a 6.2-liter LT5 V8 engine seems like a good starting point for what could be a revolutionary Corvette.
We don’t know where exactly this reborn LT5 V8 engine will end up, but it’s coming to a Corvette near you very, very soon.
Comments
Wow ,That is some great news ! I am looking forward to seeing all the details of the new Chevy 6.2 DOHC engine .
Which on the exact pdf it also confirms the LaCrosse will be the first recipient of the Avenir treatment. But honestly not sure where it says there will be also a 1.6 engine for the chevrolet sonic
Using the LGX 3.6L DOHC-4v V6 as a starting point and making over 93 horsepower per liter of displacement, the new LT5 6.2L DOHC-4v V8 could possibly make 576 hp @ 6800 rpm.
600+ N/A or nothing, they can easily do this.
My money is on the ME ‘Vette being twin turboed. Should be easy to see 700.
Un named reports had them testing over 1,000 HP but they would only use as much as they can put down.
Anyone wanting to challenge that just look to the tuner cars already making that.
Isn’t it possible that a more track focussed fixed roof, lighter, higher faster revving N/A engine vette could get the ZR1 name. To me I’ve always felt that the c7z was more an evolution of the c6zr1. This would honor the c4zr1 dual overhead cam as well as honor the original zr1 optioned race ready 70s zr1 cars.
I’m hoping these dohc Chevys are short-lived. When the C4 Grandsport replaced the ZR1, it seemed more raw, and much cooler.
I’d rather they bring back the 7.0L. Go to solid lifters if they have to. Buy the concentric cam from FCA, I heard they need the cash. I’m serious. Heck, I’d rather see an AL block 572 or centrifugal-SC 6.2L.
The C6 Z06 is the high water mark for me. I haven’t decided how I feel about upcoming mid-engines.
You want bias ply white walls too?
You do not want solid lifters or anything from FCA.
Trust me!
What are solid lifters and what are their problems? Scott3 and others here are well trained engineers and I learn many good things, thanks. I think solid lifters are valve types? If they are too heavy, do they cause more damage from reciprocation stress? Thanks again.
Lifters go in between the camshaft and the pushrod. They are not valves but they activate the valves. Solid lifters also known as mechanical lifter. Are lighter than hydraulic lifters. So the engine can rev higher. However they require periodic adjustment. That would be part of the emissions system. Which is required to go for 100,000 miles if it needs any maintenance that would have to be covered by the manufacture. that would cost a lot of money if everyone had to bring the car into a dealer for a free valve adjustment.
Also with roller lifters today you still get the rpm but can remain hydraulic.
Solids are a pain and will wipe the can out if not adjusted
Thanks!!!
Gearhead1 and Scott3, cheers!
I agree. The two problems with the Z06 are TOO much torque, making the car a monster to control coming out of corners, and insufficient charge cooling which saps the performance in the heat. a NA DOHC V-8 solves both of these problems – HP without excessive torque, and no supercharger to cool. Mercury Racing from Mercury Marine is routinely getting 700+ HP out of 6.2 and 7.0L GM blocks with their DOHC heads for offshore boats, so this is very possible. If this is what they are doing for the ZR1, they are building a real winner. IMHO.
There is no EPA efficiency rules on boats that I know of, thou there is this.
http://gmauthority.com/blog/2017/04/2018-c7-corvette-zr1-gas-guzzler-tax-spotted-in-gm-order-system/
Hmm, I could be wrong but I believe the “Y” code was once on the LS7 too. Ultimately, it made for one heck of a motor in the Z/28. Here’s to hoping for more than one use in the future.
You are thinking about what I have been considering.
I originally did not expect this engine this soon but it opens the door to many things.
You just opened the gates of my mind bro. Imagine a 427 DOHC motor. Oh man. I’m excited.
This all sounds great, but how much more power can they put in the current Corvette? Auto critics have already said that the current Z06 is pushing the limits of putting the power to the ground. How much is too much before the need to go to mid engine or AWD?
The current car can use around 750 HP with full down force.
The next car should lift that level and it is not that far out. 2019?
The other demon here is they will have to go DOHC just for the emissions as they will increase in regulation and the extra valves provide timing that will improve the emissions while not hurting power.
Down force has no effect to little effect on initial acceleration. The C7 is getting beat in acceleration by its competitors in 0-60_ 0-100_ and 1/4 mile due to traction issues. A rear-mid-engine will help traction, but at a certain torque level whether front or rear mid-engine, AWD will have to be employed.
No but it does on lap times and braking. The Corvette is about more than quarter mild times.
It is now almost into the 10’s so that was not an issue.
Yes! Obviously, down force comes into play on the track, but most Corvette buyers are looking at the metrics of acceleration. And most are not Randy Probst and will never put their Corvette on a road course, so the Vette’s acceleration times are a factor to them.
Down force mostly comes into play on the track in braking(as you implied), and keeping the car dynamics(lift) under control in the high speed sections of the track. It has little to do with accelerating out of the slower corners.
Too much down force can slow lap times.
The origination of this discussion was about high horsepower and traction, getting that power to the ground in a usable form.
yes! Obviously
Tre get real!
If we were talking about a car that was 15 sec in the 1/4 and 0-60 in 6 seconds that would be an issue.
But we are speaking about a car that is in the 11 second range in the 1/4 and 0-60 in 3 seconds with a front engine set up.
The vette team has made it clear the C7 is limited to around 750 HP and has been wanting the mid engine even when planning the C7 according to Lutz that had to tell them no.
As for down force they have been spending much time to get it right, not only that but to make it adjustable.
Down force is good for lowering lap times but it also kills mpg that adds to the guzzler tax.
For the money paid there are few choices that give you the handling and power the vette does.
The vette team is not able to do all things. The still have limits in price and what hardware they get. Case in point the C7 was not mid engine and to center the weight they only could lengthen the wheel base.
They still have to make a business case.
The net
The next step is coming and there will be changes. Regulations are in part for some but the reality of cars from Audi and Mclaren getting cheaper and making some really good cars. The new Mclaren is under $200K.
The end result is we will still get a great car and much more performance per dollar.
To win they must deliver more for less as that has always a Corvette halmark and what many always look for. We will continue to see this in the C8.
One other thing is could the block here also under pin a Cadillac DOHC engine as they are working on?
Why doesn’t GM revive the Northstar for the Corvette and a sports Cadillac model?
Nowadays it seems the Chevy guys are jealous of the attention Ford got for the GT350 flat plane crank.
It really just shows Cadillac missed the mark for their smaller performance cars XLR and ATS-V. A 10,000 rpm dohc V8 fpc would’ve impressed people. Screaming RPM would give Caddy distinctive character.
They also would have to be happy with <1000/month XLR sales, if it existed today.
Matt I really don’t many GM folk wishing for a flat crank and more RPM.
More power but not so much RPM.
The XLR missed the mark because the Corvette was the same car only faster for less.
The ATS is more up staged by the CTSV.
I don’t think the Chevy guys are jealous of anything having to do with the Mustang or the flat cranked lump they are putting out there. Ford swung for the fences with the GT350R and it could barely get ahead of the Gen5 Z/28 with the heavy old Zeta platform with that sweet and beautiful sounding LS7 powering it along. So no the Chevy guys are not jealous. ZL1 will likely handle the GT350R as the 1LE isn’t that far off of it and the next Z will probably annihilate it. Sounds to me like the Ford guys might be jealous of the fact GM is keeping the larger displacement and going DOHC while Ford is downsizing and always one step behind in performance. All the flat plane did for the Mustang was give it a different sound and the ability to rev. What it will lead to is extra vibration and long term reliability issues.
It’s funny how you chevy guys would dog on ford for going to be dohc years ago. But now your pristine car will be doing the same thing. The gt350r is faster then The 5gen z28 and if ford put carbon ceramic brakes on the 350r like g m did with that z28 it would be laughable on how bad it would destroy it. Have fun with those 8000 dollar brakes changes on that z28. So who does more with less. Im saying the mustang is the better enginered car .The new 1le isn’t even close to The gt350r on a track. Just check the lighting lap results, 3 seconds is an eternity on a track. And the zl1 will beat the gt350r,but when the new gt500 comes out the camaros time on top will be 1 yr. Gm has some nice products, but sorry the fords our just better.
The Nstar was an engine they never really got right.
Low tension rings that would carbon up and use oil. Head gasket issues. Engine mount issues and more. It was an engine done on the cheap as GM was going broke.
A new engine done today with a much better funded GM would be so much better.
Northstar? Those were junk! They need to stay away from that name.
I was thinking the Block would be the same as LT1 LT4. Except for the camshaft drive. New cylinder heads intake manifold and exhaust manifold. And new Pistons to match the combustion chamber. So maybe a year after the engine goes into production there will be a kit to bolt on these new heads to an LT1in the 2019 performance parts catalog. Plus a crate engine.
If they did, it may not be a simple bolt on. DOHC heads are massive next to a push rod engines heads. You could potentially run into issues on a current GM vehical. Ford builds the Mustang to fit these wide engines. Not sure if a current Camaro would fit a DOHC engine between the shock towers or if the heads would clear the brake booster. Like the Coyote don’t expect it to be the engine swappers choice. LS will hold that title for a long time with good reason.
Side note I find it funny how GM only guys are exited about this but laugh at Ford all the time…
Well GM looked into this about 15 years ago and it just did not work well. It did teach them to make the bock stiffer.
They will do a dedicated engine and do it right with no compromise.
The only thing I see is a block Cadillac and Chevy share and a differen’t top end to give them different engines as a possibility.
Good news. OHV is great in most applications but for a top tier sports car / sedan I prefer DOHC engines.
SOHC and DOHC are still Over Head Valve/ Valve in Head engines.
Put another way…I prefer DOHC engines as opposed to SOHC.
Awsome news,
Long live the small block Chevy (GM). The pushrod motor may not have too many years left on the dealership floor, but it will live on for a very long time out of the crate.
It was pretty much inevitable that GM would have to move to DOHC to keep the large displacement motors in new vehicles with emissions getting tighter. A new generation is always better then discontinuation.
There is also (((this)))
IMSA regulations
While the LMP2/DPi regulations are locked in for a minimum of four years with the same constructors and chassis, Raffauf said manufacturers will be allowed to make changes to the appearance of the bodywork or even (((debut new engines))) and/or branding over that period, under an approval and homologation process.
“If they come out with a (((new engine))), they can follow the original process and rebadge and redo their car,” he said.
“The basic car remains intact but if they want to change the engine because they’re introducing a (((new product))) in that period and want to highlight that product, [the OEM] has that option.
http://sportscar365.com/industry/inside-imsas-dpi-regulations-pt-1/
Mid-engine, as in (((C8)))!!!
Cadillac has a new DOHC V8 engine Twin turbochargers (I think) 4.5-liters, coming. They are working on it now.
I believe W.O. Bentley had it right; “there is no replacement for displacement.”
These LT5 DOHC NA V8 engine will on into these C7ZR1. A version of this called LT8 DOHC v8 engine will go into these mid-engine C8 corvette, I think it will be TT.
How much will that engine weigh being a 6.2 DOHC? I am glad but sad too, I like the low end torque and light weight and smaller size. How does a DOHC engine get better fuel economy? I know the pluses of both, DOHC have more valves and torque in higher rpms etc. I just the small block chevy’s..
It will be a bit heavier and bigger, as far as torque goes, the C4 LT5 had a butterfly valve in one intake port of each cylinder (closed at low rpm). Keeping air valocity up and causing the air/fuel mix (port injection) to swirl going into the cylinder, giving it 300 lb-ft of torque at 1000rpm
The shape of the LT5 gen 5 DOHC engine will be able to fit in these engine bay of the C7 corvette.
These new Gen 5 SB LT5 DOHC V8 NA engine, is a new Gen 5 engine, with more valves, and more camshafts.
Nope!
http://www.autoblog.com/2016/12/23/2018-chevy-corvette-dohc-v8-lt5-mid-engine-rumor/
No this will be an all new engine.
GM is not like they were in the past where they had to short cut it. Today they are funded to where they can do this right and not get what they really want.
Now there could be some sharing with Cadillac but. It would be like the platforms. While sharinging to share cost they would be much different power plants.
So Scott3 these block and cylinder heads are a all new design? That has nothing to do with these LT1 and LT4 engines?
Yes I do not see any sharing of the present engine.
Even now when Chevy does a new engine the only carry over the bore space and a couple small details.
To do engines anymore a clean sheet of paper is the way to do it.
Even with a possible sharing of a cadillac block and Chevy they also could easily just do two totally new engines.
GM the corporation developes powertrains at it’s powertrain development center , they are no longer done by the individual car divisions!
While what you state is true ther is going to be more effort to make engines more unique to Cadillac.
Buick and Chevy will share most evgines but they want to give Cadillac a more exclusive engine line. It will take time but the coming v8 will be the first effort.
While doing two versions of a new motor design would add a manageable increase in cost, it could greatly increase the number of applications that it could be used in, depending on how they do it. Reducing the total cost of development per application. Resulting in a win win for the manufacturer and the consumer.
In a way, I think corporate types and engineers can miss the art of these machines. Nobody with a soul would tell Ferrari they have to dump the big V12 or Porsche the rear engine 911.
And I don’t know why, 20+ years ago and since, GM protected Chevy’s Corvette in its hierarchy. And shot down the other divisions’ mid-engine and a handful of turbos. And in effect, becoming the protector of the big-cube pushrod legacy. My personal hope is they leave nothing on the table to have a place for them.
My sense is people will eat these things up, those that can afford them, wherever they’re placed. And it’ll be a good sign, if focused divisions try to excel rather than being blocked from it. All I know is, these decisions are above my pay grade.
So much speculation over the LT5, i guess we wont have too much longer to find out. (The new ZR1 should be coming to Detroit, if its not there we know where its going). My guess is the ME Vette, I think fitting a DOHC would be an issue for the Stingray but not for the ME version. Also, just as interesting, did anyone notice the 6.2 LT4 has an additional chassis code K. Will we see that top of the line Escalade V like vehicle rumored with the LT4, one can only speculate
The way I understand it is the C8 corvette ME will get a version of these LT5 DOHC v8 engine in 2019, called LT8 TT DOHC V8 engine. These base c8 corvette ME will started in these later half of 2018 with these LT1 V8 engine.
Seriously people! What GM needs to do is to incorporate SIDI Technology into their current line of OHV V-8s. Listen up folks, the LTI V-8 gets 17mpg city and 29mpg highway vs the BMW 3.0TT M3/4 17-18pmg city and24-26 highway ratings. So who the hell are we fooling about DOHC being so superior to OHV engines in terms of mpg ratings? Further, none of the DOHC V-8s though smaller in displacement than GM 6.2 found in the SUV/Truck segment, can beat the 6.2 in mpg ratings. Additionally, not even Fords 3.5TT V-6 with its 10-speed can’t even shame GM’s OHV when it comes to fuel efficiency.
I can further emphasize that the Hennessy Venom 1244 BHP OHV 7.0 V-8 in mid-engine form, actually has mpg ratings of 15mpg city and 24mpg highway, which trumps the Ferrari 688 BHP DOHC 3.9 liter V-8. Of course I might be wrong, but anyone who has other stats can put me in my placed. So what GM needs to do is to incorporate that SIDI Twin Turbo technology in its latest OHV with better transmissions to give its trucks, SUVs and cars a performance advantage.
Valiance, the small blocks are already SIDI. If im not misktaken all of GM’s current engines have SIDI now.
Spark Ignition Direct Injection, yes all the gen 5 (Eco Tech 3) motors have it, including the 4.3L V6, which by the way is why we need a new Typhoon and Cyclone.
It is still Christmas!!!
Sounds like this engine will have very good power throughout the WHOLE rev-range.
Power down low with that big 6.2 displacement AND good Mid-High rev power with the DOHC.
Not to mention potential of being a high revving engine,
IF done right this sounds like an interesting engine.
The new Mercury Racing Engine 7.0 SB4 DOHC production begins next week. It is based on an LS7 block. Normally aspirated this small block monster outputs 775 HP @ 7,500 rpm and red lines at 8,000 rpm. It weighs ~ 500 pounds and should be lighter than a supercharged OHV pushrod engine. Back in the 90’s Lotus / Mercury supplied the ZR1 DOHC engine, so this continued collaboration between them and GM seems likely. This SB4 would easily top 1,000 HP for the streets in supercharged or turbocharged config. The only drawback I see for Corvette production is GM loads complete engines from the bottom. This engine is probably 2 inches too wide to fit up between the frame rails. All 775 HP is very useable above 40 mph in a front engine / rear drive car. I doubt America is ready for a buzzing V-6 or electric powered sports car.
Wonder what the name will be? Maybe Hammerhead? As mentioned in STARWARS.
To be honest, I don’t see the new LT5 being a forced induction engine. Here’s why. If Ford can produce a 500hp naturally aspirated 5.0L V8 engine GM can easily produce a 600hp 6.2L V8 with minimal fuss and it be a reliable everyday kind of car. Watch this, now we all know that the camaro Z/28 will see this engine, it’s a given and the Z/28 is going to be an N/A car again like it should be. Rest assured this will feature a dual injection system, variable cam timing, tubular tri-y headers, weight reduction in the rotating assembly and valve train, a revised intake manifold and induction system, the 10-speed auto and a few other things. I’m banking the car will make 630hp in the Corvette and about 620hp in the Camaro. Does it out muscle the LT4, no but what it does do is make better use of power and reduce weight and give it higher revving capabilities to make it a better all around performer. Here is what I’m hoping though for the Camaro. Now I’m a big fan of Chevrolet’s Camaro and I loved the sedate but sinister look the previous Z/28 had in the fact that it wasn’t much different than the SS, that was awesome. Now if GM keeps that same recipe and just builds on what the 1LE has done, the Z/28 will be the best Z/28 in history. Also i’m hoping they make this Z/28 with dual stripes, front fender Z/28 badges right next to the headlights, the open grilles, a lower aero package with a Z/28 specific lip spoiler & the side skirts and rear fascia from the ZL1, Z/28 specific 20×10.5 front and 20×11.5″ rear wheels and a taller duckbill spoiler with the wicker bill on the back. Now that would be an awesome Z/28