GM's 6th Gen V8 ! What would you like to see?

Cojam1 · May 26

With a lot of the on going issues with current production V8 engines, What would you like to see GM produce? Build your ideal V8, But something realistic that would be mass produced.

1. A 5.3 or resurrect the 5.7 in some form,6.0 or 6.2

2. Pushrod or OHC is fine. No turbo for me.

3. Dual injectors. Multiport and direct Inj. Thereby eliminating gummed up intake valves

4. Absolutely NO DFM of any sort.

5. 385 to 420 Hp is fine / Torque Min. 400ft/lb

6. A well built 6 or 8 sp transmission is all I need.

KARNUT · May 26

8 minutes ago, Cojam1 said:

With a lot of the on going issues with current production V8 engines, What would you like to see GM produce? Build your ideal V8, But something realistic that would be mass produced.

1. A 5.3 or resurrect the 5.7 in some form,6.0 or 6.2

2. Pushrod or OHC is fine. No turbo for me.

3. Dual injectors. Multiport and direct Inj. Thereby eliminating gummed up intake valves

4. Absolutely NO DFM of any sort.

5. 385 to 420 Hp is fine / Torque Min. 400ft/lb

6. A well built 6 or 8 sp transmission is all I need.

The set up in my 2014 was perfect. 5.3 E-85, 6 speed with no cylinder deactivation. With the option of a S/C kit like Ford offer.

customboss · May 26

Hydrogen burning version with onboard electrolyzer.

the wanderer · May 29

On 5/26/2024 at 2:51 PM, Cojam1 said:

With a lot of the on going issues with current production V8 engines, What would you like to see GM produce? Build your ideal V8, But something realistic that would be mass produced.

1. A 5.3 or resurrect the 5.7 in some form,6.0 or 6.2

2. Pushrod or OHC is fine. No turbo for me.

3. Dual injectors. Multiport and direct Inj. Thereby eliminating gummed up intake valves

4. Absolutely NO DFM of any sort.

5. 385 to 420 Hp is fine / Torque Min. 400ft/lb

6. A well built 6 or 8 sp transmission is all I need.

385 hp is not going to cut it unless they continue two v8's and make the 385 very noticably better with fuel efficiency.

The 2025 Ram HO is putting out 540 hp with 520 lb-ft of torque, so a 6.2 replacement will need to play in that area. Ford will be doing an update soon as well, you know they will not concede the 0-60 time to Ram for long. So again, a 6.2 needs to up the game considerably.

I would like to see a 6.2 replacement with 500+ hp, pushrod, dual injection, no dfm, 10 speed.

For the smaller v8, focus on fuel efficiency. Keep it 350-ish hp, tuned for mpg, with architecture similar to 6.2. Maybe a tow mode that drops efficiency in favour of more power low down but this could be wishful thinking and not possible.

newdude · May 29

- Redesigned lifters and better camshafts. In a perfect world, GM should have invested in the Freevalve system Koenigsegg developed as that would enable V8s for years to come for sure, plus give them a way more reliable DFM operation.

- Dual injection isn't a bad idea I suppose.

- Possibly displacement bumps? Instead of pushing the limits of where they are now and bumping power and running them harder, go bigger to accommodate the bump but increase the reliability. So say take the 5.3 up to 5.5-5.7 and get to the 380-395hp range, and the 6.2 to 6.4 or 6.6 and go to 440-455hp.

- Scratch all V8s except for Corvette and HD trucks and go turbo inline 6 like GM was going to but then pulled the plug. They've got all the pieces to that puzzle already (the Turbomax and the 3.0 Duramax would be of the same engine family). Take the Turbomax for example which makes 310hp, 430tq, that's 77.5hp per cylinder. The base inline 6 could easily pull 465hp (using 77.5hp per cylinder) and possibly 550tq. I'd imagine a hopped up one could easily push close to 600hp and over 600tq.

KARNUT · May 29

Mostly it enthusiast who complain. Reliability is already there just lose cylinder deactivation. For enthusiast have super charger option that’s relatively cheap like Ford. I modified every Chevy engine I owned except the last one so far. Never had a reliability problem. My last 5.3 with a 354 gear got 23 mpg at 60, 22 at 72.

Gangly · June 3

The current generation of LT engines, once DOD is removed, are bulletproof. You can run the piss out of them and they will last forever. The problem, as always, has been the shortened lifespan due to the DOD system components. Fortunately I haven't experienced lifter failure yet, and have taken what I hope to be preventative measures, but its a huge worry none the less.

I would like to see the following on the next generation engine:

1. NO DOD, or at least no DOD in its current form! Come up with a better plan for fuel economy. I would gladly eat 1 mpg just to have the peace of mind that my truck will go 200K before ever having to dig through it's internals. Between Yukons, Tahoes, Silverados, etc., the lifter issues might possibly cause the end of my GM Truck/Large SUV purchases.

2. Naturally Aspirated. A simple, non-turbo, gasoline engine that is dead nuts reliable would be wonderful. Turbos add additional complications and maintenance. The 6.6 in the HD would be PERFECT in a 1500 series, if only the EPA would allow it.

3. Keep the pushrod engines. I know its counterintuitive to ask them to fix the DOD, then ask to keep the pushrod engine alive, but the pushrod engines are more compact and lighter with an OHV design as opposed to a SOHC or DOHC design. Don't get me wrong, I wouldn't complain if GM went with an OHC design, but I think the engineering behind OHV engines allows them to be more compact, lighter, and able to produce more torque "under the curve" and at lower RPMs.

4. Manual Transmission. I know its not engine related, but it would be nice to have a manual transmission option on the bare bones models(W/T and Custom). Manual transmissions are just so durable, easy to work on, repair, and replace. $500 for a new clutch every 100k+ miles is worth it.....so worth it.

silveradosid · June 5

i agree with newdude and gangly, inline turbo 6 with a 6 speed manual

64BAwagon · June 5

DOD isnt going anywhere, the Govt wont allow it. Rumors are that GM has been getting pressure to put it on the 6.6 in the HD's but so far has been able to hold them back.

KARNUT · June 5

27 minutes ago, 64BAwagon said:

DOD isnt going anywhere, the Govt wont allow it. Rumors are that GM has been getting pressure to put it on the 6.6 in the HD's but so far has been able to hold them back.

The government has mandates for emissions. It doesn’t care how you get there. Cycle deactivating gets an average of a 1/2 mile per gallon to the good per their own widow sticker during the chip shortage. I’ve read that the 4 cylinder GM puts in the trucks gets the same fuel mileage as the 5.3. Same with the new 6 cylinder in the Ram and the Hemi, Toyota the same. Of course there are situations where there’s plus in a controlled environment. When you’re driving a brick at HWY speeds it’s going to demand power. Turbo charging a little engine or using the V-8. The gas demand is going to be close to the same.

64BAwagon · June 5

1 hour ago, KARNUT said:

The government has mandates for emissions. It doesn’t care how you get there. Cycle deactivating gets an average of a 1/2 mile per gallon to the good per their own widow sticker during the chip shortage. I’ve read that the 4 cylinder GM puts in the trucks gets the same fuel mileage as the 5.3. Same with the new 6 cylinder in the Ram and the Hemi, Toyota the same. Of course there are situations where there’s plus in a controlled environment. When you’re driving a brick at HWY speeds it’s going to demand power. Turbo charging a little engine or using the V-8. The gas demand is going to be close to the same.

Dont kid yourself, they swing a pretty big stick these days. As for the Turbomax vs the 5.3, based on my last 1500 with all the DOD crap on it and the 2.7L my son owns (exact same configuration) the 4 cyl gets a mile or 2 per gallon better. Thats strictly anecdotal from our experiences. When I had my 1500 with the DOD I I paid very close attention to it. I never felt like the 4 cyl mode had the beans to move that truck at freeway speeds. It picked back and forth and I noted that every time it went in and out the instant MPG would suffer for a couple of seconds. My seat of the pants feel and observations led me to the opinion that it was zero benefit since the instant MPG was also the same if it was in 4 cyl or V8 mode. Had it not been a lease I would have disabled the DOD and then eventually removed it were it a long term ownership. I am sure they have some test data that shows otherwise but I will take my real world experience over the word of a huge corporation thats being played like a marionette by the Govt. But thats just me .... LOL

KARNUT · June 5

1 hour ago, 64BAwagon said:

Dont kid yourself, they swing a pretty big stick these days. As for the Turbomax vs the 5.3, based on my last 1500 with all the DOD crap on it and the 2.7L my son owns (exact same configuration) the 4 cyl gets a mile or 2 per gallon better. Thats strictly anecdotal from our experiences. When I had my 1500 with the DOD I I paid very close attention to it. I never felt like the 4 cyl mode had the beans to move that truck at freeway speeds. It picked back and forth and I noted that every time it went in and out the instant MPG would suffer for a couple of seconds. My seat of the pants feel and observations led me to the opinion that it was zero benefit since the instant MPG was also the same if it was in 4 cyl or V8 mode. Had it not been a lease I would have disabled the DOD and then eventually removed it were it a long term ownership. I am sure they have some test data that shows otherwise but I will take my real world experience over the word of a huge corporation thats being played like a marionette by the Govt. But thats just me .... LOL

I had no difference at HWY speed & 72 MPH. I had a programmer and my trips were to the same place during testing. It was only on going down hill when you’re not using gas anyway. At home I ran E-85 so I turned the cylinder deactivation off. My Honda on the other hand it’s on more than off, even going uphill. It seam less like my truck it has a light. I heard it with my truck through the exhaust. It wasn’t a good sound. As far as actual fuel mileage. Gearing, weight reduction and drag goes a long way gaining a mile or two per gallon. With my testing using 6 different vehicles over 11 years there’s a stretch of road from just east of Lafayette to the 10-69 split in Beaumont TX where I get my best fuel mileage no matter what vehicle. Up to four miles per gallon better. At the same speed 72 miles per hour. Going west that same stretch it’s the same average as most the rest of the trip. Two Hondas, one Genesis sedan, Hyundai Santa Fe, and a Camry all got 27 miles per gallon average. My 14 GMC got 22 miles per gallon without cylinder deactivation. They all got better in the one stretch going east on that one stretch. Dropping to 65 mile per hour they all picked up 2 miles per gallon minimum. The Hondas 4. My old avalanche got 17 at its best. That’s what 373 rear end will get you, but I’ll take it. Long story short I can get 2 miles per gallon on a stretch of road. And how fast I get up to speed. My odyssey for instance takes almost 1/2 of tank with the cruise on to reach its best MPG after merging on the highway. The CRV was much sooner even though the cruising mileage was about the same. The CRV is smaller. As you can tell with my trips east I tested a lot to amuse myself. I was surprised at the difference in vehicles 6 and 4 cylinder a size difference along with HP the cruising MPG was that similar.

64BAwagon · June 5

We had a boss at work that was assigned a Tahoe to drive. All of the fuel amounts and mileage were recorded through the fuel pumps. He stopped by one day complaining about how something must be wrong with the truck since he was getting the worst mileage of the staff vehicles. The truck was kept maintained better than 99% of the public and it never had any codes in it. The guy was a left foot braker and every time you saw him on the road the brake lights were on since he was dragging the brake. I pointed this out to him and he blew a gasket and stormed off. It never came up again.

2 things that men will typically lie about measuring, one of them is fuel mileage ! LOL

KARNUT · June 5

6 minutes ago, 64BAwagon said:

We had a boss at work that was assigned a Tahoe to drive. All of the fuel amounts and mileage were recorded through the fuel pumps. He stopped by one day complaining about how something must be wrong with the truck since he was getting the worst mileage of the staff vehicles. The truck was kept maintained better than 99% of the public and it never had any codes in it. The guy was a left foot braker and every time you saw him on the road the brake lights were on since he was dragging the brake. I pointed this out to him and he blew a gasket and stormed off. It never came up again.

2 things that men will typically lie about measuring, one of them is fuel mileage ! LOL

Actually it’s I always win at the slot machine and the other.