Why No Pushrod Modern 4's and V-6's?

[Skippy722]

it is still expensive in the sense that the way of manufacturing versus marginal scale in cost does not make it practical. And the VVT is still limited in what it is able to do. The pushrod engines being made are still compensated in overall café targets because if i am not mistaken are made in limited quantities? I could be wrong on limited quantities.

Yep. Even Stellantis is scaling back. Used to be able to get a V8 in pretty much any trim level Durango or Grand Cherokee. Now you only get the V8 in the R/T or as an optional extra on the Citadel (excluding SRT models). Same for the Grand Cherokee, the new one you only get it in the top trim levels as an option.

 

[350Rocket]

There is an LS-based pushrod V6 now that came out a few years ago. It is 4.3L, 3/4 of the LS1, making 285 hp. It's is the standard engine on GM's full-size vans. They just stopped using it in the Silverado/Sierra. Too bad they don't offer it in the Colorado/Canyon

Too bad there is no cheap I4 pushrod, though. The 122 is cheap and simple.

It's based on the LT (direct injection) engine that came out in the trucks in 2014 I believe, along with the rest of the new generation of 5.3/6.2. One of our company trucks is a 2015 Silverado with that engine.

 

[350Rocket]

What i like about pushrod engines is their heads are usually more compact. Especially the older era of engines.

I like that they're easier to work on in most applications. Specifically in a work truck like I have that I want to last for 30+ years. Although I was surprised the 5.0 in the newer f150s doesn't look too badly crammed in there.

 

[350Rocket]

I can remember when the CX500 was first introduced and it came as quite surprise that Honda had made a relatively low tech pushrod V twin when OHC in line 4's had become near universal for a Japanese bike at the time. It must have been a consideration that a pushrod engine would keep the width down on an across the frame V twin. It did the job very well and was refined into the bargain. Very much a confirmation that push rod engines could still be the appropriate choice.

I can think of another example of a pushrod engine being still fit for purpose and that was the Rolls Royce 6.7 litre V8 that was in production from 1959 until 2020. They did some major upgrades to it during that time and had the opportunity to go to OHC 4 valve but a push rod 2 valve design proved to have the lowest noise levels so they kept producing it.

I still own this bike, sitting in my dad's garage with a lot of parts taken off. It was a project my old roommate started and he's no longer with us, so in determined that one day I'll put it back together and get my motorcycle license again.

 

[vwmaniaman]

Why did Mopar V8's with push rods last so long. My Hemi has plenty of power. My 5.2 Magnum has enough power.

 

[OVERKILL]

Yep. Even Stellantis is scaling back. Used to be able to get a V8 in pretty much any trim level Durango or Grand Cherokee. Now you only get the V8 in the R/T or as an optional extra on the Citadel (excluding SRT models). Same for the Grand Cherokee, the new one you only get it in the top trim levels as an option.

Apparently they are doing another run of the Hellcat Durango according to my buddy that owns the dealership. He has one from the first run, which they said was going to be the only, limited, run of them, so he's not thrilled that they've decided to do another, lol.

 

[clinebarger]

Because pushrod engines have poor power density compared to any even remotely well executed 4-valve per cylinder engine.

1. Compared to a 4-valve/cyl engine? Only if the LS has a significant displacement advantage

Let's take a Mustang with a 5.0L Coyote & a LS3 6.2L Camaro......Sure the Camaro has a displacement advantage, But they get about the same fuel economy & performance is pretty similar.

So what does the Coyote have to show for it's greater power density besides being physically larger, More complex, And heavier?

 

[Allaneddie]

Why did Mopar V8's with push rods last so long. My Hemi has plenty of power. My 5.2 Magnum has enough power.

The 318 was a great engine and it was lifted up and made into the greater 340.

 

[Cujet]

Why did Mopar V8's with push rods last so long. My Hemi has plenty of power. My 5.2 Magnum has enough power.

Low operational RPM might be a factor that does not apply to similarly heavy vehicles with half an engine.

 

[ESP9935]

Let's take a Mustang with a 5.0L Coyote & a LS3 6.2L Camaro......Sure the Camaro has a displacement advantage, But they get about the same fuel economy & performance is pretty similar.

So what does the Coyote have to show for it's greater power density besides being physically larger, More complex, And heavier?

The Mustang's Gen 3 5.0 offers a wider working power-band with superior average power to the LT1 - that's part of the reason why the Gen 3 5.0 Mustang will typically walk away from a 6th Gen SS on the top end despite being a heavier car that's also down 70 cubic inches.

Regarding the LS3 Camaro versus the Gen 1 5.0:





I guess by some standards that's pretty similar - but that ambiguous metric surely didn't make the LS3 Camaro owners that pretty consistently lost to the 5.0 Mustangs feel any better.

 

[Cujet]

they get about the same fuel economy & performance is pretty similar.

So what does the Coyote have to show for it's greater power density besides being physically larger, More complex, And heavier?

Those are simply manufacturing and marketing choices. They are both produced to compete with each other and to a lesser extent, the other V8 powered brands. If it were not so, GM would be selling 427cubic inch 505HP Camaro's as SS models. And maybe Ford would be installing the 6.2L or 7.3L pushrod V8's.

In the end, I don't care which one I drive. I do like the generally pleasant nature of a V8. I drive Ecoboost stuff too, I find them less pleasing, as the big V6 sounds like a UPS truck, groaning when asking for power. On 1000 mile drives, it matters.

 

[BMWTurboDzl]

So sick of people thinking the valve configuration has anything to do with where an engine makes its peak torque.

The arrangement of the valve actuation has NOTHING to do with the power curve. Yes, OHC engines may be able to rev higher, but the torque and power curves are dictated by bore, stroke, and cam PROFILE.

Would you agree that it's more difficult to implement VVT with a pushrod set up?