Cummins Gasoline 6.7

Rockwood

Rockwood

Well-known member
Joined
May 5, 2021
Messages
5,563
Reaction score
7,028

Been wondering how long before someone did this. The Ecoboost 3.5 in our F-150 feels almost exactly like the 5.9 I had back when, except it'll rev and has 10 speeds. Scale up the engine to understress it and use it for commercial duty, but not deal with all the diesel emissions shit? Sounds like a plan. Doubt it will be as fuel efficient as a 5.9, but probably close enough to a current diesel.
 
Seems easy enough for Cummins to produce this 6.7, the 9 liter and the 15 liter using gasoline. All three engine models are on the production line and can be built to run on LNG, Hydrogen and diesel. LNG being the closest model to convert to gasoline. It's been discussed for a few years now in dealer meetings and articles in Forbes Magazine.
 
They weigh twice as much as any comparable gasoline engine. That part doesn't make sense to me
 
Interesting.
I'll say, my 2024 6.6 Gas 2500HD motor feels like my 2004.5 LLY Diesel. The gas has 91 more hp and only 46 ft/lb LESS on torque.
Only thing that 2004.5 needed was the 6 spd trans and the 35 gallon tank.
 
Rorschach said:
They weigh twice as much as any comparable gasoline engine. That part doesn't make sense to me
Click to expand...
Medium duty shit? I suppose the Godzilla is also in MDT commercial chassis.
 
Ya I think Godzilla would be good in medium duty. Googler says Godzilla weighs 500lb and 6.7 stroker over 900. Cummins ISBs over 1100.
 
I just kinda skimmed through the article. Missed the clean sheet part but it does say that it will lead to future diesel and hydrogen derivatives that share its architecture so it'll have to be somewhat robust. Also, I was touching on what @Grease Monkey said about converting larger engines to gas. Diesel to gas just seems backward to me but I guess the emissions are the focus here.
Think that's why Caterpillar quit making truck engines bcuz the emissions were too much trouble.
 
Rorschach said:
I just kinda skimmed through the article. Missed the clean sheet part but it does say that it will lead to future diesel and hydrogen derivatives that share its architecture so it'll have to be somewhat robust. Also, I was touching on what @Grease Monkey said about converting larger engines to gas. Diesel to gas just seems backward to me but I guess the emissions are the focus here.
Think that's why Caterpillar quit making truck engines bcuz the emissions were too much trouble.
Click to expand...
Yep. Plus the butt-hurt stain on reputation.
 
Cummins has said the fuel agnostic engines are "the same from the head gasket down". Their words not mine. Freightliner M2, Paccar Mediums, Mack MD, Isuzu, and Cornbinder are all chassis that currently run the ISB 6.7 diesel. That makes it as close to plug & play as it gets. The other market they could tap is the gasser Class A market where the only option currently is the Ferd F53 chassis, which is lackluster at best. If Freightliner gets on board, there could be a much better gasser A package alternative.
 
Rorschach said:
I just kinda skimmed through the article. Missed the clean sheet part but it does say that it will lead to future diesel and hydrogen derivatives that share its architecture so it'll have to be somewhat robust. Also, I was touching on what @Grease Monkey said about converting larger engines to gas. Diesel to gas just seems backward to me but I guess the emissions are the focus here.
Think that's why Caterpillar quit making truck engines bcuz the emissions were too much trouble.
Click to expand...
1HasBeen said:
Cummins has said the fuel agnostic engines are "the same from the head gasket down". Their words not mine. Freightliner M2, Paccar Mediums, Mack MD, Isuzu, and Cornbinder are all chassis that currently run the ISB 6.7 diesel. That makes it as close to plug & play as it gets. The other market they could tap is the gasser Class A market where the only option currently is the Ferd F53 chassis, which is lackluster at best. If Freightliner gets on board, there could be a much better gasser A package alternative.
Click to expand...
And that's where I get the assembly line mention. The base engine can continue down the assembly line and a change in production can come in and move on to Diesel, LNG etc without a full on change over. Here's the lineup if your interested.

 
This might be a non starter if the EPA changes working their way through the system are indeed passed.
 
IMO, 660 lbft of torque is a far cry from the 1000 that my Powerstroke makes. The 6.7 ISB in my pusher makes 800 and is marginally enough to get my rig down the highway. So a 6.7 on gas that makes less would be a no go for me. They didn't mention fuel economy, it's probably crap. Displacement requires fuel and gasoline only has so many BTUs available. On the flipside, diesels are complicated and expensive so perhaps a new gas engine would be considerably less. Only time will tell what the tradeoff is.

Workhorse used to market a rear engine gas package for motorhomes called the UFO chassis but they used the 8.1l gas guzzling pig of an engine that wouldn't get out of it's own way. Needless to say those weren't in production very long at all.
 
Since the only game in town currently for a gasser A is the Godzilla, the Octane 6.7 would be a big step up in comparison, especially at elevation where the NA engine gets wheezy. AFAIK, as is typical, the Godzilla is detuned in MH applications, as compared to the pickup version.

The Powerstroke is also detuned in medium duty applications.
 
Fireballsocal said:
This might be a non starter if the EPA changes working their way through the system are indeed passed.
Click to expand...
Cummins is a global engine provider. Might not sell as well here, but there are plenty of markets. Plus, even if rolled back a little, there are lots of fleets that've switched entirely to gasoline because of diesel repairs and downtime.

KLC said:
IMO, 660 lbft of torque is a far cry from the 1000 that my Powerstroke makes. The 6.7 ISB in my pusher makes 800 and is marginally enough to get my rig down the highway. So a 6.7 on gas that makes less would be a no go for me. They didn't mention fuel economy, it's probably crap. Displacement requires fuel and gasoline only has so many BTUs available. On the flipside, diesels are complicated and expensive so perhaps a new gas engine would be considerably less. Only time will tell what the tradeoff is.

Workhorse used to market a rear engine gas package for motorhomes called the UFO chassis but they used the 8.1l gas guzzling pig of an engine that wouldn't get out of it's own way. Needless to say those weren't in production very long at all.
Click to expand...
I think it'll move better than its numbers suggest. It matches the existing B6.7's numbers:


And I assume there's ceiling for more power in certain applications, as always.
 
Last edited:
The ISB in moho or cab & chassis use tops out at 360/800. Pickups are 430/1075.
 
You must log in or register to reply here.
Back
Top