Good Sam Club Open Roads Forum: Ecoboost vs. V8 - Can you explain?
Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tow Vehicles

Open Roads Forum  >  Tow Vehicles

 > Ecoboost vs. V8 - Can you explain?

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 8  
Prev  |  Next
womps

Olds

Senior Member

Joined: 08/22/2008

View Profile


Offline
Posted: 09/04/19 09:40am Link  |  Quote  |  Print  |  Notify Moderator

srt20 wrote:

Inline maybe a better design, but they just dont fit in vehicles well anymore. Curved down hoods, shorter front ends, etc. The V block engines barely fit now. Look under the hood of a V8 diesel with turbos. Its shoved way under the cowl, and all the way to the radiator support. Then add 2 more cylinders to that length...

BTW I have a 3.5L Ecoboost. And either I have a bad one or there's alot of people that fib about their mpg. I got 7.9mpg towing a 30ft enclosed all aluminum 7.5ft wide trailer that weighed about 5000lbs loaded. And I havent seen 20mpg on the EVIC (which always reads high) in a LONG time.

Turbocharged gas engines need fuel.


GM has accomplished this fitting their inline 6 Duramax in their 1/2 ton trucks.

ShinerBock

SATX

Senior Member

Joined: 02/22/2015

View Profile



Posted: 09/04/19 09:49am Link  |  Quote  |  Print  |  Notify Moderator

As I stated before, I got to drive two 3.5L Ecoboost F150s putting over 100k on each. My personal truck was an F150HD crew cab 4x4 with 3.73 rear gears. My work truck was a F150 super cab 4x2 with 3.15 rear gears which replaced an F150 5.0L super cab 4x2 with 3.55 gears.

My personal Ecoboost truck got better fuel mileage towing and unloaded then the 5.0L work truck I had. The work truck Ecoboost got much better fuel mileage unloaded, but about the same when towing probably due to the engine having to compensate for the very tall for a truck 3.15 gears.

However, these were two different animals when towing. I had to tow a 20ft enclosed trailer with both on a routine basis to deliver bulk parts to an oilfield customer I had back then that was about an hour and a half away. The work truck 5.0L with 3.55 was gutless down low and would down shift to 3rd or 4th at the sight of a hill when down. I have had my foot to the floor on a few occasions.

The work truck EB with 3.15's would power up slight hills in 6th, and would drop down to 5th on the steeper ones. It was very rare that it would drop to 4th, but I never had my foot to the floor unless I was passing which there was always plenty left over if needed.

My experience is that while the EB does use more fuel when towing, it is not much different than any other V8 I have driven. The one main advantage versus a V8 is when unloaded. With the amount of low end that the EB, you can do the same job(or more) with tall gears in the EB that would require shorter gears in the V8. My work truck EB with a 3.15 ratio could have easily done the same that a 5.0L with a 3.73 rear gear could have done.

troubledwaters

Potomac

Senior Member

Joined: 02/17/2017

View Profile


Offline
Posted: 09/04/19 11:03am Link  |  Quote  |  Print  |  Notify Moderator

srt20 wrote:

Inline maybe a better design, but they just dont fit in vehicles well anymore. Curved down hoods, shorter front ends, etc. The V block engines barely fit now. Look under the hood of a V8 diesel with turbos. Its shoved way under the cowl, and all the way to the radiator support. Then add 2 more cylinders to that length...

BTW I have a 3.5L Ecoboost. And either I have a bad one or there's alot of people that fib about their mpg. I got 7.9mpg towing a 30ft enclosed all aluminum 7.5ft wide trailer that weighed about 5000lbs loaded. And I havent seen 20mpg on the EVIC (which always reads high) in a LONG time.

Turbocharged gas engines need fuel.
You must have a bad one. I have about 1,000 miles towing with mine and I consistently get about 10 mpg; I stay at or under 70 mph. Worse I ever got was 9.9.

librty02

Western Pa

Senior Member

Joined: 03/15/2009

View Profile


Offline
Posted: 09/04/19 12:43pm Link  |  Quote  |  Print  |  Notify Moderator

srt20 wrote:

Inline maybe a better design, but they just dont fit in vehicles well anymore. Curved down hoods, shorter front ends, etc. The V block engines barely fit now. Look under the hood of a V8 diesel with turbos. Its shoved way under the cowl, and all the way to the radiator support. Then add 2 more cylinders to that length...

BTW I have a 3.5L Ecoboost. And either I have a bad one or there's alot of people that fib about their mpg. I got 7.9mpg towing a 30ft enclosed all aluminum 7.5ft wide trailer that weighed about 5000lbs loaded. And I havent seen 20mpg on the EVIC (which always reads high) in a LONG time.

Turbocharged gas engines need fuel.


Yep you must have got a bad one, had the improper gearing, too high speed...etc
I've towed over 60k now with my 2 ecos and they consistently get 10 or better and that is not per that lie o meter that is hand calculated. The lie o meter always tells me above 11 and that is towing my 7000lb 30 foot travel trailer through the mountains of pa, west virginia, and north carolina. All engines need fuel and my 2 turbo charged ecos require less fuel to do the same as any naturally aspirated gas engine I have owned towing or not...the 5.4 and 5.0 being the absolute worst...


2011 FORD F-150 FX4 CREW CAB ECO...
2018 Ford F-150 Max Tow Crew 6.5 3.5 Eco...
2013 Keystone Passport 2650BH, EQUAL-I-ZER 1K/10K

danrclem

Ky.

Senior Member

Joined: 12/25/2015

View Profile


Online
Posted: 09/04/19 02:21pm Link  |  Quote  |  Print  |  Notify Moderator

APT wrote:

[image]

Area under the torque curve is what most drivers notice. The green line shows how much torque is available under about 4500rpm than any other compared engine.


I haven't ever had an engine with a turbo so I'd like to know how they work. First of all that's a very impressive torque curve for the Eco Boost. I wish my 6.2 had one like that. When it's running 2,000 rpms would the amount of torque shown be with the turbo running? Does the turbo start running at a certain rpm or at a certain level of throttle position? If the turbo isn't running at 2,000 rpms would the torque be less?

Just wanting to understand a little more.

ShinerBock

SATX

Senior Member

Joined: 02/22/2015

View Profile



Posted: 09/04/19 02:42pm Link  |  Quote  |  Print  |  Notify Moderator

danrclem wrote:



I haven't ever had an engine with a turbo so I'd like to know how they work. First of all that's a very impressive torque curve for the Eco Boost. I wish my 6.2 had one like that. When it's running 2,000 rpms would the amount of torque shown be with the turbo running? Does the turbo start running at a certain rpm or at a certain level of throttle position? If the turbo isn't running at 2,000 rpms would the torque be less?

Just wanting to understand a little more.


Yes, the amount shown is with the turbo running. The turbos start to spool at a very low rpm and I am not sure you could even get the truck to shift into an rpm they can't build boost at. Under normal acceleration, you will start to build boost as low as 1,200 rpm. They are mainly low to mid rpm turbos and loose their breath at higher rpms past 4,500. This is good for quick responsiveness while towing and normal driving, but not so much on the drag strip.

If you push the pedal to the floor there is a little turbo lag, but I would be surprised if it was longer than a second.

srt20

Wisconsin

Senior Member

Joined: 02/15/2009

View Profile


Offline
Posted: 09/04/19 02:59pm Link  |  Quote  |  Print  |  Notify Moderator

danrclem wrote:

APT wrote:

[image]

Area under the torque curve is what most drivers notice. The green line shows how much torque is available under about 4500rpm than any other compared engine.


I haven't ever had an engine with a turbo so I'd like to know how they work. First of all that's a very impressive torque curve for the Eco Boost. I wish my 6.2 had one like that. When it's running 2,000 rpms would the amount of torque shown be with the turbo running? Does the turbo start running at a certain rpm or at a certain level of throttle position? If the turbo isn't running at 2,000 rpms would the torque be less?

Just wanting to understand a little more.


The turbine side (wheel with fins like a fan) of the turbo is in the exhaust stream. Anytime your engine is running, your turbo is spinning.
The compressor side (same, like a fan) of the turbo is in the intake tract. This also spins anytime the engine is running.

The turbine wheel and compressor wheel are connected together via a shaft.

At idle the engine is drawing in more air then the turbo is pushing.

At certain throttle and load parameters, the turbo will start to push more air than the engine is pulling in. Thats boost.

The more exhaust your engine makes, the faster the turbo will spin. Up until the wastegate opens. The wastegate is an exhaust "dump" to only allow so much exhaust through the turbo. This therefore is another control of how much boost is being pushed into the engine.

Just a brief explanation of a turbo.
I could literally write for half a day explaining this. So if you want an indepth understanding, its just best to google it or youtube it.

Sport45

Not far enough from Houston, TX

Senior Member

Joined: 09/24/2001

View Profile


Offline
Posted: 09/04/19 09:10pm Link  |  Quote  |  Print  |  Notify Moderator

danrclem wrote:

APT wrote:

[image]

Area under the torque curve is what most drivers notice. The green line shows how much torque is available under about 4500rpm than any other compared engine.


I haven't ever had an engine with a turbo so I'd like to know how they work. First of all that's a very impressive torque curve for the Eco Boost. I wish my 6.2 had one like that. When it's running 2,000 rpms would the amount of torque shown be with the turbo running? Does the turbo start running at a certain rpm or at a certain level of throttle position? If the turbo isn't running at 2,000 rpms would the torque be less?

Just wanting to understand a little more.


Yes the turbo is spinning. Keep in mind when you review charts such as this one the data is taken at wide open throttle. You don’t make that much torque with any of the engines when you’re just loafing along. What the chart depicts is the most torque the engine is capable of producing through its rpm band.


’19 F350 SRW CCLB PSD Fx4
'00 F250, CC SWB 4x2, V-10 3.73LS. (sold)
'83 F100 SWB 4x2, 302 AOD 3.55. (parked)
'05 GMC Envoy 4x2 4.2 3.73L.
'12 Edge 2.0 Ecoboost
'15 Cherokee Trailhawk


Groover

Pulaski, TN

Senior Member

Joined: 10/17/2007

View Profile


Offline
Posted: 09/05/19 06:12am Link  |  Quote  |  Print  |  Notify Moderator

"If you push the pedal to the floor there is a little turbo lag, but I would be surprised if it was longer than a second. "

The turbo diesels that I have had experience with have very noticeable lag and may even exceed a second. On the other hand, I have never noticed lag on my Ecoboost gas engine even though I am sure that it has to have some. I assume that it is because the Ecoboost has a small turbo for getting started and then does a seamless transition to the large one as it speeds up while the diesels only have one turbo plus they need a lot more boost to get full power.

ShinerBock

SATX

Senior Member

Joined: 02/22/2015

View Profile



Posted: 09/05/19 07:08am Link  |  Quote  |  Print  |  Notify Moderator

Most modern diesels with VG turbos have very little lag. I would compare the turbo lag of my stock turbo on and stock tune my Cummins to the turbos on my old Ecoboost. With a tune, the turbo lag on my Cummins wasn't even noticeable. With a diesel, you can tune out turbo lag(to a point) since they are regulated by fuel, and not air like gas engines. Older diesel with fixed geometer turbos had a considerable amount of lag, but would have less lag if the latest turbo technology was applied to them.

With my current S364.5/80/.91 turbo, the lag is about what it was stock without a tune, but the turbo comes on much stronger with more air flow while keeping the EGT's and drive pressure much lower than the stock VGT. My current turbo has a lighter forged wheel, better ball bearings, and a T4 pulse manifold (first three cylinders are split form the last three) which aides in response time.

From what I have seen from various videos about the Ecoboost, Ford programmed the EB to open both the intake and exhaust valves if possible for a brief second when going wide open throttle to get the more air flow to the turbos quicker. I still noticed lag when going wide open throttle on a 30 mph roll. It was not much, but it was still there.

While the size of the turbo plays a large role in spool time, so does things like A/R ratio, bearing type, compressor/turbine wheel weight, blade configuration, type of turbo(i.e. twin scroll, VG, or FG), and so on. Turbos can be configured to increase power levels at various rpms, but it is often a give and take with most singe fixed geometery turbos. If you have turbo that spools quickly and makes good power from low to mid, then it will likely loose its breathe on the top end as it goes out of its efficiency zone. The reverse will be true with a large turbo that makes top end power. It will take more rpms to spool and have a considerable amount of lag, but will have enough air to at high rpms.

As I said before, Ford seem to size the turbos on the 3.5L Ecoboost for low to mid rpm power. This is good for low rpm spool and quick response, but it is still a fixed geometry turbo and will have turbo lag regardless. It may be diminished so that most will not notice it, but it will always be there unless they add twin compound or VGT turbo setup.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 8  
Prev  |  Next

Open Roads Forum  >  Tow Vehicles

 > Ecoboost vs. V8 - Can you explain?
Search:   Advanced Search

Search only in Tow Vehicles


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:

© 2019 CWI, Inc. © 2019 Good Sam Enterprises, LLC. All Rights Reserved. | Terms of Use | PRIVACY POLICY | YOUR PRIVACY RIGHTS