Ecoboost vs. V8 - Can you explain?
I'm nowhere near being a gearhead, and I can't seem to wrap my mind around how the Ecoboost outperforms the V8 in towing. I understand the fuel economy issue, but how is it that the V6 can actually h...
Forum Discussion
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.
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.
