Buying a new Truck

aczlan · May 14, 2012

toppop52 said:
Why is the Eco boost hard to run on a dyno? Why would it throttle back? I don't understand.

Probably the engine ECU talking to the transmission ECU and limiting the torque in some gears to keep from losing traction and to keep the engine in its sweet spot for torque.
They said that the Dodge was doing similar things on the dyno as well.

Aaron Z

jejeosborne · May 14, 2012

toppop52 said:
Why is the Eco boost hard to run on a dyno? Why would it throttle back? I don't understand.

This helps explain it.

http://blogs.insideline.com/straightline/2011/05/dyno-tested-2011-mercedes-benz-s63-amg.html

If pulling a trailer which puts a constant strain on the engine, the turbos have time to spool up. During ramp up, they are having to play catch up with the rpm.

toppop52 · May 15, 2012

OK, but sounds like real world is more akin to chassis dyno results than engine dyno results, which as a former racer I already knew. In the world you will get variable loads, weather, traction, and road conditions, what matters is what's there when you want it, not what perfect conditions can show you you on a graph.

jejeosborne · May 15, 2012

toppop52 said:
OK, but sounds like real world is more akin to chassis dyno results than engine dyno results, which as a former racer I already knew. In the world you will get variable loads, weather, traction, and road conditions, what matters is what's there when you want it, not what perfect conditions can show you you on a graph.

I got a different take from that write up. To me the chassis dyno could not put a steady load on the engine which would replicate setting the cruise and towing a trailer or making small throttle changes to adjust speed. This issue is more a problem with the turbo motors because of the small lag during acceleration.

I agree with you when comparing a drag race car because you are petal to the metal the entire race with constant acceleration but not with a car running the Indy 500 which has a more consistent speed.

I liken it to being next to a big rig on the interstate at the bottom of a hill and hear his turbos spool up but no change in rpm. Other examples would be an engine in a train or ship with a constant load continuously. The chassis dyno can't replicate these scenarios with a constant load.

Part of the beauty of a turbo engine is this characteristic. It can build power at a constant rpm and not need to downshift nearly as often.

dodge man · May 15, 2012

I'm a big fan of the Dodge and a big fan of the hemi. I've had it in trucks and several cars and think its a great engine. That said, I don't really have any problems with the ecoboost or its technology. My gut feeling is that it would out perform a hemi a little bit, all other things being equal. How will it hold up? If Ford did a lot of testing, which I think they did, I predict it will do O.K. We will find out in the next few years.

toppop52 · May 15, 2012

jejeosborne said:
I got a different take from that write up. To me the chassis dyno could not put a steady load on the engine which would replicate setting the cruise and towing a trailer or making small throttle changes to adjust speed. This issue is more a problem with the turbo motors because of the small lag during acceleration.

I agree with you when comparing a drag race car because you are petal to the metal the entire race with constant acceleration but not with a car running the Indy 500 which has a more consistent speed.

I liken it to being next to a big rig on the interstate at the bottom of a hill and hear his turbos spool up but no change in rpm. Other examples would be an engine in a train or ship with a constant load continuously. The chassis dyno can't replicate these scenarios with a constant load.

Part of the beauty of a turbo engine is this characteristic. It can build power at a constant rpm and not need to downshift nearly as often.

Yea, I did very little drag racing but in that regard you are correct. I raced Trans Am regionals in a '75 Firebird Formula and raced go karts for 15 years.
I've owned both turbos and Roots style superchargers and one centrifugal sc many decades ago on the centrifugal. I certainly don't discount them, my 2.0 turbo was a screamer in it's day. I'm just not sure that it's going to be the best combo for a person that tows even moderate loads on a regular basis, but time will tell.

jejeosborne · May 15, 2012

dodge man said:
I'm a big fan of the Dodge and a big fan of the hemi. I've had it in trucks and several cars and think its a great engine. That said, I don't really have any problems with the ecoboost or its technology. My gut feeling is that it would out perform a hemi a little bit, all other things being egual. How will it hold up? If Ford did a lot of testing, which I think they did, I predict it will do O.K. We will find out in the next few years.

I agree 100% and also think there are many good motors by each manufacturer.

jejeosborne · May 15, 2012

toppop52 said:
Yea, I did very little drag racing but in that regard you are correct. I raced Trans Am regionals in a '75 Firebird Formula and raced go karts for 15 years.
I've owned both turbos and Roots style superchargers and one centrifugal sc many decades ago on the centrifugal. I certainly don't discount them, my 2.0 turbo was a screamer in it's day. I'm just not sure that it's going to be the best combo for a person that tows even moderate loads on a regular basis, but time will tell.

What concerns you about towing moderate to heavy loads on a regular basis?

deerefan · May 15, 2012

jejeosborne said:
I agree 100% and also think there are many good motors by each manufacturer.

What a lot of the back and forth boils down to is someone's insecurities about what they purchased and if they get positive feedback regarding their purchase then they feel better about it. GM and Dodge engines, though reliable, are dated. Ford is being innovative and some are threatened by this (including me, I like my motors simple, easy to work on). I own a 2011 Silverado 4wd with the 5.3. It fits my needs fine and is tried and true. I like the idea of the eco boost, just want to see how it does in the F150 for a couple years. From what I hear, GM is planning a V6 that is either supercharged or turbo in 2013-14. It looks like the tide is turning. The Hemi and LS motors will no longer be the only high hp/torque option for GM and Dodge in the near future. That may not be a bad thing.

jejeosborne · May 15, 2012

deerefan said:
What a lot of the back and forth boils down to is someone's insecurities about what they purchased and if they get positive feedback regarding their purchase then they feel better about it. GM and Dodge engines, though reliable, are dated. Ford is being innovative and some are threatened by this (including me, I like my motors simple, easy to work on). I own a 2011 Silverado 4wd with the 5.3. It fits my needs fine and is tried and true. I like the idea of the eco boost, just want to see how it does in the F150 for a couple years. From what I hear, GM is planning a V6 that is either supercharged or turbo in 2013-14. It looks like the tide is turning. The Hemi and LS motors will no longer be the only high hp/torque option for GM and Dodge in the near future. That may not be a bad thing.

I believe what you are saying. I have never had any insecurity about my purchase but don't like it when others what to bad mouth what I have chosen. Especially when they have no experience with that particular vehicle. I don't feel comfortable bad mouthing anything others may own until provoked.

It will be interesting to see where this trend of technology goes.

Jeff