New twin turbo six coming to Stellantis

[2kwik4u]

Part of the reason they get good mileage is by finding ways to make buttloads of torque/HP. Takes less energy/power/RPM's to make them move/get going. Same thing while towing. If you're having to wring out your motor at 6k RPMs to tow a boat you'll burn way more fuel than I will at 1900 rpms cause I have gobs of torque at my disposal.

The problem with a turbo motor and towing is keeping the EGT's (and chamber temps in general) at a manageable level. To combat this, you'll see the AFR's run pretty rich by performance standards. You aren't using the fuel to make more go, you're using to to keep the cylinders from melting themselves.

In an otherwise performance only applications, that kind of loading isn't sustained for very long because you end up well over legal speeds. Add an uphill and a 5k lb trailer and suddenly you have extended periods of boost application, and even the best intercoolers can't keep the combustion temps down. Also, keep in mind that power comes from air not fuel, and if you're running 14.7psi (gage pressure) of boost on a 3.5L, you're effectively pumping 7.0L worth of normally aspirated air mass through the engine. You only gain your efficiencies when you're out of boost and only running on 3.5L of air being pumped (downhills, steady state are mid power levels, etc).

I would love to see someone really lean on an ecoboost when towing, HOWEVER use water or methanol injection, and keep the AFR at a more reasonable level. I would wager your fuel economy would rise to be more inline with what you would expect the displacement to reflect.

 

[djetok]

We were at a small NHRA event this weekend. They had an economy dragster class. 2.0-liter Eco boost or Hayabusa engines. The eco's were running 200 mph 1/4-mile trap speeds. Pretty impressive!

 

[suke]

The problem with a turbo motor and towing is keeping the EGT's (and chamber temps in general) at a manageable level. To combat this, you'll see the AFR's run pretty rich by performance standards. You aren't using the fuel to make more go, you're using to to keep the cylinders from melting themselves.

In an otherwise performance only applications, that kind of loading isn't sustained for very long because you end up well over legal speeds. Add an uphill and a 5k lb trailer and suddenly you have extended periods of boost application, and even the best intercoolers can't keep the combustion temps down. Also, keep in mind that power comes from air not fuel, and if you're running 14.7psi (gage pressure) of boost on a 3.5L, you're effectively pumping 7.0L worth of normally aspirated air mass through the engine. You only gain your efficiencies when you're out of boost and only running on 3.5L of air being pumped (downhills, steady state are mid power levels, etc).

I would love to see someone really lean on an ecoboost when towing, HOWEVER use water or methanol injection, and keep the AFR at a more reasonable level. I would wager your fuel economy would rise to be more inline with what you would expect the displacement to reflect.

Absolutely! There's definitely more meat on this bone. I do my best to try to keep out of the throttle to keep the boost levels as low as possible. That's one thing I wish my truck had was a boost gauge in the stock cluster. I think the higher trims actually do. I'd like to see what I'm running.

 

[BlkGS]

And you want a Hellcat Durango?

For me, yes. I'm nuts and want 700hp. My wife is a practical and smart woman who has no need for it, lol.

 

[BlkGS]

I wanted a Ram when I was truck searching but the fuel mileage is what turned me off. Can't beat that interior like you said. I get 19-20mpg around town and 23-24mpg on the highway with the cruise set at 73-75mph.
View attachment 174402

That's about what my 5.0 platinum got, but it only had the 6 speed. I think it was more like 23 to 24 highway. It was actually cheaper to fuel than the STI that replaced it, that got 26 highway on premium, lol.

 

[suke]

That's about what my 5.0 platinum got, but it only had the 6 speed. I think it was more like 23 to 24 highway. It was actually cheaper to fuel than the STI that replaced it, that got 26 highway on premium, lol.

If I didn't have the max tow I'd probably get better than that, but I do love the 36 gallon tank. Did yours have the 3.15 or 3.31's? Gearing undoubtedly hurt my gas mileage.

 

[2kwik4u]

If I didn't have the max tow I'd probably get better than that, but I do love the 36 gallon tank. Did yours have the 3.15 or 3.31's? Gearing undoubtedly hurt my gas mileage.

Gearing hurts you less on a small displacement turbo motor as compared to a large V8.

Consider the V8 is spinning 2.5k rpm at cruise and the V6 is spinning 3.0K rpm at cruise. The 3.5L is still taking in less air per minute than the 5.0L is. Even at modest (below positive psig boost) levels. It scales linearly so you would need 3.2k on the 3.5L to take the same air in as the 5.0L.......assuming same load nad throttle positions. So you don't get a 1:1 benefit, but you can run marginally shorter gears in the smaller motor and get some of the torque multiplication benefits without some of the high cruising rev downfalls.

Side thought......I have wanted to stuff a DOHC 4.2 from a trailblazer into an S10 with a big turbo on the side of it for decades. Sounds like a fun project . Saw a guy put a turbo on the I-5 that GM had in the Colorado. Made a really interesting noise and made good power.

 

[suke]

Gearing hurts you less on a small displacement turbo motor as compared to a large V8.

Consider the V8 is spinning 2.5k rpm at cruise and the V6 is spinning 3.0K rpm at cruise. The 3.5L is still taking in less air per minute than the 5.0L is. Even at modest (below positive psig boost) levels. It scales linearly so you would need 3.2k on the 3.5L to take the same air in as the 5.0L.......assuming same load nad throttle positions. So you don't get a 1:1 benefit, but you can run marginally shorter gears in the smaller motor and get some of the torque multiplication benefits without some of the high cruising rev downfalls.

Side thought......I have wanted to stuff a DOHC 4.2 from a trailblazer into an S10 with a big turbo on the side of it for decades. Sounds like a fun project . Saw a guy put a turbo on the I-5 that GM had in the Colorado. Made a really interesting noise and made good power.

True, but if I could spin at 1200 rpms rather than 2k rpms I'd net better MPG. Comparing my truck against itself that is. Not against the V8.

 

[2kwik4u]

True, but if I could spin at 1200 rpms rather than 2k rpms I'd net better MPG. Comparing my truck against itself that is. Not against the V8.

To a point yes. There is a relative minimum that could be found as it relates to throttle opening vs speed in a given gear. Sometimes you're best economy will be at a middle range revs, not just the lowest possible revs.

 

[djetok]

If I didn't have the max tow I'd probably get better than that, but I do love the 36 gallon tank. Did yours have the 3.15 or 3.31's? Gearing undoubtedly hurt my gas mileage.

@suke I have had multiple F-150's 3.5l pulling all had 10 speeds. I got my best gas mileage with the 3.55. My 3.31 was close but less, you could also tell the difference at 70 mph between the 3.55 and 3.31. Also for a short period, I pulled with a 2.7 4x4 with 3.55s. I would go 3.55 with 3.5l for the best economy.

 

[BlkGS]

Part of the reason they get good mileage is by finding ways to make buttloads of torque/HP. Takes less energy/power/RPM's to make them move/get going. Same thing while towing. If you're having to wring out your motor at 6k RPMs to tow a boat you'll burn way more fuel than I will at 1900 rpms cause I have gobs of torque at my disposal.

That's not true though. Torque requires fuel, sure you can do some tricks to extra more useful energy from it, but at the end of the day, the power comes from fuel. Those gobs of torque come from boost and gobs of fuel. It's not just free cuz turbo, lol.

 

[BlkGS]

If I didn't have the max tow I'd probably get better than that, but I do love the 36 gallon tank. Did yours have the 3.15 or 3.31's? Gearing undoubtedly hurt my gas mileage.

I want to say it had 3.55s? Maybe 3.73? I had whatever the most aggressive gear was because I was coming from a Corvette and didn't want to be bored.

I was unsuccessful in that btw. It was a total dud to drive. Super comfortable and nice, but basically a nap. But I'm really not a truck guy, lol.

 

[suke]

That's not true though. Torque requires fuel, sure you can do some tricks to extra more useful energy from it, but at the end of the day, the power comes from fuel. Those gobs of torque come from boost and gobs of fuel. It's not just free cuz turbo, lol.

That's the same across all platforms though, that aren't electric that is.

I want to say it had 3.55s? Maybe 3.73? I had whatever the most aggressive gear was because I was coming from a Corvette and didn't want to be bored.

I was unsuccessful in that btw. It was a total dud to drive. Super comfortable and nice, but basically a nap. But I'm really not a truck guy, lol.

I'm the opposite. I'm not a sportscar guy. I had sportbikes for years when I was younger and that scratched my itch for speed. I'm 6'4" and getting into most cars requires me folding in half. LOL! I DD'ed an S2000 for a year. Car was awesome and I stumbled into it buying it from a buddy of mine. Kept it for a long time and it was fun to drive in spurts. I'm also not a truck guy. I've owned Jeeps most of my driving career. Wife drives my wrangler I bought a few years back. Now that I've had a truck I will forever have one. It's just so dang useful.

 

[BlkGS]

That's the same across all platforms though, that aren't electric that is.

I'm the opposite. I'm not a sportscar guy. I had sportbikes for years when I was younger and that scratched my itch for speed. I'm 6'4" and getting into most cars requires me folding in half. LOL! I DD'ed an S2000 for a year. Car was awesome and I stumbled into it buying it from a buddy of mine. Kept it for a long time and it was fun to drive in spurts. I'm also not a truck guy. I've owned Jeeps most of my driving career. Wife drives my wrangler I bought a few years back. Now that I've had a truck I will forever have one. It's just so dang useful.

I don't fit into the s2000 either at 6'2, lol. I've been a vette guy for a while now. I've had 2 trucks, I liked my Colorado a lot more than my f150 because it was smaller and sportier. Also, it was cheap and paid for so I had no fear of using it for truck stuff. I got dumploads of mulch and dirt in it, shoveled it out of the bed, no big deal. Probably would have kept it longer but it was just a little bit too small with the little guy being born.

 

[2kwik4u]

Now that I've had a truck I will forever have one. It's just so dang useful.

I regret not going truck again when I had to dump my Sierra. They are the swiss army knife of the automotive world IMO. DO soo many things well it's really hard to argue with the value of a fullsize pickup.

 

[BlkGS]

I regret not going truck again when I had to dump my Sierra. They are the swiss army knife of the automotive world IMO. DO soo many things well it's really hard to argue with the value of a fullsize pickup.

I would counter it's hard to argue the value of a 500 dollar utility trailer over a truck, lol.

 

[2kwik4u]

I would counter it's hard to argue the value of a 500 dollar utility trailer over a truck, lol.

While you're not wrong. There is a certain level against it in terms of storage and having one more thing to manage. Registration and taxes are also on the list of BS that comes with a trailer.

Also, I can't find one for $500 that's larger than a 4'x8'

With that said, I'm likely to end up with one here in the coming months. The boys both have dirtbikes now, and the hitch carrier is a PIA to deal with.

Aside from a little bit of hassle. Home Depot will rent you one for ~$50/day or so. I've rented one a couple times now. They're actually quite nice trailers.

 

[suke]

I don't fit into the s2000 either at 6'2, lol. I've been a vette guy for a while now. I've had 2 trucks, I liked my Colorado a lot more than my f150 because it was smaller and sportier. Also, it was cheap and paid for so I had no fear of using it for truck stuff. I got dumploads of mulch and dirt in it, shoveled it out of the bed, no big deal. Probably would have kept it longer but it was just a little bit too small with the little guy being born.

I hear ya on using the truck for truck stuff. I'm fairly OCD about my stuff and getting it dirty tends to make me cringe at times. I used to have a honda ridgeline which everyone gave me shit about, BUT I did more truck stuff with that "truck" than most people did with their half tons.


That's on a hill, but that's a full pallet of wet sod. Had no idea how heavy that stuff was, but it was my beater.

 

[BlkGS]

I hear ya on using the truck for truck stuff. I'm fairly OCD about my stuff and getting it dirty tends to make me cringe at times. I used to have a honda ridgeline which everyone gave me shit about, BUT I did more truck stuff with that "truck" than most people did with their half tons.
View attachment 174445

That's on a hill, but that's a full pallet of wet sod. Had no idea how heavy that stuff was, but it was my beater.
View attachment 174446

That was my Colorado. I used it to tow my boat home when I bought it (turns out the trailer had no brakes and I didn't know), I drove it into my backyard to deposit mulch and dirt, tons of decking, appliances, mattresses... And it was a lowered 2wd sport suspension v8 truck, lol. I did more truck stuff with that Han I did with my f150, hell I did more truck stuff with that than many of my friends did with their big 1500 and 2500s, lol.

Bought it for 10 grand, put like 50 or 60k on it, sold it for 6500, with an engine tick. Probably my fault, I ran it a few times thinking the book called for 5 qts of oil, not 6, and I ran it hard.

 

[BlkGS]

While you're not wrong. There is a certain level against it in terms of storage and having one more thing to manage. Registration and taxes are also on the list of BS that comes with a trailer.

Also, I can't find one for $500 that's larger than a 4'x8'

With that said, I'm likely to end up with one here in the coming months. The boys both have dirtbikes now, and the hitch carrier is a PIA to deal with.

Aside from a little bit of hassle. Home Depot will rent you one for ~$50/day or so. I've rented one a couple times now. They're actually quite nice trailers.

Tractor Supply rents nice aluminum trailers as well, pretty cheap too.

I thought about buying a folding harbor freight one, my hoa would shit a brick if I bought a trailer and didn't hide it in my garage.... Which is already full of sports cars and stuff. I think I could stuff the folding HF one in there.