I have a 2011 f150 Ecoboost and I have begun contemplating upgrading the turbos. They are running about 22 psi now, and I am sure they are out of efficiency range. I know there are kits that essentially allow you to bolt on the GT turbos, and they will exceed the bottom end handling ability of the 1st gen bottom end, but I kind of wondered if it wouldn't be better to fabricate a compound setup for it. I was thinking a larger single after the Y to feed the two little turbos.

I wondered what the Hive Mind would have to say about this, all theoretical for now.

 

I personally would upgrade the turbos before going compound. The compounds excel when looking for high pressure ratios, but a properly sized set of twins should make good hp to near 30 psi.

 

I could do the drop in turbo conversion, and it would be less hassle, maybe even cheaper (it would cost around $2600). They would move enough air to destroy the stock bottom end, so they are more than adequate unless I built the engine. I know that is probably the solution to pursue in my case.

Hopefully I can state this in terms that make some sort of sense, this thread is more or less meant as a discussion and a way to learn more about the engine and the tech that goes into the ecoboost family. Maybe some day it will happen, I use the truck is primarily a tow rig for my RV and car hauler, trading to a diesel would be the ultimate solution but the cost and complexity of modern diesels is off putting to me. The ecoboost is out of warranty, and mostly paid for so its a decent platform if I decided to pursue something crazy. It is insanely comfortable, it rides beautifully and handles the trailers in a variety of conditions very very well.

Really the ecoboost does exceptionally, but when pulling Colorado mountain passes with weight on the hitch it starts to heat up pretty good, IAT's get high and the engine gets hot, then I go slow (it already has the big radiator in it). This wasn't such a big deal and I really don't mind having to slow down on the steep stuff, but if I am pulling a long enough grade at high altitude the turbos will start to surge, then its a game of figuring out to what speed I need to slow. I drive the truck with travel trailer on a lot of small back country roads, and I hate slowing traffic... I end up pulling off the side and letting people pass often, which then means getting back up to speed wasting fuel, so on. Plus people become total assholes if you cause them a seconds delay.

So I got to thinking of a compound setup: I would be wasting more exhaust, IAT would be lower, I could have more boost on tap, it seems like a win/win. The ecoboost uses computer controlled gates, and I wanted that functionality to remain for ease of tuning.. These engine build power much like a diesel, unfortunately they also run out of air so they are much like a diesel in that regard as well, torque begins dropping dramatically at 2700 RPM especially in tuned applications. The way these little turbos spool is like magic, but it definitely leaves you yearning for some high end. That is another place i believe the compound could really shine, I was thinking something in the S300 line, route it in after the merge and let it sing.

 

I have helped two friends with the same issues. A spray bar mounted in front of coolers, hooked to a remote windshield washer setup, will do wonders when making those long uphill pulls. A lot cheaper too.