Want to address the pros and cons of supercharging or turbocharging gas motors in heavy vehicles that could be towing. It's come up numerous times and since I have a twin screw Kenne Bell kit on one of my excursions I think I can give some feedback.

Gas motors can take boost at WOT for short bursts, say a max of 30 secondo to 1 minute while in open loop. Say 11.5:1 AFR. The 1 min would be for a light car like a mustang. Can a V10 excursion go 1 min in open loop at WOT at 9 psi boost? Maybe but I would not do it. Would I do a wot pull up a hill while towing a 5000 lb load in my excursion? NO!

I have no idea how the ecoboost motors do it. Maybe it has something to do with direct injection.

Now low rpm boost. Closed loop boost at say 5 to 10 psi boost and 14.7 afr. This is equivilant to over 14:1 compression ratios and today's fuel cannot take this without some assistance......say methanol or E85. It would be easy for my KB to reach 5 psi boost in my excursion at part throttle going up a hill. More boost if I had a loaded trailer. A light car may only see a couple lbs boost on same hill. Doing this for say 30 seconds is ok but sustained boost up a hill for over 30 seconds is asking for trouble.

This is why I think Kenne Bell discontinued their V10 kits. Motors were probably breaking.

Now a Paxton type kit that does not boost much at low rpm may not have the same issues. The same with turbos. If sized right to only boost at a higher rpm they could work. BUT DON'T EXPECT A FORCED INDUCTION V10 OR 5.4 MOTOR TO ACT LIKE A DIESEL AND TAKE 7 PSI FOR SEVERAL MINUTES. THEY CANNOT AND WILL BREAK!! Problem is torque at lower rpm is where we need it and having boost kick in at 3500 rpm when we need torque at say 2500 rpm is no help.

Heavy gas vehicles that tow should not have forced induction.....

I get away with a SC, because I'm at 8000 ft of elevation and do not tow. I still need methonal to cool things off. 10 psi for me is equivilant to 6 psi at sea level.

So if you don't tow and have a excursion and like to hotrod it from stop light to stop light than ok supercharge it. If your above 5000 ft of elevation and don't tow supercharge it......otherwise my advise is get correct gears or build a motor with forged rods and 10:1 forged pistons and tune it to get all the on demand power you need for towing.

Just my 2 cents.

 

Ecoboost possibly have lower compression to begin with. Most boosted applications in street vehicles that are gas are low compression and obviously intercooled. I would think the important thing to monitor in a blown or turbo v10 would be egt just like on the diesels.
Also, my opinion on the ecoboost is they won't be around much past 130k or 150k miles and ford doesn't really care if they last that long. Obviously they should make it out of warranty period, most will, some won't. I don't think the d.i. offers any reliability just economy. Ford also isn't getting the mpgs they had initially hoped for with the ecoboost because they have to burn so much more fuel just to keep the exhaust valves from melting. That's a fact I've been told by a ford engineer that helped design the engine.

 

My 2011 F150 3.5L twin turbo ecoboost has 10:1 compression.

It has to be the DI that allows this high compression and turbos at the same time.

I was just reading that cummins did or does put a 2V V10 6.8L ford turbocharged motor in some of their generators. I believe they are 1800 rpm propane or natural gas motors. As propane has a pretty high (106 ish)octane rating I can see this type of setup working.