Turbocharged gas 460 or 454?

Just for the sake of discussion I was wondering how a turbocharged gas large displacement engine might run vs a turbodiesel.

I had a 454 gas engine on a service truck and it averaged about 9 mpg....empty or fully loaded.

I imagine that you could regulate the boost to get these engines into the 4 to 500 h.p. range (unless you turn it up to the point of turning the crank blue) and get somewhat similar performance to the high h.p. diesels.

Thoughts??

Brad

My son had a friend with a turbo'd 460 in a '93 Lightning pickup. It was a professionally built 598 cid engine with forged crankshaft, connecting rods, & pistons. Professionally tuned. The turbo was 104 mm inlet, 4 inches. The engine made over 2000 HP at 20 psi boost at 7500 rpm. The guy took the truck to Indianapolis Raceway Park for a test and tune. Truck passed tech, first pass it broke the huge slicks loose at 130 mph and got a little squirrelly. The tech inspector told him to leave and NEVER bring that truck back to race again. Too bad because IRP was only about five miles from his house. He had almost an identical truck with a turbo's 357 Windsor that was almost as fast and tech would let him run that truck.

So Yes, 1000-1200 streetable HP for short duration, 600-700 HP towing with really good aftermarket parts and a good tune. You should be able to get 400-500-600 HP naturally aspirated on 87 octane gas. With more boost and a better tune set on "KILL" there is much more available.

This is something I've wondered about as well with the increased cost and complexity of emissions control systems for diesels. Ford has sure hung their hat on the turbo gas engine concept with their "EcoBoost" line but so far haven't taken it above the 3.5L V-6. I have a 2012 F-150 with this engine and it is impressive; it makes the 7.3L Powerstroke I traded in feel pretty sluggish in comparison when pulling an 8000 lb trailer and gets the same fuel mileage. The direct injection is the thing that makes it practical in that it allows the use of regular 87 octane fuel. It is ironic that the very thing that makes diesel so efficient - high compression pressure and the resulting hot burn - is also what causes the formation of NOx pollutants that are so expensive to deal with. Turbocharged gas engines could get into the same issues but with spark-ignition there is more flexibility on when the fuel is injected and ignited based on current operating conditions which can mitigate the problem. There will always be the fact that diesel fuel contains more energy per gallon than gasoline so even if the efficiency was the same the diesel would still get better fuel mileage. However, in many areas the cost of diesel is 10-15% higher than gasoline so the fuel cost per mile might not be much different. With the current turbo gas engines I doubt that the long-term durability is adequate for heavy, continuous use - probably why Ford doesn't offer an EcoBoost in their larger trucks. However, if the engine was purposely designed and built from the ground up for turbocharging (like all modern diesels are) there are no technical reasons why the durability couldn't be just as good.

you can do it and it will work, to a point, turbocharged gas engines make gobs of horsepower, for example look at the street outlaws tv show,there making unbelievable horsepower and are very fast , but where they cant reach is torque, torque is largely developed by rotating mass, which is always less on a gas engine vs a diesel engine that being said any big block engine from any of the big 3 car makers should be more than capable of pulling anything that needs to be pulled by a pickup truck with a good turbo setup, as to how long it will do it vs a diesel that is unknown

The ecoboost were designed just as you suggest with heavy bottom ends and a bit longer stroke to get the higher torque and be longer lasting. They were designed from the start to be turbo charged or boosted and are not a naturally asperated engine with a turbo hung on for more power as with most previous turbo gas motors. I'm really hoping for one to show up in a larger truck, but ford's new 6.4 v8 is also awesome and my friends gets 14+ mpg doing farm stuff.

Are the eco boost direct injection?

yes they are direct injected and run very good on regular gas, no hi-test required

I really think that turbo with direct injection will displace a lot of diesel applications.

Yes, all the EcoBoost engines have direct injection.

One obvious thing no one seems to ever discuss is transmissions. You can crank butt loads of power through a typical 5 speed manual for racing around town and it will hold up for a while. Then hook it up to a trailer it will go boom in short order if your engine has too much power. Autos and manuals can take the power from gas engines better because they don't crank out the torque at slow rpms. So by the time the power comes on, the load is already moving.

Either way, you don't just build the engine, you have to build the tranny too. My 12 valve is stock but tuned up a little. And that's fine with me, pulls the 15000 # trailer fine and it wont pop transmissions frequently.

No, torque is developed by the mean effective cylinder pressure, area of the pistons and stroke. Weight of rotating mass is only heavier to stand up to the higher torque without breaking and to smooth out the peaks of each power cycle on low rpm engines.

MEP is lower on gas engines due to lower compression rations and lower peak pressures although these are increasing in some of the turbo direct injection gas engines.

I think they did some turboing of those engines in marine applications. I thought at one time gale banks made some kits for gas 454 engines but don't know if they are still involved with that kind of gas performance or not, may be worth a phone call.

The 3.5 Ecoboost shares all of the same dimensions as the no turbo 3.5. The turbo blocks are stronger, the crank, rods, and pistons are forged instead of cast and powdered metal for the non turbo.

The big problem with trying to make a 460 or 454 live with a turbo pulling trailers would be detonation. It's the electronics that makes the Ecoboost work so well without self destructing. Start detonating under boost and it will die a quick painful death.

You would have to go into the engine and lower the static compression to use a turbo to make an appreciable difference.
A belt driven supercharger on the other hand, doesn't need that modification because the manifold pressure increase is linear to engine rpm.

If its a "non-computer controlled" 454, a carb, cam, and headers will have it at 500+ HP really quick.

Scott

What is the 6.4 engine??? I bought a 2015 it still has the 6.2--- Just wondering if I missed something not waiting for 2016

(quoted from post at 10:51:33 01/13/16) What is the 6.4 engine??? I bought a 2015 it still has the 6.2--- Just wondering if I missed something not waiting for 2016

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Could you be more specific in your question? Are you asking how many cubic inches a 6.4L is?