jumbo torque 351 W turbo concept

[Huntersbo]

Just an idea that I have never seen propesed!
I have a '82 f-150 and I was thinking it is a good set up needing a little tweaking. I get 6-11 mpg running from 1300-3000 rpm and a 50 mph cruise at 2400 rpm. I was thinking that max torqueat 2300 rpm is too high and I do not care that it makes 200 hp at 3300 rpm, it is only 140 or 160 at 2800 rpm. I was thinking of runing a 230 duturation of valve timing seat to seat with 6:1 compression to runon 87 octane. I would aim to get the peak torque around 1600-1900 rpm and I would not rev past 2800 rpm. I would think to add a turbo charger with the right flow chairacteristics to keep torque down low. Mabe I could get 180 hp at 2500 rpm adn 450 -500 tq at 1700 rpm.

I need to fix this truck before I get to my Scout that will be diesel. I will not go diesel on the truck becasue it is not worth it to me- just a family tow rig to used occassionally after my scout is built.

 

[spencnaz]

Your compression ratio is way too low, you would be hard pressed to even start the engine with it that low.

When the engine is at peak torque, your fuel economy will be highest. Turbos are not economy devices in gasoline engines as they are forcing more fuel and more air to make more power.

Keep the compression ratio at about 9:1 and get a cam with a torque curve in the 1500 to 4000 rpm range. Remember too that your rear end ratio makes a big diff on your fuel economy. NO way you're going to get 450 ft/lbs of torque that low in a gasoline engine of that displacement, the cylinder pressure will not generate that.