I don't remember seeing a GT350 with a snake on it.

 

On the steering wheel for the 1st generation, and multiple locations on the 67-70 GT350s . . . if that is what you were inferring.

 

Yeah I just don't remember noticing them on the GT350's. And not talking about the Shelby emblem with the cobra backing but the lone snake emblem.

 

Gotcha, thought you probably meant the "coiled" snake. I think '67 GT350 (and GT500) were the first to have it . .

 

Al,

Even though higher compression with DI (Within the limits of existing pump gas) is possible, it doesn’t mean it must be taken advantage of if the cost of doing so is prohibitive (Which the 5.0 Boss engine proves it’s not).

In current port injected engines, depending on the injector location the fuel will wash on the intake valve and valve bowl creating separation and drops of fuel which need to be re-atomized before they will burn which reduces thermal efficiency and increases emissions. The advantage of capitalizing on the latent heat of vaporization of the fuel is also greatly reduced or lost since it’s occurring in the intake/valve bowl area.

One of the overriding advantages of DI is higher thermal efficiency (better fuel economy and power output per measure of fuel). It does this by better atomization fuel and good homogenization of the charge inside the cylinder. In addition to that, the latent heat of vaporization that takes place as the fuel is atomized inside the cylinder cools the cylinder walls, piston head, valves and chamber which is the primary reason higher compression is possible. Reduced emissions is another significant benefit. Of the fuel we’re pumping into the engine, why not burn it all for power rather than pumping some of it back out of the engine as emissions that we have to clean up afterwards with cat’s and EGR?

Just like the last time we discussed points of efficiency and you decried we were (Or at least I was) snipe hunting for “insignificants”, I say every HP left on the table is one worth pursuing. I’d rather have them at my back tires than going to heat the atmosphere needlessly. The racing I’ve done and the engineers I’ve worked with have all taught me you have to turn a lot of stones to find answers. Those unwilling to turn the stones will quickly fall behind the power curve. DI is the next logical step in moving the Otto cycle engine forward in its evolution.

These are good things, where is the valid argument against them? Should we still be using carburetors?

Kind regards,
John

 

YES! Stacks FTW!!

Better atomization, no DI valve damage issues.
.

 

The BMW S65 engine in the outgoing M3 is 12:1 without DI, definitely doable.

Dave

 

Worse atomization for sure when compared to DI but way pretty. I love it but horse and buggy by comparison!

Tell me how DI damages valves please.

John

 

I'll just leave this here.


http://horsepowerkings.com/the-2015-...up-to-1000-hp/

 

There's no liquid fuel drip that's not being burned. The head is over 200 degrees and the intake valve opened creates a vacuum. It's all being burned. You will end up with a carbon build up on the back of the valve due to pressurizing the chamber during normal intake stroke slightly unless forced induction. It's will and it has happened. It's just not needed from what I can see at the present. Will it add a couple horses? Sure. Will it amount to other unforeseen problems down the road? Sure will. Just because the Europeans do it, doesn't mean everyone should. What we have now does a great job and it's proven to withstand time. Reliability trumps 10 hp and 4mpg. Just saying.

 

Just slap the current Super Snake components into the new body. Problem solved.

 

Mazda "Skyactiv" DI motors are also sporting 12:1...and 4-2-1 headers.

 

And a transmission mounted shifter

 

Lol....

 

Evil is correct, also on the 65-66 cars I believe it was on the gas cap as well just not in Tiffany Cobra form.

 

Agreed Al, DI is just too problematic at this time with the gains in performance not worth the trouble with coking on the back side of the valve. The best current solution seems to be a hybrid fuel system consisting of both DI and port injection to periodically clean the back sides of the valves.


GM is using a pretty complex system to scrub crank case gases so we'll see how that turns out in real world use (hopefully it solves the issue for the useful life of the engine (250-300k) as I think such a system would be preferable to having 16 injectors mounted on the engine in the case of a V8.

 

I'm glad someone gets it. It's just not necessary or even worth the R&D right now. I like that ford doesn't just throw new technology at their cars just for the sake of saying they did. Chrysler does this a lot and ends up losing customers due to reliability issues. You don't have to be the technology leader, just the sales leader.

 

I get it too ! I do not see a need to rush to DI. The current fuel injection on Mustang engines works so well with engine mods without the complications of DI. I want something that is easier to modify.