Generation IV External Engine - Direct Injection What's on your mind??

GM stated that the new Gen V engines will come out with Direct Injection. Sounds like pretty good technology that has been around for a little while. I'm wondering what if any it will carry over into the performance market for high HP builds. Sure sounds promising. What is everyone's thoughts? :usa:

732 veiws and nobody has any thoughts or input on this? Wow, slow days on Tech...:bang:

as long as the fuel system is up to the task it will be fine.

Operating psi is to the moon....75 to 200 bar. AFR's in the econo mode at 65:1, performance range at 25:1. Op volts as hi as 90.

Operating psi is to the moon....75 to 200 bar. AFR's in the econo mode at 65:1, performance range at 25:1. Op volts as hi as 90.

So with all this will we be benefiting at all?

We'll have to benefit from it. Once everyone realizes the benefits, you won't want anything else. This isn't a new technology by any means. Diesels have been this way almost forever. This is how they run such high combustion #'s, dont require spark plugs, and can burn a fuel that is less refined.

I honestly dont know why we haven't implemented this into the gasoline world long ago. I'm excited about it. I look for the OEM's to come out with some crate engines that offer DI, similar to what GM has done with the E-rod's. Once that happens I expect the aftermarket to be all over it. It will require some revamping of our factory fuel systems but it will be worth it.

We'll have to benefit from it. Once everyone realizes the benefits, you won't want anything else. This isn't a new technology by any means. Diesels have been this way almost forever. This is how they run such high combustion #'s, dont require spark plugs, and can burn a fuel that is less refined.

I honestly dont know why we haven't implemented this into the gasoline world long ago. I'm excited about it. I look for the OEM's to come out with some crate engines that offer DI, similar to what GM has done with the E-rod's. Once that happens I expect the aftermarket to be all over it. It will require some revamping of our factory fuel systems but it will be worth it.

I agree 100%. If it takes a little extra money to gain me a little more HP, drivability, and maybe even a little more MPG i'm all for it :chug:

I went from gen 3 motor to a gen 4. Better believe I'll be all over gen 5.

If I recall correctly the Cadillac V6 picked up 50 horsepower a couple of years ago when they went to direct injection. I am surprised that direct injection has not been engineered into the GM performance V8s yet.

If I recall correctly the Cadillac V6 picked up 50 horsepower a couple of years ago when they went to direct injection. I am surprised that direct injection has not been engineered into the GM performance V8s yet.

I agree. I hope it's something we can retrofit to our Fast intake or it will be more $$ right out the window again!

I agree. I hope it's something we can retrofit to our Fast intake or it will be more $$ right out the window again!

I hope your kidding...DI requires a different cylinder head design with a boss for the fuel injector as well as the spark plug. Fuel is sprayed....directly....into the cylinder.

I agree. I hope it's something we can retrofit to our Fast intake or it will be more $$ right out the window again!

I hope your kidding...DI requires a different cylinder head design with a boss for the fuel injector as well as the spark plug. Fuel is sprayed....directly....into the cylinder.

Yeah, you're going to need a completely new top end from cylinder heads to intake manifold. The whole point of DI is that the injector sits in the head and not in the intake track anymore...so retrofitting DI to current engines will have nothing to do with the intake manifold. At the least it would be plugging up the existing injector holes as they will be of no use anymore and you don't want open holes in your manifold.

Yeah, you're going to need a completely new top end from cylinder heads to intake manifold. The whole point of DI is that the injector sits in the head and not in the intake track anymore...so retrofitting DI to current engines will have nothing to do with the intake manifold. At the least it would be plugging up the existing injector holes as they will be of no use anymore and you don't want open holes in your manifold.

Hahahaha, man we needa sarcasm/joke button in this place :barf:

With all the dumb people/posts in this forum, one can never be to careful with seemingly idiotic posts. It's better to be safe than sorry, so when I am faced with such posts I tend to just go along as if the post was real and not sarcastic.

With all the dumb people/posts in this forum, one can never be to careful with seemingly idiotic posts. It's better to be safe than sorry, so when I am faced with such posts I tend to just go along as if the post was real and not sarcastic.

Oh i understand, guy never knows his/her machanical knowledge from behind the keybord. I assure you it's not the case here :usa:

I have been looking for a sarcasm font for years!

Direct injection brings a bunch of problems to the table. Go check out the Audi RS4 forums for the power robbing valve debris build up that happens because there is no cleaning fuel wash across the back of the intake valve head. This is now happening to the GM V6 motors, VW DI motors, Lexus DI motors and many others.

Direct injection brings a bunch of problems to the table. Go check out the Audi RS4 forums for the power robbing valve debris build up that happens because there is no cleaning fuel wash across the back of the intake valve head. This is now happening to the GM V6 motors, VW DI motors, Lexus DI motors and many others.

As a minimum, your going to have to swap over to a vented catch can and not run any vaccum or vent to the intake from the crank case. The maybe add a methanol injection or water/meth and retune it so you can keep it clean inside.

Direct injection brings a bunch of problems to the table. Go check out the Audi RS4 forums for the power robbing valve debris build up that happens because there is no cleaning fuel wash across the back of the intake valve head. This is now happening to the GM V6 motors, VW DI motors, Lexus DI motors and many others.

Issues reeling their ugly heads that soon in the game means it will be quite sometime for it is perfected

the power robbing valve debris build up that happens because there is no cleaning fuel wash across the back of the intake valve head.

If you've every seen valves in most port injection engines you'd know that no valve is ever spotless. Fuel can be dirty too, and it can gum up on the valve just as much as oil.

As mentioned, a simple solution would be for a catch can to be installed or the PCV system to be vented out in the air as apposed to pulled by the vacuum back in the manifold.

Doesnt venting out in the air cause issues of oil loss like the big long nasty Thread that comes up on here about PVC Routing Debate? lol

Valve debris build up is a result of gasoline boiling on hot backside of intake valve, how is a catch can going to solve this problem. FYI the Audi RS4 already has a very exotic air/oil seperator circuit in its crankcase ventallation system. Oil vapors are not the cause of this problem.

Valve debris build up is a result of gasoline boiling on hot backside of intake valve, how is a catch can going to solve this problem. FYI the Audi RS4 already has a very exotic air/oil seperator circuit in its crankcase ventallation system. Oil vapors are not the cause of this problem.

If gasoline is being injected in front of the intake valve into a small pocket just before ignition, how is it getting to the back side of the valve. What you describe sounds like something that would be on a port injected engine.

It's called REVERSION and happens during valve overlap between the exhaust cycle and intake cycle when both valves are open, you get some travel of the fuel air mixture from the combustion chamber to the intake port. On high performance motors with long duration cams, you can see the effects of reversion into the intake manifold. Some of this can be cancelled out with injector timing and runner tuning but, like I said on a high performance motor like the B7 RS4 this build up is a major problem in the long term. For a motor with short valve timing it isn't as great a problem, for my Duramax truck it isn't either but for gasoline fuelled cars, this problem hasn't been fully addressed.

i believe gm did a DI L92 test motor, modified the heads for it and everything. apparently it made nice lot of power. was an article on here somewhere

I think direct injection for gasoline is fantastic, I can't wait until gen 5 and when aftermarket parts become a little more mainstream. Power potential for DI is massive in stock form, but when the fuel system capacity is exceeded, expect those modifications to dwarf all other vehicle costs...

Also worth a mention, PCV is going to need a complete redesign. I've never seen Audi's version, but I'm sure its exotic for a reason. Someone correct me if I am wrong, but if new-generation DI gas engines are anything like a diesel, they won't have a throttle body and therefore no vacuum... There would need to be some sort of vacuum pump to pull fresh air through the engine.

The valve debris problem is an interesting one...looking forward to progress on a fix for that.

From the articles I've seen, the DI pistons are drastically different than what normal pistons look like. I am sure when GM does interdue the DI V8, they will have to use torque management to keep their trannys (& rest of the drivetrain) under warranty.

Operating psi is to the moon....75 to 200 bar. AFR's in the econo mode at 65:1, performance range at 25:1. Op volts as hi as 90.

I think you may be confusing Common Rail Diesel Fuel Injection.

The DI system used by Corvette Racing three years ago operated in the 1250 psi range.

DI is given credit for 10% to 15% increase in power. 91 octane production cars from Europe are running 12.5 to 12.8:1 compression ratio.

I believe that in two to four years we will see aftermarket heads which have incorporated OEM Direct Injectors. Packaging and driving a pump will be interesting.

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Like posted above it will be $$$ to modify. The oems are waiting on electrical operated valve tech(solenoid) to fully go this route. Imop. We shall see. The Gen 5 V6 Camaro is already DI. They have N20 kits out for it. So the aftermarket is embracing it some.