Gdi plus pfi injection

[Skylarking]

Isn't it interesting that it looks like GM have deactivated the AFM option on the LT4 motors as found in the 2018 Camaro even though they do have the correct components in the engine.

AFM is not used in aftermarket LT1 and LT4 crate engines. I believe it is well and truely functioning in vehicles fitted with such engines from factory.

 

[lmoengnr]

So all that VVT and AFM is possible for the LS3?

Yeah, its called an L99.

The LT5 has direct injection and PFI in a 'staged' set up to cope with 755HP.

 

[Immortality]

AFM is not used in aftermarket LT1 and LT4 crate engines. I believe it is well and truely functioning in vehicles fitted with such engines from factory.

You'd think so and yet a US tuner confirmed in fact it wasn't on his 2018 Camaro with LT4.

 

[Hq King]

@Hq King your question should really be structured around what you want to achieve as there may be better alternatives.

Direct injection is simply a more expensive option and my guess is that manufacturers would use it due to its tighter fueling control allowing compliance with pollution laws (with the added benefit of reduced fuel consumption). Such systems would be used where port injection would otherwise not meet such pollution laws.

Ford uses port and direct injection in their new mustang as does GM in the new US Cameron SS but not sure which engine the older aussie (HSV convert) Cameron has in it.

Cost wise, who knows how much it would be to retrofit port and direct injection with VVT and AFM to an old LS3. But GM has done the work and it’s called an LT1.

My guess is that a LT1 crate engine would be a better bet, though getting it to play well with the VF ECU, TCM, BCM, etc could be somewhat interesting.

If you go the LT1 crate route, i doubt you’d have much change from $20k (ok I admit the figures are pulled out from a dark place). But on the www, I have seen LT1 crate engine @ $10k and you’d still need LT1 ECU + clutch bits + bellhousing to match your gearbox + other bits you may not be able to pinch from your LS3 and probably some custom fabrication. So it will quickly mount up - for around a 340kw engine? Does it make sense?

May be, buy the next Camaro with its standard LT1 when it finally comes out in NZed Or put a cam, headers, etc in your LS3 if you are chasing power If you want economy, well that’s a bit of an oxymoron when used in a sentence with V8

Ok guys to be honest I was just wondering about the concept some late model euro cars seem to be going away from direct injection and going to port and direct injection for reasons I am not real sure ?But could be carbon build up of valves probably some power gains and maybe fuel economy again I am not sure maybe just another dodacky that costs lots and does very little

 

[FPFQ_king]

Ok guys to be honest I was just wondering about the concept some late model euro cars seem to be going away from direct injection and going to port and direct injection for reasons I am not real sure ?But could be carbon build up of valves probably some power gains and maybe fuel economy again I am not sure maybe just another dodacky that costs lots and does very little

DI is a waste if money for sure, AFM will cost too much to retrofit to an LS3, however VVT is possibly the best upgrade you can do for performance, efficiency, consumption, and emissions proofing your build.

 

[Immortality]

Have a look at what Keonigsegg are doing with their pneumatic valve design, better fuel efficiency and more power than DI using port injection with less emissions to boot.

 

[Skylarking]

You'd think so and yet a US tuner confirmed in fact it wasn't on his 2018 Camaro with LT4.

Hm, odd.

Just had another look and it is advertised as a feature in 2018 Comaro with both LT1 and LT4 V8s but seems to not be listed as a feature in 2019 model. Go figure...

 

[FPFQ_king]

Have a look at what Keonigsegg are doing with their pneumatic valve design, better fuel efficiency and more power than DI using port injection with less emissions to boot.

the Regera uses hybrid stall and TTV8 on Miller cycle (Prius VVT supercharged) to get instant torque and miserly consumption. Basically always in top gear.
Guys here in AU have done Atkinson (Prius VVT N/A) and custom tuned trans (first gear bypass and loosened TCC) on the GenIV with stunning performance and consumption results.

 

[Skylarking]

Have a look at what Keonigsegg are doing with their pneumatic valve design, better fuel efficiency and more power than DI using port injection with less emissions to boot.

Motor manufacturers have been dragged kicking and screaming into the 21st century as laws push them to pull tech off the shelf’s and put them into vehicles.

Maybe in another 10 years, the ICE may be much more efficient than today BUT it will all be all too late as it’s almost certain that electric motors and battery tech will take hold in less time than that

As for desmodromic valves, pneumatic valves and lots of other tech, they are nothing new but simply not economical in volume. Stupidly priced supercars are the exception and I love to look at them but for example one of the Ferrari models had gold plated titanium exhaust which does nothing for performance when dribbling along the road stuck in peak hour traffic atleast gold plated titanium exhaust look expensive and were visible to others in traffic

 

[lmoengnr]

Cant see too many benefits of the Atkinson cycle on an engine with a single cam core...
Works really well when you can vary both cams, or even just one and lock the other.