[Jack Blum]

I did the EFI thing back in 1999, now I am thinking about Direct Injection. Anybody know the internals of the 72cc heads? Wondering if I can squeeze a Direct Injector next to the spark plug without hitting a water jacket. The Direct Injector can go in the oily area if that's a possibility. Think Edelbrock would talk to me about a set of one off heads? Anybody have a contact at Edelbrock?


Thanks, Jack.

[steve25]

What's the need for you to have / the big benefit for you to have direct injection?

You can't just wille nille drill a hole in a Intake port and reap the full pluses of direct injection without port velocity study's being done on a flow bench and many times to get the probes to due such where they need to go means scarification of a Mule head!

I do not think that Edelbrock would even entertain the notion of doing a one of if you want my 2 cents as it took the Pontiac community like 8 years just to get them to make us the heads there making now/ as or 1994!

[cgeise]

Steve direct injection does not go in the intake port - JFI -- years ago I talked to Edelbrock about getting a head for experimenting they told me they would sell me a blem for like 50 bucks may be the way to go --

[Tom Vaught]

Jack Blum, Ford had direct injection back in 2011. See article below.
https://www.americantrucks.com/f150-...on-engine.html

I worked in Research on the first ECOBOOST prototype engine several years earlier and continued to work on the boosted engines until I retired. Direct Experience.

For the Le Mans program we needed more hp than the high pressure cam driven injector pump was capable of putting out. 425 HP max. John Clegg (a Pontiac Racer with a ECOBOOST truck) asked me years ago about getting more HP from the engine.

Installing a second cam driven fuel pump on the other head would have cost him $18,000 for the special head plus $$$ for a lot of other required parts. He passed on the deal plus the engine with two systems would make a MAX of 850 hp.

For the Le Mans Race program we needed more fuel, had plenty of air flow capability with two race turbochargers. 1000 HP target HP.

So we designed a head that allowed one Cam Driven fuel pump and added a second fuel system that was a normal RACE "Port Injection" fuel system. That worked well for the 2016 Le Mans race program (which we won).

The point of the above info is direct injection can cause deposits in the intake runner parts. Heads and Intake.

So today Ford runs the new 2020 engines on a combined PORT and DIRECT injection set-up with the PORT injection systems being on most of the time and the direct system acting like the secondary barrels of a 4 barrel carb as far as adding fuel under power.

So if you want deposits in your intake runners over time switch to Port Injection on your Pontiac engine plus expect to have a max of 425 hp based on the best OEM parts out there..

Personally I see no value to doing that. Since I have direct experience with what you are proposing and the dual system was designed for racing initially, I wanted to add my race experience with direct injection parts.

Tom V.

[Half-Inch Stud]

Direct INJ is interesting for Gas 4-Stroke, more interesting for Gas 2-Stroke, and excellent for diesel.

[Tom Vaught]

Originally Posted by Tom Vaught

Jack Blum, I had a typing error and typed Port where it should have been DIRECT as causing deposits in the ports and runners. Fixed it below.


Personally I see no value to doing that. Since I have direct experience with what you are proposing and the dual system was designed for racing initially, I wanted to add my race experience with direct injection parts.

Tom V.

So if you want deposits in your intake runners over time switch to DIRECT Injection on your Pontiac engine plus expect to have a max of 425 hp based on the best OEM parts out there..
TV

[Kevspontiacs@aol.com]

My buddy Dave has a 2020 ZL1 Camaro, he's looking to upgrade some things and found out the stock direct injection fuel system is limited to around 700 HP at the tires. I believe those cars are rated at 650 so not much wiggle room. Iirc The next set of injectors are around $4000 and I'm not sure how much horsepower they will handle.

[Tom Vaught]

The press info I read on the 2020 ZL1 Camaro says 650 Engine hp and then you need to subtract about 12% of the hp before you get the actual tire HP.

Same deal with the 750 HP Mustang. Engine hp not tire hp after the driveline/tire losses.

Tom V.

[Scott65]

This is definitely intriguing, and I hope you'll share the details just for general interest. But I have to wonder "if the juice is worth the squeeze" on this. Not that that should be a barrier to any project!

[Tom Vaught]

The direct injection parts get better and better each year, as the OEMs go down that path but high hp diesel type DI engines have only been explored by a few individuals like Gale Banks. Banks has some interesting videos out there in the last few months.

Tom V.

[Bill Eveland]

it would be interesting to see how you would have some kind of high pressure pump and how you would run it, could easily be over 1000 psi to 1500. The new Fords now have high pressure and low pressure fuel injectors usable based on demand.

[Tom Vaught]

The ECOBOOST high pressure pump is camshaft driven.
The Port Injection pump is in the fuel tank(s).
The Port System is always on and the Direct Injection Pump is activated based on fuel demand. A lot less wear on the high pressure pump by using that strategy. $$$$

Port Injection pumps are cheap.

Tom V.

[81TTA]

...it would be interesting to see how you would have some kind of high pressure pump and how you would run it, could easily be over 1000 psi to 1500...

I believe there are belt-driven fuel pumps that can be used to get the pressure you need. You wouldn't necessarily be constrained to a cam-driven pump.

...Direct INJ is interesting for Gas 4-Stroke...

Depending on your plans for injection timing, you might also want to look into different piston shapes. If you're only injecting while the intake valve is open, you have a lot of design room since air and fuel has an opportunity to mix together.

But, if the plan is to inject with the valves closed or if you're stuck putting the injector in a bad position, you might need a piston top that helps mix/move the fuel in the cylinder. Whether you use a solenoid vs. piezo injector will probably affect this, too. Number of injection events and duration will also come into play.

[taff2]

I would imagine that DI would lose some of the beneficial cooling affect of the fuel vapourising when it's sprayed into the ports in the usual location? DI is probably aimed more at emission control in factory applications.

[mgarblik]

Originally Posted by taff2

I would imagine that DI would lose some of the beneficial cooling affect of the fuel vapourising when it's sprayed into the ports in the usual location? DI is probably aimed more at emission control in factory applications.

Emission improvement was the big driver behind DI as well as a slight improvement in fuel economy. Greatest improvement of course was in cold start/warm-up operation where regular port EFI is dead rich and in open loop, pouring fuel in to compensate for wetting in the port and fuel droplet fall out. DI greatly improves emissions in that situation. The EPA was planning an entire new strategy for emission testing that included cold start/warm-up and extended cold idle time. Advantage in a race situation would be interesting to learn more about.

[Jack Blum]

This is mainly a mental exercise. Don't know if I really want to try it. i like to try different things that other people say "that will never work" and make it work. Thanks all for your input.
Tom V, i would of loved to have had your carrier path.

[Half-Inch Stud]

I would only take interest if the Direct inject allowed any of the following fuels at my whim of avail: Hydrogen gas, propane gas, natural gas, liquid gasoline.

That would be interesting for Street/Strip.

[Tom Vaught]

Originally Posted by Half-Inch Stud

I would only take interest if the Direct inject allowed any of the following fuels at my whim of avail: Hydrogen gas, propane gas, natural gas, liquid gasoline.

That would be interesting for Street/Strip.

Of the gases you have listed above, Hydrogen gas, propane gas, natural gas, liquid gasoline, a couple have been used quite a bit over the years: Natural Gas, and Propane Gas. There are a lot of Variants of "Liquid" gas available at the pumps. Hydrogen Gas is a "Pipe Dream" with today's capability to seal the hydrogen gas for any period of time. Hydrogen Gas migrates thru current design "gas bottles" in a few hours to a week to ten days in the best storage systems.

Spent several years working with the proposal to run Hydrogen Gas in Ford Vehicles as well as High Altitude "observation" platforms.

Here is a couple of pictures of platforms that were tested using Hydrogen Gas as the propulsion fluid. Hydrogen Airport Shuttle Bus, Performance Truck, and and a link to the Phantom Eye "Observation" Platform.

1) https://www.boeing.com/defense/phantom-eye/

2) Airport Shuttle Bus Photo

3) Shuttle Bus Engine (Hydrogen)

4) Ford TRI-FLEX Engine 3 different fuel capability.

Tom V.

Jesse James, the TV Biker/Fabricator THOUGHT he was going to weld up some Hydrogen Fuel Tanks and run a engine on Hydrogen. The best technology in Hydrogen Storage at the time only gave the Hydrogen Gas 4 days containment before it completely escaped the container. That is why the Phantom Eye Aircraft could only stay 'on station' for 4 days
in the middle east.

So you need to do a bit more reading HIS. Actual Engineering EXPERIENCE goes a long way with most projects.

Doing Direct Injection Properly takes some real effort, IME. (E = Experience)



Tom V.

[Scarebird]

Originally Posted by mgarblik

Emission improvement was the big driver behind DI as well as a slight improvement in fuel economy...

I would disagree with that.

My 2016 5.3 GMC has DI. It gets 17mpg around town, 22-25 on the highway.
380 horsepower. This is far superior to the 2003 4.3 I had previously; double the HP and better mileage - with a worse cD truck that is 800 pounds heavier.

That said, 5 of the 8 injectors replaced under warranty with less than 10k miles.

[Half-Inch Stud]

Tom, I store my htdrogen as water. Hydrogen gas generated on-demand is where i'm at.