O-ring retainers are certainly not “packaging”. Most cars that used EV6 injectors have a straight through hole in the manifold. The O-ring retainer, does just that, retains the O-ring, preventing it from going into the intake.
Some times people refer to these things are pintile caps. They have a little extra plastic on the bottom to protect the nozzle from carbon build up. All pintile caps are O-ring retainers but not all O-ring retainers are pintile caps.
Aren’t they converted to high Z through the resistor pack?
Let me try to clear up a few things. The o-ring retainers are just that…a retainer. They keep the o-ring from pulling off. Basically a phenolic material, able to withstand engine temps. never seen one globbed or melted. A pintle cap is made of the same type material. They don’t melt but over time will dry out, age and may crack and/or break off. A pintle cap serves two purposes. 1) to hold on the seal. 2) to protect the pintle…hence it is called a cap. The style of injector that uses a pintle cap has a pintle that very slightly protrudes from the bottom end of that style injector. If the pintle is damaged (either sheared off completely or bent) from dropping or any type of mishandling, the injector flow is compromised and the injector requires replacing. There is no fix.
On the EV6 injector shown, there is no pintle extending from the bottom of the injector, so there is no need for a cap. Inside this type injector is either a ball or a disc that pulses up and down on a seat. The parts are inside of the injector and are therefor protected by the injector body itself, so again no pintle cap is necessary, All that is required is the retainer to hold the o-ring in place.
One other correction. A pntle cap does not protect against or prevent carbon build up. See statement above.
SD Faircloth
www.jaguarfuelinjectorservice.com
The short answer is NO. If you exclude diesel and piezo injectors, then there are two types of injectors for our purposes. Peak and hold and saturated. Peak and hold are low ohm. Saturated are high ohm. Each require there own distinct drivers, or electronics. Too much info to type here, but the net is full of data on each type for any inquisitive mind.
SD Faircloth
I have seen the style seal you refer to. With an extra protrusion and I think you are correct that it is the OEM style. I have never used or supplied that type in 14 years of servicing injectors. Never have I had a problem.
SD Faircloth
I replied on JL for everyone to read. SD
In a message dated 1/25/2019 5:42:23 AM Eastern Standard Time, noreply@jag-lovers.com writes:
Thanks for the info @SD_Faircloth
After some more measuring and test fitting today, I think the o-ring retainer can stay. The o-ring seems to seal well enough. I would need to put it under vacuum to be sure but it looks good to me.
Left is injector with O-ring retainer, and right is without.
As for computers, I’m planning to do another DIY job for that. Maybe a fork of Speeduino. I am a computer engineer by trade so it will be fun to make my own computer.
**[quote=“V_Ambrose, post:27, topic:371661, full:true”]
As for computers, I’m planning to do another DIY job for that. Maybe a fork of Speeduino. I am a computer engineer by trade so it will be fun to make my own computer
[/quote]
I think the speeduino could be a bit pressed to deal with all the ignition and injection outputs…if you’re an electrical engineer you’ll be able to decipher the specs…but that was my impression…but I was looking to go full sequential injection so 12 injector drivers…but if you batch fire it could be OK…be interesting to see how you get on. What program is used to “drive” the speeduino …??
Speeduino is made up of two components. The open source ECU software and several open source PCB designs for the ATmega2560 Arduino Mega 2560, ARM M4 Teensy 3.5, etc…
The software currently has support for up to 8 cyl sequential injection or ignition (not both at the same time). This is because of the limitations of the hardware (number of timers and channels) originally used when writing the software (i.e Arduino Mega 2560). It is not a limitation of the software!
Adding 12 cylinder sequential injection support in the software is relatively easy. Its just duplicating a lot of the existing code to support 12 injection events. But you will need more capable hardware.
The Mega2560 is very timer channel limited (i think it only has 12 timer channels). But something like the Teensy 3.5 has 16 channels. You only need 12 channels to run 12 cylinder sequential injection.
Because the speeduino software was written around the Mega2560, it is configured like this;
4 channels for ign, 4 channels for inj, 1 boost, 1 vvt, 1 idle. Using 11 out of the 12 available channels.
In theory you can use 2x Teensy 3.5 and have one dedicated to fuel and one dedicated to ignition. They don’t need to know about each other. They would share the crank and cam position signals and run totally independently. It would be pretty straightforward to do and very cheap. I bet one could build 12 cyl sequential injection and sequential ignition with 2x Teensy 3.5 boards for under $100. Now compare that to the $5k a company like Bosch would want for one of their proprietary systems.
I’d rather have 12 cylinder sequential ignition than sequential injection. So my plan is to add support for 12 cylinder ignition to the Speeduino software, and develop a new PCB with 12x ignition drivers based on the Teensy 3.5. While I’m at it, I could do a PCB with space for 12 injector drivers for future expansion. But this is really just an evenings and weekend type project for me so I think I will first get the car running with something off the shelf like a Megasquirt and then slowly develop my own system.
Yes…that was my recollection …it is ideally for a 4 cylinder engine.
You have to have sequential ignition or your spark ignition engine won’t work but you don’t need sequential injection. The XJS originally fired 6 injectors at a time and ran well.
You can do “wasted spark” which is “sequential batch firing” where two cylinders are ignited at the same time but only one is on a power stroke. There are quite a few coil packs configured like this and they are quite compact and powerful.
How well developed is the software package that drives the speeduino?? The Megasquirt uses Tunerstudio which provides lots of options for engine management…and I suspect developing this would be a pile of work…
I’d say the software is pretty good. Its far more actively developed than Megasquirt. There are a lot of people ready to help and add new features to the software to add new sensors etc…
Speeduino works with Tunerstudio.
Those look cool.
This is my progress so far;
Very slow going since I’m doing everything by hand. I made the brackets so that I would get a tiny bit of crush when tightening up the brackets so the injector is held tightly between the rail and manifold.
I’m trying to document all my work using FreeCAD. I will publish the files when I’m done. I can also look into getting this stuff manufactured in larger quantities (>10) if people were interested. I suspect it would be around $300 for a set of fuel rails and brackets. And look a lot nicer than my hand made jiggery pokery.
Hi Ambrose
Any news ?
