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Just Some Dude in Jersey
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Keep in mind that the oem FI was solely focussed on economy and low emissions, with very little consideration of power. When I was configuring the 2.4 motronic FI on my 2.4, we tried out an aftermarket throttle body that was the equivalent size to the larger throttle on a 6 cylinder 3.0 liter Opel FI system. The 2.4 computer was too dumb to handle the much larger air flow, but at about mid-throttle it had rev response that was super fast, like you are trying to achieve. With a more adaptable computer, that could deal with the higher air flow, we could have made it work and gotten a faster rev'ing engine.

So, what I'm saying is: Don't get locked into the stock throttle size. I don't know how one calculates the maximum size throttle that an engine can handle, but going big on the throttle is something to consider. I'm sure there are detriments to going too big or too small.
 

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Just Some Dude in Jersey
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The bump might be there to add turbulence near the injector to improve air/fuel mixing or to push the airflow towards the offset injector to improve air/fuel mixing.

The injector offset may be to better aim the spray of fuel in the direction that the air flows through head. The ports in the head aren't a straight shot to the valve/cylinder, they each bend right or left towards the valve.
 

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Just Some Dude in Jersey
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The throttle body in your pic is the one we used. We ended up not using it because the stock Motronic couldn't seem to handle it at low rpms, only at mid to hi. We also noticed that it had vacuum leaks at the throttle pivot holes and decided that it was too loosely machined. Basically: Cheap, Shiny, Crap. We also needed to add a 3/4"-1" spacer to clear things. It's the same size as the Opel 3.0 liter throttle body, but you can tell right away with one of those in your hand that it was machined to MUCH tighter tolerances. But the hole pattern is off a bit and won't directly bolt on to the 2.0-2.4 manifolds. Some modification needed.
 

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Just Some Dude in Jersey
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Looking good! You seem to have done the necessary mods. How is your clearance between the manifold and the cowling? I'm using a 2.2 manifold and I had to bend the drainage channel of the cowling up about 1/4".
 

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Just Some Dude in Jersey
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Extra wires and customizing seem to be part of the game when modding an old analog car to FI. My present car has a 1990 Motronic system and I had to eliminate half the wires. There were a lot OBD1 diagnostic wires, plus ones for controlling a modern electronically controlled auto tranny, anti-lock brakes, etc., that all had to go. If I had decided to run my oem system with an aftermarket controller, I would probably have had to cut off many, if not all, the plugs and graft them onto the new system's wiring harness.

Consider mounting your ECU and extra wiring in the passenger side footwell, which would require cutting a decent size hole in the firewall on that side. I'm customized and don't have the heater there anymore, so I have plenty of room to mount all that stuff behind the dash.

I understand your fascination with the latest, coolest, injectors, but, remember: You're rigging an old, weird, car for FI and you're making your own unproven manifold design that may or may not have the optimum injector positioning and general flow of air. Plus, you're thinking of throwing a turbo into the mix? You've got all sorts of variables going on and almost all of them are unproven. The older, larger, injectors were used for decades and nobody complained, I hardly think that the latest gee-whiz injectors would make any noticable difference. The oem FI had the injectors squirt right at the head ports, your concept has them a few inches farther away, Holley Snipers have them all the way at the beginning of the line before the throttle plates, my system will have them just after the throttle plates, carbs introduce the fuel before the throttle plates and various carbs set ups are near and far from the engine, and they all seem to work just fine.

I have also bought the Terminator X system and am awaiting it's arrival. I probably won't get to installing it until the Fall/Winter. Using only 2 injectors and 2 throttle bodies, I have concluded that I need to configure the ECU to run like a 2 barrel Holley Sniper, which have 2 injectors. I contacted Holley late last week to ask how to configure the system to run the spark and injection like a 2-barrel Holley Sniper. They said to wait 3-4 days for a response and I'm still waiting. I'll also have lots of extra injector plugs, six of them, that I'll have to bundle up out of the way or chop off. Are there knock sensors also? I don't know, that will be another hurdle to cross. Do I need or want knock sensors? Can I find those sensors and adapt them to my car? Don't know. But figuring all that stuff out is half the fun. 😀
 

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Just Some Dude in Jersey
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I agree that you don't want to grab any old injectors you find laying around. My comment was in regards to only focussing on using the latest, state of the art, short ones. I would go with whatever the Terminator X system recommends. Do they only recommend the latest, coolest, injectors? Or do they suggest any injector within a certain flow rate and other factors?
 

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Just Some Dude in Jersey
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17,324 Posts
We(me and Charles Goin) had custom thermo housings made. I have THREE thermostats. I use a different heater outlet at the back of the block near the oil pressure sender(which I relocated up front near the oil pump).

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Just Some Dude in Jersey
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Why make your own when you can just buy one that relocates the sensor to the fuel pump vicinity, as the pictures I posted show? Most of this modification stuff has already been done by many people for decades who are a lot smarter than most of us and they have been race proven to work. And, what's wrong with the oem design of the trigger wheel and stock mounted sensor below it?
 

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Just Some Dude in Jersey
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This site is not the place to find weird European parts. 99% of the Euro guys are on the Facebook groups.

I won't get that CPS bracket until Charlie delivers my engine and that will be a month or two....or three...

I could make a tracing of it for you. I suspect that it is very high precision in exactly where it holds the sensor, like the oem one is. 1/16" off and it won't work. Build adjustability into your design if you can.
 

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Just Some Dude in Jersey
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Once again I will suggest going with the Edelbrock returnless fuel pump system.
1) The surge tank is built into the system
2) The adjustable regulator is built into the pump, the filter just goes inline between the pump and the rail
3) You dead end the fuel rail, no need to run a return line to the tank
4) The high pressure pump only needs to pressurize about 2' of fuel line and the rail itself, no need for it to pump gallons and gallons in a big circle back to your tank and back to the fuel rail and back to your tank and........etc.
5) A low pressure pump does the grunt work of bringing the fuel forward from the tank
6) The high pressure pump is emersed in fuel, so it is constantly cooled
7) The system can handle 700hp worth of fuel consumption
8) You mount the main pump and surge tank combo somewhere in your engine compartment or, in our GT's, in front of the radiator somewhere for easy accessibility and, if in front of the radiator, additional cooling
9) It is quieter than any electric fuel pump, carb or FI, that I have ever experienced in my modern cars or the one Opel I have it on at the moment
10) No messing around with your 50 year old tank and running a return fuel line inside your passenger compartment. You do run a vent return line to one of the tank's vent outlets

Why would you get vapor lock in an FI system? The fuel doesn't sit in a reservoir, where it can get baked to the boiling point by exhaust heat, like our carb systems do. If you route your fuel line in front of the radiator, then to the carb or FI system, then it's not subject to any heat. Maybe, only a big fuel pump mounted at the back of your car shoving all the gas in your car in a big circle, non-stop, would heat up your fuel enough to get vapor lock.

I've worked in industry my whole life and I have never seen any hydraulic pumping system that requires a large amount of fluid to be pumped in a giant circle, non-stop, to supply a tiny amount of usage. The water in your house doesn't work that way. Hydraulics only activate the pump when needed. Air conditioners only pump their fluid when the compressor turns on. The list goes on. I can't think of any fluid system that needs to supply a very small amount of fluid to an outlet that works the way old school car fuel pumps work.

My new car will be getting another Edelbrock system and this time I will try mounting it somewhere in front of the radiator, maybe on the horn rail or maybe below or next to the master cylinder.
 

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Just Some Dude in Jersey
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The required low pressure part of the kit isn't included, because many people choose to continue using their oem or aftermarket low pressure carb pumps. You can continue to use whatever low pressure pump your car has, mechanical or electric, to bring the fuel forward to the high pressure pump. Edelbrock sells a very nice, quiet, rotary, low pressure red pump, if you want to install it. The low pressure pump fills up the reservoir/surge tank, which is next to the high pressure pump. The overflow fills the high pressure pump side. When both are filled, a float stops the fuel flow from the low pressure pump.
 

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Just Some Dude in Jersey
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Last part needed is on the way.

Although I don't actually need it, the alternate mounting location custom crank position sensor holder/bracket is on the way. Actually 2 of them, one from Charlie and one coming from the guy in Europe who made them, Anders Tjernström. It's his last one and I don't think he's going to make any more. I'll be putting both of them on my cars, but I would like to see if I could get someone to reproduce them before I install the last one. They weren't expensive, just $50 each. They mount to the oem fuel pump location at the bottom of the distributor housing. If you have a 2.4 timing cover, the center hole for the fuel pump plunger is undrilled and basically blocked off, but the 2 pump mounting bolt holes should still be there and threaded, so it should bolt right onto that location. If you have a 1.9/2.0 and possibly a 2.2 cover, this bracket replaces the fuel pump block off plate. It is made to mount a Bosch crank position sensor to read the 60-2 timing wheel on 2.4 or other Opel engines that use that timing gear. It's benefit is that it relocates the CPS sensor from the 7:00 position, which is directly over a GT's front suspension crossmember with only a 1/4" gap, to the more accessible and safer 2:00 position. It also eliminates the need to try to find the hard to get 2.4 oil pump covers that have the oem 7:00 position CPS holder molded into them. It seems to also have a carve out on the side to help dodge the fan belt.

Even though I have the 7:00 position 2.4 oem oil pump cover bracket and sensor, I want to use one of these holders to relocate the oem sensor away from the crossmember and the tight clearance there. It's almost impossible to remove the oem sensor in the 7:00 position without jacking the engine up tight against the tunnel, with an auto tranny, or removing the oil pump cover. It might be easier with a stick tranny. It's also possible for the sensor to get damaged if motor mounts collapse or you hit a really bad speed bump. It's also a cool gizmo that almost no one has. It's mounting method, location, and design might also give inspiration for a bracket design for those who want to use an alternate style of timing wheel than the Opel 60-2 one.

I'll entertain the thought of lending out my spare for a short time to someone who could scan or measure it and reproduce it in some fashion. These are pics from Charlie, I'll take more detailed pics and maybe measurements when I get it in a few days.

Bumper Wood Tool Automotive exterior Automotive design
Photograph White Wood Gas Auto part
 

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Just Some Dude in Jersey
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17,324 Posts
I do really like @The Scifi Guy’s crank position sensor solution. If I had one, I would have installed it in a heart beat, but since I don’t and am a fabricator, I sort of go with what I know, and what is cheap and fun.

I designed and 3D CAD model 3D printed a model out of ABS for test fitting.
View attachment 447327

Cast it out of aluminum (I hadn’t melted metal in a while and was keen to fire up the trash can foundry). I have an old alloy wheel I have been cutting up and metaling down, so whole project costs very little.
View attachment 447330 View attachment 447329
cleaned up the rough casting. It was rough, as I was in a hurry and did not take time to degas the aluminum, so there is porosity in the ipper
View attachment 447332
a little bit of time drilling and boring holes and talking the sensor mount bolt hole.
View attachment 447333
and here is is installed. I will have to check and verify a good pulse signal. I hope I can find a way to do that with my multimeter.
View attachment 447335
i think the spec on the air gap is 0.8 mm +/- 0.3 mm. So that is roughly 0.031” which is roughly 1/32”. For that reason, I cast The sensor mounting plate on the thick side. If the gap is too big, I will just machine it down a bit.
Uhhh......I ran into a BIG problem with that bracket and couldn't install it. The top of the sensor hit the lower alternator bracket and I couldn't even come close to being able to bolt it on. Charlie thinks that maybe it was designed for the Opel 6 cylinder engines and maybe they have a more minimal lower alternator bracket. And looking at the whole area, It seems that the bracket could have been designed to mount in the, say, 4:00 position, instead of the approximately 2:00 position, and there would have been plenty of clearance.

Now, it I or you used an F-bracket from the auto store, it would probably fit just fine, but those brackets don't have any shock/vibration dampeners and they break easy. I still had my Motronic sensor in place, so I decided to just use that.
 

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Just Some Dude in Jersey
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Wow, that's great!

Are you heating whatever you're using for the aluminum you're melting down for a long time and skimming off the slag? What sort of sand is that that you're using? Do you reuse it? Is there a certain critical moisture content in the grit and too much can cause steam and bubbling? I'm thinking a finer grit and also don't reuse waste from previous castings because they may have some grit in them that might cause pores, plus long cooking or maybe a higher temp before pouring.

When I made my high school stuff, I brought in broken high end bicycle parts made by Campagnolo, thinking it would make really great casting material. But the teacher had to skim off a lot of slag that didn't melt. I guess there was all sorts of Magnesium and other metals in those bike parts.
 

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Just Some Dude in Jersey
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17,324 Posts
I put my remote one in the air box I made for my TB's. The seller tells me that the IACV is really only for fine tuning the idle and should only have a duty cycle of 5-10%. The rest of the air should come via the throttle. You have to calibrate your fully closed and open throttle voltage readings, then start the car and observe the IACV duty cycle. If it's above 10% you then start turning your idle adjustment screw until you are at 5-10%. You have now messed up the closed throttle calibration, so you need to recalibrate it again. Start the engine, check the duty cycle WHEN THE ENGINE IS FULLY WARMED UP, adjust as necessary for 5-10%, shut off and recalibrate the throttle again.
 
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