B20 Fuel Injection Questions

B20 Fuel Injection Questions

Updated again!
As I said below in one of the posts, I was going to finish up the project and see how well or horribly it would work.
Well, the data is in and it's not good!
As predicted, the fuel distribution is compromised by the firing order.


Cylinders 1 & 4 look about right, but 2 & 3 are running really rich.
It seems pretty obvious to me that this is an unworkable method.

But, damn it, I'm tenacious, I have two more possible methods up my sleeve. I have a funky home made manifold that attaches to the stock intake manifold that mounts a Ford Motorcraft carb. The carb is crap, so I opened up the annular rings and mounted two injectors in the carb. This basically makes it a throttle body set up Stay tuned and I'll see how that works out.
Also in the planning stages is something like the set up I have now but it will mount between the manifold and the head with an injector bung for each cylinder. Probably where I should have started, but I'm just doing all of this for fun and a not too expensive education.

He that is taught only by himself has a fool for a master.
H.S. Thompson

Update!
I've done more research on this project and have found a couple of things that at=re of interest

Fuel pump/sump etc
Edelbrock kit that has everything needed

https://www.google.com/search?q=Ede...me&ie=UTF-8#kpvalbx=_ukCwXpHxFNL7-gTSiraQAg36

A very good article on siamese port injection:
https://www.starchak.ca/efi/siamese.htm


I'm gearing up to install Megasquirt in my B20 swapped '58 Duett.

1. On a previous project I bought one of the super cheap fuel pressure regulators, of course it crapped out within a week. They sent me a replacement that lasted about 2 hours. In both cases the diaphragm was the problem. The FPR looks like a direct rip off of the Aeromotive FPR (13129 or similar).
The question - will the Aeromotive rebuild kit fit the cheepo-Chinabay part?

2. On the Duett there is nowhere to install a swirl tank. The fuel tank is quite deep and I am going to use the stock pick-up.
The question – Does the stock mechanical pump have enough capacity to serve as a pre-pump for the fuel injection pump?

3. Tool wise, I'm going to use plug connectors which have pins that require crimping in two places, the bare end and on the insulated part of the wire for security.
The question – Where is this type of crimper available?

I'm doing this project with the requirement that it can be reverted back to carbs easily and without modifications that can't be undone.

Thanks for your answers, expertise and suggestions
Stay healthy!
TR Conn

Pump should work as a prepump as long as hp is similar

1) I have no idea. But, perhaps now would be a good time to source a legit non-china FPR?

3) I have several sets of crimpers costing $80 and up. But, one set is most likely sufficient. If you want to go cheap this might be what you want:
https://www.amazon.com/GM-Delphi-We...keywords=delphi+crimper&qid=1585107704&sr=8-7
as a bonus, they are only $11.99 more than the typical T-Bricker motto of $14.99 shipped!

For the FPR, of course you are right. I'm just hoping for a little serendipity.

The engine is stock. Using the fuel pump will simplify things a lot.

This is the type of crimping I need to do.
Will that one do it?

1. Probably not. I would buy the summitracing knockoff, that one is rebuildable.

2. Nope, tried that. Unless you’re using a surge tank under the hood, it will starve. Carbs have bowls for a few reasons, this is one.

3. The E style crimpers can be found at most auto parts stores. Use one size on the wire and the next one up for insulation.

Move the battery to the trunk and you can put a swirl pot where the battery was.

No matter which way you do it you will need a return line to the tank.
This is to purge air from the fuel and cool the fuel rail and injectors.
Do this right and avoid problems. Especially if you plan to add boost, You could wind up replacing everything.

Using the stock diaphragm pump to fill a swirl pot will work but you will have to crank for fuel. (not ideal)
Better to have a lift/feed pump in the tank.
You cannot use the diaphragm pump in series with the HP injection pump because it will not flow enough volume for the return fuel.

The stock Volvo regulator works just fine, there area also some Bosch units that lend themselves to universal use.
What intake manifold will you be using? The fuel rail and regulator that comes with it will likely be fine.
I'd recommend avoiding Low Impedance injectors if at all possible.
Using as many (commonly available) OEM parts as possible/practical will save you headaches.

This is in a B20 in a Duett.
There is no trunk, under the car the space under the back seat is occupied with the fuel tank and the muffler. The pump and filter could be mounted next to the frame rail, but still no space for a swirl tank. Perhaps a high capacity low pressure electric pump could supply enough fuel???
I've already plumbed for the return line, just need to figure where the line goes.
The stock regulator (D-Jet) could be used, but it has no vacuum port. I could use one from a Nissan 280Z but it isn't adjustable. The pressure will probably have to be cranked up to keep the pulse width reasonable. I'm going to use 2 36 lb injectors in a throttle body set up using the SU carbs.
I figure if a B230 is happy with 4 17 lb injectors then a B20 can work with 2 36 lbs.
Lots to figure out, lots of time on my hands at this point.


Thanks for the input, lots of problem solving ahead.
TR Conn

I'm in the process of swapping to a custom rail and such on the 140. Take a look at the Radium fuel pressure regulators. They have one that has all -6 fittings, and runs a run of the mill, easily replaceable VW style Bosch FPR. Ran me $129 delivered including the FPR.

I did run the 280 reg for a long time, made a big difference over the stock one without the vacuum. I didn't have any real issues setting it up, but the pressure was a bit lower than I'd like.

First off, those look like Bosch injectors from the D jet on the B20E /F / B30E (model number being 280 150 036?). If so, corrected to 43.5 psi they flow about 57.6 lb/hr. I use the Nissan 280 Z regulator which runs at 38 psi and I have tested out the flow to be 515 ml/min @ 38 psi. Offset at 14 volts operating is around 0.15 msec. Running gasoline with a maximum duty cycle of 80 % two Bosch 036 injectors running at 38 psi should work just fine (if they are clean) on a stock B20. Four 036 injectors on the B20E were grossly oversized for the engine output, even considering that the first B20E ran at 28 psi fuel pressure.

The Bosch 036 injectors are a low Z injector. They work just fine with an external 6 ohm 50W current limiting resistor (get them from Digi Key - Dale is a common brand). Do not try to make that PW option in MS for use with low Z injectors work. Too much agony.

From personal experience I would stay away from the Aeromotive regulators running pressures below 43.5 psi and unless you run large return lines (3/8" seems the absolute minimum). I had bad experience with trying to maintain stable fuel pressure. The Nissan 280 Z FPR provides stable fuel pressure on my B20E and operates just fine with the stock 5/16" supply and return line on my 142E with B20E.

You can make the original style D jet fuel pressure regulator work with Megasquirt. The uncompensated D jet regulator results in the pressure differential across the injector increasing at low MAP values which increases the fuel delivery (when you don't need it). You can correct for this in the VE table and it will work; but, your Ve table will not look like anybody else's Ve table and you definitely cannot use one of those automated Ve table generators to create a starting Ve map. Those automated generators are all premised on the basis of constant flow through the injector.

You definitely do not need a swirl pot. I suggest ditch the mechanical pump and mount an in line pump close to the tank. If you use the pump from the Nissan 280 Z (not cheap; but reliable and relatively quiet) it will work just fine as long as the pump is at the bottom level of the fuel tank - facilitates start up when the system is dry. There are other external in line fuel pumps available; but, I can only vouch for the 280 Z pump in terms of reliability. Run a 5/16 supply line from the pump to the fuel rail and a 5/16 return line from the regulator back to the tank. You can find on-line .pdf versions of the 1971 (and later) Volvo 140 and 1800 service manuals. Get one and have a look at the arrangement of the fuel pump, filter, fuel rail, fuel lines and FPR and get your design as close as possible to what Volvo used in 1971 and later. It will work just fine - did I mention that you don't need a swirl pot?

The best way to get the correct crimp tool is to go to your terminal vendor and purchase their recommended crimper. For the open barrel style crimps you are using I recommend a two step crimp tool. You have to crimp the conductor and then you crimp the jacket as a second step in a different die. I have the common as dirt ratcheting crimper with removable dies which attempts to crimp the jacket and conductor in one step. The dies are stepped to accommodate the difference in the jacket and conductor crimps. This requires that you exactly place the terminal in the die relative to the step, close the tool to hold the terminal and then insert the wire to the correct depth relative to the step and then crimp. Works sort of OK on big terminals. Sucks on small terminals because you can't see the positioning of the terminal in the die. With the two step crimp tool the terminal is not buried in the die and its easy to get accurate positioning. Cycleterminal.com has a nice selection of crimpers and if you know the brand and style of terminal you are using they can probably give you the hot ticket for the best tool.

Thanks for the information.
Sounds as though I am on the right track.
I kinda knew that the injectors would work, thanks for the confirmation. Yes, I will be using resistors in the circuit.
I have a 260Z pressure regulator from a previous dalliance with injecting a B20 and will be using that. I was hoping to go a little more "stealth mode" with the Duett.
To make sure I understand, the Nissan pump has enough suction to operate without a pre-pump?

TR Conn

TR Conn said:

To make sure I understand, the Nissan pump has enough suction to operate without a pre-pump?

TR Conn

Click to expand...

It probably does, if attached to a tank with good baffling around the pickup, which yours probably does not have. I would recommend that you run some form of a surge tank. There are inexpensive units on ebay that will house a bosh 044 internally that are about 6-8" cubed.

CW
Thanks.
I just ordered one!
I did a mock up and it looks like I can mount it under
the heater and feed it with the mechanical pump.
TR

TR Conn said:

Thanks for the information.
To make sure I understand, the Nissan pump has enough suction to operate without a pre-pump?

TR Conn

Click to expand...

Yes. Everything should be fine providing the suction tube extends to the bottom of the tank which it normally would. The stock tank for the 142E does have a baffle; but, as I recall when I did my tank restoration the baffle does not surround the fuel suction line. The baffle was to the side around the return line. Perhaps its function was to reduce splashing at low fuel level from fuel pouring into the tank from the return line. That is a problem you are going to have to deal with regardless of how you set up the supply side. It would probably be a good idea to set up your return line so that it is submerged under normal conditions.

You don't need tank baffles, surge tanks, accumulators or swirl pots unless you plan on pulling high extended Gs on a race track, dealing with much more acceleration than the pedestrian B20 can generate or plan on running hill climbs / Pikes Peak.

The original D jet pump and the Nissan 280 Z pump are rolling element positive displacement pumps. That is one of the reasons the Nissan pump is kind of pricey - more precision pieces. Positive displacement pumps are quite tolerant of negative suction heads. Turbine and centrifugal pumps which seem to be the more common design are not so tolerant of negative suction, that is why they commonly run submerged as in most modern cars.

If you want to dodge the cost of a positive displacement pump and the hassle of trying to retrofit a proper return line, I suggest you consider one of those in-tank retrofit kits. Aeromotive, In-tank and others vendors have them. Some of them come with a small baffle around the suction side of the pump and some of them include a proper submerged return line. This would give you a set up similar to later port injected cars running a single submerged in-tank pump with no surge tanks or swirl pot. Turbine style pumps are perfect for in tank mounting because they always have a positive suction head - until you run out of gas.

If you feel the need to install a surge tank supplied by your mechanical pump with the electric pump sucking out of the surge tank, be super careful with the sizing of your electric pump. If you run the return line back to the main fuel tank, your wimpy mechanical fuel pump will never be able too keep up with a big electrical pump and your electric pump will probably suck the surge tank dry. If you run the return line into the surge tank a big electric pump will re-circulate lots and lots of fuel back into the surge tank creating a potential nifty fuel froth. If you manage to deal with the pump and return line issues, give consideration as to how you are going to control the fuel level in the surge tank. At idle, the mechanical pump can pump more fuel into the surge tank than the engine is using. Under normal circumstances, the floats on a carb engine provide that fuel shut off function. You will need to ensure that you have some kind of fuel shut off / level control for the surge tank. If you overfill the surge tank you can pressurize it (if its fuel tight) up to the pressure limit of the mechanical pump (3- 6 psi?). This creates a back pressure on the regulator return line which can screw up your fuel rail pressure.

The surge tank / swirl tank is just an overly complicated bad idea. If you don't want to use an externally mounted positive displacement fuel pump located back by the tank, go to the in-tank submerged fuel pump solution with all the bits and pieces integrated together. Do what most automotive manufacturers have been doing since 1990.

142guy, you would NEVER run the return from the rail directly back to the tank with a surge tank setup. The surge is constantly fed by the mech pump or other low pressure pump, the high pressure pump sends fuel to the rail, unused fuel from the rail goes back to the surge tank, and a no pressure, free flow return line goes from the surge tank to the main tank that removes any air/froth from the surge tank and allows the tank to bleed off under conditions where the low pressure pump supplies more than enough fuel to fill the surge tank.

Most automotive manufactures utilize 2 things in order to not starve a high pressure pump, a highly baffled fuel tank, and/or a surge tank located in the fuel tank.
HONDA
MAZDA
FORD
NISSAN

Edit: I’m currently running a carb high flow pump for a v8 application that free flows nearly 2x what my high pressure pump flows. I have a 2liter surge tank. Prior to installation, I could not drive the car with less than 1/4 tank in town. Any corners and my afr would run dangerously lean and the car would buck.

If the OP is aware that he has to run the return line from the FPR to the surge tank and a separate large overflow line from the surge tank to the gas tank, that works. From the OPs general questions, I don't think we can make that assumption.

My essential point was that OEMs do not use external surge / swirl tanks. Since the OP presumably has not resolved the question of the high pressure pump yet it just strikes me that if he does not want to use an externally mounted in line pump located by the tank, the retrofit style in-tank pump with integrated baffles / reservoir (if you think you need them) provides a much simpler solution than messing with two pumps and a separate surge tank.

For high HP and extreme driving conditions all of this makes a lot of sense. In my case this set up is in what is basically a truck that is driven maybe 2000 miles a year and seldom sees anything over 4000 rpm.
I'm not too concerned with pressurizing the surge tank with the mechanical pump which is about 2 - 3 psi.
Modifying the fuel tank is not an option since as I noted in the original posting, I want to be able to return the car to stock and fuel tanks are NLA for this model. The tank is also a weird shape and I've found no fuel cell that would even come close to fitting.
It seems to me that the 1L swirl tank with the pump sticking out of the top and with the FPR return fed to the surge tank and the tank overflow going back to the fuel tank will fill my needs with a minimum of fuss and not too many holes to drill.


I appreciate the help and will be asking lots more questions as this project develops.
I am taking photos and will try to put a retrospective build thread together - mostly depending on results.
TR Conn

Run the return to the filler neck tube. Doesn’t have to be big. I’m running 3/8 (-6) hose to and from my tank, but the fittings on the original fuel tank are 1/8npt, so really 5/16 at the origin. It flows just fine and I have no cavitation or starvation issues. Also, no issues with heating the fuel or frothing fuel. That is why I’m running a surge tank, it severely limits the ability for pump starvation, and if set up correctly, no chance of foam, unless you put it there.

I looked at the filler neck. The only access is at a rubber coupling.
I drilled a hole in the fuel sender cap and installed a 90 degree 3/8 NPT fitting with a 5/16 hose barb.
TR Conn

That’s what I did.

TR Conn said:

I'm not too concerned with pressurizing the surge tank with the mechanical pump which is about 2 - 3 psi.

Click to expand...

This just reminded me of what I saw when I looked inside a mechanical pump. Between the arm that rides on the cam and the diaphragm there is a spring. When the diaphragm runs up against a wall of fuel (such as when the float bowls get full and the float valves close), it just stops moving. There is no danger of over-pressurizing anything.