I used the car for work now and again, the journey was about 150 miles each way, which let me see the fuel consumption, feel how the car drove in traffic and at speed and generally shake out some bugs.

Bug 1 was the spark plugs...

The top one is Edelbrock's recommendation, the bottom one is what was fitted. That helped to explain the lazy running and hard starting

 

I did some research (we're back in 2017 at this point) and the best bang for the buck appeared to be FAST EzEFI. This is a pretty simple throttle body EFI with a stand alone ECU and a simple fuel system. I didn't want timing control because I can time and engine and I believe that vacuum and centrifugal advance is plenty for a mild street small block.

This is where I had to

chose an intake, and recieved wisdom is that a sinlge plane is best, so a Ford Motorsport one was ordered up. This in let is a Victor Jr with Ford branding, but at the time was $60 less expensive. Yes, I'm on a spouse approved budget. (Don't tell her every purchase though)

 

The homemade heater outlet is the only way I could come up with to have the EFI temperature sender and the gauge sender in the same part of the water jacket. Not too pretty, but it works OK.

 

The EFI kit came with pretty much everything required, less a few sundry items. The harness and ECU looked scary until I attached all the sensor connections on the throttle body and mocked it up on the bench.

The ECU is about the size of a deck of cards and hid up well above the glove box.

This shot gives an idea that once the air filter is on, there isn't too much 21st century on show

 

The fuel system is pretty standard by my understanding. The requirement for the pump to be close to and below the tank and have a return line is common to most retrofit systems. I had to buy a new tank (the old one was pretty dented and creased) so I could weld on a 3/8" NPT bung in safety. My return line goes into the original outlet on the sender (minus sock) which is below thw fuel level and doesn't aerate the fuel.

The fuel pressure regulator is on the firewall, passenger side.

The kit came with the fuel fittings shown - I had to but a few more because I'm fussy and wanted as little as possible on show. The fuel line is push fit, but I added hose clamps as insurance.

 

The O2 sensor bung went into the passenger side header, pointing straight down so as to shed any condensation. My old split Tri Y headers bit the dust as part of the AOD upgrade...

Those cracks were caused by excess heat retention from the header wrap I reckon.

First time I've had the budget for coated headers!!

 

The rest of the install was pretty straightforward. Connection for power goes straight to the battery, good clean grounds are essential, avoid running EFI cables near to plug wires, all the usual good practices....

The first fire up and test drive went OK. Not awesome, just OK. I had to spend a week or so tweaking timing, advance curve, A/F targets but with time I got to a point where the whole package worked really well. No stumbles, no burps, instant fire-up hot and cold, good throttle response, steady idle.

That was the tail end of 2017, and now here's the reason for the thread title....

I couldn't help wondering if a great big single plane inlet was too much for a little 289. Wouldn't a dual plane help the torque at low revs? Could I make a good running enginerun even better? Did I choose the wrong manifold first time round?

The solution seemed to be to read up on the web. After disappearing down many engine article rabit holes I decided the only way to find out was to just buy a decent dual plane and find out.

Yesterday was the swap day, and the car is back together, but the weather hasn't let me do anything except start and idle it.

Stay tuned...and thanks for reading

 

Very interesting. I am about to take the plunge on EFI, and have the dual plane RPM air gap on my 351W, so this is very timely for me. What I have gleaned from reading endless threads on dual plane and EFI is, you need to run a spacer, (I don't have the hood clearance) or notch the manifold divider, like this pic.

 

And the air gap intake does have a portion of the divider cut out

 

My 351W air gap manifold does not. Maybe it's an early version.

 

Ah, my 289 does, as the one in post#8 above, I haven't seen one for a 351

 

I look forward to the results!

 

Well folks, the results are in and in my case they're a win for the single plane.

The Edelbrock Performer RPM Air Gap doesn't suit my application at all, even with a 1/2" open spacer. As I don't have enough room for a bigger spacer I'm admitting defeat.

The EFI couldn't cope with anything above 1800 rpm without spitting and sputtering, causing a hugely rich mixture and stalling on return to idle.

I gave it about 40 miles (which is about half what the single plane took to run acceptably on initial set-up), I played with the timing, I played with the AFR targets, I did as much as I could while losing heart.

I'm going to revert to the single plane and chalk up the cost to experience.

On the subject of hood clearance, a Victor Jr is within 1/8" the same as the Performer RPM Air Gap with a 1/2" spacer.

As ever with single point experiments, your results may vary. If anyone has watched the Engine Masters where they did carb vs EFI then they'll be familiar with the theory that retrofit TBI systems need a single plane to ensure good fuel distribution.

Ok gang, it's 1630 here and the sun is above the yardarm which means I'm off for a beer!

 

Nice build.

Here’s a thermostat housing that you could mount your temp sensor.

Thermostat Housing, Water Outlet - #8592-3B - National Parts Depot

Buy part #8592-3B Thermostat Housing, Water Outlet for your classic vehicle from National Parts Depot. Free shipping on orders over $300, fast delivery & everyday low pricing! Order now!

www.npdlink.com

 

Thank you! I did consider a stat mounted sender, but I wanted to have both senders on the engine side of the stat to watch how the warm-up fuel enrichment worked.

 

English, your story demonstrates very well the huge flaw in many aftermarket fuel injection systems. The OEMs had fuel injection on dual planes for years, and it works very well. GM sold millions of cars and trucks with Rochester TBI on an iron dual plane. Ford, in 83,84,85, and the first few months of 86, sold cars with a 302 on an aluminum dual plane with a 2 barrel throttle body called CFI. These cars also had an AOD and 2.75 axle gears, they performed their job well.

So, why can't the aftermarket guys do this ? Because they're idiots, thats why. If you look at the factory systems, they have carefully placed the port for the MAP sensor in a spot where it sees the manifold vacuum of both planes of the intake, and ports for PVC and power brakes and vacuum advance and whatever else are in a spot where they won't interfear. If you look at the MAP sensor on your EZ, I'm betting that it is off to one side where it doesn't get a good signal from both planes. Lots of the aftermarkets are setup this way. Where is your PCV port ? Is it cycling on and off and causing confusion for your computer ? Do the instructions tell you, like many papers written for emission era cars, to always use ported vacuum for dizzy advance ? This is also wrong, but is the default advice for many parts. Its there to avoid liability to the part manufacturer for 'tampering'.

Then there is the fuel curve, the aftermarket guys don't have Ford, Chrysler or GM helping them figure it out, so they struggle. The OEMs got this stuff figured out decades ago, and some of the aftermarket is still catching up. The most trouble free throttle body fuel injection out there now is Rochester, GM engineered it for them and it has been applied to almost everything.

If you want an extra 20~25 lbs-ft of torque at lower rpms, you can have it, but you'll need either a taller open spacer, or a deeply notched divider ( the ones pictured in this thread are not cut deep enough ), and to reprogram the fuel curve to give much more enrichment at tip - in under low vacuum. If it isn't already done this way, hook your dizzy up to full manifold vacuum. You CAN do this, just takes some extra thought. And you already have the dual plane !

LSG

 

English, your story demonstrates very well the huge flaw in many aftermarket fuel injection systems. The OEMs had fuel injection on dual planes for years, and it works very well. GM sold millions of cars and trucks with Rochester TBI on an iron dual plane. Ford, in 83,84,85, and the first few months of 86, sold cars with a 302 on an aluminum dual plane with a 2 barrel throttle body called CFI. These cars also had an AOD and 2.75 axle gears, they performed their job well.

So, why can't the aftermarket guys do this ? Because they're idiots, thats why. If you look at the factory systems, they have carefully placed the port for the MAP sensor in a spot where it sees the manifold vacuum of both planes of the intake, and ports for PVC and power brakes and vacuum advance and whatever else are in a spot where they won't interfear. If you look at the MAP sensor on your EZ, I'm betting that it is off to one side where it doesn't get a good signal from both planes. Lots of the aftermarkets are setup this way. Where is your PCV port ? Is it cycling on and off and causing confusion for your computer ? Do the instructions tell you, like many papers written for emission era cars, to always use ported vacuum for dizzy advance ? This is also wrong, but is the default advice for many parts. Its there to avoid liability to the part manufacturer for 'tampering'.

Then there is the fuel curve, the aftermarket guys don't have Ford, Chrysler or GM helping them figure it out, so they struggle. The OEMs got this stuff figured out decades ago, and some of the aftermarket is still catching up. The most trouble free throttle body fuel injection out there now is Rochester, GM engineered it for them and it has been applied to almost everything.

If you want an extra 20~25 lbs-ft of torque at lower rpms, you can have it, but you'll need either a taller open spacer, or a deeply notched divider ( the ones pictured in this thread are not cut deep enough ), and to reprogram the fuel curve to give much more enrichment at tip - in under low vacuum. If it isn't already done this way, hook your dizzy up to full manifold vacuum. You CAN do this, just takes some extra thought. And you already have the dual plane !

LSG

Unsurprisingly harsh on the aftermarket people. Life is a little easier for the car manufacturers as they have only one car they have to dial in, and with much greater resources.
The aftermarket is trying to accommodate an infinite number of variables: intakes, cams, ignitions, displacement, etc.
That they are able to provide an affordable, tunable system is worthy of a lot of praise. Sure it may take some efforts to get it dialed in but it’s no different from what tuners and their dynos have been doing for carbs for decades.

 

LSG - you are absolutely correct regarding the placement of the MAP sensor. Going forward, I will try cutting down the centre divider as a taller spacer isn't possible due to hood clearance.

I put the single plane back on this morning so as to be able to use the car until I go back to sea, but I'll regroup and buy more intake gaskets!!

 

Edelbrock Pro Flo-Flo 4 appears to have a single-plane manifold.

 

I've been looking at my Performer RPM dual plane in light of LSG's comments. I suspect that I could drill and tap a runner for each of the planes and tee them up with hard line. This would allow a remote MAP sensor to see balanced manifold vacuum.

The PCV port is part of the throttle body, which puts it in the shared plenum, so I think that is not a factor.

My centre divider is only milled down anout 1/4" - in combination with the 1/2" spacer this is not sufficient to equalise the fuel distribution. From my understanding of TBI, the firing of the injectors may not line up with the fuel demands of each bank. This means that the left bank might starve briefly while the right bank floods - hence the need for a large open plenum beneath the throttle body.

Does any of the above sound correct, or am I off on the wrong track?