2 barrel on a one barrel adapter

Mikejax25

New member
I'm trying to make my 86 f150 as fuel efficient as I can. I want to put a sniper efi 2300 on my 300. I was wondering if any one had seen any fuel economy improvement. I'm not looking for performance gains just fuel economy. Is the 2 barrel to 1 barrel adapter a good way to go or should I buy once and cry once and spend the extra 380$ on an offy intake and reduce it down to the 2bbl sniper efi?
 
You don't want a one barrel adapter because it will create a pressure drop between the base of the throttle body and the intake manifold and since the MAP sensor is in the throttle body it will not be able to read the intake manifold absolute pressure.

You can use the stock intake if you machine the carburetor opening wide enough for both barrels and make a two barrel adapter or just get the Offy "C" intake.

Are you going to let the Sniper control the ignition timing?
 
Since the Sniper requires high fuel pressure, what are you going to do for a fuel pump system?
 
I'm looking into a few options. My truck has a 16 gallon tank so I've been thinking about an intank fuel pump in a bigger fuel cell. I also thought about an inline pump. I work In one of the major chain part stores here in the us so i find all kinds of pumps i could use but if i go the route with the inline pump I may just order the efi kit that comes with the pump
 
If you get an EFI kit then just use the entire Ford 4.9 intake manifold with injectors.
Should be able to find one fairly cheap at a Pull and Save yard.
 
Mikejax25":1nxfjl1z said:
It's my understanding an efi manifold wont fit the carburated cylinder head

The EFI lower intake is used often as a basis for custom carbureted intakes on the carbureted head.
There are 3 extra holes in the EFI head for additonal support for the two peice EFI exhaust manifolds but again the EFI exhaust manifolds are use on the Carbureted heads very often leaving the extra 3 hole in the manifold unused.

It is recommended to switch to the EFI exhaust manifolds especially if using the EFI intake because the intake doesn't need the exhaust heat riser on the exhaust log manifold and the EFI exhaust does a much better job than the log exhaust manifold.

The 1986 300 is a low compression engine.
If you want to pick up fuel mileage, if you swap to the EFI head you increase the compression by .5 and you also get the EFI swirl, fast burn chambers for addition fuel efficiency.
 
I guess I should mention that my engine is a rebuilt engine with some goodies in it. Mainly flat top lightning bolt pistons...... that being said I have 122 psi on the weakest cylinder. I plan on doing the holley because it has more tuneable options for the map. I also like that they have a module for my hei setup.
 
I have a Sniper 2300 on my 300 and I would not use the stock log manifold.
I have an Offenhauser C on mine, and it fits really nicely.

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It seems like putting it on the stock 1bbl intake would really throw of its ability to properly meter the fuel. It uses manifold pressure for everything, and necking it down seems like it'd cause problems.

I also suggest using the EFI manifolds and getting rid of the stock log exhaust manifold. You won't need the heat riser with the Sniper, so you might as well let the engine breath better.

Lastly, I don't think there are any options for timing control on the 300. I asked Holley and they said there are no aftermarket units available, and recommended against trying to set up either the DSII or HEI unit for timing control.
I'd love to be told I'm wrong on that though, since I'd love to set it up.
 
I swapped the efi exhaust when I did the head gasket last year. I gained maybe 500 usable rpms and and maybe a half second to 60mph. Not bad for a nearly free swap. I had a machine shop drill and retap the flange ends cuz I had to torch the studs off, 2 m18 o2 sensor plugs, and a pipe plug for the egr hookup. Worth every penny
 
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