scrap 300 for one reason !!!
1 - The EFI manifolds are a split design- one for the front 3 and one for the rear 3 cylinders. Ford used dual downpipes that fed into a single catalytic converter at the factory to give a single exhaust pipe. The aftermarket pipes in the USA are "Y" pipes which give a single exhaust outlet and require an aftermarket catalytic converter if you are required to have one (not your '66!). Some people use the split manifolds to install a "true dual" exhaust on their truck. It's not neccesarily better than a single exhaust with a "y" pipe; having "dual exhausts" on pickup trucks may be an American affectation. But it may be simpler to build, due to less welding. The recommended exhaust pipe diameters are 2.25" for a single exhaust, and 2" or even 1 7/8" for dual exhausts. Any larger and the exhaust flow velocity drops too much and you loose torque.
2 - The EFI exhaust manifolds will work fine with your existing carbureted intake. The bolt patterns are the same, although the EFI exhaust manifolds do not bolt to your intake manifold like your existing design does. The carbureted trucks have the two manifolds bolted together to provide a "hot spot" under the carburetor to help fuel atomization. EFI engines don't need this as the fuel is atomized by the injectors at the valve port. I don't think you'll need this hot spot in the desert heat of Saudi Arabia. I don't have this hot-spot on my truck, and in Washington, DC, it runs fine in warm weather.
3 - Yes, the EFI intake manifold is a split design, with lower runners and an upper plenum. Ford used long runners on the EFI engines, which are good for torque. But the runners ended up being too long to reasonably be a single-piece manifold (either due to manufacturing or installation at the factory), so they split it into upper and lower portions. The EFI intake manifolds cannot be used with a carburetor. I would not recommend trying to convert your '66 to EFI either. Too much trouble. There are good aftermarket carburetor intake manifolds for this motor, made by both Clifford and Offenhauser. which will allow you to run a 2bbl or 4bbl carburetor. The stock carburetor is adequate, but there's more performance potential in the 300 motor than the stock 195CFM (1/2bbl rating) carb is going to give. With the addition of a mild camshaft, the intake/exhaust/cam combination will produce at least 50% more power. But this may not be a concern to you. If all you want is your exhaust leak fixed, then just the EFI exhaust manifolds are fine.
4 - The regular gaskets are fine. The port, bolt and mounting patterns never changed on these motors, from their inception around 1966 through the end of production use in 1996 and end of production entirely (agricultural) in 2001/2002.
If you look in my gallery, there are photos where you can see my newly-installed EFI exhaust manifolds underneath the aftermarket intake manifold and carburetor. I did almost exactly what you're trying to do, but I used a new intake and carburetor.
EXHAUST MANIFOLD ALWYAS LEAKING,
sometimes it leaks at the Cyl head, other at the mating surface with the intake manifold.
I changed gaskets 6 times a year maybe more.
Anyone got a trick to eliminate this leak, saves me extra cost of swpping into V8-352.
I appreciate all your ideas.
66 Ford F100
I-6, 300
1984 Carter 1brl carb with elect choke
380KM with full tank (69 Lites)
Hamid.
What does gas cost over there (per liter price is fine). Your fuel economy is awful for that truck, unless you're pulling a load or driving really fast (120km/h), or have a really tall rear axle ratio. Do you pull a load? What kind of driving do you do? Generally, for 69 liters of fuel, I'd expect you to get 450+km routinely.
I never thought to look at the weather in Saudi Arabia. It actually gets near freezing sometimes. You'll definately need some manifold heat then. The easiest way to do this, is when you disassemble your intake/exhaust manifold, there are 3 bolts holding the two manifolds together, and the intake manifold has a recessed area at the mating surface. The Ford factory design circulates hot exhaust across this recessed area at low engine temperatures to keep the manifold warm. The common alternative to this is to use water jacket heating. Fabricate a plate to cover this recessed area, with fittings on the plate for 5/8" heater hose. Connect this in series with your heater hose. Make sure you wash the recessed area of the manifold well- it will now be part of your cooling system. Now, when you run the engine, the manifold will have a constant, stable 190+ F heat source. The old Ford design would get stuck or rust out and give completely unregulated manifold heat.
This is a great article that talks about someone fabricating a plate and water-heating their intake manifold (they also used it to mount their starter solenoid): http://cars.rasoenterprises.com/Prod...20heater%20kit
wow, lots of info pal, I will answer you by the article numbers:
1-So I don't need that upr & lwr intakes of the EFI, good, and the single or daul exhaust pipes are no problem to me I can do either one.
2- another good thing I still can keep the old carb on the old intake, but lestin to this ( my old thermactor exhaust valve got stuck and I weld cut it and removed it from the exhaust manifold) truck performance still the same nothing major occured. It is pretty hot where I live and as you said that type heating is not rally matter.
3- I agree with you the after market manifolds (Clifford/offehauser) plus 2brl or 4brl carbs will boost power but for me and according to no much competition I dont need that extent of power gain.
4- I can use the old gasket, wounderful, Thanks dude, and as the saying( I will do somthing good for you someday).
I will answer to your last post about gas consumbtion on my next reply.
Last edited by ftrk66; Dec 17, 2007 at 10:32 AM.
tighten all the bolts into head first then tighten the two manifolds together I did it
the wrong way 3 or 4 times before my uncle told me this trick never leaked again.
you can get the permatex and probobly a s$$t load of beef jerky and kool aid in a kare pac from a freind or family member
cant belive you found a 300 in sa
Here I am answering your next post starting with gas prices:
Now in Saudia Arabia we have 2 types of Gas:
A)- 91 Octane = .119 USD a liter = .538 USD a gallon.
b)- 95 Octane = .159 USD a liter = .718 USD a gallon.
I know that engine is a sucker, it was a nightmare with the original Ford 1 brl carb, a whole tanks lasts me only 200km, but when I put the 84 year model Carter 1 brl elect choke it improved to 280-300 km per tank, I believe it can last me up to 350km, I will do some calculation later and let you know, (disregard the figuires i my 1st post).
Despite the fact of fuel consumption, I never cared due to the low gas prices around here. I don't do pulling, and I drive average of 110-120 km/h (70-75 mph).
It gets to the freezing point somtimes in the northern part of Saudia Arabia, It is pretty warm here in Jeddah City at the mid west coast.
Talking about the water jacket mod, I got the idea, but let us talk about that when I buy the manifolds and start to install it on my 300 engine.
Now my next thread will be ( I WILL KEEP THE 300 FOR MANY REASONS)
That was nice talking to you about my exhaust problem, I appreciate all the info you dropped in this thread, I honored to be a friend of yours, maybe some time wil get together in the US as I am planning for atrip later. I used to go to schools, in Melbourne, FL, Winston Salem, NC, and San Antonio, TX back in the period of 1979-1983.
Solong. Hamid
Last edited by ftrk66; Dec 18, 2007 at 06:26 AM.
Ford Trucks for Ford Truck Enthusiasts
Hi dude, thanks for the trick, I will keep it in mind when I install the EFI exhaust manifolds, but do me a favor and explain this part of your post.
(you can get the permatex and probobly a s$$t load of beef jerky and kool aid in a kare pac from a freind or family member
cant belive you found a 300 in sa)
I'm glad to help out. I'm honored to have conversed with someone as intelligent and good natured as yourself. Good luck with your truck, and good luck with life in general! May you be prosperous and protected from governments, both domestic and foreign.
Here I come agin on my exhaust issue:
I bought the front and rear 87, 4.9L exhaust manifolds, fit them on my 4.9L engine, done some cutting and filing, align them and they are rady to install.
Now I gt to find or modify the inlet pipes (y) shape.
my question is: Can I buy this inlet pipe at a local store, I need a part number that I can order, else what is the website I can ordr from.
I appreciate every advise in this topic?. Thanks.
Hamid.
There is absolutely an aftermarket pipe available. It'll be either Walker or Dynomax brand, it's part number 45166, and at least here in the USA, is carried by many retail parts stores, including Advance Auto, Schucks, Kragen and NAPA. I bought mine for $65 from Advance Auto.
This pipe is a "Y" pipe, which connects both manifolds to a common pipe, and follows the factory routing. It will just bolt right in. I had to wiggle mine around some to clear the crossmember, but my engine mounts may have been sagging with age. You'll need hardware to connect the y pipe to the manifolds, either 3/8" or 5/16" diameter, and I forget how long. Probably 2 or 2.5 bolts will be required, as well as nuts and lockwashers if the flange threads on your manifolds are damaged. Mine were, and I had to use nuts.
The pipe has an O2 sensor bung built into it; mine came with a plug for it.
If you have a decent exhaust shop near you, who can bend pipe, cut and weld, you might consider having something fabricated. Many people on this forum have done so, with significant cost savings.
I had to do a little filing and cutting to fit on the head, easy installed and aligned, took the truck to a pipe shop for daul inlet tube fabrication, cost nearly 90 bucks, after all the engine sounds like new I swear, very smooth and quite. I hope this will last long.
Many thanks specially to Boblue88 and all other members.
Yours:
Hamid.


