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351W mods

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
Alright folks... This summer I plan on making the 351 get a little worse gas mileage. :cooldude:

I plan on getting shorty headers, but was wondering what kind of things that should be the first step in letting this engine do better than it is stock. Bolt-on mods are good, because I don't have the convenience of being able to park the truck and work on it for a few weeks.

Ryan
 

6L PWR

Kansas Chapter member
Not to mention they're easier to paint prior to installation. :rofl:
 

Fellro

Moderator
Staff member
Ditch the factory exhaust for sure... I don't have a lot of tricks for them, but will be watching as well, as the nephew has a Mustang I will be putting together for him, likely will go Winsor, since it is too much BS to put anything bigger in a 66.. I don't feel like hacking shock towers and relocating them.
 

blacksnapon

Moderator
Staff member
NAPA has long shanked carbide burrs that do wonders with intake and head passages (cleaning them up, and gasket matching). The ones that I've done, that unlocked more horsepower than any modification.
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
alright vince, you have my attention.

Tell me more. I know what a carbide burr is, but I'm unsure exactly what I'd go about doing, and am not quite sure what you mean by 'gasket matching'

Ryan
 

blacksnapon

Moderator
Staff member
alright vince, you have my attention.

Tell me more. I know what a carbide burr is, but I'm unsure exactly what I'd go about doing, and am not quite sure what you mean by 'gasket matching'

Ryan
Inside the intake passages in both the intake manifold and cyl heads, is rough finished casting. Use the burrs and a die grinder to smooth out the passage (better air flow). Gasket matching is when you put the intake gasket up to both manifold and heads, mark the opening of the gasket on each, and use the die grinder to shape the opening to "match". The reasoning behind this, sometimes the airflow will actually hit a 1/4" ledge of casting. Again, "smoothing" out the airflow.YelloThumbUp
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
awesome... I'll find a few days during spring break where it's okay to park the truck for 1-2 days and do this. You have any arbitrary figures as to how much this may help?

Ryan
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
I have a lot of crap inside of my intake manifold. It's gummy and black. I'm not sure if it's oil or gas that's built up over the years, but I guaruntee I was the first person to lay eyes on the inside of it since 1993.

Ryan
 

6L PWR

Kansas Chapter member
I have a lot of crap inside of my intake manifold. It's gummy and black. I'm not sure if it's oil or gas that's built up over the years, but I guaruntee I was the first person to lay eyes on the inside of it since 1993.

Ryan
So, it looked like the inside of a diaper back when you were still wearing one. Kewel.:rofl:
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
Had another question, Vince... Is there anything I should do to the intake arm? I'm certain that thing would create tons of turbulence with the way it is built. Remember how it is molded? I assume that's to help flexibility? Either way, I should smooth out the inside of that stupid thing.

Would a K&N air filter be a good thing to throw in there at the same time to boost some miles per gallon and a little power? I'm not sure how restrictive those Motorcraft filters are. I don't drive on gravel too often and am usually out in clean air.

Ryan
 
You may want to consider taller gearing for better mileage. I don't know what ratio you're turning now, but if you really don't do much in the way of trailer towing, taller gears may be the way to go. Maybe even a Gearvendors Overdrive unit.
 

O'Rattlecan

Redneck Prognosticator
26,687
797
Belton, MO
meh, the only taller gearing I'll be doing is slightly larger than stock tires. It's a 3.55 in the rear end, and I really like it as the 'do everything' gear.

Ryan
 
No doubt about it, 3:55 is great. as I had said, I wasn't sure what you had in there. You may still want to check out that gearvendors over/underdrive... they have an awesome unit that could both increase your pulling power and increase your highway mileage by 20% (approx.)

Also put a tannau cover on that bed. It cuts down on the turbulence created behind the cab.
When was the last time the CAT was changed? there are a number of high-flow cats out there that will also increase mileage when used with a high flow muffler (flowmaster, etc). Replace the 02 sensors as well. As they age, they become less responsive to changes in driving conditions, therefore keeping the fuel mix LESS than peak. there are also kits out there that can "trick" the 02 into leaning out the mix, but if you use those, you have to be really careful not to "set it and forget it", since you WANT the proper mix under load and such.
You also might want to consider installing an electric fan. for about 200 bucks you can get a really nice one and eliminate the gas hog on the nose of the waterpump, possibly extending IT'S life as well... not to mention I have seen clutch fans come apart and do 800 dollars in damage.
I put bosch platinum plus fours in my van four years ago and ran 9mm silicone cables, upgraded the coil, etc... and ALL those parts are still slick as a whistle. I just did a cursory plug check and they look almost as good as when I got em.
 

6L PWR

Kansas Chapter member
I just did a cursory plug check and they look almost as good as when I got em.
Unlikehow you look to your wife! ROFL

Great advice Tom. Now that my wife's Taurus got back from the body shop I plan on replacing the plugs, wires and O2 sensors. It's got 90,000 on it now and they've never been touched. That should help her little car out as well.
 
Yessir! sounds like it's due for all those great changeovers. Don't forget the timing belt, the cat, the tranny flush and change the air in the tires while you're at it~!
 

6L PWR

Kansas Chapter member
Yessir! sounds like it's due for all those great changeovers. Don't forget the timing belt, the cat, the tranny flush and change the air in the tires while you're at it~!
I can understand the timing belt and tranny flush, but what about the cats? It has two for some stupid reason. Is there something I should really do for them?
 

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