Just picked up a 68 s-code 4v intake off a 390 for my 360. Other than a new spacer plate and my choice of carbs (prob an autolite 4100), what else will I need to make this change? It's a 71 F100 360 2bbl currently.

Also...did Ford only make truck FE engines with 2 barrel carbs? Seems like that's all I ever see on them and I don't get it....big trucks, big blocks with 2v's...what was their reasoning?

 

I have a Haynes manual covering 73-79 trucks and the only 4V carb mentioned in that manual for Fseries trucks is on the 460. My guess is that the object of the "big-block" motors on pickup trucks was low RPM torque for hauling loads rather than posterior. I think that the big 2v carbs could handle this lower rpm stuff. I've had both 2v and 4v carbs on 302's in Fseries and also both 2v and 4V carbs on 390's in Fseries. In both instances I had Edelbrocks Performer series manifolds and a 600 Cfm Edelbock carb. The 2V setups were stock Ford w/ Motorcraft carbs. I'm currently useing a 390 w/ 2V. My expirience is that the 4V setup isn't obviously better than a good working 2V. I haven't had a fresh engine yet that has anything more than adequate compression, and nothing especially special about the cams that have been in my trucks. I like my Edelbrock Carb for it's good operational manners, but until I have my other 390 rebuilt, I'm not going to bother changing my intake manifold to use it when the stocker is not leaking and running fine. I've heard some say that the regular Edelbrock performer manifold on an FE isn't that much of a performance booster aside from weight savings, that the Performer RPM is a better choice. If you have a fresh engine, I'd consider opening up the exhaust restrictions (headers) and getting a good cam recommedation to match your gearing, intake, and carb.

BBT

 

I read somewhere on another brand of car, that the factory only put a 2bbl carb on large heavy vehicles because they where afraid the rpm would not be high enough in some situations to open the rear barrels on a 4bbl carb, thus the reasoning of putting a large 2bbl on. Maybe Ford was thinking along these lines too.

 

Good Post BBT, Everyone wants big carbs, cams, and headers on their trucks, myself included in that crowd. But I have reformed, My engine is foot limited to 4000 rpms. There just isn't any rerason to put all that stuff of an engine that isn't turning over 5000 rpms.
Got the long tube headers too, took about 8 hours to remove em, replace a starter and button it back up, only to face doing it all over since the starter didn't survive 25 cranks.

I do feel that dual exhaust is one of the best bangs for the buck. :-)
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The 390 finally got a 4V intake in ’75 but only for the 2WD’s. Casting number D5TE9425MB.
Attachments:

 

No M code 4WDs? Interesting. I understand that "T" intake pictured was not available for vehicles sold in California.

 

Start with your exhaust. Fords are restricted on the exhaust side and this has always been where I get my big gains. My 351M has full length headers and it pulls very strong. You will not see a HP gain until you can clear the chamber and exhaust is how you do it.
Most 4V applications had 4V heads that went with them, didn't they? these H.P. applications can only be rated at the top end, that is, at high RPM. You'll never know you've got a 4V until you rev it up over 4500 RPM and then you'd better have the valve train to keep up. The previous post stated he would wait for a fresh engine. He has probably wasted some money in the past to learn this experience. Take it from someone whose wasted plenty. Save your fancy parts until you can package what you want. All parts must match. cam, heads, intake, carb, exhaust and valve train. Other than that its easy.
KingFisher

 

Good points....should have mentioned that the engine is rebuilt and sitting on a stand right now...picked up a stock ford 390 4v intake locally...planning on using the stock exhaust manifolds with 2.5" pipe, dual exhaust and lower than stock restriction mufflers.
In light of some of your comments, got me thinking about carbs...
If the 2v carbs on a truck are a higher cfm than the primaries on say your regular autolite 4100, and the secondaries won't be opening much due to lower rpm it would seem that this mod would actually lower performance...unless you used a 4v carb with larger primaries....
any thoughts?

By the way, if you buy...say..a holley 650...is that 650 cfm measured with all 4 barrels wide open....and does anyone show a breakdown of cfm per pair of barrels?

 

650cfm or whatever cfm would be total all barrels open. I would say putting the wrong carb on, or going to a 4bl from a 2bl maybe would affect driveability during towing or some other extreme operation at low rpm. But as someone else said, if you design it as a package, you could gain lots of hp. If you raised the rpm the motor made hp, along with changing the final drive ratio to a higher number, you could benefit in some areas such as power, but lose gas mileage.

 

Had another thought....since I'm building basically a daily driver could the 4 barrel actually improve gas mileage....I want the 4 barrel for when I want to floor it on the freeway....so if the 2 barrels I would be using the majority of the time are smaller cfm than the 2v...wouldn't I move less fuel during normal driving conditions....as long as I stayed off the pedal (most of the time...i'm not as agressive a driver as I used to be)......
Planning on no other mods to the engine...just the dual exhaust and 4v intake.

 

your right, the smaller primaries of a 4 bbl with yield higher gas mileage, and better low end throttle responce that the big 2bbl venturies, keep in mind, you gotta stay outta the 4bbl's

 

CPE,
You will see performance increases. You may be encouraged to push your truck or drive it harder because it has a more powerful engine when in fact your just burning more gas. Going to a four barrel and dual exhaust are the two cheapest investments vs. HP return for the buck.
Good Luck, Have Fun,
KingFisher