Alright, as the title says, I'm wondering about the pros and cons of each engine. My f150 has an injected 300 in it currently, and hopefully it stays in there for a LONG time. BUT... I found on craigslist a 4.9 with 106k on it with everything, for less than 350 bucks, and am tempted to get it just incase anything ever happened to my engine. Even a new head costs $300, so I could use it for parts if I ever needed to. Also, while browsing the ads, I saw a brand new long block for carb models up to 84' I believe. It is brand new in wrap, for $700. If something ever happened to my engine would it be better to just swap in the other 4.9 with no messing around, or put in a carb'd model? I have heard the tall tales of old 300's with carbs getting over 20 mpg in f250s, and wondering if there is any truth to it? Or does the EFI do better than any carb'd model? Thanks for your imput.

Also, I found a t18 that I could prob pick up from a friend for less than $100. I have the M5OD in my truck, and I get up to 18 mpg, usually around 16ish though. Would losing overdrive affect my mileage much? I run right around 2000 rpms at 65mph

 

FYI: I have the 3.08 gears and 30" tires

 

Unlike the small V8s the 300I6 and 460V8 have unique EFI heads so that carbed longblock is no good to you for parts unless you switch the truck to a carb, and yes losing overdrive will have a big impact on highway fuel milage.

 

With the same gear ratios my 92 4.9 gets 18 With a m5od. My 90 4.9 with a t18 is 13mpg, same speed and driving trips. Nearly identical trucks with both engines in similar condition (very good). In my case having OD is significant with gas prices as high as they are.

 

Kind of related, but I assume from what Conanski posted that there are no carb'd manifolds made to fit EFI heads? That will hose my plans for the '64 if so. I have an EFI 4.9 that I planned to make carbureted. If not I guess I'll be sticking with EFI, at least I still have the donor truck.

 

wow.. def food for thought. I think I'll stick with the 5spd. In your opinion, you reckon it is worth the hassle for doing a ZF tranny swap? I want to drive this truck for a long time, but don't plan on doing any serious hauling.