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Hi to keep it simple I am building my daily driver (66 F100) I bought a fully rebuilt 240 inline six to replace the old worn out one in my truck. I want to get some better preformace out of my new engine. I want to get an intake, 2barrel carb, headers and a cam. What are some recommendations for me I have been looking at Clifford Performance parts but I have heard some negative reviews about them. I was planning on buying the Clifford 300 inline six kit that does fit the 240 also. This kit includes a intake, carb and headers the intake is the Clifford one , the carb is a weber 38 dgas (which I have heard good things and bad things about). I was planning on buying the Clifford 264 cam but I heard that they are bad and they don’t always come polished and will eat up your motor. The offy intakes and other products are also options what can you experts recommend I want somthing with a little more guts and I am a fan of the straight 6s. I am not looking to build a race truck. I want somthing decent on gas but I know it’s not a Prius.
Offenhauser offers a nice kit. The problem with changing to headers and a new intake is these setups often don't take into account the warming of the intake manifold chamber and so in colder climates you can end up having to deal with icing problems and longer warm up periods.
Look at your current intake and exhaust manifold and note how they are connected just below the carburetor. This induces a constant warming of the intake chamber to prevent icing. I noticed you were in New England so this might be a concern to consider.
Some of the intake manifolds allow for radiator fluid to be circulated under the intake chamber which provides the heat needed to prevent icing. Many do not.
You can always rig up something, though, if you find it is needed.
Im doing the exact same thought process for mine right now. a 300cid 6 in a '66 F-250.
Ive spoken to many at the various shows and events I attend and by far the owners of the Clifford system outnumber the owners of any others. Jegs has a 'kit' for adding headers, Offy intake and a 390 cfm holley, very similar to the Clifford set up, but everyone I've talked to seems to prefer the Clifford setup. Many also recommend the 2x2bbl setup, although I would no doubt go with the single for mine.
As far as a heat stove not being there, being here in San Diego, that's fortunately not an issue for me (worst winter I can recall was a low of about 40*F).
Your truck originally came with the C4 (11 trans pan bolt holes).
There is no such thing as a Cruise-O-Matic (C-O-M) with Overdrive, no such thing as a C-O-M metric transmission.
Yes I know I made a typo I have a AOD transmission my truck originally came with a 3 on the collum my truck has that transmission linkage to the carb for pressure regulation. I have an AOD tranny the pan says metric
I ran a stock 240 w/3 speed in a 65' long bed for a few years. It would do 100 mph if you wanted it to....everything was shakin though!! If I was wanting more power from a small six banger truck, I would bolt in a stock 300 and be done with it. Love your truck.
You might want to read a bit more and talk to a few others. These guys that build the 300 are certainly convinced that the 240 combustion chamber is smaller than the 300 carbed engine.
Read this one thread for example. Post #7 and #8. There are dozens of threads like this.
I rebuilt a 300 for my 66 to replace the 240 I put a mild rv cam from a local grinder, split manifolds from a later efi engine, and an offy intake manifold with a demon 575 carb. I have the dual port manifold but if I were to do it again I would buy the c series they flow better than the dual port. I wish I could tell you how it runs but I'm still doing metal work on the cab and have never ran it. If you already have a new cam in it I would just advance it a bit and put the higher ratio chevy rockers in people seem to have good luck with that combo.
Metric 
Trans it is not original obviously.
HELP daily driver 240 inline 6 performance
