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Hey guys, I have 64 f100 swb that has a 352 4v and Cruise-o-Matic in it right now. I am putting together a 390 for it starting with a nice shortblock I am getting with 2v pistons.
I use the truck to just cruise around but it still needs to be able to haul a load of mulch when I need to. I want to be able to run on pump gas (93 is fine). The truck has a 3.70 rear. I have a freshly rebuilt 4100 carb that I want to still use. I have the log manifolds with dual exhaust now but I will be getting headers for it.
I want to do this kind of cheap but I will splurge when it's worth it. The 352 has C6AE-R heads and C6AE-C intake. How will those do on the 390? Is there something better that I should be looking for? What size valves?
What cam should I use? I would like a bit of a lopey idle and it would be nice if I didn't have to change the torque convertor. (There don't seem to be many convertor choices for the COM anyway.)
my 390 has a set ported c6 heads. i would use the small valves that they should already have (2.02 or 2.03 int. and 1.55 exh. i think). im also using the crane 941 cam. it pulls pretty hard. how much compression are you going to have? that will determine how lopey of a cam you can use. you said youve got headers so that will help tremendously. also get a good ignition. there is alot of information on this topic if you do a search, or im sure someone else will chime in as well. my.02-good luck.
Yeah, the key here is the pistons and resultant comp. ratio. tell us more about the pistons you plan to use. Or, you might consider choosing your pistons to get the comp. ratio you desire. Something around 9.5:1 works well with pump gas, but allows you to pick from some slightly hotter cams (like the 941 listed above).
As I learned in this forum, using 360 pistons with the 390 crank and rods will raise the compression nicely. I'm no expert and my build is not complete yet. I asked these same questions a few months ago and ended up with thread chock full of information you should be able to find by searching. My build has ended up as follows:
390 with 360 pistons
.018" steel shim head gaskets
D2TE-AA heads ported and polished
Comp Cams 33-238 cam (not what most people recommend but I had already purchased)
Duration at .050: 218
Intake Valve Lift: 0.513
Exhaust Valve Lift: 0.519
Lobe Separation: 110°
Adjustable rocker valvetrain from DSC (1.76 ratio instead of 1.73 and has solid spacers in place of side load springs)
Edelbrock Performer RPM intake maniford
Headers
haven't got carb yet but most likely I'll stay with 600 cfm
The block has a date code of 7e7 on it. It is a low milage engine and it looks like it needs only a hone and rering done. The pistons in the short block now are the ford factory 2v ones. It would be nice if I could just re use those. I have gotten conflicting information on the compression ratio-- one person told me they were 8:1 and two told me 9.5:1. I would change pistons if it would help me out, but I still want to be able to run on pump gas.
standard truck 390 are low compression....If it has been rebuilt, then you need to know. They could be truck 390 pistons, or car 390 pistons...big difference
the engine came out of a torino but it wasn't original. The engine has never been rebuilt. I'll ask the guy if he knows if it is a truck block or not.
Pistons are cheap enough that I don't mind replacing them, and chances are that I might have to anyway if the block needs to be bored. So what compression ratio pistons would you recommend so that I can still run on pump gas?
Last edited by taylor0987; May 28, 2005 at 04:26 PM.
sounds like u got a few things to sort out still, but ill give you my recomendations... use the factory crank, rods, and pistons... if possible, see if you could get your hands on a cam with an rv grind, theyre good on power between idle and about 6000 rpm that ive noticed, which is good especially for pulling hills... id have a set of truck 390 heads re-decked down about .05", if a machine shop around you will or can do it... with factory head gaskets and your 2v pistons, that should bring your compression to about 9.4:1... id also go with an edelbrock performer 390 intake which is a dual plane design that will work good with the rv cam, and wont mismatch the intake-to-head ports enough to notice at all... i personally like the factory points ignition, because when set right, works flawless... with headers, look for about 340 hp and about 375 lb-ft of torque...