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Discussion Starter · #1 ·
So my 352 took a dump on me. Bought a running 390 which turned out to be anything but, and it's got a 360 crank in it to boot. So there's a sad story there, but regardless I'm going to press ahead with a 390 rebuild.

The block appears to be std bore, date coded Dec 66, which is good. With a 2U crank and some C7AE-B rods (I think that's the stamp on them), I can have a bottom end screwed together. The heads are C6AE-A, and appear to be in serviceable shape. To top it off, there's a Performer intake. So the basics are there.

Now, onto cam choice. I've been looking at the COMP Cams Dual Energy Camshafts 33-207-3. Something that will give me a big more bump, but one that can still be used with a stock convertor. Naturally, matched lifters and so on.

Car is street driven daily, runs 3 to 1 gears behind a cruise-o, which will no doubt morph into a rebuilt C6 when more funds permit. Stock manifolds for now, Holley 600VS, which may be turfed for a slightly larger one down the track.

My questions...

1. Anyone running that cam here? How is it? Can you use stock valve springs?
2. I'm considering a pair of alloy heads in the not too distant future, so linked to point 1, I don't want to spend money on my C6AE heads so I'm thinking I might just throw them on as they are... new heads will come with appropriate valve springs, so why spend money twice?
3. In terms of the bottom end, I'll be ordering everything from Summit. I've used Clevite bearings before in a previous 351C build - are there any brands to avoid? Also, pistons... thinking about Keith Black Hypereutectics, with matched moly rings. Are these OK for a mild build?
4. Machining... have heard that its not a good idea to zero deck FEs; is that true? Well, anything more than making sure the deck is flat gets conflicting opinions on whether it should be done. Trying to keep factory compression ratio of about 10 to 1, although I will be running 98 octane exclusively, so I guess if it ends up being a little more, with that fuel is should be ok with another half point. I'll be running my existing MSD6A ignition so big sparks won't be a problem.

Can't think of anything else to ask for the moment. Still getting over the trauma of the 360 crank in there, not to mention the missing oil pump shaft which no one noticed, resulting in a bad sounds when I put the motor in and got it running. Fortunately we only ran it for a minute at most, so it survived... at least the important bits did... like the block, heads, rockers and er... that's about it..!

Any advice appreciated. I've screwed a Cleveland together before and it went great, so I'll be doing all of the build apart from machining and cam bearings.
 

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Nick, what are you doing for a crankshaft?
I don't think it would be too easy trying to find a good one around Australia.
Just a thought. If you are thinking of going to alloy heads in the future, and you are needing to find a crank now for this build, then why not think about something like a 445 stroker kit? That way you'll have the whole rotating assembly ready to rumble.
 

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Discussion Starter · #3 ·
I have a 2U crank in the shed, with matching rods. This is the only reason I'm not going mental right now. If it checks out OK, then I'll proceed with it. Otherwise, a stroker kit is an option...
 

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My first and only build was a 390. Bored +.03, used HP pistons and iron rings, clevite bearings, stock cam. Left the old cam bearings in, just flushed out the passages using a turkey baster. Measured the crank and rods myself and decided to use them as is. Cleaned the engine myself. Can't go by one build, though.

I was asked by the machine shop if I wanted line boring, flat topping and torque plate boring but I had read plenty of old hands who say the FE rarely needs that kind of work. Well, maybe if you are looking for 500 HP you could do it.
 

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Discussion Starter · #5 ·
I think I've decided on what I'm going to do in regards to machining. Turns out it was a 352 block as it doesn't have a 4.05" bore and I hear that underbored 390 blocks are quite the rarity...!

I'll get it bored to 50thou over to make a stock 390 bore, after an acid bath and removal of the cam bearings. Then they can put the new cam bearings in. The crank and rods will join the block in the bath, and then the former will be turned to whatever undersize it comes out at to make good; I hear they're good for 50/50 at their limit, so I'd probably get away with 20/20. Rods will be checked thoroughly, and if necessary, closed and honed. But only if necessary.

And then I've got a $1,000 order in the cart ready to go with Summit. And at that stage I'll decide whether to get a pair of Edelbrock Performer heads as well - I'm tempted to leave them for the moment as the heads I have appear sound and serviceable, provided the springs can handle whatever cam I end up with - it will be mild.

I'll dummy assemble the bottom end to see if the block would benefit from decking, but I'd rather not. Stock 390 pistons should bring me 10 to 1 compression so unless the heads have been skimmed, everything should button together easily.

In any case, I should end up with getting on for one hp per cube, more if I get the heads.
 

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Springs are cheap, and alot of guys change them out even on a new set of E-Brock heads. Were it me, I'd take the heads apart, lap the valves, debur everything, check stem clearances, then re-assemble with NEW seals and (maybe) new springs, and call it good. Don't know the specs on that cam but I think 390 HP would be a pretty big stretch with everything else mostly stock. Besides, you need low range torque anyway so don't get too caught up in how much HP you (think) you have. Double check (sonic mapping) that you can bore the block that much, too.
 
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