Would you get a 390 for $150?

personally i would leave the 390 where it is, and build your 408 stroker motor. either motor will make the 500hp that you want, but the 351w motor will be lighter, and parts will be easier to come by.

I would choose the 351W every time.

gzminiz said:

I was originally going to do a 390 in my 67 but price made me reconsider and figured I would do a 108 stroker. But that is a killer price for the 390. It is completely apart and cleaned and never been bored. I will mention that I do have a 351W block sitting in my garage that I got for free. I have taken it apart and was planning on cleaning it up soon. Figure I could sell that for $150 (you think?).

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I also have a freebie 351W, but mine is a late '70s std bore shortblock and my car isnt set up for a BB already. $150 seems to be the going rate for a bare, rebuildable 351W block.

I think the costs will be a wash or actuallu higher for the 408. You already have the whole 390 and the car/parts it came with, so there is no conversion to do. Assuming you have a manual, you'll need either a funky pilot bearing or a smallblock input shaft. Changing the input shaft means a Toploader has to be pulled completely apart. You would also need a smallblock bellhousing. Headers, oil pan, engine mounts, clutch linkage, and flywheel/flexplate are all different. I think the nickel and dime stuff will really wreck any possible budget.

That's a pretty good price for the complete 390, but I'd get casting codes first and pics of the block or if you can look at it. If you look down the bananna slots at the front and rear of the head mating surface and see 428, then you have a block that will likely go to a 4.13 bore. Having an A or a C scratched into the rear sand core (will look like the letter has been welded on the rear of the block) is usually indicative of a 428 block as well. You need head casting numbers as well. Some of the heads will flow better than others and you need 14 or 16 bolt holes in the exhaust flanges or at least have the provisions to drill and tap these locations if nothing else, so early heads won't work (you have to use the diagonal bolt pattern, not the top and bottom pattern on a Mustang). If the heads are C6AE-R's or C80E-N's, they are worth some money to the SS guys so you'd be halfway to a set of aluminum Edelbrocks or even most of the way on a used set.

A dressed out FE only weighs 60-80 lbs more than a fully dressed out 351w.

A stroker kit for the FE will run about $1600 for the crank (cast) , rods (H or I beam) & pistons (hyper or forged) which is about the same as a 351w kit. The block needs no notching with the 4.25 stroke crank and if you buy the Pro Gram Engineering cross bolt main caps, you can have your block machined and be just as strong as a 427 block. These can typically go in a 390 to about 445 cubic inches. That bottom end would be pretty safe to 600hp.

C8AE-H heads are pretty common and can be ported by a couple of knowledgable guys for pretty decent price that will flow well (Scott Vincent and Les Schmader). An RPM intake is a nice dual plane intake that can be made to flow really nice. The Victor intake is a good single plane, but for some reason, they always need a LOT of work to run good. It's not a bolt on and run intake, it MUST be ported and sometimes decked as the valve cover rails aren't always level to the heads.

The stock rods are up to the task as well. Several companies make nice roller rockers and you can lose with the stock shaft system. There are some oiling mods that need to be done to the block, not expensive but detailed and consume a little time.

I'm planning a budget 390 performance build without a stroker kit that I'll detail out one of these days as it's built. It'll have ported iron heads, an aluminum dual plane intake, solid lifter cam, roller rockers, prepped stock rods and higher compression pistons. Cam, rockers, intake and pistons may even be used (and I hope they are). I'll have it dyno'd when it's done. There will be no swapping of headers or carbs, just get it in it's best tune and run it.

Oh, a 428 crank will also work with a set of 410 pistons IIRC.

Man, I am a retard. I thought he already had a 390 equipped car. I stand by what I said as far as cost, though. If you aren't set up for either one, it will cost about the same to outfit the car with the parts for one or the other.

$150 for a complete rebuildable 390 is good price. They also have the benefit of smaller crank bearings than a Windsor if you want to spin it. I may even do up a 390 as my next engine when the 302 is toast.

Its kind of like trying to choose between a 351W and 351C.

If your car is a small block car, go with the Windsor. If it's an original big block car, do the 390. Reason I say this, is it's a pain to round up the parts for a big block swap for a small block car, you've got half the battle won if it's a big block car with all the pieces.