Hello,

I have a '76 F100 with a 360. I want to get a new engine, I was wondering if anyone had any suggestions about my options. I was thinking about taking it to a shop and having them put in a 390 to give me some more power. I was also wondering if the 360 in it now could be rebuilt and a new intake manifold put on it so it could have a 4 barrel carb. I also came across a deal where someone is selling a 351 (in parts) for $200- would that worth it to take somewhere and have them rebuilt it? I do almost all work on my truck myself, but a new engine is beyond my skills. I also have a limited budget so I was wondering what the best bang for my buck would be.

Any suggestions/advice would be greatly appreciated!

Thanks,

matt

 

390 would be a direct replacement or rebuild the 360. The 351 depending on which 1 would require new mount towers, & bell housing or transmission

 

360/390 use the same engine block, the bore is the same (4.05"), the stroke is different.

Stroke: 360: 3.50" / 390 = 3.78."

All you need to make a 390 out of a 360 is the 390's crank, rods and pistons. EVERYTHING else is the same!

351 is a completely different engine and there are THREE different types: 351C; 351M; 351W

 

Being on a budget, your best bet will be to stay with the same engine family and keep away from doing a swap.

Upgrading your 360 to a 390 is straight forward and uses factory pieces, again, more bang for the buck.

The FE family (360, 390, etc.) responds well to improved exhaust, a better ignition system and lastly to cam / intake and carb changes. Remember, if you can't get the exhaust out, or the fuel ignited, it doesn't make much sense to try to get more fuel in.

Lots of good ideas and thoughts from members here. Seems everyone has their favorite changes and upgrades, incuding me. On a 360/390 I prefer a good dual exhaust system with a cross over tube (2 1/2" headpipe, 2 1/4" after the muffler), a DuraSpark distributor triggering a MSD 6 box and a dual plane intake with a 600 or so cfm carb. For a cam, I typically choose a mild hydraulic grind, something from near the top of listings, and stay away from the 'rump-rump" pieces. Regardless of which cam you choose, use the components (lifters, springs, etc.) recommended by the cam manufacturer.

Define what you want and work to that end. Don't get sold on hype and ads. With that said, rely on the different manufacturers tech and help lines. They all want you to be pleased with their products and will help you choose the right pieces for your needs and combination of parts.

I have always found that for a daily driver, or a basic street driver, that less is better, especially when choosing camshafts and carburetors.

Good luck.

 

If it is simply 'not powerful' then you will get a big kick out of a few simple upgrades. My order of operation usually goes something like this:

1) Aftermarket intake & carby
2) Headers
3) Upgraded dizzy & coil

That'll give a nice bump over what is there already, and unlock the 'glass ceiling' from the next lot of modifications:

4) Camshaft & valve springs

Obviously if there is something wrong with the current engine then get that attended to, there is no point putting all that stuff on an engine that is worn and in need of a full rebuild.

- boingk

 

Thank you for all the advice! It sounds like my best bet is to find a good shop and have them rebuilt and upgrade my 360 to a 390. The engine is tired, its got about 100k miles on it so I am assuming it could use a full rebuild. That does sound like the cheaper option too.

 

Your 360 might not even need a rebuild. Have you assessed its condition? Compression test? Leak down test?

What is your budget??? Best bang for buck is headers n dual exhaust.. even on a 360.

Then a 4v intake n 600 to 650 cfm carb.

If ya want a.390, consider a short block from Carolina Machine Engines or ATK... but youll still have crappy oem FE heads unless ya go aluminum with Edelbrock Performer RPMs.

 

Yup, go for the three big tests an engine builder needs:

1) Oil pressure. What does it idle at cold? Does it drop a lot when hot? Ideally it will be fairly consistent. You want around 40psi or more at cold idle, and more than 25psi at hot idle. Ideally those figures will be up around 50-60psi cold and 40psi or more hot. Low pressure means worn bearings.

2) Cranking compression. An engine in good condition will see about 140-150psi, an older one will see about 120~130psi, and anything 110psi or less is fairly well worn. Low compression can indicate worn rings, worn cylinder bore, bad valve seals, or any combination of those three.

3) Leakdown test. This will determine if you have a particularly bad point in your cylinder. You hold pressure with an air compressor in the cylinder being tested and a special leakdown gauge. You can see by moving the crank if there are wear points on the bore that will need it to be rehoned or over-bored.

The first two are very basic and can be done at home. The last one uses a specialized gauge and is best done by a machine shop. Chances are, though, that if the first two aren't good then you'll be taking it apart anyway so the third one isn't that important!

- boingk

EDIT: For reference, I have a '78 351 Cleveland motor in my F350. It has 50,000 miles on it and is like new inside - no noticeable wear at all. You may have a good engine, just needs a good tuneup and some aftermarket speed parts. Sure woke my 351C up!

 

Cool, thanks for all the info- I am gonna take a look at the oil pressure/compression on my engine, and go from there as to weather I need a rebuild and upgrade.

Thanks,

Matt