318 ----> 360

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soaringcowman

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hey everyone, i'm swappin my 318 to a 360. all i have is the block crank and heads for the 360. so i was curious what all will swap over from the 318? and whats some good combos for pistions and rods, intake and carb, and best way to build up a pair of stock heads. thanks
 
Hello, In reference to your proposed eng swap, I would not go for a 360. Why? The 360 engine is good for a boat anchour.
I would stick with a 318 and build it up or go for a 340. I really think you would be much happier in the long run. The 340 is strong and takes a beating without falling apart ( as long as you take care of it). ie, don't overrev it without a load, use really good pump gas (Chevron, Shell, Texaco) no jack-pot, AM-PM, or discount gas. Use a synthetic motor oil like Lucus, Mobil 1, etc.
The 340 has far more after-market goodies available than the 360 ever thought of.
As always, this is an opinion ( I know-opinions are like noses, everybody has one!)
In supporting my opinion, I have 15 years experience in the auto body repair trade - I have worked on all models of cars, trucks, suv, full-size, compact, foregin, domestic. I have personally owned Ford, GM, MOPARS at one time or another in my life (I'm 66 now). For my money, Chrysler Corp. is the only way to go! I now own, a '98 Dodge Dakota SLT x-cab (bought new), and a 2005 town & country limited van (bought new, traded a 2003 t & c van in for the 2005), (I'm also handicapped now). So much for my opinion.
Kindest Regards,
Rick Fletcher
 
I have to agree with Rick unless you have a mgnum or even use the mag heads on the 318 or 340. the 318 's a little work horse.
fastcud1
 
Here are some numbers to chew on. I used Comp Cams Cam Quest and all I did was change the size of the motor nothing else. Same carb,cam,heads,compression raito etc....

318 Pk HP 373 @ 6000rpm
Pk TQ 379 @ 4000rpm

340 Pk HP 376 @ 5500rpm
Pk Tq 399 @ 4000rpm

360 PK HP 376 @ 5500rpm
PK Tq 412 @ 4000rpm

360 Torque is higher than the other motors because of the longer stroke and HP is about the same but the 318 will have to spin at a higher RPM.
 
just out of curiousity why isn't the 360 a good motor? i have been seen fellow board members getting pretty good numbers out of them? i'm some what a newbie to the mopar motor scene. so anything and everything will help teach and educate me more. now could i stroke my 318 with my 360 crank? how would that work? i would love to have a 340 but i can't seem to find them very cheap around here right now. and i need a solid running motor here pretty soon. i've got a 12 second dodge stealth i might have to let go so i want the duster to be some what close to this. at the moment i've got a 8 3/4 rear end with a 489 3rd member. i just need to get a suregrip set up and gears and it's done and have a few leads on a 727. so what ever i can do to get to what i want would be awesome without busting my walet all to bad
 
340s are for the numbers matching crowd. You can build a 360 for the same cost, (if not mabe even a little cheaper) with about the same horsepower and more torque. Yes, back in the day, 340 was the way to go. (mainly because there was no aftermarket or performance parts available for 360) But now the aftermarket has more than come through with parts and you can get more than enough parts for the 360. you can get a complete 360 out of a junkyard to rebuild for 100 bucks, compared to 500 bucks for a complete 340 that needs a rebuild.
 
wanta68cuda said:
Just remember the old saying There's No Replacement For Displacement!
Click to expand...

Very true.

I replaced my tired 273, with a 318 I rebuilt.

I added #302 heads, a Mopar .430/.450 cam,
dual exhaust off the stock 273 exhaust manifolds,
and old Edelbrock LD4B intak, and a # 1406 carb.

:)
Lee
 
:thebirdm:
I don't know what planet some of you have come from, but with the exception of the crankshaft and oil pan, the same speed parts off a 340 fit a 360. Here's the ONLY rule you'll ever need to do any small block Mopar correctly: "I AM NOT BUILDING A CHEVROLET......................!!!!!"
 
Dago Red said:
:thebirdm:
I don't know what planet some of you have come from, but with the exception of the crankshaft and oil pan, the same speed parts off a 340 fit a 360. Here's the ONLY rule you'll ever need to do any small block Mopar correctly: "I AM NOT BUILDING A CHEVROLET......................!!!!!"
Click to expand...

I second this motion and have built both.
 
Well guys, I'm not sure where you're getting your information, or what experience you've had with any or all of the 3 engines mentioned, but the statement "The 360 engine is good for a boat anchor" is totally out to lunch. It is one of the LA engine family, the same as the 318 or 340, and as such, performs the same as the other 2 in keeping with the parts and machine work used to build each. Given that the 360 has 42 cu. in on the 318, and 20 cu.in. on the 340, it's simply a matter of basic math to see where the street power lives.
 
phew that was a close one, i about throw my 360 overboard to hold my ship still lol. so let me get some opinions from you guys on pistons, rod, stock head setups, intake, and carbs..............

thanson_mopar the sn was just a random thing i came up with lol.
 
Rick Fletcher said:

The 340 has far more after-market goodies available than the 360 ever thought of.
Click to expand...


LOL Thats a good joke, Certainly with your 15 years of AUTO BODY EXPERIENCE you knwo that besides the crank, oil pan, pistons and rings they use all the same parts. Only difference is the main journal sizes and the cylinder bore.
 
AdamR said:
LOL Thats a good joke, Certainly with your 15 years of AUTO BODY EXPERIENCE you knwo that besides the crank, oil pan, pistons and rings they use all the same parts. Only difference is the main journal sizes and the cylinder bore.
Click to expand...

he just must be thinking of the max wedge hemi DOHC 360, which of course is way different from a 340 wedge:snakeman::toothy10:
 
AdamR said:
LOL Thats a good joke, Certainly with your 15 years of AUTO BODY EXPERIENCE you knwo that besides the crank, oil pan, pistons and rings they use all the same parts. Only difference is the main journal sizes and the cylinder bore.
Click to expand...

That's what I wondering. Finding a 340 block is the hard part.
 
I'll chime in too. As has been said, the 360 is almost EXACTLY the same as the 340 and 318; to choose a 340 over a 360 is throwing away an extra 0.27" or so of stroke and lots of money.
 
Mr. Fletcher must be a Chevy/Ford guy that has just joined to rial up the troops, it's obvious he doesn't know his mopars, so disregard his comments.

Anyway, back to the original question. The front timing cover and water pump swap over. The valve covers swap over. You can use the 318 rods but if it's a 60's vintage motor they are not as strong as 360 parts. If it's a 70's+ 318 then they are the same. If your goal is under 400 HP there is no real need to upgrade beyond stock 360 rods. Again as long as you are not shooting for big power or plan to use more than a 100HP shot of nitrous Keith Black KB107 pistons are a good economical choice.

The 360 is an externally balanced engine so you can not use the 318 harmonic balancer, but all the accesory pulleys and such will swap right over. If your car is a standard you can have the flywheel drilled for the 360 balance and if it's an automatic the easiest thing is to get the B&M 360 flexplate and use the torque converter you have.

The 340/360 block has different spacing on the drivers side motor mount ears but you can use the 318 mount if you make up a spacer that is 1/2" thick to make up the difference.

I would have the block's deck machined to put the pistons at zero deck. This will allow you to get to around 9.5:1 compression with open chamber 360 heads. Magnum heads that were mentioned will allow you to obtain 10.6:1 and will still run on middle grade gas with the ideal quench offered by the closed chambers.

Assuming you don't have a four barrel intake on the 318 most any dual plane intake with the 340/360 size ports will work just fine (with the exception of very early 273 heads and magnum heads all intakes will fit but the 273/318 have smaller ports than the intakes for 340/360's). The Edelbrock RPM and RPM Air Gap are arguably the best dual plane. Assuming your intentions are street performance a carb around 650 CFM will be the ideal choice. I am using a Holley 670 Street Avenger on my 360 and it's a super carb and would be a great choice.
 
thanks for all the awesome info dgc333! i am wanting to build a 400-500 horsepower motor, what would be a good cam for this set up? should i just get the heads rebuilt back to stock? or maybe get better valves, springs, and rocker asseblies to achive numbers like this?
 
soaringcowman said:
thanks for all the awesome info dgc333! i am wanting to build a 400-500 horsepower motor, what would be a good cam for this set up? should i just get the heads rebuilt back to stock? or maybe get better valves, springs, and rocker asseblies to achive numbers like this?
Click to expand...

to achieve that kind of horpower youll have to have a lumpier cam(that will still be streetable), some port work with the heads, definitly the 2.02 inch intake valves instead of those smaller 1.88 360 intake valves. Not a hard task to hit over the 400 horspower mark with a streetable 360
 
Getting to 400 HP is not hard at all and can be done with mostly factory parts but getting to 500 HP will require a very stoutly built bottom end some extensively ported stock heads or after market heads. It will require a cam that does not fall under my definition of streetable.
 
If you decided to stay with the 318. Heres a good upgrade or build.

Bore .30
Square deck the block, or save the money and use Mopar thin head gasket.
KB167 pistons
moly rings gapped to KB specs (this is important!)
Comp extreme cam 262 or 268
eagle I beam rods
and your 360 heads (worked) 3 angle, bowl blend, port

You would be suprised at the result!! This will also be set for the juice,(with different gap) i belive 150 shot. Im a 318 guy, and i love that moter.

As for the 360 being a boat anchor? well thats bull.
 
soaringcowman said:
thanks for all the awesome info dgc333! i am wanting to build a 400-500 horsepower motor, what would be a good cam for this set up? should i just get the heads rebuilt back to stock? or maybe get better valves, springs, and rocker asseblies to achive numbers like this?
Click to expand...

gooday soaringcowman from oz, there's a build in a ozzy magazine were
a bloke drag races a 360 with j heads ported ,you'l need your better valves springs about 238-260@ .050, .525-.575 lift 106-108 lobe centres ,single plane,400 is easy ,500 a bit more radical ,i'll dig up mag to get more particulars-ken ,back again 500hp is pretty bloody radical with j heads magazine article says dynoed at 505 hp run 10.2 in 1/4 . cam
[email protected] 12.5 comp ,so he's spent a bit of money and turning it to
8500rpm, go with streetable [email protected] cam 525-550 lift pocket ported-did you know that the cost of reconditioning heads completly
is probably the same cost as buying new better flowing heads complete
i built a budget 318 in oz with 360 crank makes 340 cube ,and used the 318 heads, single plane afb carb- torque monster mid range- i was impressed for a small block streeter,so if your 318 heads are in good condition thats an alternative-ken
heads
 
i've found what i think is a pretty good deal.....a guy locally is selling a 1982 360 out of truck. it's been fully rebuilt and zero miles on it. he said he had put a rv cam in it. it also come with 2 727, one in fact is good and the other is unknown condition. all accesories for the motor and tranny. with a brand new radiotor. all ready to drop in for 750
 
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