Mopar guys--? on 318 horsepower

[George]

Obviously a 360 would be easier to build power with than a 318, & a 440 even easier, but the guy has a 318. 1st thing i do is toss the intake & carb. easy fast & simple. The rest can wait till I want to get nore involved.

[Fat47]

Thanks for the responses and the information. I had figured on a Preformer and 600-650 cmf with a mild cam. I don't need 400 HP----want a street/trip friendly and reliable engine. It appears the stock engines put out somewhere in the vacinity of 200 HP, give or take a little. I will need to buy new pistons anyway, so it appears the 8-1 could be raised to 9-1 with very little extra investment. With this mild build it appears I could be somewhere in the high 200HP range?????????

I will have to check the oil pan/rear sump issue relative to the front end upgrade I had planned. Any other advice/ideas appreciated.

[George]

Probably a Performer intake, cam & carb 600 CFM would probably do fine from your description.

[mbmopar]

Originally Posted by DonMan

There`s nothing exotic about the LA 318. It`s simple engineering and a very good, solid engine, no quirks. It responds to high performance modifications similar to a 350 Chevy.
Add a nice street cam, free-flowing exhaust, dual-plane intake and a 600 Holley and you`ll have a great 300 hp engine.
The stock electronic ignition is excellent and reliable. Don`t try to get fancy with anything and you`ll be fine.
Mopar Performance ( Direct Connection ) offers some nice camshafts for this engine. An Edelbrock Performer intake is a good choice.
Late-model 360 ( 5.9 liter ) heads are an OK upgrade.

It all depends upon the power level you`re shooting for.

yeah, pretty much what donman said....basic building block engine, no pun intended

[41 C28]

I,m running a bone stock 318 2bl with a 904 in my 48 Dodge coupe, only mods are dual exhaust and Pertronix ignition. I would like to have a little more power but the car runs good and is simple. I'm not looking for a race car.

[storm king]

Horsepower is not what you should be looking for on a street engine. Torque is what moves you. High winding small blocks can make big H.P., but usually only at very high RPM. The 318 is a good torque motor. Purple cam, good four bbl and aluminum intake and you're set. Screw H.P. #'s.

[6mopar7]

I had a 1969 Sport Sat with a 318 & 2-bbl for many years & it had ~230 hp in stock form. I did have trouble with the stock intake's heat runners stopping up twice. The valve guide seals leaked as the miles piled up, be sure & check them if you keep it as is. Loved that car, wish I had keep it.

I would do as another poster suggested; go with a Performer intake & 600 CFM carb (with electric choke).
Maybe add an electronic ignition. As I remember the 318's had rear mounted distributor so firewall clearance might be an issue?

Good luck on your build!

John

[MoparMan4GZUZ]

this thread comes at a great time for me. I just took my 68 318 into the machine shop to get hot tanked and have the bore checked. it is an original 49k motor. I have a set of 1984 police special heads for it with the police special 4 barrel intake with a quadrajet carb. I will be keeping an eye on this thread to see how this build goes compared to mine. I have both a 904 and a 727 for trans choices, I will probably go with the 727 as it also has 49k on it. Bud

[sckracing]

Fat47,

Here's my LA 318 (out of '74 Dodge Dart) sitting in my '39 Desoto.

*Stock pistons/crank
*Summit 360 perf cam/hyd lifters ($100.00 +/-)
*'98 Magnum big valve heads (Craigslist $100.00, and an impromptu sales pitch on how I could become a distributor for Mona-vie. Heads yes - sales NO.)
(Note: req's head specific-vert bolt holes-intake, AND, if you don't use roller lifters, you'll need to get longer "Oiler" pushrods-early 318's have solid pushrods)
*Edelbrock Air Gap dual plane manifold ($350.00) (not cheap- couldn't find a stock one to save my life, so ponied up the dough)
*Holley 600 ($60.00 - got a good deal on it via Craigslist-newly rebuilt)
*Block Hugger headers ($75.00)
*Pair of Speedway glasspacks ($120.00)
*HD water pump (NAPA $45.00)
*Stock Mopar electronic Dist
*Stock A-940 transmission (came w/motor)
*Custom built driveshaft ($200.00)

Had the same vision as you did Fat47, driveability-with some kick, keeping it as Mopar as possible (selling point down the road). Best guess HP is about mid-300's. Have not got it out on the road yet, but very soon.

[Desoto291Hemi]

Good combo,,,it will run great.
Did you raise the compression at all,,,,(deck the block or mill the heads)?
Do you have more pics of your ride,,,looks cool.

Tommy

[moparmonkey]

318's are great engines, and highly underrated by a lot of folks. That being said, 400 hp is not easy to do with a 318. At the very least the stock heads are too restrictive for that much power, so you'd need a ton of head work to get to 400 hp, with high compression and a big cam. It would not be super street friendly.

Stock the 318's made from 175-230 hp, depending on the year of manufacture. The later one's suffered from low compression and smog alterations to timing and carbs.

If you need pistons already that's a great way to add some power, and make sure you check your deck height before you decide what to get. 318's are notorious for having the pistons further down in the hole than the factory said they were, so some had really low compression. If you want to do better than the stock heads without spending the money on aftermarket look for 89-91 "302" heads. These are closed chamber heads with 318 size ports, and were found on trucks/vans with 318's in that period. The exhaust port design is the same as the performance W2 heads, and flow well even in stock form. They also made 308's in this time range, but they were for 360's and have open chambers and larger ports, which slows intake velocity on the 318's unless you're shooting for big power. The 302 refers to the last 3 digits of the casting # on the head. The nice thing about the 302/308 heads is that they are LA heads, not Magnum heads, so you don't have to worry about the lifter oiling thing changing over to Magnum heads.

A 318 with 302 heads, 9 or 9.5:1 compression with a performer rpm intake, 600 cfm carb, headers and a nice cam should put out a good 300 hp without issue (or more depending on how crazy you go with the cam), and still be very streetable. But without head work it'll be real difficult to get much more than 350 hp.

[50dodge4x4]

Horsepower. Everyone is concerned about HP#s. Its the torque you want on the street. 318s have great low rpm torque. Dual exhaust, even with factory manifolds, and a 4bbl carb & intake really wake up a 318. Add in a small cam, (with a working rpm range of 1500-5000) or even a factory style 340 cam and you bring to life a whole new critter. Keep in mind the actual rpm range your 318 will be running, most "improvements" only increase the working rpm range. The stock 318 heads and ports work well up into the low to mid 4,000 range (on a 4500-4600 factory intended red line), how often are you planning on turning it that high?

Real life experence: Stock 318 block bore & stroke, fresh rings & bearings. Stock 318 heads match ported to the intake and exhaust gaskets. A factory iron 360 4 bbl intake, factory 318/360 exhaust manifolds (mid- late 70s truck center dump) dual 2" exhaust to the rear bumper with turbo mufflers. Comp 260 cam, Mopar electronic ignition mated to a 904 and an 8 1/4 rear with open 3:55 gears (later changed to 8 3/4 with 3:23 open) in an all steel full fendered 35 Dodge 2 door sedan. Car could spin tires (255 60 x 15) at will from a standing start, pull down 20 mpg @ 70mph with power to pass and could run down the road with most anyone. We put 66,000 trouble free miles on the car in 6 summers, then sold it to fund the next ride. The hard core chevy guy that bought it was impressed with how much power the little 318 had. It was hard to convince him it was "only" a 318. Gene

[Racedad]

a quick reply...the 318 I bought from a friend was 50 bucks!!! two years and 8,000 miles later in my 30 ford 5 window Rat Rod !!! I dig it, being a chevy Dude, my friend forbid me puttin a 350 chev in it, hence the 318. I spent 450 bucks on a rebuilt 904 and new converter, DONT forget the Lokar kickdown cable, or you will burn up the trans.It runs Absolutely Awesome and takes me anywhere and always starts up , I swapped the intake and put a junkyard Q-jet on it. the stock cam has tons of torque!! Later "Race"

[440scout]

i have been a mopar guy all of my life, and have to disagree with the mp purple shaft cam comments.. although the magazines push them on most of their builds, i personally think they are the worst cam you could buy for any mopar engine .. i have tried them in a big block, small block , and even a slant six and every one of them was terrible on power. the best luck i have had was with comp xtreme energy cams and the crane cams (not the magnum cams, the dual grind series )
just my 2cents
doug

[warped welder]

318's are great for cruising and pep. my 67 fury has the one it was born with and it moves that boat around fine,with the 2 barrel on it and 21mpg. Same with the 37 hudson it runs a 73 out of a dart.The tranny to get would be a 727 torqueflite or overdrive out of a f-s pickup or a dakota.So cruising or hot rod it will work.

[moparforlife]

Originally Posted by 440scout

i have been a mopar guy all of my life, and have to disagree with the mp purple shaft cam comments.. although the magazines push them on most of their builds, i personally think they are the worst cam you could buy for any mopar engine

I'll second that. The purple shafts are old grinds, and there are a lot better, more modern grinds out there nowadays. I prefer Hughes because they are low duration, high lift.

[440Dave]

Most of the advice here is sound, the only thing I have to add is if you run across an old edelbrock LD4B intake at a swap or somewhere, they're an excellent dual plane that lends itself to what you are shooting for. They're basically a small port version of the well known LD340. The newer manifolds will flow a tiny bit better, but I'll bet the difference is not even measurable on a mild 318, and they can usually be had for 100 bucks or less.

[RacerRick]

400hp out of a 318 is actually pretty easy, and cheap!

Rebuild the 318 with a stock bottom end, exept for pistons and rod bolts. Get some KB's that get the compression up. Then go get a set of Magnum heads from a later model 360 Magnum, pocket port them, and bolt them on. They have 1.92 intakes, 1.60 exhausts and small chambers - you want to shoot for around 10:1 compression.

You will need to use AMC lifters because the later mopar small block oil through the pushrods, and the proper pushrods. I like to run roller rockers, and you use a standard small block hydralic flat tappet camshaft. I would use the Isky Megacam 280. You will need a magnum intake since it uses a different bolt pattern - i like something like a Performer RPM with a 750 carb, and headers.

Voila - 400 hp. There has actually been several articles about this combo. It works really well, and the late model Magum heads are key. It like putting Vortec's on a SBC.

Cheapest good running combo? Get a bunch of 340 parts and bolt them on - Cam, springs, timing set, intake, carb, and a set of headers. On an early 9:1 compression 318, this is an easy 275hp combo.

You can get about 350hp using the old style heads with the same combo.

[XxStrait-EdgexX]

Originally Posted by plymouth1952

the motor is like any other v-8 18436572. jokeing aside what is at issue is the starter location, that damn thing is in the way even in a fat body.
the 318-A- is a great mill but as said you will need a truck pan and pick up.
find a 273 and get the adj rockers and cam option gets better. if you go with 360 heads then you will need to use a 360 intake. 318s needs 318 intake they do change but the ports on a 360 are much bigger then a 318. also remember a 360 pan wont work on a 318,

Honestly, I was told by the guy that sold me my donor that it had a 318 in it.... I went out and bought a 4 barrel intake rear sump pan etc and then I ran the numbers and it turns out its a 360.... well all of the 318 parts are on my 360.... the only difference I was told is the part numbers.

[moparmonkey]

Originally Posted by XxStrait-EdgexX

Honestly, I was told by the guy that sold me my donor that it had a 318 in it.... I went out and bought a 4 barrel intake rear sump pan etc and then I ran the numbers and it turns out its a 360.... well all of the 318 parts are on my 360.... the only difference I was told is the part numbers.

Part numbers aren't the only difference!!! The oil pans are different, so I can guarantee you if the oil pan fit it wasn't for a 318, or you don't have a 360. One will not work on the other. 318/340's share a pan, 360's have a different sized radius around the main caps.

Intake manifolds will fit, but there are two different intake port sizes, one for the 318 and one for 340/360's. The intake will fit, but if it truly has 318 size ports they will be smaller than the intake ports on the head. This depends on the intake though, a lot of "318" intakes actually have the larger ports because the manufacturers are lazy and stopped making 318 specific intakes awhile back.

Other than that, 318's and 360's have a completely different bore and stroke, different sized mains, a different engine balance (318's are neutral, 360's are external balance), and the heads have different sized chambers and port sizes.

Figuring out which you have is easy on a mopar, you don't have to run the numbers as the displacement of the engine is stamped on the side. For example, my 340



As you can see, the "340" appears clearly at the end of the casting number on the driver side of the block.


Here are a couple sites with some good info regarding mopar engines...

http://www.mopar1.us/tech.html

http://www.mymopar.com/index.php?pid=31