I picked up a 318 2bbl 727 combo from an 87 b150 van. Ran good with relatively low miles. Just wondering whats an easy way to get a few more horses out of it without destroying economy. I've never done much work on dodges in this manner, but I've been told in these particular years the 318 has lower compression than the older models. I've also been told it's hard to tell the 318 from the 360. How can I be sure it's actually a 318. I've ran a couple of 360's years ago and they couldn't pass the gas pumps. I'm strictly low budget here so any advice would be appreciated.
Ah, the lowly 318, the Rodney Dangerfield of the small block V8 world. Most people always lust for 340s or go for 360s, and think of 318s as dogs because nearly all 318s started life as low HP bread and butter motors. Fact is ALL LA heads start off with the same valve inclination angle used for better breathing in some of the so called race heads made for SBC, and the stroke (3.31) is only slightly greater than a 327 (3.25) with it's reputation for high winding HP. Admittedly you give up tenth of an inch of bore, but the slight stroke increase should more than make up for it. Most advice I've seen centers on find a pair of pre-magnum 308 heads from an early 90s Dodge pickup, adding in a Thermoquad carb and intake (GM Quadrajet would work) and decent cam/exhaust. Lockup 4 speed OD 518 trans from 91 or so helps, too. Go to moparaction.com and look in the tech section. Take the time to read the Q and A archives. Lots of info on the right heads, cam, etc., to wake that 318 up and these guys like the low budget approach.
the bore on 318 is is 3.19 in. - 273 is 3.625 - 340 is 4.04 - and 360 is 4.00 if your looking for factory hp locate a 4 bbl intake from the thousands of old police units around in junk yards - they breath well , cheap- I like cheap -these intakes came from factory from 1978 on. Headers free up the other end . Alot of mopar guys like the 273 crank ( same stroke ) stronger forged steal like the 340( same stroke ) --- 400hp is not out of the queation and will maintain some milage- jaxx
Just like any other engine, a good choice of cam, good intake and carb, and free flowing exhaust wake that puppy right up. No need to dig further. It will surprise and shock SBC owners at what so little will do for that motor.
Spend the $25 and get a copy of MotherMopar's engine manual. The absolute best reference book you can have for a Mopar engine.
I ran a 318 for years in my old 55 f100...it had the 904 tranny but thats just 3 speed too. with a 2.73 rear it got about 20 mpg. It had a mild cam,edlebrock intake and carb and stock exhaust manifolds. When I wasted that engine running my flamethrowers too much I put in a 360.....ssshhhhllllurped the gas at about 14 mpg and I hated it!
do a search on the moparts.com forum, should be around 1 billion 318 builds. Can you find a casting number on the heads? the late 80's 318's in the cars had the 302 heads, my guess is the vans did too. easiest bolt on HP is ditching the leanburn 2bbl for a 4bbl carb and intake, you'll need a new ignition to go with that. You can go mopar performace, FBO, or I bet if you search the moparts forum you can find how to make your own out of salvage yard parts. might also search the allpar forums, key word being leanburn. that way you'll find all the leanburn removal posts. there's plenty of performance parts available from places like summit, I know the cars got roller cams in 85, I think I heard the vans/trucks didnt until 89.
Most excellent advice! And you don't even need to be a Mopar nut to benefit. Grab a Direct Connection chassis manual too, if you can find one.
Some more bookwork if you're up to it. HP Books; How To Rebuild Small-Block Mopar Engines, and How To Hot Rod Small Block Mopar Engines SA Design; How To Build Big-Inch Mopar Small Block Engines Admittedly, not all this info will apply to your situation, but I picked up copies of these at a local bookstore used for under 10 bucks apiece.
The 318 is a fine motor. I had one in a '71 duster. Totally stock bottom end, MP "purple" cam, el-cheapo headers, $50 used intake, Holly 600, MSD box, replced the 3 speed with a 4 speed, and 3.73 gears in the 8 3/4 rear, and it was every bit as fast as any muscle car I ever owned. And I owned a lot of them. Economy was never very important to me back then, but I do recall it was much more efficent than the 455 buick GS I replaced it with.
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