need advise in a 318

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100 mile

100 mile

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hey there, this is my first mopar build (allways WAS a bow tie guy) i was doing a 74 valiant but after pulling back the roof fabric to find all the cancer arround the windows, i found a 71 dart so now the valiant is a good donor. I have a 318 in the valiant (not original so i do nt know what year the motor is) the dart has a 318 minus the intake, and i have a 318 out of a 1980 camper van, my question is is there some web site that i can cross the block numbers to find out which one is the best to build. another question is being on a budget what can you do to get a decent amount of power eg, i want to rebuild it so my idea is bore .30, new cam (any sugestions), port the heads (depending on how much, and what to do), that kinda stuf, any ideas would be good.

here is one more, is there a 4spd auto, or 5 spd standard for a 318, i dont ever remember seing one.

thanks guys, as i say im new to mopar.
 
Any 318 made from 71 through 86 is basically the same. Heads all flow similar, same cam, same 2 barrel intake manifold (except for a few 4 barrels used in the mid 80's and on cop cars). Before 71 they were higher compression, about 8.5 to 1. After that they are pretty low compression, about 7.8 to 1. Note, the books say their higher comp than that but if you pull one apart and measure it you'll find it's almost always lower than rated. 87 up used a roller cam, or at least I think that's the year they started using roller cams. Some time in the 80's they started using the head casting 302. They are a better flowing head than previous yrs. and are closed chambers so the compression might be a little higher. Not much experience with those yrs. so I'm not positive exactly what years they were used. If your just looking for a block to build on their all the same up to the roller lifter models. Just look for the block with the least amount of wear. Oh yeah, 92 up are magnums. Roller lifters, closed chamber magnum heads, a little higher compression. But they have a different intake bolt pattern so you need to use a magnum specific intake. They also oil the rocker arms differently than the older LA engines.

Here is the only website I know of that has a bunch of info on small blocks.

http://www.moparts.org/Tech/Archive/smallblock.html

Hope this helps.
 
Most of the info above is right on. All 318 heads are closed chamber though, not just the 302's. Pre-'72 318's should have a forged crank, so will most truck 318's. Most of the rest are cast. But other than that they're pretty much all the same. Compression changed a little, but if you're rebuilding it won't matter.

For a rebuild, up the compression. 318 pistons are notorious for being further below deck than they're supposed to be, so check. 302's are good heads, but stock magnum heads ('92 up smallblocks) flow better and are also closed chamber. You'd need a magnum bolt pattern intake and oil through pushrods and lifters to convert over, it's covered here already. But get your pistons close to zero deck, your compression between 9.5 and 10:1, with stock magnum heads, a good cam and headers and you'll be over 300 hp without trouble.
 
Thanks for the correction Brian. I don't have much 318 experience and thought most of the heads were open chambered like 360's.
 
No problem! All my cars have 318's from the factory so I've picked up a few things. The chamber size does vary quite a bit still even with them all being closed chambered. Anywhere from 57 to 65 cc's is possible depending on the year and the casting, although the large majority should be between 60-63cc's.
 
100 mile said:
which one (318) is the best to build. another question is being on a budget what can you do to get a decent amount of power eg, i want to rebuild it so my idea is bore .30, new cam (any sugestions), port the heads (depending on how much, and what to do), that kinda stuf, any ideas would be good.

here is one more, is there a 4spd auto, or 5 spd standard for a 318, i dont ever remember seing one.

thanks guys, as i say im new to mopar.
Click to expand...


Alot of "What to do to a 318" is depedent of what you want out of it. As stated above, any 318 is a good 318 so long as it checks out. Of course, things like keeping the overbore to a min. and straight cylinders, uncracked heads, etc....... all add up to a better strating point.

Think of a 318 as a smaller bore 327 and build from there. The same basic princapals apply. Things of note that the MoPar has over a Chevy engine would be;

The abilty to use quicker lifting cams. The rate of which the 904 lifter can obtain in quickness of lift is greater than the smaller Chevy .842 lifter can get.

18* valves in the head offer an advantage over the 23* head. However, the actual flow is what counts.

The cave eat of MoPar engines are few. Weird things like wacky pushrod angles. (MoPar corrected this in there race blocks.)
Heads and intakes cost more, but then again, anytime you go up in performance, it costs more. And sometimes, you barley get more, LOL! That applies to every make of engine really.

Your 318 is internally balanced, Keith Black has a zero deck piston. I think it the 399 HyperUtechic. (SP!?!?!)
Head cc amount is important to the ratio.

What is the goal? E.T.?


MoPar does have a 4spd auto. Based off the 904 is the A-500. This may be difficult to install since it is longer, has a different location for it's mount and is beefier in the tail since the company took a standrd 904 and added on a overdrive unit. They basicly removed the tail section and installed the O.D. in it's place. You'll then need to shorten the driveshaft.

A 5spd manual is easiest to get in the form of a Tremec in a kit. There are various companys offering this conversion kit. It can get pricey, but! Everything is brand new. New pedals, linkages or Hyd. clutch lines, fly wheels etc.... everything new. Even the trans mount. New new new.

Click here for 1 such company; http://www.keislerauto.com/
 
Yes on both. look for an A500 trans out of :
# 1989-2001 Dodge Ram pickup 150/1500 V6/V8(2WD)
# 1989-2003 Dodge Ram Van B150/B250 V6/V8
# 1989-2003 Dodge Dakota

1998 Dakota came with a 318/5-speed and a few other years. Either 318's would be fine, but the older one might have more meat in the bore. Hard to tell, but you can weigh them and take the heavier one. Go with 302 casting fast burn heads and clean up behind the valve seats. Should give stock pistons a little boost in compression. Run a conservative cam, not too big or youll kill your bottom end. Isky 268 is about max for a stock convertor, 5 speed cam go a little bigger.

PS. Not all 318's are closed chamber. The 318 302 head is closed as the actual chamber is smaller than the footprint of the piston, ie if you surfaced the head, the chamber would look like a heart, not a circle. all other 318 heads are open, circular chamber. There is a quench area away from the valves, but it still is technically an open chamber. The 273 "920" head was closed too but I think they were the only closed heads.
 
thanks guys, alot of good info, as soon as i get the dart to the house ill send pictures of both and progress there-after, im sure ill have more questions the further i get into the drivetrain end of things. actually whats this i hear of a "mini tub" i get moving the leaf springs to the frame rails, but to run a 10 or 11 inch tire will that be enough????????
 
Yeah mini tubbing is popular cause it's not real hard to do and you can run wider tires that way. I assume you mean is a 10-11" tire enough for what your planning? I'd sure hope it is. I have seen many guys run 8" wide tires well down into the 11's no problem. Their are even guys in the FAST class running 9's on stock size tires but of course they have done every little trick to the suspension possible. The big thing is the type of tire. Run something sticky like a drag radial and you'll be surprised how well it hooks. A slick is even better.
 
k i just pulled the motor out of the campervan i have at the house and im kinda stoked (i think) i crossed the numbers of a mopar website and it says that it is a race engine ( 4104230-318-4 ) they say its orange but this one is blue, do i have something or am i just blowing smoke??????
 
Mopar may have used the same casting number for the early race block. If I remember right they were stamped as being a 318. Maybe that's where the confusion came in. The chances of it actually being a race block installed into a camper van is about as good as finding the proverbial needle in the haystack. That doesn't mean it isn't a good engine by any mean. The 318 is one of the best engines ever produced by any company IMO.
 
Depending on how much it costs to clean up a set of 302 heads, oversize valves and good springs you might want to look at RHS or Iron Ram heads by hughesengines.com depending on what your'e shooting for newer heads might be better. 5sps might be able to find one from a dakota or half ton. Look for a NV3500, the heavy duty version has a low 4:1 first gear, the id tag is stamped on the left hand side, there is a light duty version as well. Good luck and have fun
 
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