need help with 318 build

[bigrog34]

Ok I have a 72 318 and want to produce 350 to 400 hp. Need help with parts, I want to keep the motor looking almost stock.
What heads springs valves lifters cam crank should I use.

 

[Coronet 500]

This should help: http://www.hotrod.com/howto/113_0304_318_small_block_build/viewall.html

 

[Coronet 500]

Larry Shepard's HP Book is very good, here is some more good reading.
http://www.allpar.com/mopar/4bbl.html

http://www.allpar.com/mopar/LA-V8-engine-head-swaps.html

 

[Satellite65]

I'm not a small block guy so I can't answer your question directly but I'll say this:

I'm sure it can be done and has been by a lot of people, but any time you get past the 1hp/CI mark you're not talking about a typical street performance build. That's when engines begin to get a little tempermental. To get 350-400 hp out of a 318 means you're going to have to spin it real fast. A steel crank, good rods and the lightest pistons you can get your hands on will be required. You're going to need heads that'll flow enough air to make that kind of power and a cam that'll work the heads. That kind of cam will probably want decent compression, deep gears and a loose converter.

I don't know where you're at as far as parts gathering goes, but if you could can the 318 for a 360 you'd be that much farther ahead in the game. On a typical street build, figuring at or about 1 hp/ci your looking at 42 hp just on displacement alone, all other things being equal.

Visually the 360 looks identical to the 318 and unless someone has X-ray vision they'll have no idea what's inside the block. If you don't have a crank yet you could stroke the 360 to 408, that's another (approximately) 48 HP right there.

Budget's another thing entirely. You may already have a complete 318 laying around. While you could use it to build a pretty stout street motor, if you're looking to get 350-400 horse out of it you'll find that aside from the block and some external parts there's not going to be much else you can use. If you lower your power level target you could save quite a few bucks.

The book "Mopar Performance" by Larry Schreib and Larry Atherton (S-A Design) is kind of old school (1978) but contains a lot of good information.

Edit: Of course, there's always nitrous!!!!

 

[rumblefish360]

This is an easy build and spinning it fast is easy with a short stroke engine. The target HP number is and will all ways be at the top of the RPM range no matter what engine your building. It is just long stroke engines make it sooner.

Take your 318, install a set of zero deck pistons, like from KB, machine the deck to equal the piston height and insure a zero deck.

Cam? Go with this, IMO it would be a great cam for a hot street car.
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=631&sb=2
360 heads rebuilt would be cheapest, 318 heads ported with 360 valves are pricey, but, highly effective and efficient. The heads will need a small machining to fit the Comp springs.

RPM intake, 650 cfm carb, headers, 2-1/2 exhaust pipe.

 

[shag766]

This should help: http://www.hotrod.com/howto/113_0304_318_small_block_build/viewall.html

another test at westech performance. these guys are good.:headbang:

 

[bean bandit]

I came across this article:
"318 engine build - a parts book 400hp 318"
http://www.moparmusclemagazine.com/techarticles/mopp_0409_318_engine_build/index.html

I think it's a very nice build. They use off-the-shelf, readily available parts. No excessive machining. Apart from the usual boring and honing and some line-honing, they zero-decked the block.

They used Magnum heads for their close-chambers and big valves.

This is a build I would consider my self.

Cheers, Remco