318 build

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I'd like to see your dyno slip after it is built and then you can tell us if they lied or not. A lot depends on who you ask if the rag's lie about there builds or not. Some say the rag fudges the numbers so the parts look good for the advertisers. I myself do not believe that, but often wonder about the dyno numbers themselves.

Boring a block should only be done to clean up the cylinder(s) for the new pistons. On a 318, an added bore of .030 only yields 4.9 cubic inch's. (318.2 to 323.1) That ain't nothin in a build.

Less boring of the engine is better for a stronger stiffer less flexing cylinder wall for more power due to best sealing. Not that going .100 over on a 318 will kill it. (*Well, maybe, sonic check it first!* ) But boring out an engine is equaling less life due to less rebuilds in the future.

If you need to, then fine, but, IMO, don't do it for 5 cubes, do it only because you need to do it. 5 cubes won't make a difference.
 
There are a TON, literally a TON, of threads related to 318 build ups on this site. And the 400 hp 318 in the HRM build up has been discussed numerous times. Do a search and you'll see what I mean.

Can the engine in the article really make 400 hp? Probably on the right dyno. I think the numbers are a little generous, but not over the top crazy. I know I wouldn't want to run a used timing chain and mill the crap out of the heads to get the right compression on an engine I wanted some longevity out of.

Can a street 318 make 400 hp? Yes. Especially with the RHS heads available now. Even switching over to stock Magnum heads will net you much better flow than the stock 318 heads.

So, are you rebuilding 318? Trying to juice up a used one? Budget?

The biggest issue with the 318's is the lack of compression. Stock compression specs were bad enough, and the actual compression ratio's are often lower. If you're rebuilding, aftermarket pistons and zero-decking the block solve the compression issue. If you're not rebuilding, you'll have to get more creative.

But the article points out the basic formula-

Compression up around 9.5:1
Better flowing heads
cam
intake
carb
headers

Mopar Muscle did a similar build on a 318 here

And seriously, look in the small block section of the forum. Or search 318 build, magnum heads or magnum head conversion, 400hp 318, etc...
 
RHS heads would be great, could get some reproduction 360 heads with 1.92 or 2.02 valves from www.aeroheadracing.com but would have to get taller pistons to counter the larger chamber to get the compression up. Good luck
 
yeah i was planning on reproducing the build's parts and go to the junkyard and just get the 360 head cores
 
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