400hp 318

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blackace

blackace

The KING of flats
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Was doing a Google search and came across this on Hotrod's site.

http://www.hotrod.com/howto/113_0304_junk/

What is your overall opinion of this?

I have never rebuilt an engine but have quite a few years as a Body Man. Would this be difficult to do for some one has never done it before?
 
Nice...now..do all that to a 360.......

..no replacement for displacement. Mine is only pushing about 9:1...but later when I get serious about it, I want to run it up to a good 10:1+ CR.
 
I thought this months Mopar muscle had a 400hp 318 build up using off the shelf parts and no special work on it ...i'll check
 
OUTLAW said:
I thought this months Mopar muscle had a 400hp 318 build up using off the shelf parts and no special work on it ...i'll check
Click to expand...

Not the entire build up. They ported the heads from that motor. Its the one in the link I posted.
 
Nothing wrong with doing a 318, its different. Lotsa fast 360's but it has that cool factor when its been done with less cubes. But I heard those build-ups wern't done with long life in mind. If you wanna make a 318 go fast I'd talk to Don at FBO Systems. His Barracuda runs a 318 in the 11's and survives
 
aa dont worry 318 are just as good as any mopar smallblock!
it just needs the same thing as all the other engines its missing compresion realy good heads intake carb and a good exhaust as built oroiginaly, my old 318 with lightly home ported heads using some of my 2 stroke skills from younger years a good cam some more compresion a set of headers and some other basic things where regulary kicking smallblock chevy but on the street! idled at 600rpm and where pulling hard all the way up to 6800rpm still with smallvalve heads... lots to be done to dose 318´s
its like a 340 it likes to rev high
 
Interesting reading..The HR 318 uses stock, re-ringed lower end, and "302" heads, to get 400+. The CC 318 was completely redone, doing the performance machining workrequired, using the latest design heads (new from MP) a larger cam, 1.6 rockers, and $4000+, to get the same numbers. (lower, actually). There are a couple of things glaring at me..Dulcich was a part of both builds, and he knows his stuff. Personally, I think the CC build was trying to get the Magnum MP heads sold. I also think the quality of the heads was clearly shown (poor out of the box,like the big block stuff). So where is the power? The HR article makes a short comment about how the 302 heads could be worked by anyone with a grinder. Not true. If you walked in with a set of core 302s, the new parts and port work would cost you more than a set of brand new Edelbrocks. Now, a similar engine, with basic gasket matching, and smoothing of the bowl areas (like the MP template kits) that could be done by a newbie, would still cost four figures, and probably make 320-360 horsepower with the same build. If I were doing a quikie job, the 302 heads, and properly matched parts, would be fine as a place holder. If I was going to spend $4K, I'd spend it on a 360. The 318 has identical stroke and rod length as the 340..so it gives up nothing to it besides 22cid. If the 340 is 425 horsepower, the 318 will make 405. Now, they have a kit for the 4" crank for the 318..I'm looking at that to go into my truck, so I dont have to do a big block conversion..
 
Its hard to take any magazine buid up serious, wich is to bad. Also gotta watch were they dyno them. Westech is a favorite of theres. There was a small write up in CarCraft a few months ago and I mean small so few people would catch it. westech Dyno was calabrated right and was reading about 5% high. I think they fixed it though. Its read 10% high now, LOL
 
ok i also dont like magazine buildups... there is a reason that they can build a stout engine every now and then and that is because they get stuff cheaper to write good things about them to let the manufacturers make money on the magazine readers.. but a healthy 318 is as good as anything and its not the dynod horsepower number that makes gearheads smile its the feeling when you drive, right? and you dont need a fixed number of horsepower to have fun what you need is an engine with the right atitude!
 
blackace said:
How difficult is it for someone who has never ported a set of head???
Click to expand...
As long as you dont go crazy with porting you should be OK. You probably wont make the power that they made though. Mopar Perf. sells templets to help you port heads without hitting water.
 
i aggree with adamR just remeber that porting is not about making the ports bigger its about making them more eficent
 
blackace said:
How difficult is it for someone who has never ported a set of head???
Click to expand...
the tricky part is keeping the bit moving so you dont create "peaks and valeys" in the runners and making the ports all flow the same here is where a flowbench comes in handy.
 
Well here is a question. In the article is states that they ported the intake ports of the 318 heads to the size of a 360 and put 2.02/1.60 valves in it. Why not just put a set of 360 heads with 2.02/1.60 valves?
 
because the 318 heads are the 302 small chamber heads. more compression.

steve
 
ill have some 302's for sale after i convert mine to magnum heads and efi.also maybe the hp 360 head from mopar.

steve
 
I 'm building a 318 ,magnum heads polished intake and chambers , smoothed exhaust R/T springs, KB167's, comp XE268H ,port matched cast '72 340 intake .

I decided to keep the 318 so I could register the car as an antique, avoid the state inpection and get cheap full coverage insurance.
 
frankwest said:
I decided to keep the 318 so I could register the car as an antique, avoid the state inpection and get cheap full coverage insurance.
Click to expand...

Can the state really tell the differance between a 318 or a 360 ? And if they can I bet they can tell the differance between a 3.31" and a 4" stroker crank.
 
i was thinking about building up the powering my 318 a bit to make it a street/strip car. The one guy i talked to about it told me to get a pair of swirl head off of a 318 made in the 80's. Then another guy told me to go with 360 heads. Which ones r better?
 
if you are going with a stock piston the 80's 318's have a small chamber which is more compression. just add 1.88 1.60 valves and some porting you will be good to go. i ran 14.77 with those heads stock with the stock cam. you should be fine, andi run 87 and have no ping

if you use the kb piston you can use a 360 head.

steve
 
Porting is more than just removing metal. Everyone can do it, but only some can do it right, and only some of those can do it WELL. 302s are the better cheap way out heads for the street. If this is a serious trip effort car, then the 360 heads are the better choice. The 360 heads will move more air, but you may not want that, and there are downsides to just bolting them on.
 
blackace said:
In the article is states that they ported the intake ports of the 318 heads to the size of a 360..... ...put 2.02/1.60 valves in it. Why not just put a set of 360 heads with 2.02/1.60 valves?
Click to expand...

Magazines and their BS articles. :banghead:

First, there is no way in hell they ported the intake ports on a 318 to the size of a 340/360 port, because the bottoms of the 340/360 ports extend much lower into the lifter valley than any of the shaft-mounted 273/318 heads ever did.
You can put 2.02-1.60 valves in a 318 head, but porting them to flow as well as the valves will allow gets you into water.

What few people understand is that making heads FLOW will net you as much, possibly more, power as concentrating on getting compression higher.
I figured out a long time ago, by trial and error, that a 318 doessn't suffer from low compression nearly as much as it suffers from loss of flow due to the ridiculous constraints of the heads they were designed with.

Mark.
 
Personally I like the 302 casting heads with 1.88-1.60 valves or magnum heads on a 318. With bigger valves you will lose your port velocity. A 318 will make more power than a lot of people think, and you can do it fairly inexpensively. I built one for a 73 Dart that I had and it ran very strong. The key is definately flow, that goes for any motor. I have found out that just hogging out a port on 318 heads will actually lose power, compared with stock ports. So you need to know a little about what you are doing.
 
Best 318 I ever built I just used HP 273 heads did not port at all. I have a set of 302 heads, are there templets on porting them?
 
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