Let's talk 318/349/390 strokers.

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Badart

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I want to build one on the cheap and turn my stock looking 65 Barracuda into a sleeper that can handle the twisties. I have all of the parts laying around. 68 318 short block, magnum short block, set of 1.88 J heads and a couple of 360 cranks. I am thinking about using the magnum block and go with a roller to help with idle issues.(Edit: I forgot that magnum block wont work with the LA heads Duh)

I have heard that you can turn down a 360 crank to 318 mains and make 390 cubes? What rods and pistons do you use? I would like to start collecting parts that I need and get it to the machine shop.

Post your combos.
 
If I remember right that makes a 349 stroker, and a 390 stroker is a 4.00" crank. I think I read somewhere that the magnum mains are the same so you can run a 360 magnum crank in a 318 magnum block. And yes people have turned down 360 mains for a 318 LA, that part is possible.

Someone with more info will chime in. :)
 
Also to note the 5.7 liter hemi is basically a 318 bore with 360 stroke... works well in that combo haha
 
I,ll be following this thread cause I have a 73 318 sitting collecting dust.The 318 2 bbl. in my 68 Barracuda can come out and get stashed away for a later date.I already have a 360LA crank turned .010.Can this be used in the 318?What about 360 rods and pistons?
 
I'm hoping to do a stroked 318 with our RHS heads before the end of the year. I'll probably build it with a solid FT cam and keep it just like the CC build but with a 950HP and our Bracket port job.
I expect about 510HP and 515TQ at the minimum.
Brian
 
If your going to use a Magnum block and LA heads, how do you plan to oil the rocker gear?
 
Dartboy52 said:
If I remember right that makes a 349 stroker, and a 390 stroker is a 4.00" crank. I think I read somewhere that the magnum mains are the same so you can run a 360 magnum crank in a 318 magnum block. And yes people have turned down 360 mains for a 318 LA, that part is possible.

Someone with more info will chime in. :)
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That sounds about right. There has not been that much info about these builds out there and I am interested.
 
ou812 said:
I'm hoping to do a stroked 318 with our RHS heads before the end of the year. I'll probably build it with a solid FT cam and keep it just like the CC build but with a 950HP and our Bracket port job.
I expect about 510HP and 515TQ at the minimum.
Brian
Click to expand...

Brian is that with a 4" crank or turned down 360 crank I believe it's 3.58" stroke?
 
Badart said:
LOL good point. You see I am just in the starting phase of this and you guys are good for something. I guess I will use the 68 block.
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Figured ya catch that .... ;)

I'd go with the 4 inch crank. Slugs will be cheaper and the torque output will be much greater.

The only time a see turning down a S/B crank was back in the day, a poor mans stroker we did was a 360 crank turned down for a 340 ... plus overbore, not a bad combo. 370+ cubes.

Slug price killed us though.
 
I did some research into the 349 stroker just for fun a couple years back. Very limited piston selection..
 
349 is gonna necessitate modified stock pistons or custom pistons.$$$

The 4'' crank is pretty cheap, but the 318 bore pistons arent.

Brian did a 318 block to 4'' bore and used the slightly cheaper std bore 360/4'' crank piston if I remember right, MadDart had it/has it.

I thought about the low low comp 318 pistons with a 360 crank,but.....
 
KB makes a reasonable price 318 piston for 4 inch stroke..
 
yea...id like to see a 318-372/390 stroker...i like LA style block and heads....dont care much for the magnum stuff...
 
I have run both.

A 318/349 build with the 360 crank turned down , factory ported 360 heads and a Comp 282S retro cam (.495 [email protected]), and

A 4" 318 / 392 with the same heads and an XS282S cam (.520/.540 - 245/252)

There is absolutely no comparison in the torque produced and the ease of build......go the 392.

349 issues as stated:

1 - Very limited off the shelf piston selection for a 1.65 Comp height slug. (Silvolite 1279 and there's a cast Badger available)

2 - Shaving down a flat top forged slug you run into P-V clearance issues.

3 - Money spent on turning down a 360 crank will buy you a cast 4" crank.

Best MPH with the 349 was 105mph.

Best MPH with the 390 is 112mph.

Carb/intake and gearing was the same (jetting was adjusted)
 
There's also two forged part numbers from Keith Black in the Icon series pretty reasonable for the 392.
 
StrokerScamp said:
There's also two forged part numbers from Keith Black in the Icon series pretty reasonable for the 392.
Click to expand...

He was talking 349 when listing those slugs.

On another note, there is another Icon piston available through Hughes for the 390. Somewhere between the other two, handy if you're juggling compression numbers.
 
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