318 Stroker

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65 Dartman

65 Dartman

1 of None 65 Dart Sedan Delivery
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Have done a search but not finding anything - maybe wrong search terms? Anyway, is there a chart somewhere that gives common combination of bore/stroke to yield final displacement for the 318?
 
384 @ standard bore
390 @ .030 over bore
396 @ .060 over bore
(if it can take a .060 over bore!)
 
problem you may have is piston selection for a 318 bore. Not many choices for 3.91 or 3.94 bore. 4.00 stroke is definitely available, not sure if anything else is without moving compression distance on piston or shorter rod for a longer stroke.
 
Oh! So sorry, you said common so I must have inserted the 4.0 crank.

So, yes, this is with a 4 inch stroke crank.
 
heh-heh

I think your other stroke choices are; 3.58,3.79,4.25.
The CIDs work out to 349,370,and 415.
Pistons may be custom.
Ditch the teener block. None of these displacements will work well with the teener top, so why hang on to the 3.91 holes.
4-inch kits are pre-engineered for the 360,(and also for 340s). Just drop it in and drive.Why re-invent the wheel?
Just asking.......................

Hey did you know that a 273-.020 over (3.65 bore),and a 3.79 crank will get you a tic over 317 cubes? So what you say?
Me too, heh-heh.
 
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The 318/4 inch stroke combo is fine. Better when bored bigger. The closer to a 4 inch bore the better. The bigger the bore, the better it becomes.

Being that the 318 is limited in ultimate bore size, under 4 inches, piston price does go up. A lot. It is a bit unattractive. But there are those who have done it and reported good returns.

The pro to this all is that you all ready have the 318 block instead of going out and spending on a 340/360 block and starting from there, scratch.

This helps off set the total cost. The big cost difference is the pistons. Do some home work on piston cost and figure out of it is worth it to you to get a 360 block (probably a cost of $100.)

Then go back to the C.I.D. calculator and see the different sizes. A .030 318/360/340 is 3.97/4.03/4.07.
 
Icon KB pistons for a 318 with a 4 inch stroke are 626.00 for a set...flat tops or dish...

icon kb pistons for a 360 with a 4 inch stroke are 626.00 for a set...

Summit shows another brand DSS Racing for 550.00...for an 408
 
If money would have allowed, I would have stroked my 318.....
390 inches and some head work and I'd keep up with most!

Jeff
 
I have done the 318 stroked to 390. I did it several years ago and it went in my '70 Challenger. It was a pretty impressive engine.
 
For me, if there is a next time, instead of building an HO 360 or a stroker, I'm just gonna turbo a plane-jane whatever SBM.I mean if it blows up, the replacement is a couple of hundred. What can you buy for $200. Shoot I could buy 2 or 3 spares, for next to nothing. Oh wait I already have 2 or 3 spares.
 
65 Dartman said:
Have done a search but not finding anything - maybe wrong search terms? Anyway, is there a chart somewhere that gives common combination of bore/stroke to yield final displacement for the 318?
Click to expand...

3.910" bore x 3.31" stroke
 
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AJ/FormS said:
heh-heh

I think your other stroke choices are; 3.58,3.79,4.25.
The CIDs work out to 349,370,and 415.
Pistons may be custom.
Ditch the teener block. None of these displacements will work well with the teener top, so why hang on to the 3.91 holes.
4-inch kits are pre-engineered for the 360,(and also for 340s). Just drop it in and drive.Why re-invent the wheel?
Just asking.......................
Click to expand...

My question was purely rhetorical, but since I have a teener that would need to be overbored . . . . . I was just wondering. I agree a
360 block would be best but are non-existent in my neck of the woods. I found out after the fact that a friend of mine took a workable 360 block (as well as a couple of 400s and 1 440 to the scrapper - he needed basically gas money!
 
65 Dartman said:
Have done a search but not finding anything - maybe wrong search terms? Anyway, is there a chart somewhere that gives common combination of bore/stroke to yield final displacement for the 318?
Click to expand...

Not sure about a chart however its like this with the std bores on stock stuff.

3.910" bore x 3.31" stroke = 318
4.000" bore x 3.31" stroke = 340
4.000" bore x 3.58" stroke = 360

Being as an intake will fit from 273 up to 360 inch engines its doubtful there is a deck height difference on the LA engines like you have between B and RB big blocks. All small blocks from the factory as far as i can tell use the same length connecting rods. The difference being the crank throw.

Theoretically put a 360 crank in a 318 to stroke it. Notice i said "theoretically" as a 360 crank will not physically fit a 318 or 340. Only because a 318/340 uses larger main journals, and the 360 crank is cut way undersized to be of any use. Hughes , eagle, and others do however make cast and forged stroker cranks to bump up the displacement of the 318. Most 318s cannot take a 4.000 inch bore however making the 340 block pretty prized.

The smaller bores on the 318 make valve shrouding a problem if running 2.02" - 1.60" valves. The stock magnum heads with larger valves than the LA heads though smaller than 2.02 - 1.60 valves strike a good compromise on a stroker 318. Engine quest make nice castings of these that are drilled for either an LA intake or a magnum intake.

Another option if you can still find them is old closed chamber 273 heads, but you have to do a lot of porting and upsize the valves, but are an option if trying to run 5 bolt valve covers.
 
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additonal note...scat and eagle make 3.58 stroke to fit 318/340 mains...a drop in no cutting of crank needed...

problem is piston selection for the 3.58 stroke in a 3.94 bore..

hughes sells cranks...they don't make cranks..
 
I have been looking at stroker kits for the 318 on mancini racing.
 
Ok heres the "chart", for a teener plus .030

........bore..........stroke...........CID
.........3.94..........3.31............322.85
.........3.94..........3.58............349.18
.........3.94..........3.79............369.67
.........3.94..........4.00............390.15
.........3.94..........4.125...........402.34
 
70aarcuda said:
additonal note...scat and eagle make 3.58 stroke to fit 318/340 mains...a drop in no cutting of crank needed...

problem is piston selection for the 3.58 stroke in a 3.94 bore..

hughes sells cranks...they don't make cranks..
Click to expand...
I stand corrected
 
I get building a stock stroke 318 but when stroking it's worth digging up a 360 block, your giving up 18 cid and breathing ability which is already a problem when building a big inch small block.
 
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