318... to stroke or not to stroke???

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Well, I'm working on a budget, and I can waste money on a 360 block or use the 318 block I already have. I'm choosing to utilize that money for better go fast goodies, I Was presented with a great deal on the 402 pistons. I'm building a street bruiser..... just really want to have a badass car.....
 
sport74 said:
Well, I'm working on a budget, and I can waste money on a 360 block or use the 318 block I already have. I'm choosing to utilize that money for better go fast goodies, I Was presented with a great deal on the 402 pistons. I'm building a street bruiser..... just really want to have a badass car.....
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I get that
But by time you sonic check the 318 You could buy a 360 block
 
sport74 said:
Well, I'm working on a budget, and I can waste money on a 360 block or use the 318 block I already have. I'm choosing to utilize that money for better go fast goodies, I Was presented with a great deal on the 402 pistons. I'm building a street bruiser..... just really want to have a badass car.....
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I'm not trying to poo poo your decision here to save money, but the engine is only part of the deal-have you set aside any money for modifying the trans, buying a converter, gears, exhaust upgrades, chassis stiffening, etc?
 
I've got a 727 for it and a 8.75 sure trip with 3.94s plan on chassis stiffening as well. I've got a friend who's a machinist so that saves me some money too
 
Boring a block out +.090" is not advisable.
A lot of machine shops will straight-up tell you that they won't do it.

I've seen blocks at +.060" that after one season you could poke a screwdriver through the bore and the tear would look like tinfoil. no exaggeration..

You have a 318 block and crank but 360 stroker pistons, I don't like to be the bearer of bad news but it's probably going to be a problem and machining is probably not going to be a very cheap solution in the long run.
 
frosty_the_punk said:
Boring a block out +.090" is not advisable.
A lot of machine shops will straight-up tell you that they won't do it.

I've seen blocks at +.060" that after one season you could poke a screwdriver through the bore and the tear would look like tinfoil. no exaggeration..

You have a 318 block and crank but 360 stroker pistons, I don't like to be the bearer of bad news but it's probably going to be a problem and machining is probably not going to be a very cheap solution in the long run.
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318 blocks seem to be the exception to the rule. I've seen several posts and read articles where a lot of 318 blocks sonic check plenty thick to go .090 over. Just gotta sonic check them to make sure

As for the pistons, their 4" diameter pistons designed with a compression height to accommodate a 4" stroke crank in a 9.59" (Chrysler LA) block. Doesn't matter if you use them in a stock bore 360 block or a .090" over 318 block. The required dimensions are the same and the only difference in machining the 318 is you take out a little more metal due to the .090 over bore. All the machine shops around me charge a flat rate for boring an engine to whatever over bore you want.

The 402 stroker has become a pretty popular combo in the last couple yrs. since there are so many discarded 318 blocks that you can get for practically nothing.
 
OK so if I decide to go to the 360, will it matter if it's magen or la? The cam I have is for a la and has hydraulic flat tappet lifters, and before someone pips off with "send it back and get a different kind" I have bought heads that were custom set up for that cam/lifter combo
 
Sport74 I saw where you mentioned earlier about reusing your rods. I hope you don't plan on reusing old rods as-is cause they most likely need resized (they get out of round with age and wear) and to handle the power the stroker will make the bolts need to be upgraded. By the time you pay to get that done your knocking on the door of cost for a set of aftermarket rods that are stronger and lighter. And don't forget to ad in the cost of getting the rotating assembly balanced. That's a necessity.
 
sport74 said:
OK so if I decide to go to the 360, will it matter if it's magen or la? The cam I have is for a la and has hydraulic flat tappet lifters, and before someone pips off with "send it back and get a different kind" I have bought heads that were custom set up for that cam/lifter combo
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Since you have EQ heads (magnum style that oil the rockers through the pushrods) it doesn't matter. If you had LA style heads you'd have to use a LA block
 
fishy68 said:
318 blocks seem to be the exception to the rule. I've seen several posts and read articles where a lot of 318 blocks sonic check plenty thick to go .090 over. Just gotta sonic check them to make sure

As for the pistons, their 4" diameter pistons designed with a compression height to accommodate a 4" stroke crank in a 9.59" (Chrysler LA) block. Doesn't matter if you use them in a stock bore 360 block or a .090" over 318 block. The required dimensions are the same and the only difference in machining the 318 is you take out a little more metal due to the .090 over bore. All the machine shops around me charge a flat rate for boring an engine to whatever over bore you want.

The 402 stroker has become a pretty popular combo in the last couple yrs. since there are so many discarded 318 blocks that you can get for practically nothing.
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Indeed! It's done a lot!
 
...you can use a flat tappet cam in either an LA or magnum block. People are piping up to help you. You originally wanted to build a 318...you then said you can get a good deal on a stroker crank...now you're looking at the potential of running a 360 block. It's like a "choose your own adventure" book...every change you make will have different outcomes and requirements...318 stroker crank won't fit a 360 block due to main bearing diameter differences.
 
txstang84 said:
...you can use a flat tappet cam in either an LA or magnum block. People are piping up to help you. You originally wanted to build a 318...you then said you can get a good deal on a stroker crank...now you're looking at the potential of running a 360 block. It's like a "choose your own adventure" book...every change you make will have different outcomes and requirements...318 stroker crank won't fit a 360 block due to main bearing diameter differences.
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You're right! It seems as though I have opened a can of worms. I still plan to do the 318, and I have not yet purchased the crank, only the pistons. The pistons will work with either motor. Gonna check the block with the machinist before purchasing the crank. That way if I have to go 360, I haven't wasted that money and I was just wondering if the other parts I have will work if I go that route. Thanks everyone for the info it's all been really helpful!
 
Magnums rev faster, because they are lighter, have a roller cam, and not to mention serpentine belts!

The trade off is the stroker kits are more expensive.
 
Well after a heart to heart with my machinist and a few calls to salvage yards. ...... I caved in and went to the dark side! I bought a magnum 360 and now have a 318/ 904 combo to unload and some 318 30 over pistons and a few 360 parts to unload!
 
Anyone running a similar setup? What kind of plugs do you recommend and what about the coil is 58000v good or should I stick with a 45k?
 
I don't know what the big deal is about using 360 blocks instead of 318s for strokers. A good 390 isn't down on cubes that much, plus it has lighter pistons and crank with less inertia and rotating friction on the smaller main journals (318/340 vs 360). The only real disadvantage is possible shrouding of bigger intake valves (2.08" etc), but with 2.02 valves you would have had a nice little street engine. You don't have to go out .090", either - although it gives you greater piston choice (arguably the biggest advantage of the 360 block). Just ,my 2c.
 
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