Small block stroker

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It sure has, and not for the better! I think that just the pistons without rings are $125 from summit now. What year 318 block do you have? It’s best to just get the decks cut just enough to true them up. Sometimes you get a block taller than factory spec and a 360 crank that cleans up to less than 3.58 stroke (spec is actually 3.578 according to some piston manufacturers) the pistons don’t come out of the hole as far, which will let you get by with a slightly thinner head gasket. The .086 cometic (it’s the one I found in stock that affords the minimum recommended .045 piston to head clearance) gives a 9.9:1 compression ratio, accounting for 1/2 cc/valve relief.
If you have the typical too tall deck 318 and are between.015-.020 out of the hole, this head gasket would give a little over 10:1.
Cometic Gaskets 4.080 MLS Head Gasket .060 - SBM : C5622-060
But I’d run the thicker gasket either way and spray it with the 9.5-10:1 compression and judicious tuning techniques, if I could obtain steel rings. The last set of total seal standard type steel rings for a .030 318 Stroker I seen cost about $300 to obtain, so that could be a dealbreaker on the nitrous.
Like I said, if you need a 360 crank, I got a 1988 casting with a good balancer that needs turned that you could have for the cost of shipping. Same goes for the standard bore roller cam 318 block, I just have to get the rotating assembly out of it.
 
It's a 1975 block from a dodge truck, I've got other 340s that need to be built and I have two 360 magnum cores just working my way through them, your a book of knowledge thank you for all the information!! My 421 I had professionally built so I wasn't a part of the build most of my other engines are self built but purpose built this conglomeration is going to be a bunch of random parts and hope for the best I would certainly prefer to keep it under 10.5-1 I have access to jet fuel and VP race gas but would much rather run it on 91 if i can
 
If you allready have a good 360 core, it makes zero sense to do a bunch of crank turning and custom machine work to put a 360 crank in your 318 block. All you would end up with is a engine that's smaller than the 360, with thinner cylinders, smaller main caps, and twice the effort.
 
If he can get the oil to the rockers on the speed master heads, that would definitely be the way to run here. A set of KB flat top or small dome pistons puts the compression wheee you want it, and a valve spring swap lets you run a hydraulic roller cam. All for probably less than any 318 stroker variant.
 
The aluminum Speedmaster heads oil just like any other LA head thru the shafts...

if you are putting them on a magnum block you can oil the shafts with PRW stainless steel rockers with the correct lifters and pushrods
 
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Im not dead set on stroking it , just looking for conversation and brainstorming ideas if anything just looking for a stroker kit.
 
I'm building a 318/392 stroker. ...the overbore is .040"

What CID does a .060" over 318 stroker work out to????

Jeff
 
What years are your 360 magnums? And what kind of rockers do you have for the LA heads? The earlier magnum blocks have the bosses carried over from the LA and can be drilled for rocker shaft oiling. Some builders have plumbed in hardline instead of drilling the whole length, but drilling and tapping the main galley between the lifters is tricky. Oregon Cam Grinders can take one of your stock roller cam cores or an engine tech eBay hydraulic roller cam (had a friend do an enginetech and Ken was able to get a 108 LSA on it, .506 lift 260/268 degree for a magnum) and put a custom profile on it for you.
 
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