If anybody can relate to that, here I am.
Thoughts on a 390 cu in. stroker from a 318?
- Thread starter volaredon
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I agree if you are comparing a stock type rebuild to a forged steel, aftermark rods and forged piston type stroker build. But if stock type parts are good enough then a cast steel stroker crank with stock rods and cast pistons might be an option. If the stock crank needs to be reground then that would have to be accounted for also. Still the stroker will be more expensive but at less cost per torque gained. I would do a full accounting of each combination and compare the cost of each to the likely torque output of each combination.
To the op: If over the years in your experience the stock 318's have proven to give you the best service then why not stick with the 318 and build a stock stroke 318? I'm sure it will get you where you want to go and it might warm your heart alittle knowing you got there courtesy of a 318.
I'm with Tom on this one. If you're limiting yourself to nearly stock Magnum heads, a 5.9 Magnum with stock stroke makes a lot more sense. Stock heads on a stroker is like putting 318 heads on a 360. Great up to about 4500 but completely out of wind after that. Work the heads with a proper valve job with a little bowl work and some springs and retainers for more lift. Use the money for some icon pistons and good head gaskets to get you to 10:1 with some quench and a proper cam regrind. A proper distributor curve with good ignition and tuning will be what makes it. Just my .02, FWIW...
340sFastback
Well-Known Member
I think a 4 inch crank in a 318 block is going to be able to get that truck moving a lot easier then a 3.58 inch stroke 360 would.
Like others said the larger bore and increased displacement of a 340 or 360 doesn't really matter much on the milder builds.
Like others said the larger bore and increased displacement of a 340 or 360 doesn't really matter much on the milder builds.
This is a 408 I dynoed for a high school kid. It was the first motor he overhauled and he did it by himself. Ebay or summit (don't remember) crank and pistons, stock rods, Summit cam #1789 272/.454, whistled @ 8.4:1, stock LA heads, edelbrock performer, 600 quick fuel with 1" spacer and dyno 15/8" headers. Had to fix some oil leaks but it made it through the dyno session. Motor was for a pickup.
That's exactly what this truck started out with. That engine is still running, 1/4 of a million miles on the untouched bottom end in my son's 72 fury wagon. Especially after I put the EQ mag heads and a 4 bbl plus a stock replacement 360-2bbl cam it was (and still is) a different animal than it started out. But since that engine is in a different body now I gotta build something and since I now have a 28' jayco camper that I didn't have when that truck was mine the first time I figured I'd try for the "Tim Taylor" effect and build something (hopefully mostly out of what I have here collecting dust) that would be more powerful... Swapping from the 727 to the NV4500 by itself will be an improvement I think anyway...
I'd be leaning on the side of just going with your original plan, 360, were talking mainly 1,500-3,000 needed power to tow cruises etc.. A decent 360 can make around 400 lbs-ft at 3,000 rpms which is 228 hp, not too sure what it does at 1,500 rpms but let's say 350 lbs-ft which is a 100 hp, if the 390 & 408 made similar torque to Cid at those rpms, they would make 107 & 113 hp at 1,500 rpms (not much of a gain) and 247 & 258 hp at 3,000 rpms a 19-30 hp gain but only at full throttle, I'm sure the little extra would help but is it worth the money, that's up to you.
If you truly want to know "if it is worth it" or how much "save some money" is you need to put pen to paper and do some accounting. Many times the phrase that you hear at uttered at the end of an engine build is " If I would have known it was going to cost that much money, I would have...".
Honestly, this is one of those build descriptions that make me wish it were possible to drop a distributor in a Gen3 Hemi… if it weren’t for all the mega dollar support hardware to make it work, I would have tried playing that game a long time ago…
Not too impressive but it was a pretty mild build.
What does it take to make THAT happen with a carburetor? A crank trigger?
I thought the torque curve was good!
DionR
Well-Known Member
Assuming by "mega dollar support hardware" you mean electronics, I plan to run mine on about $300 of electronics. Plus $475 for a MPVi3 and credits, but those don't have to be bought. And that includes $70 or so in a harness and TIPM to try and make that work and isn't at all needed. So for less than $250 in electronics, I should have a stock motor up and running. Too bad I'm not running a stock motor.
Not to say it is a cheap swap. I am $4500 into my swap so far and while I have a motor and fresh heads and such, I still need to re-ring it at least. But it does include my fuel tank and pump and all the swap parts. Still need fuel line/fittings and cooling.
Don't ask how much I have into it all if I include my T56 and the purchase price of the car.
wow, i'd hate to build anything for you.
It is pretty mild. I think the takeaway from this build is the torque curve. Look at how low the rpm is at which it starts making 400 and how long it hangs on to 400 in the rpm range. Imagine you are pulling a 28' camper as the op is planning on doing. I think for a mild build it has the power right where you would want it.
Oh I agree. Sorry I kinda got off on a tangent.
I thought it was very impressive. Especially for a kid's first build. Even if it weren't, it's still a really strong combo. I'd be stout in a truck or A body. It's easy to get hung up on numbers. People sometimes forget what 400 foot pounds can do.
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