Thread: blow it or stroke it?

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Ive got a 90 stock 318 rebuilt 30 over - trying to decide which would be best bang for buck to get it in my truck and running - eventually ending up with both - so im looking at the best method (between my two options) to get it on the road fastest and cheapest.

Do I keep current motor config and top it with a 6-71 single double pumper and have fun till i pop the pistons - then rebuild

or

Do I send it in to get stroked to 390 capable of truly handling a paddle pump and just naturally aspirate it for now until the cash comes around to top it with a blower?

Any thoughts - thanks!

Man, go stroker. You'll need custom pistons, but you already have a pair of the best cylinder heads Ma ever put on an LA engine. Poke the intakes out to 2.02" and you're golden. If you're feeling silly, port 'em.

The small 318 (3.91") bore and the long 4" stroke means the flame will finish its sideways journey across the bore quicker, and have longer to push down on the crank... it would be a torque/midrange beast while maintaining reasonable power through probably 6.5-7 grand with appropriate intake/exhaust/camshaft.

I've actually always wanted to build one, but my current 318 project is followed by a 416" 340, then another 340 (stock stroke), then the 360, then the 474" 400... and I still have that '72 steel-crank 440HP to get after, too.

So many engine projects, so few cars...

One thing, though... if you plan to go blower later, you need to plan for it now, and that likely means miserable compression until you can get your "artificial airflow" installed.

Me? I'd stroke it, and when I got bored, I gas it.

Oh, and remember: .040" is maximum overbore for any LA-series engine (273, '67-up 318, 340, 360). Anything past that, and the cylinder walls will flex, costing you ring seal and power... assuming it doesn't let go entirely.

Im right there with you on the reasons to stroke it - though with the current stock rebuild I already have horrible compression (just north of 7.5) which is why i thought paddle pumping it now would be the cheapest way to go (im guessing about 3k with carbs and blower drive kit) where as Im at least 5k to stroke it naturally aspirated with a good single or dual plane.

so im leaning towards playing with current set up blown until I can save up enought to build the stroker around the blower req's

but whole reason for posting was to get others opinions cuz im not sold either way yet - but to me living with mild compression now makes the least sense without a blower topping it off.

Doc, thanks for the opinion - if you got more im listening.

stroked is nice, but I'd rather be blown.

Originally Posted by lt1s10

stroked is nice, but I'd rather be blown.

it is nice if you can have both

funny s*&% guys - no really - blown and stroked - why didnt i think of that - i could be a dick but ahh f*%& it - its friday and it appears none of us are getting either - but back to the real question - do you guys have any real pro or con to do the one over the other first? Id love to do both at the same time, but id rather have my ride peddlin faster then Fred flintstone in near future

watch you mouth but hey it mite be to late now i think you are out of here and yes why not both?a nd you may want to edit you post ?

Originally Posted by pat mccarthy

it is nice if you can have both

to much for me.

sorry - dont think about that stuff much - a mccarthy tellin an ocallaghan to settle down - thats funny - thanks guys - later

Originally Posted by blackmopar04

sorry - dont think about that stuff much - a mccarthy tellin an ocallaghan to settle down - thats funny - thanks guys - later

hey no big deal they tell me that this is a family formum i did not thing i would last this long but try to keep it a family thing

Originally Posted by blackmopar04

Im right there with you on the reasons to stroke it - though with the current stock rebuild I already have horrible compression (just north of 7.5) which is why i thought paddle pumping it now would be the cheapest way to go (im guessing about 3k with carbs and blower drive kit) where as Im at least 5k to stroke it naturally aspirated with a good single or dual plane...

Doc, thanks for the opinion - if you got more im listening.

Well, right off the bat: you realize you'd be way ahead of the game with a 360, right? Cubes is cubes, and more is better. Hence building my stroker on a 340 block, which has a larger bore than even the 360.

I would hesitate to hang a blower onto a cast-piston engine with an iron crank, though at your low boost level you'd likely be OK. Mopars have stout bottom ends, as evidenced by my repeated 7000-plus RPM shifting of a stone-stock iron-crank 340 with over 130K on it. Th Mopar's long rods (all factory SB Mopar rod are only .012" shorter than a big-block Chevy rod, and almost an eigth inch longer than the "good" 6-inch SB Chev rods) mean great rod/stroke ratios and low rod angularity, so side loading of the piston is less than in your average SB Chev, which, when combined with the high-nickel alloy used in all Mopar blocks, is why you see 150K-mile 318s with almost no ring ridge. My only real concern with the huffer would be detonation; I'd suggest a MSD 6AL-BTM box to combat knock.

My #1 reason to prefer the stroker, really, is the sleeper factor. It doesn't matter what you tell the guy when you open the hood, a blower is a blower. If you're at a show, cool. If you're on the street or at grudge night, well, I'd just as soon have the sleeper effect of a 390-inch engine with "318" cast into the side. Strokers never break belts, they aren't a pain to tune (you do realize that either option means sayonara to your current EFI setup, right?), they don't whistle, and strokers don't cost you bottom-end power via parasitic drag; in fact, they increase it due to sheer airflow. Also, the long-arm shortblock will more easily be adapted to future upgrades like ported heads or a bigger cam than supercharging.

Quality stroker kits for small-blocks can be had for well under the cost of the blower and its attendant parts, too... any Mopar mag will have ads from several places with kits under $3000; since the pistons are often custom anyhow having a 318 piston made shouldn't increase the price much, if any. In the long run, I think the stroker would be more cost-effective and less of a pain in the arse.

Start with the right shortblock first, then expand from there.

Besides, you can always add a supercharger to the stroker later...