“Max effort daily driver” 318 build vs “Budget” 400 swap

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Charlie_es_cool said:
funny that you mention
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Well isn't that a hoot;
My cam talk is/was based on an advertised taken at .008Tappet-rise. Whereas the Comp is taken at .006, making it measure advertised bigger than a .008 cam.
In other words, the 218/[email protected] that I recommended, when converted to .006 could easily be a 218/268 @.006,
therefore;
you and I are on the very same page; Nice engineering Charlie.
FYI
Just so you know;
With alloy heads at .028Q, and a Dcr up to 9.2@ about 195 psi,, I have always run my 367 on 87E10; with full-timing and absolutely no sign of detonation. My all-in timing has been delayed to ~3400rpm, just cuz I ain't taking no chances, and my butt-dyno cannot tell the difference anyway!
Your 318 combo is looking good.
 
rumblefish360 said:
What did it come out of?
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Charger, if you look close it has the same flange as a 360 2bb.

100_2398.JPG
 
sireland67 said:
I know the early ones are better, I am thinking the cast date on this one is 1973, I cannot remember.
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My buddy seen the pistons when I pulled the heads off n said "THOSE THINGS LOOK LIKE THE TOPS OF HAWAIIAN PUNCH CANS" lol
 
chilsam said:
My buddy seen the pistons when I pulled the heads off n said "THOSE THINGS LOOK LIKE THE TOPS OF HAWAIIAN PUNCH CANS" lol
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I just picked this one up to make stroker engine out of.
 
sireland67 said:
I know the early ones are better, I am thinking the cast date on this one is 1973, I cannot remember.
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Not exactly. The early ones are better in one aspect, the later ones in another. It's really splittin hairs.
 
RustyRatRod said:
Not exactly. The early ones are better in one aspect, the later ones in another. It's really splittin hairs.
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Thats news to me..how are the later ones better ? I know the early 400B's have thicker main saddle n web castings ??? 440 source says the later 440RB's are better...I'm just going off the info they have tho.. :elmer:for info
 
Charlie_es_cool said:
Funny that you mention a 218 @ 0.050 cam for the 318, since the camshaft I'd use If I were to build the small block would be a comp cams 268H.......

I actually started out by picking the 3.21 gears. My car has 26 inch tall tires. Cruise RPMS at 65mph calc out to 2700, and 2300 at 55mph. Going to 3.55 gears would have put my my 65mph rpms at 3000. I know some guys have no problems cruising at 3k rpms, but I would rather cruise below that. Like you said, settling for 3.21 gears puts a limit in my camshaft selection. Although I would still choose the same cam even if I had an overdrive trans and 4.10 gears.

Next thing I did was calc out the compression ratio. Using KB flat tops 0.012" down the hole, 0.028" thick gaskets and eddy heads with 63cc chambers calcs out to 9.5. Milling the heads to 60cc brings it up to 9.9. With a compression ratio in this range, I picked out he comp 268H for 2 reasons. First, in this thread they dynoed a 9.1:1 318 with eddy heads and 252h camshaft. A build like that is my idea of a "max effort daily driver". Cranking pressure on that engine was measured at 170psi, and dynamic compression calcs out at 7.88:1 using the wallace calculator. I would have no problem using a camshaft that size, since it worked so good in that build. But using that camshaft on a 9.5:1 engine results in a 8.22:1 dcr. I feel that's a bit too high. The 268 with the same static compression ratio spits out a 7.81:1 dynamic comp ratio. Second reason I chose this cam is because I expect it to work with my factory converter. Someone with way more experience can chime in on this, but I understand this cam will come on somewhere between 1500 and 2000 rpms. And regarding David Vizard's 128 rule, a 110 LSA is what it calls for in this application (318 with 2.02 valves and between 9.5-10.5 comp).
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iam running that combo now
68 340 thin head gasket 268 H 218@50 454 lift 110/106 manifolds free flowing exhaust elec ign stealth 650 dp tuned carb power timed 727 tf2 3.23s now 3.91s 235 60 14s
169 cranking psi
10-1 comp
8.21 dyn comp
vp index 138
its a great street cam smallest ive used lots of low end pulls hard to 5700 5800
100k plus bottom end virgin from 1968 fresh top end
with 3.91s id use the 270 H or the xe268 221 228 cam
with the 3.23s dead stop punch tach goes to 5700 spins 45 50 feet 10 feet in 2nd
with 3.91s right to 5700 45 feet shift to second tach stays @5700 for another 45 50 feet if i so choose
edit
your combo 3.21 gears id use comp cam ex256h 212/218 447/454 110
would be about equal to my 340 218@50 3.23s
 
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chilsam said:
Thats news to me..how are the later ones better ? I know the early 400B's have thicker main saddle n web castings ??? 440 source says the later 440RB's are better...I'm just going off the info they have tho.. :elmer:for info
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The later ones are more consistent with less core shift. The iron is more evenly dispersed. All the later engines are similar in that aspect, because the casting process kept getting better and better.
 
Another thing to consider headers or manifolds, neither are cheap for a BB swap. My vote is a nice 360 because you already have manifolds, headers and other sb parts. Keep the 318 for a spare. Sell the 400. Remember you said daily driver.
 
Carnut68 said:
Remember you said daily driver.
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Why isn't a big block good daily driver?
Whatever power level eg.. 300 350 400 hp etc.. 400 will be the mildest version needing less gear stall, it will make the most power idle-4500 rpm where 99% of street driving is. The only so called drawback is size and weight which are minor compared to the benefits. A mild 400 would be an awesome daily driver, only thing better 500 plus.
 
273 said:
Why isn't a big block good daily driver?
Whatever power level eg.. 300 350 400 hp etc.. 400 will be the mildest version needing less gear stall, it will make the most power idle-4500 rpm where 99% of street driving is. The only so called drawback is size and weight which are minor compared to the benefits. A mild 400 would be an awesome daily driver, only thing better 500 plus.
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I agree
 
273 said:
Why isn't a big block good daily driver?
Whatever power level eg.. 300 350 400 hp etc.. 400 will be the mildest version needing less gear stall, it will make the most power idle-4500 rpm where 99% of street driving is. The only so called drawback is size and weight which are minor compared to the benefits. A mild 400 would be an awesome daily driver, only thing better 500 plus.
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Agreed and with a mild cam and reasonable head work it can make very good easy going lower and still get decent mileage. I was getting 17 mpg’s with 3.55’s on a 27 inch tire.

The weight issue disappears with aluminum parts. The smaller more inexpensive items are the water pump and its housing. A cast iron housing is very heavy on the BB engine. The water pump is small potatoes. But you might as well match what the small block came with. An aluminum water pump and timing chain cover. The timing cover on a BB is super light weight.

The aluminum intake is a nice weight saver and the expensive part is cylinder heads. Which MoPar Joe showed us there lighter than expected for sure.

The 727 is heavier by sheer size. Not a huge thing.

Pound for pound, the B (and RB) engine is a better deal.

On the 400 I have, I picked up a 440source.com aluminum water pump housing which has the inlet on the same side as the small block. That’s a FWIW. But here is the nice thing about that. The radiator used can be used with a small block later on if you want.

I used a Summit racing radiator, aluminum and big, price is right and cools well.
 
Nuthin at all wrong with a fat motor daily driver. Nuthin. The only "drawback" with the A body is exhaust. And that can be over come with mo money.
 
TTI has the best headers for this. Stock manifolds would do just fine if they’re the correct fitting ones. Fender well headers are just dang pricey.
 
rumblefish360 said:
TTI has the best headers for this. Stock manifolds would do just fine if they’re the correct fitting ones. Fender well headers are just dang pricey.
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I agree 100%. With only as mild of a big block as you really "need" for a street car, the HP manifolds would work fine. Too many people over think things. These cars are very light and even a blueprinted HP 383 would make an A body very quick on the street.
 
You'll get more performance per dollar with the big block. Small block parts are currently more expensive than Big block.
 
RustyRatRod said:
I agree 100%. With only as mild of a big block as you really "need" for a street car, the HP manifolds would work fine. Too many people over think things. These cars are very light and even a blueprinted HP 383 would make an A body very quick on the street.
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Most would be satisfied around 10 lbs per hp give or take a lb or two, with good power idle-5500 rpm, peak around 5000 rpm which would be about 0.9-1:1 hp:cid, easy obtainable goal, 360-400 hp with a mild 400, 285-320 for a 318, mild with the right head.
 
I've been in those shoes.
Put the 400 on a stand, don't get in a hurry, keep driveing the 318 and build the 400 with the best internals and heads you can find even if you have to save up more.
I had a 5.9 Magnum short block,a complete running 318/904 and a complete running RV 440/727 when I rebuilt my Duster back in 2018.
I ended up rebuilding the 318 just to get the car on the road the quickest because I only needed headers and motor mounts to get it in...(so I thought)
Power creep( the May as well's or while I'm in there) set in as usual.
I rpm matched the parts, went with the cam that all of my buddies say is too big to make low end (just to prove them wrong again)
I've had a 440 that has been on a stand for 2 years that I JUST dropped off at the machine shop last week. My Duster is a fun car to drive but if I were to do it over I would build the big block.
It cost me $15k to rebuild the whole car in 2018. With small block parts prices today it'd be around $28k to do the same again.
 
273 said:
Most would be satisfied around 10 lbs per hp give or take a lb or two, with good power idle-5500 rpm, peak around 5000 rpm which would be about 0.9-1:1 hp:cid, easy obtainable goal, 360-400 hp with a mild 400, 285-320 for a 318, mild with the right head.
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Just like a stock 383HP. Can you say 425 LB Ft? Even so, I still recommend warming up the 318 first. It will keep the car running and the chance for losing interest much, much lower. Then I would work on my 400 and basically build it in the same way I would a 383HP, compression and all. That would probably reach out and touch 500 LB FT.
 
RustyRatRod said:
Just like a stock 383HP. Can you say 425 LB Ft? Even so, I still recommend warming up the 318 first. It will keep the car running and the chance for losing interest much, much lower. Then I would work on my 400 and basically build it in the same way I would a 383HP, compression and all. That would probably reach out and touch 500 LB FT.
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solid idea on warming up a smallblock for the quick and easy enjoyment with a back burner build for future shenanigans. the best part about that is you can slowly amass the parts needed for the swap scooping up deals along the way.

i'm with you on a BB build. give it some compression, work the heads a little, go with a more conservative cam, top it with a dual plane and modest 4bbl. no snarly, tooth and nails beast. no drama. everything is done by 5500 and a boat load of torque that will roast the meats on command.
 
If the car is drivable right now, I wouldn't fart with the 318, I'd drive it and build a 451/470 stroker to replace it with.
Too many guys on here think small and cheap, I don't, never have.
 
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