I'd do a mild big block.

1) I really wish this myth of all magnum heads cracking would go away. Its right up there with the factory overdrive slowing the vehicle down 1.5 seconds. rubbish. Some heads crack, no more than 906 heads cracking between exhaust ports. Millions of magnum motors are still on the road (my own truck has 161k and gets worked like a dog) none have ever ended up in my work bay because there was an issue with heads and I was a Dodge line tech.

2) There is several carb intakes available for the magnum heads, they are not hard to find. Mopar, Edelbrock and even the Chinese make a knockoff called crosswind with dual bolt pattern.

3) If you really are worried about heads you can buy the Aussie Enginequest magnum heads setup with valves and springs up to a 600 lift cam for under a grand, with or without LA bolt pattern. You can also get a cast iron Indy head for a little more money.

I have contemplated the same question with my '67 Dart shown in my signature line. The car is to be a fun street car with good brakes and decent handling.

The initial plan was to install a very healthy iron headed Magnum based engine between the rails.. but then I picked up a 400 motor.. and then a killer deal on Schumacher B/RB headers...

Weight wise it would pretty much be a wash between the iron head magnum engine and a 400 with aluminum heads and the Duster the headers came from ran mid-11's with a 440..

What to do?

I have a set of em & they do look nice. Best guy to deal with on them is eric Haugland the EQ importer in las Vegas. yes get the LA pattern

360. I can build a stock stroke 360 that will put an A-body into the 11's easily. I've built a few, all the same build. 360std bore, KB 10to1's on stock 273 rods. I don't change balance at all. windage tray, stock pan. stock heads with fresh valve job, 508 purple shaft with roller tip adjustable rockers set lash at zero. Single plane torquer II intake, 750 DP holley with some bigger jets, squirters. Hooker headers. factory electronic dist with recurve springs. That's all I do. The first one I built ran in a full body, interior, exhaust, stock suspension 68 dart. Also had a stock convertor in a fresh 727 with shift kit and 3.91's. Very simple, cheap build that ran like crazy. It went 12.40's with zero traction over half track at over 115mph at the finish. If I had the chance to change the convertor, put the 4.30's in it and some sticky tires it would run mid 11's easy. Had over 435 at the wheels. You don't need strokers and big dollar fancy parts to go fast if the combo is made for each other. Want to see the car do a burnout? Go to youtube and lookup Kenworthgoose. WE were in Heath at the Chrysler dealer that year.

If I was starting from scratch, hands down a junkyard magnum 5.2/5.9 with a supercharger or turbocharger. 500+hp for pennies on the dollar compared to a comparable n/a SB or BB.

I got a set from Hughes Engines, been on the car since 2008. I wanted the LA pattern intake since I was running a factory a/c setup and wanted to look stock under the hood.

My preference for thirty years has been 440s and have done 440 A body swaps, but looking ahead I would do a gen III hemi. Drivability, performance upgrade availability, cool factor, resale etc. etc.

That would be my choice, too. The only advantage the big block has is that the dist is in the front and extra stock cubes. Spark plug access, header design, weight bias are all in favor of the small block. A much better balance.

Semi daily driver huh?? I think I would just keep it simple and go with a 360 build, then put money into a nice suspention, shocks, seats, and reliability items like a good radiator, firm feel steering box etc.. This way you will actually enjoy driving it in all conditions other than just straight line.

BBs don't belong in 12 second a bodys, not really even worth the hassle till maybe mid 9s. Simple jobs like spark plugs are not simple, you stuck with a 727 if you want an auto and they are heavy.

The Gen III hemi is awesome but sooooo expensive to get it in (motor mounts, headers, oil pan, EFI or carbs are both expensive and painfull when you count "good" intakes that will eat most of $1000, all the accessories evn from the JY are still expensive, aftemarket flex plate) if you buy a drop out with the harness and computer it is expensive and eats all the $4500 when you throw in mounts, pan, headers... and you might get 400 hp without breaking it open. It is the lightest option witch is good and you should get in the 12s.

A 408 is the easiest, cheapest most fun combo. Get a set of EQ heads from hughes under $1000 ready to run. Get a SCAT rotating assy with I beams and it drops in with no grinding needed. Get the roller reground at delta cams for under $100 the one I use most is 221@.050 110 LSA and pulls like crazy and will runs 12s easily in an a-body. Motor mounts, oil pans, headers... are a dime a dozen, plugs are easy to swap, you can run a 904 for more weight savings and eliminate the traction issues a front heavy BB has. If you can not run 12s with this and keep it under $4500 you are paying someone too much.

Now if you ever might want to step up the power a whole big bunch than the new hemi is hard to beat. Don't want a stock flex plate with a big power SB so thats now a wash, Cheap headers won't run really fast in a SB so they are a wash, don't want cheap oil pans running real fast so they become a wash, a set of eagle heads flow 330ish cfm and cost around $1000 or less used usually then you get rockers to boot, a 330 CFM SB heads gonna run $3000 with rocker... you can still run the 904 and save the power robbing 727 for your BB budies.

No offense but you should be able to run 12's with nothing more than a 5.9 with a good cam, intake and headers with a set of 3.91's or 4.10's out back.

I'm running 13.0 with a 5.9 and 3.55's in the worlds fattest'74 Duster at 3675 lbs with driver while bucking a headwind at Lebanon Valley.

Almost imposible to find a non cracked magnum head. I have torn apart 100 cores to get 2 litterally. Most of the time I just look the other way as they don't cause issues, I just needed a pair to install bigger valves do a bunch of porting and felt I should start with a set that is not cracked. I have had the best luck with the early casting, never seen a later casting that was not cracked. If this web site did not get all screwed up a while a back I would post a pic of how to identify them still in the car. Even so it is 1 out of 5 of the early ones that had no cracks, most of the ones on my shelf evn the early ones have at least one crack, the later ones have both ends cracked most of the time. The crack many times more percentage wise than 906 heads, they just don't seem to ever cause an issue. A bigger issue I see as these engines age is the receding exhaust seat, try getting a machine shop to install new seats when there is cracks also.

Whoop...

Dere it is...

Have you priced out rebuilding and porting stock iron heads , nevermind choosing the worst design possible ... an OPEN CHAMBER stock iron head ... it would be cheaper to buy a set of E brock heads than to redo iron heads.


Build a smallblock stroker or do a 5.7 hemi build ... headers in a big block A body are not a joy , figure a Hyd clutch so it's easier to deal with for header clearance , especially big block .

I think you misunderstood me.

I meant ported 452s as in three-angle valve job at the most... hence just cleaned up.

Sorry for the confusion.

What I did was put in a 400 B engine with Edelbrock heads, a mild cam and a tunnel ram. What I would do with a fresh slate today would be a Magnum based SB with aluminum heads and a 4" crank- with compression to allow for a Vortec blower down the line. The 5.7 hemi is a great motor, but not enough bang to the buck from what I've seen.

I think an A would be much better balanced with a SB. I'd build the 5.9 or 408 as light as you can afford, preferably with Ed heads, and then focus on the rest of the car. Or a gen III but they are expensive and tight fitting.

Takeout 6.1 Hemi all day!

Light weight, makes great power and will pull down 20 mpg with the right gear.

Keep in mind that I own (and love) 2 340 stroker A-body cars, but if I were wanting an (easy) 12 second car on the cheap (read - starting with a bare shell and no parts on the shelf yet), I'd go big block, and I'd choose the 400 for the extra room they offer. And for the cornering crowd, a 400 with aluminum heads and accessories isn't going to outweigh a small block by much if anything.

Don't need alum heads to make a big block A-body handle...but I know you already knew that...This beast even had iron exhaust manifolds.