Damn good info

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Princess Valiant said:
I've been toying with pulling the trigger on a magnum engine. I see them around but they seemed kinda foreign but now i think my dart is getting a magnum now that I know more of what is be getting into.

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Late comer to the thread….

The Magnum block is a better block. It’s just simply a newer block and it’s made a bit thicker. The problem with it can be the none oiling passages of the later years with use of the LA head as Tony describes. IF this is a hurdle to annoying, search for an earlier block that still has the oiling hole drilled.

The OE head can make power. Not a lot though. But how it comes in is another story and one you may like much. As cast and born, these engines make for excellent daily drivers with minor camshaft upgrades, 4bbl. intake and headers.

IF you keep the factory FI, the initial cost might be higher but the cost is worth it IMO since it is an excellent system. There are only a few intakes available for the Magnum head. The cheap chink knock offs are OK fine for a daily driver not looking for everything the engine can offer. If your looking to step up, the Edelbrock intake is it. After these two choices, it’s a single plane from MP or Indy. There quite the race style intakes.

Edelbrock (AFAIK) has the only aftermarket you DDD head for it. While it is a good street performing head that can be modified very nicely for a good strip showing, I don’t know if this is what your after.
 
MOPAROFFICIAL said:
It's no big deal, but its funny....to read people accept the magnum and over look the springs while they would never do that with the older LA motors. Nope... its ..."i would be changing the springs right away and sliding in that 256 or 262 cam and lead footing it off into the sunset..."
So I wanna know if these people are really tossing in a magum engine and just driving it with the stock cam and springs of which 'the stock springs are done and floating after 4500 rpm' while the stock cam is still there till about maybe 5200 rpm. 1st thing I did was change the springs and put some heads on. It pulls into 5500 range now.

My advice to all you guys buying one of these engines put it on the stand , change the oil pump , timing chain, remove heads and do the spring work whether changing the cam or not. It will turn more rpms qith more spring. The 986 comp double 1.437 is a good one to about .500 lift/55-6000rpm, after that get a better spring with more open. Those are only about 290's lbs open but have 130 seat lbs.
I would not put 500 into any stock casting magum head...so be sure they are good to begin with.. if not, get after market sm,eq,rhs,etc
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What spring would you / did you use on the stock head?
 
rumblefish360 said:
What spring would you / did you use on the stock head?
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I remove ALL the stock stuff, its usually tired/worn , heavy and weak.
If you want to know what I did with my heads...I threw 5.011 length 1.94/1.60 valves into them and cut for and use 1.437 diameter springs.
The height is raised .100 from 1.625 to 1.725, but in my case...a .065 hard washer under the rockers coupled with the gaskets 519SDiirr I used and .025 milled....gave the needed preload and stock push rods are retained. There are quite a few springs that seat at 1.70-1.75 installed @115-135lbs pressure and yeild 250-310 open. I have boxes of Springs and valves and things like that that are new and slightly used so I'm into making common things work, making his head except anything an La head could use ...basically. This is hot rodding...so I don't feel i need to stick with too many stock constaints. Like crap springs. With stock cam... I use comp 986 springs with 1.94/1.60,comp retainers,locks,shims to nail them to 130-135 seat about 255 open @.416 lift ..still room for up to .500..I also port them. I don't believe in putting heads on that dont flow well, Waste of effort.imo
 
Back to the Magnum engines. I now have several 5.9 running engines in various vechicals. A couple of weeks ago I bought another complete 2000 ram 1500 4x4 for $500. Have not decided to part it or drive it yet. I have bought trucks and Durango with the 5.9s for $100 to $1200. You can get the rusty rams with a bad transmission for $350 to $600 al day long and the one with a bad motor are even cheaper.

So far none of the magnum heads I have removed have been cracked. So is the cracked heads a problem with engines that have overheated more so than anything else?
 
Princess Valiant said:
I've been toying with pulling the trigger on a magnum engine. I see them around but they seemed kinda foreign but now i think my dart is getting a magnum now that I know more of what is be getting into.

Click to expand...

Magnums are the ****, 9 to 1 compression better heads bigger valves better stock camshafts 1.6 rocker ratio, roller camshaft, no exhaust manifold stud coolant leaks. We put a stock magnum 5.2 in my brothers plymouth just swapped on a intake carb and manifolds, hauls ***. Also delivers decent mileage.

687DC331-7426-45D4-865B-44C930C37C16.jpeg


D2119238-CDD0-4533-9856-84256F505CB5.jpeg


A1D94AF6-BC18-49C4-9F64-9730BE8F082F.jpeg
 
jos51700 said:
The magnum has much potential beyond and above the LA, namely roller cam, 1.6 ratio rockers, and the heads, although crack prone, are superior to any LA casting. Personally, I wonder if the cracking issue wasn't less of a thing than the internet made it out to be, namely because EQ or somebody would still be cranking those out if there was money to made there. I almost wonder if, for a many magnums are still out there, if the ones with terminal cracking have been filtered out. Disclaimer: I've not read up on why EQ got out of the game.

If I'm going V8, I'm going aluminum heads. If performance is what I'm after, do it right. If not, a bone stock slant 6 is fine.

All that said, I've vowed never to run another LA, but if I swap again, it'll probably just be to a gen III hemi, namely because they're still in production so the parts will be around longer than the magnums, but also if it's a power game, they win.
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I swapped used magnum heads off a 1999 block saw no cracks, ran a razor blade in between the cracks felt nothing, honestly the best and cheapest upgrade. Big butt dyno difference lol.

And honestly you just go to the junk yard all your losing is time and labor just pulling heads until you get that decent pair. it’s the name of the game hot rodding 101 sometimes you win some sometimes you lose some, but when you win you win!:thumbsup:
 
Jadaharabi said:
Back to the Magnum engines. I now have several 5.9 running engines in various vechicals. A couple of weeks ago I bought another complete 2000 ram 1500 4x4 for $500. Have not decided to part it or drive it yet. I have bought trucks and Durango with the 5.9s for $100 to $1200. You can get the rusty rams with a bad transmission for $350 to $600 al day long and the one with a bad motor are even cheaper.

So far none of the magnum heads I have removed have been cracked. So is the cracked heads a problem with engines that have overheated more so than anything else?
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What's it like on fantasy island? I can't find a pickup around here for less than $2k. If it's a D250, it's more like $8k
 
^^^^The sheet metal rusts away and leaves the drive train!!
I agree around here pickups are not cheap and they aren't rusted out either ! TEXAS!
 
I think the biggest advantage for a Magnum is when comparing a high mileage 5.9 to a high mileage 360. Almost any year 360 is going to be a low compression smog motor that has worn out rings and cylinder walls. The Magnum on the other hand has been run on EFI it's whole life and the cylinder walls will probably still show cross hatch and started with a much better compression ratio to boot. Put the same cam in both, figure out springs (they both will need them) and a decent 4bbl and the Magnum will almost certainly smoke the LA.

Rebuild/fresh one or both and it is a different ballgame. At that point it almost comes down to whether you want to run shaft rockers or not.
 
Jadaharabi said:
Back to the Magnum engines. I now have several 5.9 running engines in various vechicals. A couple of weeks ago I bought another complete 2000 ram 1500 4x4 for $500. Have not decided to part it or drive it yet. I have bought trucks and Durango with the 5.9s for $100 to $1200. You can get the rusty rams with a bad transmission for $350 to $600 al day long and the one with a bad motor are even cheaper.

So far none of the magnum heads I have removed have been cracked. So is the cracked heads a problem with engines that have overheated more so than anything else?
Click to expand...
The head cracking issue is overrated and blown out of proportion. I’ve been saying this for a long time. But everyone I meet, total strangers mostly, that see’s my 5.9 in my ‘79 start out by saying… “Your heads are cracked, what are you going to do about it?”

I just laugh and say “Not a damn thing! It runs fine and IF there cracked, I’m not worried about it.” I try an explain things and there one track mine takes over and it’s usually coupled with the I-d-10-T virus where there volume dial gets stuck and there ears close and they proceed to talk over me loudly coupled with statements of I have no idea what I’m talking about.


Ummmmm, yeaaaaaa, ummm, OK THEN!

The cracks are between the valves WHEN THEY OCCUR and there nominal is depth most times. If and when the crack appears, if it travels into the valve seat area, then you have a problem. And your engine still runs.

To answer the next question that pops up… no I would not out cracked heads on a engine. Yes, I get asked that and I can’t believe that I do but it happens.
 
Jadaharabi said:
Back to the Magnum engines. I now have several 5.9 running engines in various vechicals. A couple of weeks ago I bought another complete 2000 ram 1500 4x4 for $500. Have not decided to part it or drive it yet. I have bought trucks and Durango with the 5.9s for $100 to $1200. You can get the rusty rams with a bad transmission for $350 to $600 al day long and the one with a bad motor are even cheaper.

So far none of the magnum heads I have removed have been cracked. So is the cracked heads a problem with engines that have overheated more so than anything else?
Click to expand...
The plenum gasket leak has contributed. Imo Sucks oil, it cooks..glows, pre ignites.
Only real bad plenum leaks will get it rattling though, others just eat oil and gas and crust up the chambers.
The other thing about magnums... unlike La heads, mainly the 360 in my experience and not too many 3/18, which the in studs break when you try to remove the nuts... with a magnum the end studs are known to just break from the manifolds expanding and Contracting over many years. It's actually pretty common with foreign cars aluminum heads and cast iron manifolds as well. Once that happens ..it leaks and you can end up with a burnt valve, seat , and cracks can follow. My truck since in my possession has never been overheated. Don't have a any indicator it ever was. Doesnt mean it hasnt been. Cylinders still had cross hatch @299k. I'm really happy you had good luck with them Magnums Randall... I used to have really good luck with 360 heads...every one I ever found was good ....and then one day I pull a pair with confidence and find out they're cracked not at the seats but near the exhaust ports on the outside of the heads...then the next 3 sets were hit and miss, one would be cracked. Hope this last set I pulled yesterday are good!
 
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Slantsix64 said:
Magnums are the ****, 9 to 1 compression better heads bigger valves better stock camshafts 1.6 rocker ratio, roller camshaft, no exhaust manifold stud coolant leaks. We put a stock magnum 5.2 in my brothers plymouth just swapped on a intake carb and manifolds, hauls ***. Also delivers decent mileage.

View attachment 1715797040

View attachment 1715797041

View attachment 1715797042
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Nice..... real world review without right away getting into the racing stuff.

I like how you said butt dyno, because that's pretty much my method too.

The magnum was foreign to me, id see them at the pick a part and stayed away out of fear of the unknown. Now between the input here and the side to side visual provided by the video.....I'm wondering why I didn't look into this long time ago
 
So what year did the magnum start?

What year did roller rockers start?

I have a 90 360 in a D250, is that a magnum?
 
Princess Valiant said:
So what year did the magnum start?
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92/93-5.2-5.9 IIRC
What year did roller rockers start?
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They never came with roller rockers but the first appearance was in the late 30’s drawing table designed for air craft, but again, IIRC. AUtomotive wise, it was the 50’s on drag engines.
I have a 90 360 in a D250, is that a magnum?
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LA roller
 
Princess Valiant said:
So what year did the magnum start?

What year did roller rockers start?

I have a 90 360 in a D250, is that a magnum?
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Don't know if you watched at all, but I just went through the "prep" and install of a 360 magnum in place of an LA 318 in the past few short videos. Straight forward and not much to it.
P.S. - I know, I don't have a beard so I'm not much fun to watch ! :poke:
 
Princess Valiant said:
So what year did the magnum start?

What year did roller rockers start?

I have a 90 360 in a D250, is that a magnum?
Click to expand...
.
#1. The magnum was about 93 I think.
The LA roller motors stated about 88

#2 Do you mean roller cam motors? If so about 88

#3 A 90 would be an LA roller motor.

#4 Want to do some trading on that 90 D250?
 
Jadaharabi said:
.
#1. The magnum was about 93 I think.
The LA roller motors stated about 88

#2 Do you mean roller cam motors? If so about 88

#3 A 90 would be an LA roller motor.

#4 Want to do some trading on that 90 D250?
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  • 1992 was the 1st year for the 5.2 mag, 1993 for the 5.9 mag
  • 1985 LA's had roller motors for sure, as I've owned 2 of them. Not sure if any before '85
 
I don't know why anyone would swap a 'good running' 318 La for a 318 Magnum all that work for 20 horsepower perhaps seems really stupid.
Obviously if the LA 318 is smoked it's worth it. Aside from that exception.. I'd go with with more cid if I were pulling motors just for a power upgrade.

I get it, some of you want a cheery upbeat review. Okay ... they're great... they're great truck motors. After that strip them down to a short block and bolt good **** onto them and they'll really fry tires.

Hypereutectic Pistons, roller cam ,1.6 rockers, heads are okay if they're not cracked. Just change the basic **** ,oil pump, timing chain, cam if you want to really hot rod. Why is this a mystery. Lol
It's really common sense, it's just another 360 v8 with a better cam and bigger valves. As I've said in the past, if that same head came 1.88/1.60 instead of 1.92/1.625 it probably wouldn't flow the marginal amount more it does. Lmao it's a truck head for a 360. small volume,velocity.. torque. It's an example of why under 4000 rpm a ported 318 stock valve head will run better than a 360 head flowing the same. Sometimes it feels like this place take a few steps backwards catering to obvious hype driven nonsense. What yr is it?lol no offense to anyone.. just seems like geeking out with phonie Tony fever is going around. Maybe itll be rediscovering toilet paper next.. poor tony.
It's all relevant and proportional to cid/rpm. Anyways...Right on. I'm going to some beer now.
 
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