Quote:

Originally Posted by ol' grouch

I'm not sure. I just go by the last number. If it ends with a 9, first generation. If it ends with a 7, second gen. The 5.2 is an oddball first gen.

Wow, I just cant set and let this mis-information go unchallenged.......

To Begin
1. 318 and 360 are cubic in displacement (CID)
2. 5.2, and 5.9 are displacement measures in Litres.
3. 318 = 5.2
4. 360 = 5.9
5 What most call first gen. is also called LA style engines. They started production in the 60"s and continued through 91 for the 318 (5.9) and through 92 for the 360 (5.9)
6. The second gen. is the Magnum series. In V-8 they were produced from 92 through 03 for the 5.2 and 93 through 03. for the 5.9
7. There is only one gen. of magnum engines.
8.For a lack of better words, The magnum is basically an improved version of the LA series engines. IMO the changes were made to take advantage of the newer multi port fuel injection. Some of the changes are as follows.
a. Lighter weight pistons.
b. thinner rings.
c. higher compression
d. better flowing heads
e better flowing exhaust manifolds.
9. However, a lot of parts interchange between the 2 series..... and for the purpose of modifying the motor, much is the same. Here is a list I can think of.
a. timing sets
b. rotating assemblies for the purpose of stroking the motor interchange
c. camshafts interchange, but be aware. the magnum cam does not have the provision to drive the fuel pump.
d. heads can be interchanged with oiling mods, along with the correct rockers, etc.
10. The 5.7 engine is "what I believe " considered the 3rd gen Hemi. There is absolutely nothing, in common, with the magnum engine...... It is a totally different design.

In closing, I want to add the following.
1. I apologize for such a lengthy post, but feel it necessary to correct bad information that a newbie may take as fact.
2. This forum has been the best source of good information I have found for modifying and repairing my 87 dakota.
3. 99% of the people on here, post good information, with good intentions to help others.
4. None of us are always correct, so consider that, and fact check what you read.

 

The cams won't interchange. The carb. LA were hydraulic flat tappet, the TBI version was a hydraulic roller cam, both with 1.5:1 ratio shaft mounted rockers. The Magnum heads are pedestal mounted 1.6:1 ratio. Magnums oil through the pushrod. LA oiled through the shaft on the rockers. Intake bolt pattern is different. LA was at an angle, the Magnums are straight. LA valve cover is 5 bolt, Magnum is 10 bolt, but you can bolt the LA valve covers on the Magnum heads with an LA gasket. Minor changes on the oil pans, you can only use a 1 piece pan gasket with the Magnum pan, it won't work on the LA pan. I believe it's the rear bearing recess is a different geometry. The Magnum engines mounted differently in the 2nd gen trucks, than the LA mounted in the first gen trucks. Magnums also have the bolt holes in the right rear of the block for the crank sensor. LA heads will work, but they need to be drilled for the oil return, and an LA timing cover must be used, Magnum accessorie brackets won't bolt to the LA heads just an fyi if you want to keep the serpentine belt. LA exhaust manifold bolts go into the coolant ports and will leak when you pull the exhaust stud out, Magnum heads are dead holes.

 

Quote:

Originally Posted by rebeltaz83

The cams won't interchange. The carb. LA were hydraulic flat tappet, the TBI version was a hydraulic roller cam, both with 1.5:1 ratio shaft mounted rockers. The Magnum heads are pedestal mounted 1.6:1 ratio. Magnums oil through the pushrod. LA oiled through the shaft on the rockers. Intake bolt pattern is different. LA was at an angle, the Magnums are straight. LA valve cover is 5 bolt, Magnum is 10 bolt, but you can bolt the LA valve covers on the Magnum heads with an LA gasket. Minor changes on the oil pans, you can only use a 1 piece pan gasket with the Magnum pan, it won't work on the LA pan. I believe it's the rear bearing recess is a different geometry. The Magnum engines mounted differently in the 2nd gen trucks, than the LA mounted in the first gen trucks. Magnums also have the bolt holes in the right rear of the block for the crank sensor. LA heads will work, but they need to be drilled for the oil return, and an LA timing cover must be used, Magnum accessorie brackets won't bolt to the LA heads just an fyi if you want to keep the serpentine belt. LA exhaust manifold bolts go into the coolant ports and will leak when you pull the exhaust stud out, Magnum heads are dead holes.

A lot of this is being done on sites such as forabodiesonly.com. Do a search in the magnum swap and small block mopar section.

Going to hit a few of your points.
1. Cams wont interchange. Blueprint engines are selling these now, converted. Notice in the picture,by the valve covers it is a magnum. https://blueprintengines.com/product...tor-bpc4082ctc
2. Oil pan, you can use a 360LA oil pan on both the 5.2 and 5.9 magnum. https://www.forabodiesonly.com/mopar...il-pan.365546/
3. mounts, la head on a magnum block, and magnum heads on a la block can and has been done. Again, if you choose to research the attached forum, you will find examples.....

My intention in post 21 was to show the magnum, (5.2 & 5.9) are very similar to the LA (318 & 360) The 5.7 hemi has nothing in common other then the brand.

 

The "magnum" name was used before the "magnum engine" witch can be confusing to some.



The 1970 340 AAR-T/A motors(LA) had 10.3:1 compression. No 318/360(magnum) came with that high of a compression ratio.

This is key!!!

 

Quote:

Originally Posted by Moparite

The "magnum" name was used before the "magnum engine" witch can be confusing to some.




The 1970 340 AAR-T/A motors(LA) had 10.3:1 compression. No 318/360(magnum) came with that high of a compression ratio.


This is key!!!

Ill stick by what I said for the following reasons.
1. The comparsion made by the post i quoted said, "I'm not sure. I just go by the last number. If it ends with a 9, first generation. If it ends with a 7, second gen. The 5.2 is an oddball first gen."
2. Since the quote was 5.2, 5.9, and 5.7, all truck engines,the statement concerning the 340, that was never put in a factory trucks, IMO does not apply.

Again, I dont want to get into a comparsion of nit picking.
But when someone keeps posting BS that is grossly false, it blows all credibility of this forum being a good source of information if it goes unchecked. And this is not the first. Just do a search with his name.....
Again, please read what he wrote, and to save you time, here is copy and paste.
"I'm not sure. I just go by the last number. If it ends with a 9, first generation. If it ends with a 7, second gen. The 5.2 is an oddball first gen."

Oh, and just to add, didnt know anything was oddball about a 5.2 magnum or a 318!! LOL Did you? I thought they were 2 of the most common motors used during their era.

 

I've been all over this stuff, I put a 360 Magnum in my 91 D150. I kept the V belt drive, and I used LA valve covers, but I wanted a 1 piece pan gasket so I kept the Magnum pan. Pan gasket is different but yes the pans will swap over if you use the correct gasket. Everything will swap over it just needs some work, to make it work correctly if you Mish mash Magnum with LA parts lol. Wasn't 03 the only year they gave the 5.7 the Magnum monicker?? I thought it was stupid, because of the fact it shares nothing with the 318/360 Magnum.

 

I wonder if he ever got it running?

 

the Magnum Engines have the same front ears as the LA Engine so it can be installed in older cars/trucks