I have a 92 Dakota with the 5.2 and replaced the engine because one cylinder was cracked. I have ALL the rotating parts, a good set of heads and the intake from a Grand Cherokee. The original 1992 exhaust manifolds stayed in the truck.

Is the block of a 5.2 similar or the same as what I know as the old 318? If a buildable block shows up, are the mounting points, bosses and bolt patterns (heads, pan, bell housing, timing cover and accessories) going to be the same or am I limited to 88 and later Dodge/Jeep motors?

Mostly curious, but would use an older block if the parts fit.

Steve

 

The 92 was the first Magnum Engine year. Assuming your 5.2 318 is stock and you want to change out as few parts as possible I think you will have to be careful to get those parts from other Magnum engines. There are a lot of engine switch or pull and replace threads on here.

 

318 and 5.2 are the same. The difference, as mentioned, is whether it is a magnum (92 or newer), or LA block. (91 and older) So far as I know, any 5.2 magnum engine should drop right in, and bolt right up. You may have to use your intake manifold though, as EGR went away in 96, and the second coolant temp sensor went away in 98.

 

Think 2nd Gen SBC and 4th Gen SBC.

The motor mounts for the Magnum engine were added; the older blocks won't "just bolt in".

Head oiling on the new blocks is via the pushrods, older blocks via gallerys up into the head to lube the older rocker shafts.

You really need to stick with Magnum parts, as HeyYou said.

But, most of the INTERNAL parts (cranks, rods, pistons, rings, bearings, etc.) are directly interchangeable.

As HeyYou pointed out, you really should stick with 92+ Magnum blocks.

(There's several advantages to the Magnum block; they're thinner walled, so maintain cooling better; better cooling passages inside the block; more flexible mounting; etc.)

RwP

 

THANK YOU Ralph!

That was the point of reference that I needed. I am very familiar with SBC layouts and was hoping that the change was after my block. Now I know that I have the first year of the next Gen block.

One last question. Is the Dodge/Jeep block the same 92-96 or what is the era that I can find a viable block to add my parts into?

Thanks again
Steve

 

FWIW IMO you are better off with the 92-2003 magnum series vs the 91 back.... You get a roller cam, thinner rings, lighter pistons, higher compression, better flowing heads, the list goes on. HP gose from 170? to 230.

 

92 to end of production for the block and heads.

Manifolds changed some due to body and emission standards; oil pan may be different due to body. But you didn't ask about them.

!IF! you're rebuilding one, consider carefully ditching the factory heads. See, the factory Magnum heads outflow ALL factory LA heads (again, think SBC generational differences). But, the Magnums are known for cracking.

Aftermarket, the EngineQuest heads can be had for about $500 loaded with valves, springs, seals etc. Ready to bolt into place and run. (See Jegs or Summit).

Best is, they breath better, but won't need a tune on the ECU to do any good. (Oh, a tune can really wake that old 5.2 up ... but the 92 was not exactly easy to tune.)

RwP

 

Roller cams were introduced when they came out with the tbi setup in 88. My 91 5.2 tbi had a roller cam from the factory. But it still had the LA intake bolt pattern.

 

actually roller cams came out in the old smallblocks in 85. the Diplomat cop cars had them