magnum 5.9 vs LA 360

[Ed Dorey]

I've read that stroker kits fit either of these motors but am wondering about cams and other performance parts. I plan to use Enginequest heads regardless what way I go so that I can use the LA style intakes. I haven't seem many performance cams for the magnum motors tho. Will the LA style cams work in the magnums? Was thinking of going to a roller cam if possible.

 

[80mirada]

You can use cams intended for an LA.

 

[XfbodyX]

If you look on ebay there is a guy who sells reground hydro roller cams in the 150-170 area for any config, LA Premag Roller with long snout for fuel pump or no snout, mag, ect...

ezcondition | eBay

Ive bought three from him and the quality is great and even better if you use a la block and retro fit lifters the regrinds get the most taken off the base circle which helps ensure non of the lifters uncover at max lift.

If you hunt a pre mag roller block, you can use oem $110 mopar roller lifters and oem dog bones and spyder and so its a killer setup on the cheap.

 

[BudW]

We need to step back a moment. Everyone might be on the same page (or maybe not).
I will go over it for those new to this topic.

I will prefer to use the term “Pre-roller cam vs. Roller camshaft”, instead of “LA vs. Magnum”.

In 1985 all 318’s went to roller camshaft. 360’s (trucks) went to roller camshaft the next year.
The roller blocks have longer lifter holes and have a provision for the roller lifter hold-down.
If a person wants roller lifters, I would start with a ‘85-up 318 or ’86-up 360 LA or Magnum block.
The LA-Roller cams and Magnum camshafts are ground a bit different (lobe profile) – but for all practical purposes they are interchangeable.

All small blocks use the same camshaft “blanks” and are ground differently to the style engine and if performance version (or not).
Different camshaft styles are:
Poly (’66 and older) - which have a different lobe center and use an ieieie pattern instead of eiieeiie pattern.
LA non-roller – ’64 to ‘84/85 (with different performance grinds).
LA roller (‘85/86 to ‘91/92).
Magnum (‘92/93 to ’03).
Note: the split year, like ‘85/86 – the first number is for 318 and second number is 360.

Note: a person could install a non-roller camshaft (and lifters) into a roller block – but not sure why a person would do so.
BudW

 

[Oldiron440]

My buddy's at the engine shop are having trouble with the retro roller cam lifters in the earlier sbm blocks. Lifter blead down has been the largest problem.

 

[XfbodyX]

Bud its my understanding that the some of the 318s in 85 came with roller cams and some flat tappet cams even in a the newer roller cam block. Ive popped many 85 318-s open to find a flat tappet hydro cam/new style roller block. In 86 the 318 trucks got the roller and if I recall the 360 pre mag roller block did not show up until 1988 casting numbers. Ive never seen in person or a pic of a 360 la roller block dated prior to 88. But ive been wrong before.

Early roller cams had the snout for the fuel pump, then the early FI cams had no snout. The one I posted has the snout for mech. fuel pump.

Many people use the roller cam blocks with flat tappet cams since a hydro roller still cant match some of the higher performance flat tappet cams and even more simple the overall cost in the end.

For people not well versed in the big confusing picture of the odd transitional years id not glean all my info from one person or one site, google is your friend and for one person even with 100% info it would take alot to type it all out so its much easier to spend a good night on google and sites like fabo, ramcharger central are just a couple good places the search engines will lead one to, magnumswap.com is really good.

Even wiki isnt perfect..... I just read this "Some police package cars came from the factory with a steel crank and h-beam rods.[3] There was also a "lean burn" version of the 360."...... Well id love to crack open a sledged up old police engine and find a steel crank and h beam rods but its not going to happen.

During the transitional years it was so easy to have two or three parts with the exact same casting number and exact same look but have fine refinements for roller/non roller that made them non interchangeable. Here is an example of two nos 1985 heads from the box, same PN, one has the larger pushrod holes for the roller motors, one fits la. One can work on both, the other is roller specific.

 

[BudW]

XbodyX – I would agree with you on most everything you said.
Around that timeframe, I wasn’t working inside of the engines that much as much as I was transmissions.

I had seen a few roller blocks without roller lifters – which is why I mentioned it, above. Not sure why they were made that way and never did ask (but a person could assume a lot of things).
Note: not on vehicles I worked on, just one’s other technician would be talking about either as walking by, or sometimes rather loudly (if no one was paying attention to him).

To be honest – I wouldn’t know the difference on camshafts (which goes to which engine) – for not really had more than one cam in front of me at any one time.


Rogers county (Oklahoma) did order a bunch of 360 police engine M-body’s (straight from Chrysler fleet sales, not the dealership). They were shipped into my dealer for new car prep. I do know our dealer wasn’t happy about being outside of the loop. I think this might have been late ’84 (so ’85 MY) – but I can’t remember. I saw the cars – but didn’t get any closer than 20 feet from any one of ‘em. I’m not even sure if they were real 360 cars (you know how “office” story’s go, sometimes).

Honestly, I have only been inside of two different 318 police engines. One was to replace an oil pan gasket – when I discovered they had windage trays inside. The other is intake (only) off the ’84 police engine inside of my garage (which is how I got that engine/car).
I can’t confirm or deny what police internal parts look like – other than my ’84 police engine does have large port heads on it (and does appear to be untouched, other than intake).
I tossed a ’72 340 intake on it to test fire the engine – but could never get that engine started.


Don’t get me going about casting numbers.
A Chrysler District Service Manager showed me a book he had to carry around – about casting numbers. He said this data was never meant to be used – except by the machinists at Chrysler (which made me wonder, why he was carrying the book around . . .). They purposely used casting numbers on parts, so they would not be the same as the official part numbers), so they could use one casting for multiple versions of parts – depending on needs. A good example would be cylinder heads could be machined with A.I.R. ports or not machined at all. Another would be, your example.
BudW