Can I use 340 (LA) camshaft, lifters, & timing chain in a 360 Magnum?

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69_340_GTS

69_340_GTS

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Got these fairly new LA-340 parts I'd like to use in a new 360 Magnum build. Am I looking for trouble?
 
Yes, but custom length pushrods will be necessary. If it's a solid flat tappet you'll need adjustable rockers, too.
 
69_340_GTS said:
Got these fairly new LA-340 parts I'd like to use in a new 360 Magnum build. Am I looking for trouble?
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Why? Sell the stuff and get the right parts. Magnum is roller lifter, LA is not. Magnum is injected, LA is carbureted. (fuel pump drive) You'll need a LA front cover for the fuel pump drive. Different oil through lifters and pushrods. Scrap that plan.
 
toolmanmike said:
Why? Sell the stuff and get the right parts. Magnum is roller lifter, LA is not. Magnum is injected, LA is carbureted. (fuel pump drive) You'll need a LA front cover for the fuel pump drive. Different oil through lifters and pushrods. Scrap that plan.
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That's kinda what I was thinking, too- it's doable, but why?
 
69_340_GTS said:
Got these fairly new LA-340 parts I'd like to use in a new 360 Magnum build. Am I looking for trouble?
Click to expand...
While most will agree that the use of a LA or none roller camshaft in a Magnum engine is backwards, there is also another train of thought I think others maybe missing. While a roller cam is normally a superior cam on several fronts, there also expensive as well as a set of new lifters should the heavy weight OEM units need to be replaced.

Over all, if you already have all the LA parts needed for the swap, there are two things that need be paid attention to. First, the lifter should be AMC lifters.
(For those that don’t know, the AMC lifters can be used in pushrod oiling applications while the MoPar lifter can not. AMC lifters are the normal lifter given to you with new cam purchases. They have the same .904 diameter as MoPar lifters.)
Pushrod lengths should always be checked!

Secondly the lift should be recalculated by simple math.
The LA cam lift divided by 15 then multiplied buy 16 for the new lift it will see with the rocker change of 15 - 16. you’ll need to check retainer to valve seal clearances and double check spring requirements as it could change.

If you don’t have the all the LA components, they can add up very quickly to equal and possibly surpass the price of a roller cam. Which may not require anymore parts to effectively use.

The draw back of the roller cam is price. While this is a given, there is some variation in prices. The other thing is the Hyd roller lifter is heavy. They will perform well with mild camshafts. Some have done very well here. The lifter cam spin 6000/6500 rpm’s.

I myself have all the parts needed for this swap and may do it myself later. If I had to source everything new, I would not bother. Spare parts from other engines have been stock piled for future use as well as other “stuff” from “buy it all or buy nothing” deals. Not my favorite. But sometimes I can resell what I don’t need/want if there decent enough for use.

I picked up new, never used cams and lifters from time to time at a big cost reduction vs a new set. Just the pushrods will be new.
 
O.K. thanks for the info. Already have good LA heads, Harland Sharp rockes which will oil thru pushrods, AMC type lifters, oil thru pushrods (and yes I know they could be the wrong length). Trying to save several $1000$ if I can use a lot of existing, fairly new parts.
 
Looks like you have the bases covered already.

Are you swapping front timing chain covers?
Is this a engine swap project?
How are you doing fuel delivery?
Have you addressed the engine balance issue?
 
All those parts will fit no problem, I've done it before myself. You might not even need custom-length pushrods since you're using LA heads; there is a slight difference in deck height between Magnums and LAs but that's the only factor I could think of which would influence pushrod length and we're talking maybe .010" or less? If the plan is to swap the Magnum into a classic you'll want the LA-style timing cover anyway, Magnum timing cover puts the accessories kinda high up and looks weird in an old car IMO.

I'd only be concerned about the EFI, roller lifters etc. if I was putting it in a 90s-2000s truck like they came out of.

Engine in my Duster is a 2000 5.9L block+crank+rods+pistons, Edelbrock LA heads and non-Air Gap RPM intake, custom-grind hyd roller cam with long snout for fuel pump drive, reused stock Magnum lifters, LA timing cover, LA double-roller timing set, LA headers, PRW damper with Magnum offset weight, reused Magnum flex plate. Sounds like Frankenstein but it pretty much all just bolted together like any old small block.
 
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start that thread. Ill chime in on the rod little end width. I got stroker pistons for a magnum and they didnt fit LA rods, to narrow. Had to hit the piston pin area with a dremel to clearance them. I cant remember if I found out when I tried to put them on the crank (did not center on journal) or if the rod didnt fit up in there. MP cast pistons
 
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Really, @volaredon ? Name one thing in my statement that is incorrect.
 
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