Magnum Heads/LA block parts list.

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ddart cart

ddart cart

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The flawless 360 magnum steamer I just bought is shot, and being on the road by late may is probably not happening.

I got a line on a bored over 360 la that never got assembled, and I definitely want to buy it.

At that point I will have:
A complete magnum with a bad block 70k
A complete running 1974 5.2 135k
A bored over 360la with crank, pistons on rods, and cam bearings in, no cam.
A new air gap with la and mag bolt up
A new kevco pan and pick up
A fresh rebuilt 650 thunder
A new adjustable chain
A new standard volume oil pump
A full felpro gasket set for magnum
A timing/water gasket set for la

I want to use the magnum heads on the bored over la, which I think requires amc oil through lifters, hollow push rods, and a cam with oiling holes to match? I tried to search the parts and came up confused as usual.

I’m still poor and prefer avoiding $1200 machine shop visits.

Can the crew provide any parts I missed, part numbers, or clarifications for the novice? Is it an expensive endeavor? Should I consider another plan, moving forward?

Thank you in advance,
Doug
 
Before you get ahead of yourself and decide on anything, have the Magnum heads checked- they're prone to cracking. That will decide what the rest of your build should include.
Is the LA360 block you're getting a standard flat-tappet block or a later ('88-92) roller block? That will also help decide on your parts "short list".
 
Professor Fate said:
Before you get ahead of yourself and decide on anything, have the Magnum heads checked- they're prone to cracking. That will decide what the rest of your build should include.
Is the LA360 block you're getting a standard flat-tappet block or a later ('88-92) roller block? That will also help decide on your parts "short list".
Click to expand...
The early magnum heads like to crack between the bowls and not cause an issue, mine are 98. I will check them again though.
The block I’m not sure, and the guy seems super busy.
 
ddart cart said:
The early magnum heads like to crack between the bowls and not cause an issue, mine are 98. I will check them again though.
The block I’m not sure, and the guy seems super busy.
Click to expand...
Depending on the cam you end up using, Magnum heads may need to have the valve guides cut down for retainer/keeper clearance, so they'll end up at the shop anyway...
And speaking of the cam, don't forget that LA cams are spec'ed at the 1.5:1 rocker ratio, and Magnum heads use a 1.6 rocker- so keep that in mind when calculating actual lift at the valve.
 
Why not drop the stuff on top of the 318 instead of buying another motor? It might give up a little to a 360/5.9, but so do those to a 408. And they would all fit on the motor you already have and save you some change. And probably meet your May goal

Then you have time to source a 5.9 at your leisure if you have your heart set on a 5.9.

But I haven’t been following closely, so maybe you have a reason.
 
DionR said:
Why not drop the stuff on top of the 318 instead of buying another motor? It might give up a little to a 360/5.9, but so do those to a 408. And they would all fit on the motor you already have and save you some change. And probably meet your May goal

Then you have time to source a 5.9 at your leisure if you have your heart set on a 5.9.

But I haven’t been following closely, so maybe you have a reason.
Click to expand...
At 135k the 318 should go to the machine shop for $1200, a 360 that does not need machining is way less, and makes more power. I am also only trying to go through this arduous process one time. For now.
 

Professor Fate said:
Depending on the cam you end up using, Magnum heads may need to have the valve guides cut down for retainer/keeper clearance, so they'll end up at the shop anyway...
And speaking of the cam, don't forget that LA cams are spec'ed at the 1.5:1 rocker ratio, and Magnum heads use a 1.6 rocker- so keep that in mind when calculating actual lift at the valve.
Click to expand...
I don’t know what actually will work, but whatever is easiest and cheapest. Rv cam sounds good, but again I have no clue how to jive all these parts.
 
Go to junkyard, buy complete magnum 5.9, put your intake and carb on it.
Drive.

Building an engine and trying to avoid the machine shop is an exercise in futility. If that is your goal, just avoid building an engine.
 
ddart cart said:
At 135k the 318 should go to the machine shop for $1200, a 360 that does not need machining is way less, and makes more power. I am also only trying to go through this arduous process one time. For now.
Click to expand...
I would just do a compression test on the 318 to see what it's pressures are and that they are balanced. If it's good I'd do what DionR said. Depending on what Rpm's you plan on running, you could have a stout little screamer.
 
Does anyone know how my 440 rebuild survived without a machine shop in 1993? I’m having a hard time understanding why every little fart requires me to spread my butt cheeks for some high dollar machine work.
TT5.9mag said:
Go to junkyard, buy complete magnum 5.9, put your intake and carb on it.
Drive.

Building an engine and trying to avoid the machine shop is an exercise in futility. If that is your goal, just avoid building an engine.
Click to expand...
I just tried that route and got a magnum steamer for 800. Generally yards want 500-1000 for 200k engines. I am being offered a block that already visited the machine shop for a great price. If magnum heads are that much of an a hole, I can use la heads, and go slower. Boo hoo. My goal is to not spend unnecessarily. Again, I am poor.
 
Jersey Devil said:
I would just do a compression test on the 318 to see what it's pressures are and that they are balanced. If it's good I'd do what DionR said. Depending on what Rpm's you plan on running, you could have a stout little screamer.
Click to expand...
The 318 also has white in the oil. I wouldn’t bother checking compression with that situation. It needs to be rebuilt
 
ddart cart said:
just tried that route and got a magnum steamer for 800.
Click to expand...
I read your other thread, did the seller offer to make it right for you? Generally yards selling running good condition **** will stand by that. I agree you got a steamer but they should exchange that one without too much fight. The last one (of many, many magnums) I got complete and running, harness, computer, TB to pan for 700 with 91,000 miles on it. There’s lots of those out in the yards.
 
I think we all understand the need to keep costs down. We've all been there at some point. If you're that strapped for cash though, you may not want to ask for input if you can't handle the answers you're gonna get.
 
Remember, you started this thread asking about piecing together a non-stock engine combination. Did you honestly think there may not be machine work involved?
ddart cart said:
Does anyone know how my 440 rebuild survived without a machine shop in 1993? I’m having a hard time understanding why every little fart requires me to spread my butt cheeks for some high dollar machine work.
Click to expand...
I'm assuming the 440 was pretty much a ring, bearing and gasket rebuild. All factory parts that were designed and engineered to work together; and more than likely left the factory together. Different scenario entirely.
You asked about screwing a set of Magnum heads onto an LA block, which is doable but requires some rework, and if you don't want to check for crack-prone heads, then prepare yourself to do it all again.
ddart cart said:
I am also only trying to go through this arduous process one time.
Click to expand...
Then do it right.
You're trying to mate parts that were not meant to go together, so to be successful you need to be sure the parts are going to work.
Getting snarky with those who were trying to help isn't going to change anything (even though that's been deleted).
Otherwise, good luck.
 
ddart cart said:
The flawless 360 magnum steamer I just bought is shot, and being on the road by late may is probably not happening.

I got a line on a bored over 360 la that never got assembled, and I definitely want to buy it.

At that point I will have:
A complete magnum with a bad block 70k
A complete running 1974 5.2 135k
A bored over 360la with crank, pistons on rods, and cam bearings in, no cam.
A new air gap with la and mag bolt up
A new kevco pan and pick up
A fresh rebuilt 650 thunder
A new adjustable chain
A new standard volume oil pump
A full felpro gasket set for magnum
A timing/water gasket set for la

I want to use the magnum heads on the bored over la, which I think requires amc oil through lifters, hollow push rods, and a cam with oiling holes to match? I tried to search the parts and came up confused as usual.

I’m still poor and prefer avoiding $1200 machine shop visits.

Can the crew provide any parts I missed, part numbers, or clarifications for the novice? Is it an expensive endeavor? Should I consider another plan, moving forward?

Thank you in advance,
Doug
Click to expand...
Depending on the cam kit, the lifters may or may not send enough oil thru' the pushrods, since You don't have one yet, that should be spec'd up front to whomever is supplying them. You already know about the pushrods,.......as stated, go easy on the lift specs, shortening tbe guides is pretty straight forward, but needs checked/corrected, & decent valvesprings need to be considered/acquired depending on what You choose.
*EDIT* I meant to add that You need to check the compatibility of whatever pistons are in the LA with those Magnum heads, get the part# & the piston crown to deck height.
 
Last edited:
ddart cart said:
The flawless 360 magnum steamer I just bought is shot, and being on the road by late may is probably not happening.

I got a line on a bored over 360 la that never got assembled, and I definitely want to buy it.

At that point I will have:
A complete magnum with a bad block 70k
A complete running 1974 5.2 135k
A bored over 360la with crank, pistons on rods, and cam bearings in, no cam.
A new air gap with la and mag bolt up
A new kevco pan and pick up
A fresh rebuilt 650 thunder
A new adjustable chain
A new standard volume oil pump
A full felpro gasket set for magnum
A timing/water gasket set for la

I want to use the magnum heads on the bored over la, which I think requires amc oil through lifters, hollow push rods, and a cam with oiling holes to match? I tried to search the parts and came up confused as usual.

I’m still poor and prefer avoiding $1200 machine shop visits.

Can the crew provide any parts I missed, part numbers, or clarifications for the novice? Is it an expensive endeavor? Should I consider another plan, moving forward?

Thank you in advance,
Doug
Click to expand...
Here is an article about putting the Magnum heads on the LA block and things to look out for and needed.

https://www.hughesengines.com/TechArticles/2magnumlaheads.php
 
Don't be afraid of the machine shop. To do a rebuild right you need them. Even if you're able to hone it and put standard size parts back in it.
 
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