possible 360 build

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volaredon

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I have a 2000 360 block here (Magnum engine) It had been completely rebuilt including hot tank, 30-thou overbore, new cam bearings and freeze plugs, polished crank, all new bearings, new oil pump, new roller lifters, and more. No line boring or anything like that though. this engine wound up a stack up of errors. It was a Craigslist "used engine" buy, that was rebuilt to replace the original 258K mile Magnum 360 that came out of my Durango. I had never heard it run upon buying, took it apart immediately for rebuild upon buying it.
Upon break in, I had an injector (or 2) stick wide open, brand new cat went red and plugged, break in oil came out as a slurry of bearing material. the excess fuel "washed out" the engine and diluted the oil. also #4 exhaust valve stuck, on BRAND NEW set of EQ heads, installed out right out of the box. I made the mistake of "assuming" they would be fine, as I received them.

Machinist said that #4 exhaust, wasn't the only tight valve in those heads, when I took them in to "see what happened" before putting them onto the engine that is now in that rig. Poor assembly by EQ. he had to pound out most of the intakes too. and also that this was not the 1st time that he has seen this on new, out of the box Small block Mopar EQ heads, either.
less than 6 road miles on this engine since rebuild, and roughly 3 hours (max) run time on it, and it got yanked. been waiting for engine stand-space to get it up on stand and apart. I figure at a minimum, all new bearings again throughout, maybe another round of hot tank and bottle brush, a hone, and another set of rings.
this was far from my "1st rodeo" in engine rebuilding, but all the problems I have ever experienced upon a rebuild showed up on THIS build for some reason.
My son has an LA 360 (76 I believe) that was also rebuilt not too long ago. also 30-over, but Federal Mogul flat top pistons with valve reliefs, would be a bump on CR over stock-replacement Magnum pistons. about 6k miles on those parts out of my son's engine. He has the LA crank, rods, and the described pistons. he decided 360 cu in wasn't "good enough" and decided to turn his 360 into a 408. 1 summer's worth of driving in a Ramcharger, mostly highway.
My question is, can I use the LA crank, rods and pistons, in a magnum block? I had thought that, if it would all bolt in, to take those LA parts and see what it would cost me to have them internal balanced, such as a 318 is....
but maybe possibly just install the LA parts as they are and just use a LA 360 converter and harmonic balancer... would definitely re ring those pistons, before install.

If this is possible to bolt in the LA rotating assembly into the Magnum block there is still the issue of finding a set of good, uncracked heads to top it off... story for another time.
 
So if you have a complete engine, why not just go through it? Are the EQ heads salvageable? LA 360 and Mag 5.9 are balanced differently, is that why you way to use the 360 rotating assembly or just because it has .030 pistons (which may or may not work)? What is the end goal?
 
Yes the LA crank etc will bolt in no problem of course as you stated you have the balance issue.
 
So if you have a complete engine, why not just go through it? Are the EQ heads salvageable? LA 360 and Mag 5.9 are balanced differently, is t
hat why you way to use the 360 rotating assembly or just because it has .030 pistons (which may or may not work)? What is the end goal?
I bought the EQ heads for the original build and they were built with too tight valve guides .
When I discovered a slurry of metal in the original engine that I rebuilt, I went and got another engine and dropped it in. I took the eq heads off figuring that I would get my money's worth out of them one way or another
so being as how I decided to replace all of the gaskets and freeze plugs in the 2nd engine anyway I wanted my new EQ heads on the Durango they were bought for. So the EQ heads are on the 2nd engine that I got for the durango, which my wife is driving daily.
I took the heads from that 2nd engine to the machine shop for checkout and discovered that they are cracked and were deemed junk by the same machine shop that I had fix those defective EQ heads.
Being as how I had a valve stick and kiss a piston, I don't want to take a chance on it being cracked from the collision with the valve
The Pistons in that motor are also new with 6 miles on them, 3 hours max run time/ they are also 30-over, like the ones from the LA engine. But the ones that are in the LA 360 are flat tops. Which the stock replacements in the magnum now are dished as the original stock ones were.
I'm gonna be buying new rings for which ever Pistons I put into the block, the flat tops are collecting dust and won't be used anyway so I thought I could make it a better engine with a little more compression by using the flat tops. They're here, might as well use them in something if I can.right?
 
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The end goal is to get as good an engine as I can get using up what I have around.
Like I said at the moment I do not have a good uncracked set of magnum heads on hand so whatever I do I will need to get some
Considering that, I may decide to go aluminum, still thinking about that.
I thought I'd answered your questions in my op but hopefully my 2nd post spells it out a bit clearer
 
clear
looks like al time with no EQ- maybe later -and Magnum RT hard to find
get bare al and have one of our members or your machine shop load them with known quality parts
(at whatever level quality is to you)
don't go buying a cam till you kow your cr
build for tight quench
what ft pistons?
bvvc you may need dished pistons depending on the head ccs
get it all figured out before buying anything
if money is a problem you can make the magnum pistons work better than the way down the hole la pistons
cheers
 
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. I'll try to get the numbers off the flat tops and see just what they are
I remember when they were bought they were supposed to be higher comp height than stock la pistons they are flat top with 4 valve reliefs much better looking than the stock POS dished pistons that came out of that la 360. Were supposed to be 9:1 with stock 70s 360 heads as I remember.
I want to build a 360 without the damn dished pistons.
 
ok you own the ft pistons - let's make them work
measure the ch and lets check the cr
I think you ment post 4 not 2 above
 
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yeah I have the flat tops and I have the replacement Magnum style pistons, both 0.030 over, both very little use.
but I am afraid of possible as yet unseen damage possibly to the piston out of #4 that crashed a valve..... I know the flat tops have not seen that sort of issue. both sets of pistons are Federal Mogul brand. I would like to combine what I have to the best engine I can hope to have..... I do like the potential of being roller cam ready being a Magnum block...
I have a cam here (an MP one that they don't make any more) I have to get the numbers from it yet again, once the Magnums came out people on the Dodge truck sites used to call it a "sausage" cam.... it was the cam that all the magazines used to advertise with an MP computer and MP shorty headers to take your "235hp" 360 Magnum to 300HP.... not saying this is the cam I will pick, just that I have it.... in fact I have a 2nd roller cam for a 360, a buddy bought it for his 408 build then decided that it was "too small" for the 408 but would be "good" for a 360 Mag...
as I remember thinking that one might be a little too radical for what I'd want.... again my knowledge of cam numbers and how one number effects what is a little foggy..... I have a thread on the B boy site right now about that very subject on a cam for a 318 in another of my cars...… I need to find some fundemental "cam-educ.," info..... so I can be more informed and be easier to pick my own..... ever since the 318 that I built for my Cordoba about 1986-87ish that was dependable but a bigger slug than it had been stock, I have been very "cam-shy" and have tended towards either reinstalling the original cam or if there was a reason the cam had to be replaced (wear, etc) I have tended towards a stock replacement or "baby steps" above that level.
but for this topic I'm far away from cam choice. Unsure yet whether this will end up in the Durango like I originally intended, in my 96 Dakota 4wd or possibly my 85 D150 in place of the /6 or my 80 Volare….. what I put it into will have to be decided before I decide on a cam. right now just trying to make use of some more stuff that I have laying around.
are there any aluminum aftermarket heads for a Magnum block that come drilled for an LA intake, as the EQ's could have been had? If this engine found its way into the Volare or the D150 it would definitely stay carbureted.
but lets hold off on that sort of discussion here, right now just wanting to get the short block safely together. the top end can be another discussion later.
 
get all the info on those cams and post back
where did you say there is a thread
the sausage cam was about the largest you could run with the early single board computer
later computers can be reprogrmmed
 
What about the idea of having the crank out of the LA engine balanced for internal balance? Worth doing?
 
You would have to measure it to be sure. But I think the magnum block has a little shorter deck hight than the 360 LA bock. If so the LA pistions will stick out of the block. How much i am not sure.
 
Might have already asked but haven't seen an answer if so sorry for the repeat
I mainly want to use the flat tops in the magnum block. What's it take to get a crank balanced neutral instead of external?
I can go with either the LA or a magnum 360 crank. And do I use the magnum or the LA rods? Or would it matter?

I Know that you can use LA pistons or crank or rods, in a 318, either magnum based or LA based.
The casting number of the 318 crank is the same from 1968 and up. LA and magnum. But from what I understand the amount of Imbalance is different from the magnum 360 to an LA 360.
I have this conglomeration of 360 parts collecting dust that I'd like to put to good use instead of continuing to collect dust, but I like the idea of neutral balance in case it gets stabbed in in place of a 318 or even a 6 cylinder.
 
I like the idea of neutral balance in case it gets stabbed in in place of a 318 or even a 6 cylinder.
Not sure this is Required, because
#1 you can't use the slanty trans anyway
#2 whatever TC you use can be carried over to the next trans, so long as you stay with the basic capacity. Or you just use a correctly weighted flex-plate and carry that over to anything.
The only time that you run into a snag is when changing from an auto to a manual trans. But even that is not a really big deal; you just get whatever flywheel you have, balanced to your correctly balanced flex-plate.
 
I totally get your dilemma.
I too,would totally like to use the flat-tops
if
they come up; close to, or out of, the decks.
But if not then,whatever; and I wouldn't lose sleep about balancing at this point. First I would mock it up and measure the deck-clearance, to see what's what.

Internal balance is pricey, and for a streeter, I don't see an issue with bolt-on balance. The LA slugs are not That much different from the Magnums,so it should not be too difficult to make bolt-on weight work.
And if you have to take some metal off the tops of the LAs to fit into the Magnum, that would be moving in the right direction. So;
First I would mock it up and measure the deck-clearance, to see what's what.
 
Not sure this is Required, because
#1 you can't use the slanty trans anyway
#2 whatever TC you use can be carried over to the next trans, so long as you stay with the basic capacity. Or you just use a correctly weighted flex-plate and carry that over to anything.
The only time that you run into a snag is when changing from an auto to a manual trans. But even that is not a really big deal; you just get whatever flywheel you have, balanced to your correctly balanced flex-plate.
Not saying that it may end up in place of the slanty, but it could. I know that the Bell housing for a slant won't fit a small block, if that is where this engine winds up in I have both a SB 727 and I think I still have a 518 here too, that would take care of that issue.
It might end up in my volare. Which has no engine currently. If it does then it will be in front of a stick trans of some sort.

Or it could end up going into my 96 Dakota 4wd as it's current 318 is gettin tired with almost 230k on it.
Or it could go into the durango that it was originally put together for in the 1st place.
 
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