LA’ing a Magnum

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74Dusted

74Dusted

Stock Piler of 340's
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Oh yeah, this one is backwards.

The old 5.2 Magnum from my Dakota is getting a full LA treatment, it’s one of the early production 5.2’s that still had the oil ports to provide oil to the heads & rockers.

Tossing out the Roller Cam & Lifters (half of the lobes are gone on the cam and a few of the roller Lifters have chunks torn out of the rollers), To outfit her with a small hydraulic LA Cam & Lifters & a set of shaved 1.88 Valve J Heads. Gonna use it to power my ‘76 Ramcharger after a rebuild.

I can’t imagine there’s anything that would prevent me from running an LA Cam/Lifters/Pushrods and LA Top End on the 5.2 since it’s one of the early production blocks with the oil ports intact. Anyone know if there’s anything that might prevent the backwards swap?
 
The only other oddity would be the engine mount pads , your magnum will have provisions for old style mounts and the mid mount style... that just might interfere with certain exhaust selections (headers), nothing a side grinder couldn't take care of.
 
If he has the mid mount engine pads, they should clear but it is always worth a quick check before installation.

There shouldn’t e a swap problem.
 
Check the oil passages to make sure it intersects with the cam journal. Sounds like the block needs a through cleaning.
 
Fuel pump? Did the Magnum use a electric?
 
rumblefish360 said:
If he has the mid mount engine pads, they should clear but it is always worth a quick check before installation.

There shouldn’t e a swap problem.
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Nothing fancy on the exhaust, just a factory set of manifolds (it’s going in a ‘76 Convertible Ramcharger). I don’t see stock manifolds possibly hitting the mid mount pads, lol.

Demonic said:
Check the oil passages to make sure it intersects with the cam journal. Sounds like the block needs a through cleaning.
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I did check that to be sure. Definitely getting cleaned out at the machine shop, don’t want metallic cam sludge wiping out a fresh motor.
 
74Dusted said:
Oh yeah, this one is backwards.

The old 5.2 Magnum from my Dakota is getting a full LA treatment, it’s one of the early production 5.2’s that still had the oil ports to provide oil to the heads & rockers.

Tossing out the Roller Cam & Lifters (half of the lobes are gone on the cam and a few of the roller Lifters have chunks torn out of the rollers), To outfit her with a small hydraulic LA Cam & Lifters & a set of shaved 1.88 Valve J Heads. Gonna use it to power my ‘76 Ramcharger after a rebuild.

I can’t imagine there’s anything that would prevent me from running an LA Cam/Lifters/Pushrods and LA Top End on the 5.2 since it’s one of the early production blocks with the oil ports intact. Anyone know if there’s anything that might prevent the backwards swap?
Click to expand...

The forward motor mounts are basically the same as the LA, but will need a little spacering?:D just like we would normally have to do if you don't get a specific mount.
One of the mid mount pads had to be cut off because one of the header tubes hit it not letting the header flange sit flat to the head.
 
toolmanmike said:
Fuel pump? Did the Magnum use a electric?
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Yeah it did have an electric pump originally. I plan on running an LA flat tappet hydraulic cam (with eccentric), LA Top End, LA Timing Cover & Accessories, basically everything LA minus having a Magnum Block & Rotating Assembly underneath all of it.
 
TrailBeast said:
The forward motor mounts are basically the same as the LA, but will need a little spacering?:D just like we would normally have to do if you don't get a specific mount.
One of the mid mount pads had to be cut off because one of the header tubes hit it not letting the header flange sit flat to the head.
Click to expand...

That’s not actually a problem, I shouldn’t need spacers or shims, if I remember correctly the Magnum uses the 340/360 style forward mounts. My Ramcharger originally had a 360 (long story, let’s say I’m no longer friends with someone), so I still have the mount brackets for it.
 
Curious as to why you wouldn’t stay with a roller cam? I was under the impression that was one of the big reasons people like to switch to Magnums. (Besides availability.) Educate me before I potentially go down the wrong path.
LA top end, certainly
 
One thing I don't like about rollers is the lifters are gigantic and HEAVY. That has to make a difference

Isn't the deck height/ etc different? How does that affect your compression ratio? I know you put mag (EQ) heads on an LA you gain a bit
 
67Dart273 said:
One thing I don't like about rollers is the lifters are gigantic and HEAVY. That has to make a difference

Isn't the deck height/ etc different? How does that affect your compression ratio? I know you put mag (EQ) heads on an LA you gain a bit
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Roller size; I pick up what you’re putting down
Compression; Isn’t that primarily from chamber differences?
 
RogerRamRod said:
Roller size; I pick up what you’re putting down
Compression; Isn’t that primarily from chamber differences?
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The deck height is supposed to be different between mag and LA

I don't know what you mean "pick up what you are putting down". It takes more spring to put them back down, simply put. They are heavier. My new engine is a LA roller and they may or may not come back out of there, later on
 
I’m picking up what you’re putting down
Translation
I understand what you’re saying
 
You're lucky lol I'm having to do external oiling to make some Edelbrock LA heads work on a late 5.9L Magnum block. Pretty straightforward other than that, might have to mill the intake faces to make the holes line up. I'd recommend taller pistons to go with those J heads as well, what is the chamber volume on those?

@RogerRamRod Usually if you can get a Magnum short block in good shape (I pulled one out of a 2001 Ram 1500 at the junkyard) the roller lifters can be reused and the stock cams in both the 5.2 and 5.9 are much better than the stock LA truck cams. I got a custom roller Racer Brown grind for mine since the stock lifters are in great shape but replacements are expensive. Also factory machining tolerances were a lot better on the Magnums and they had much lighter pistons, most of all the multi-port EFI keeps the cylinders fresh even after 150k+ miles unlike carb'd engines getting raw gas poured down the intake on cold starts from acc. pump, choke running too long, messed up carbs leaking fuel etc.
 
MOPEkidD-3 said:
You're lucky lol I'm having to do external oiling to make some Edelbrock LA heads work on a late 5.9L Magnum block. Pretty straightforward other than that, might have to mill the intake faces to make the holes line up. I'd recommend taller pistons to go with those J heads as well, what is the chamber volume on those?

@RogerRamRod Usually if you can get a Magnum short block in good shape (I pulled one out of a 2001 Ram 1500 at the junkyard) the roller lifters can be reused and the stock cams in both the 5.2 and 5.9 are much better than the stock LA truck cams. I got a custom roller Racer Brown grind for mine since the stock lifters are in great shape but replacements are expensive. Also factory machining tolerances were a lot better on the Magnums and they had much lighter pistons, most of all the multi-port EFI keeps the cylinders fresh even after 150k+ miles unlike carb'd engines getting raw gas poured down the intake on cold starts from acc. pump, choke running too long, messed up carbs leaking fuel etc.
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That’s a big reason on downconverting to the LA Flat Tappet Cam & Lifters. Replacement Magnum Roller Lifters are priced like they’re made out of Gold & Platinum with Unicorn Tears for assembly lube. And the lifters/Cam in this 5.2 are wrecked.

Sadly, this isn’t a one time occurrence for me. The Mid-80’s Roller Cam LA 318 that I picked up to build a Stroker for my Dodge D50 also has flat lobes and trashed lifters.

Don’t remember the chamber size on the J’s off hand, but that’s easy to measure. I had them shaved about 15 years ago and ran them on a 318 in a Dodge D50 and then the engine gathered dust in the shop and eventually became parts for other engines.
 
74Dusted said:
That’s a big reason on downconverting to the LA Flat Tappet Cam & Lifters. Replacement Magnum Roller Lifters are priced like they’re made out of Gold & Platinum with Unicorn Tears for assembly lube. And the lifters/Cam in this 5.2 are wrecked.

Sadly, this isn’t a one time occurrence for me. The Mid-80’s Roller Cam LA 318 that I picked up to build a Stroker for my Dodge D50 also has flat lobes and trashed lifters.

Don’t remember the chamber size on the J’s off hand, but that’s easy to measure. I had them shaved about 15 years ago and ran them on a 318 in a Dodge D50 and then the engine gathered dust in the shop and eventually became parts for other engines.
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I'll just be dumping some fresh Brad Penn over mine and priming the oil system thoroughly. Yeah the factory roller cams all seem to be low-quality metal with thin surface hardening even up through the modern Hemis, I got a 2014 5.7L with only 134k for cheap because it wiped a cam lobe and ate a lifter roller.

BTW I see you're in Lewistown, I grew up in State College... and no I'm not a football fan LOL
 
MOPEkidD-3 said:
I'll just be dumping some fresh Brad Penn over mine and priming the oil system thoroughly. Yeah the factory roller cams all seem to be low-quality metal with thin surface hardening even up through the modern Hemis, I got a 2014 5.7L with only 134k for cheap because it wiped a cam lobe and ate a lifter roller.

BTW I see you're in Lewistown, I grew up in State College... and no I'm not a football fan LOL
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I’m not a football fan either, people ask me that question all the time.

“Did you catch the PSU game last night?” “No, I don’t watch football. I spent my night building a rollcage, more productive.”

Along with the famous question “How’s the seven mountains today? Can my car make it up in the snow?”
 
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