How to ID a real MP 360 crate magnum, id the HP rating, and what's it worth?

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67Dart273

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Someone is advertising a new Mopar crate 360. Has the black aluminum Magnum covers. "In the crate." Has a partial photo of the MP literature, and what would I pay?
 
If it’s a real one there will be a part number on the crate. May also be a yellow sticker on the block with part number.

All 380 Magnum crate engines from Mopar had an M1 single plane intake.
All lower power (300 I think) Magnum crate engines from Mopar had an M1 dual plane intake.

It’s worth whatever someone is willing to pay.
 
wasn't the part number also stamped on the rear of the engine? behind the dist where the bell housing bolts up.
 
If it’s a real one there will be a part number on the crate. May also be a yellow sticker on the block with part number.

All 380 Magnum crate engines from Mopar had an M1 single plane intake.
All lower power (300 I think) Magnum crate engines from Mopar had an M1 dual plane intake.

It’s worth whatever someone is willing to pay.
Let's put it this way: Does anyone make th eequivalent and what do they cost and weren't these all new parts AKA not rebored used blocks, etc?
 
Someone is advertising a new Mopar crate 360. Has the black aluminum Magnum covers. "In the crate." Has a partial photo of the MP literature, and what would I pay?
I'd guess 5k or so (380hp) because figure if you build one and use better aluminum heads and better rods you might spend $7,500 or so. ps so everyone doesn't kill me these are just approx. prices.
 
Thanks. Don't know yet what the HP rating is. I guess the low end is 300HP
 
Thanks. Don't know yet what the HP rating is. I guess the low end is 300HP
It's just a 5.9 magnum long block, 300 has stock cam and dual plane and 380 cam and single plane, i wouldn't pay any crazy amount for it.
 
Next step is to get the seller to contact me. I don't know yet
 
Next step is to get the seller to contact me. I don't know yet

So the pictures don’t show the intake?

The motors had all new parts. This is coming from ns1rm21 that guesses he sold about 200 small block crate during his time running Westoaks Mopar Performance.
 
So the pictures don’t show the intake?

The motors had all new parts. This is coming from ns1rm21 that guesses he sold about 200 small block crate during his time running Westoaks Mopar Performance.
Thanks, what are the options there? I mean between the 300hp version and the upper ones? Looks like an M1?

MPmagnum.jpg
 
Thanks, what are the options there? I mean between the 300hp version and the upper ones? Looks like an M1?

View attachment 1716044616

That’s a 300/320 horsepower motor. It’s got a dual plane intake, hydraulic roller cam, stamped steel rockers, 9:1 compression. Should run off 87 octane pump gas

The 380/390 and up horsepower magnums had single plane intakes.

Edit: looking at my 2002 and 2007 MP catalogs there was a bump in HP on these 300/320 magnum engines due to the "New Magnum R/T big valve heads" (2.02" intake)
 
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Del, you gonna put that on your trike?
 
I wouldn't pay anymore than a standard long block truck 5.9l with performance goodies on it.
 
What was the change that made it 320 vs the original 300?
 
That’s a 320 horsepower motor. It’s got a dual plane intake, hydraulic roller cam, stamped steel rockers, 9:1 compression. Should run off 87 octane pump gas

The 380 horsepower magnums had single plane intakes.
You know that from the intake? Thanks --- I respect your knowledge, generally. If so I think I'll pass For one thing the non LA intake drilled heads. Magnum heads or not, I'd like to retain LA intake compatibility.

Whoever I talked to on this (estate sale) is supposed to attempt to find more info. I pointed out that I could see a sticker on the head, and that the price may be "over" depending on what it actually 'is'
 
What was the change that made it 320 vs the original 300?

300 HP Commando LA motor: high swirl production heads (1.88 intake, .474-280-60 purple cam) .1993-1994 MP catalog and earlier P/N P4529783

300 HP Magnum motor: with production heads w/1.92 intake, .385/.401-250/264 cam. 1995 to at least 2002 MP catalog P/N P5249498

320 HP was Magnum motor: with R/T heads w/2.02 intake, .385/.401-250/264 cam. Sometime after 2002 to at least 2007 MP catalog P/N P5153476

Edit:
many changes in crate motors over
 
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You know that from the intake? Thanks --- I respect your knowledge, generally. If so I think I'll pass For one thing the non LA intake drilled heads. Magnum heads or not, I'd like to retain LA intake compatibility.

Whoever I talked to on this (estate sale) is supposed to attempt to find more info. I pointed out that I could see a sticker on the head, and that the price may be "over" depending on what it actually 'is'

Yes. Slam dunk.
That’s why @Bobzilla and @273 first asked about what intake was on it.

Street master makes an air gap copy magnum intake.

Mopar had a single plane M1 with Magnum bolt arrangement, but sorta hard to find used. But if you were using a single plane you’d be changing everything else in the motor to need it except the block, crank, and rods.
 
What was the change that made it 320 vs the original 300?
It's rated 300 hp but when they dyno it made 320 hp with headers, the 380 one makes over 400 hp on the dyno.
 
Just me, but the intake color seems off. Like it was painted later with a different paint and swapped on.

Might be that it is the higher HP crate motor with the dual plane swapped onto it.

But I’ve never messed with one so don’t know that it isn’t how they came originally.
 
Looks like there is a sticker just above the bellhousing bolt in that picture, too. Wonder if they could get you a close up of that, maybe it would have a part number on it.
 
man that would be perfect for our dart.

Many people that bought the 380 would have been happier with the 300/320. Both motors made a little more than that to comfortably advertise the HP rating.

Neat motors with reliable stock replacement roller lifters.

The 380 had a sorta choppy cam to get that HP with only 9:1 compression and low lift with stamped rockers. At some point the 380 magnums got R/T cast iron heads and possibly roller rockers.

And many 380hp crate buyers didn’t have the basic tuning skills and/or had expectations of new magnum truck starting up on a cold morning.
 
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I know three people that bought those back when Mopar was selling them... All three had issues, they all used oil, two spun bearings & one the lifters always rattled.. I'd build my own engine before buying one of those...
 
Just me, but the intake color seems off. Like it was painted later with a different paint and swapped on.

Might be that it is the higher HP crate motor with the dual plane swapped onto it.

But I’ve never messed with one so don’t know that it isn’t how they came originally.

Ns1rm21 texted me, “Engine is still in big blue bag, they used a big square tape/sticker over the distributor hole….everything looks original to me. “
 
You know that from the intake? Thanks --- I respect your knowledge, generally. If so I think I'll pass For one thing the non LA intake drilled heads. Magnum heads or not, I'd like to retain LA intake compatibility.

Whoever I talked to on this (estate sale) is supposed to attempt to find more info. I pointed out that I could see a sticker on the head, and that the price may be "over" depending on what it actually 'is'
Don’t pass because of intake bolt pattern. Make your decision based on the parts that are on there and what you want.

Even if it was perfect when packaged, it’s been sitting a long time. It should come apart for inspection. Could be some rust. They were coated with something like cosmoline, but sometimes rust forms in random areas. While apart you could drill the heads for LA intake pattern.
 
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