380hp crate engine specs

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maca

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Hey guys
Does anyone know where I can find the specs on an engine I am looking at?
I am after head flow, cam specs and comp ratio etc and new price
The part number is 1-P4876906
 
To the best of my knowledge it was discontinued several years ago. It is a factory 5.9 with the exception of the pistons(flat top), cam .513" but lots of duration if I remember correctly. valve springs and front cover. The comp was 9.5-9.7. Head flow for 155 cc runners should be in the 200 ball park. this is off top of my head so excuse slight errors. Price is irrelevant if used as a used 5.9 short block is $200-$400,new heads, cam and front cover/car pan can all be had for $2000 ish. I think the 380 was $4500 ish but they were considered way overpriced at the time.
 
The Magnum 380 crate motor head is a swirl port design that has smaller combustion chambers and a higher compression ratio (nominal 9.0:1). Different intake and exhaust port sizing flows more air without modifications to the cylinder heads. Breathing is enhanced with 1.925" intake valves and 1.625" exhaust valves. Overall package of smaller valves and better ports flow more air. Next, we slide in our .501" / .513" lift, 288/292 degree duration hydraulic roller camshaft, add a 4BBL carbureted M1® single plane intake manifold (with bosses over each runner for future MPI). We add special valve springs and a double roller timing chain as well as an MPP electronic distributor. The distinctive Mopar cast valve covers with 10 screws are added to the package, with an oil pan (center sump) similar to the Commando engines. It is recommended you add your own 750 cfm Holley carburetor and headers to complete the package. Dyno testing with a 750 cfm carburetor and 17/8" headers show horsepower output to be 380+ at 5300 RPM. Torque output is 410+ lb/ft at 4400 RPM, with over 350 lb/ft available from 2000 to 5700 RPM.

I think the original sale prices were around $3500.

Summit/Jegs sells them for $10K. Ridiculous if you as ask me
 
The Magnum 380 crate motor head is a swirl port design that has smaller combustion chambers and a higher compression ratio (nominal 9.0:1). Different intake and exhaust port sizing flows more air without modifications to the cylinder heads. Breathing is enhanced with 1.925" intake valves and 1.625" exhaust valves. Overall package of smaller valves and better ports flow more air. Next, we slide in our .501" / .513" lift, 288/292 degree duration hydraulic roller camshaft, add a 4BBL carbureted M1® single plane intake manifold (with bosses over each runner for future MPI). We add special valve springs and a double roller timing chain as well as an MPP electronic distributor. The distinctive Mopar cast valve covers with 10 screws are added to the package, with an oil pan (center sump) similar to the Commando engines. It is recommended you add your own 750 cfm Holley carburetor and headers to complete the package. Dyno testing with a 750 cfm carburetor and 17/8" headers show horsepower output to be 380+ at 5300 RPM. Torque output is 410+ lb/ft at 4400 RPM, with over 350 lb/ft available from 2000 to 5700 RPM.

I think the original sale prices were around $3500.

Summit/Jegs sells them for $10K. Ridiculous if you as ask me

The Magnum factory heads are closed chamber high swirl 9.1 comp. The 380 hp engine uses the EXACT same heads that came on a 5.2 Durango. The 5.9 heads from 93-2000 had a 1.88 intake with the exception of the RT Magnum which carried the 1.92 intake of the 5.2.

MP was charging $4500-$5000 for 380 HP, the 300 HP was $3500-$4000.

In the 380 HP, you get cam, springs, timing set plus all the **** they bolted to long block.
 
Thanks
So where do they sell them now or are they obsolete.
Not interested in the $10,000 engine. Lol
 
That part no. is just for a short block, but here are the Specs right out of the Mopar Catalogue.

Part Number*P4876906
Block Magnum 360
Deck Height 9.580"
Crankshaft 3.58 Cast
Rods Forged
Length6.123"
Pistons Hypereutectic
Coated Skirt
Comp Height1.58"
Bore Size 4.020"
Rings 5/64"
Camshaft Hydraulic Roller
Timing Chain Double-roller w/sprockets
Head Oiling Pushrod
Lift @ Valve 0.501"/0.513"
Duration 288/292
Fuel System Carb. w/Mech Fuel Pump
 
Thanks
So where do they sell them now or are they obsolete.
Not interested in the $10,000 engine. Lol

Some of the big guys sell a "copy" built by any number of "bulk builders" but my guys havent had them for a few years. They ran out of new blocks(presumably) because they started using and building remans for the last couple of years. They came with oversize pistons, not sure about crank or heads but saw a few 4.030 or 4.040 ones. Like I mentioned, a used factory short block with no issues, then aforementioned parts will make an easy 400HP.
 
That part no. is just for a short block, but here are the Specs right out of the Mopar Catalogue.

Part Number*P4876906
Block Magnum 360
Deck Height 9.580"
Crankshaft 3.58 Cast
Rods Forged
Length6.123"
Pistons Hypereutectic
Coated Skirt
Comp Height1.58"
Bore Size 4.020"
Rings 5/64"
Camshaft Hydraulic Roller
Timing Chain Double-roller w/sprockets
Head Oiling Pushrod
Lift @ Valve 0.501"/0.513"
Duration 288/292
Fuel System Carb. w/Mech Fuel Pump

Thanks Keith!
These are updated specs are for the later version with used block, note bore size 4.020"
 
Thanks guys
I was asking as I found a used one for sale with 2500 miles on it for $3500
I think I read somewhere that the comp for them was 9.6
It's getting up a bit high I think as I wanted it around low 9s
I must admit it surprised me a bit. My smaller cam 360hp engine ran really well at idle with a small lope.
This engine is way way more lopey but supposedly only 20hp more power.
This is my cam. Smaller
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=661&sb=0
 
That's a nice grind,Maca.The bigger cam bleeds off cylinder pressures,off the higher compression setup. If It were me: ported E.Q. heads,find a medium cam .(220-224 @ .050"intake ,228-234@ .050" duration,on a 110-112 lobe seperation depending on gear/converter(?),& tire diameter. Too far off the combo you know,will cost you money,you don't need to spend.
 
Thanks
There are guys getting around 400hp with that cam and better than stock heads. Idles nice too. Gave me 270 rwhp. Here it is. Will be eventually adding a vortech down the track.
[ame]https://m.youtube.com/watch?v=IDlrVyKz2pM[/ame]
Those cams you suggested what hp do you think I would end up with as I already have this cam sitting in the shed
 
Greg I had a 318 with home ported EQ mag heads, 222/228 @ .050 hughes hyd roller with 9.5 comp. It made 300 rwhp through a 904 auto and a BW diff. Would have been better with comp around 10 as the cam kills a bit down low. The Eq's will flow a bit more than stock mag heads
 
Thanks guys
I was asking as I found a used one for sale with 2500 miles on it for $3500
I think I read somewhere that the comp for them was 9.6
It's getting up a bit high I think as I wanted it around low 9s
I must admit it surprised me a bit. My smaller cam 360hp engine ran really well at idle with a small lope.
This engine is way way more lopey but supposedly only 20hp more power.
This is my cam. Smaller
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=661&sb=0

I'm confused. Do you have a Magnum based 360 already?

My observations/opinions: I've worked on a couple of cars with the Mopar 380hp crate. Cam too big, M1 single plane too big, compression too low (for the aforementioned) NO low speed/part throttle torque. Avoid if you don't have a light car w/deep gears.

I built this engine to emulate a 380 hp crate with a more torque oriented goal. http://www.forabodiesonly.com/mopar/showthread.php?t=266140

Current owner but it in a 3400+lb Mirada and he cannot believe how fast on the street it is. He says it will take his fathers 2010 Challenger RT with a few mods and his brothers '69 RoadRunner 440/6 with cam and headers. Torque below the peak is what rules here. J.Rob
 
That's a nice grind,Maca.The bigger cam bleeds off cylinder pressures,off the higher compression setup. If It were me: ported E.Q. heads,find a medium cam .(220-224 @ .050"intake ,228-234@ .050" duration,on a 110-112 lobe seperation depending on gear/converter(?),& tire diameter. Too far off the combo you know,will cost you money,you don't need to spend.

Everything here is spot on. J.Rob
 
Thanks Keith!
These are updated specs are for the later version with used block, note bore size 4.020"

Your right about the bore size, a friend bought the full 380hp motor and it was noted that his motor was 4.040, he also had the r/t heads with the 1.925 intake valves.
 
I'm confused. Do you have a Magnum based 360 already?

My observations/opinions: I've worked on a couple of cars with the Mopar 380hp crate. Cam too big, M1 single plane too big, compression too low (for the aforementioned) NO low speed/part throttle torque. Avoid if you don't have a light car w/deep gears.

I built this engine to emulate a 380 hp crate with a more torque oriented goal. 360 TrueStreet Magnum Build

Current owner but it in a 3400+lb Mirada and he cannot believe how fast on the street it is. He says it will take his fathers 2010 Challenger RT with a few mods and his brothers '69 RoadRunner 440/6 with cam and headers. Torque below the peak is what rules here. J.Rob
Not to bring a thread back from the dead, but what did you use for valve springs in that motor?
 
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