I am looking to build my 2020, Scat Pack / 392, automatic to 500 to 575 WHP probably Natural Aspiration. I know I don't have to forge the rotating assembly if I stay NA but I will never feel comfortable unless I do that. I for sure want to eliminate the MDS and put in new valve train. I would consider leaving as 392 or stroking it. I live in Colorado but I am willing to drive to either coast. and leave it for weeks. I park the car fall to spring to avoid salt. Has anyone had experience with EFI Specialties Fredricksburg, VA? I am open to advice. . Thank you.
Recommend 392 Build
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Shemi
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Wow, that is very good hp for a NA build! The torque could be higher, but then again its hard to get traction all the time with a stock motor. I wonder what that kind of build would cost?
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Give Glenn a call at RPM in Littleton. He’s a true Mopar whisperer. He did my 426 stroker and we got 540 to the wheels N/A on his Mustang dyno. Currently back in the shop for few new performance tweaks and Redeye half shafts. Experimenting with intakes now. 
2 year/24K mile warranty on anything he touches.
www.rpmdenver.net
2 year/24K mile warranty on anything he touches.
RPM - Rains Precision Motorsports | speed shop denver | 5241 South Rio Grande Street, Littleton, CO, United States
Denver's Best Full-Service Auto Shop RPM Denver. General Maintenance and Repair, AWD Tuning, Full Builds and All Work Guaranteed
www.rpmdenver.net
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HP 70 trans. denotes ability to take approx. 700 Nm of torque. That would equate to around 516 ft. lbs. I haven’t had any issues with my N/A build for over 30K miles. I think the HP70 is pretty stout as long as not launched with boost and drag radials. I let the rear tires spin for a fusible link.
Do you have any overlays of the old intake vs the sheet metal one? The old intake was a ported 6.1?
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I have the 6.4 intake. Kind of ported but mostly cleaned up for the casting flash areas.
I can vouch for DTP Racing in Chesapeake, Va. They installed my cam and headers and Brent completed the Dyno tune. I am very satisfied.
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im at 485 ishhh RWHP and will put 92mm throttle body this spring (not a lot of hp gain but better throttle response) could go a bit more aggressive with the tune and gain a little more hp but id rather go conservative and keep it reliable and drivable
Comp cam HTR stage 2, cam phaser, PSI springs, Manley titanium retainers, Manley shims, iridium sparkplugs, CAI, Kooks LTH, mids and high flow cats,91 octane tune
Will tweak the tune after the throttle body install and give some more feedback , Facebook
Comp cam HTR stage 2, cam phaser, PSI springs, Manley titanium retainers, Manley shims, iridium sparkplugs, CAI, Kooks LTH, mids and high flow cats,91 octane tune
Will tweak the tune after the throttle body install and give some more feedback , Facebook
Thanks everytone for your input. I needed a dose of reality related to the cost of doing what I originally stated. I think Medsport and Mango 392 are suggesting more realistic goals that achieve around 485 whp. Decent cam, headers, throttle body and tune. I will be happy with that. I have seen several MMX 392 builds on youtube putting out about 500 whp with the same set up and adding ported heads. Do ported heads add 15 to 20 HP?
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I think you would still be looking at about 15k in costs, and unless you have a great tuner, possible driveabliity issues. Are you sure you don't want to just trade for a Hellcat? With the unreal prices on low mile used cars, It shouldn't cost you too much.
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That's not bad at all.
My experience in driving through various areas of Colorado (and other western states at some altitude) the "way to go" is a turbo charged or supercharged car.
I'd leave the pistons, cam, ported heads, etc., on the parts shelf and install a good supercharger kit (a Procharger maybe) or with that new of a car trade it in for a factory supercharged car like of course the Hellcat.
Here is a pic of a new Charger (on a dealer's showroom floor) with a dealer installed Procharger.
Multiple very knowledgeable people who build and race Hemis (performance shop types), and probably many members of this site, say in regards installing a procharger or turbos to an otherwise stock 392 that "...it's not a matter of if, but rather of when..." pertaining to problems arising from blowing up stock pistons, crank, etc.
Buyer Beware.
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agreed. Now with a built rotating assy, all bets are off
Everybody wants to build an NA stroker 392 until the reality of the build cost settles in. I get the "built not bought" argument, but if you're paying someone else to build it, it's still just bought. Thus, at the end of the day, a person could easily spend 20k+ on an NA build and net 150hp less than a Hellcat for about the same price. Given that these builds take shops months to complete, you can even order a new Hellcat, literally with your name on the car from the factory, with a warranty, that comes with more horsepower and you'd receive it quicker.
Yes, yes, it isn't an NA car. It's a better car. It has better running gear, drivetrain, more stout internals... and I could go on. What's better is that you can get a used Hellcat with under 20k miles on it for low 60s. If you want to be built not bought, pulley it and make 800whp for $3,200.
At the end of the day, it's your decision. The cost to do this build is going to be a real eye opener, considering the ludicrous cost and relatively mild expected results.
The only reason to get said headers is if you're looking for sound production. If the engine's out of the car, then the header install is easy. Go for it. But kindly don't factor in any HP gain with the headers, because there won't be any.
Yes, yes, it isn't an NA car. It's a better car. It has better running gear, drivetrain, more stout internals... and I could go on. What's better is that you can get a used Hellcat with under 20k miles on it for low 60s. If you want to be built not bought, pulley it and make 800whp for $3,200.
At the end of the day, it's your decision. The cost to do this build is going to be a real eye opener, considering the ludicrous cost and relatively mild expected results.
Headers do -nothing- on the Hemi engines. From the 5.7 to the 6.2, headers do -nothing.- Anyone who says otherwise is just trying to sell you something. There's several 6.2s in the low 8s and they run stock exhausts (complete with stock cats for the new smog laws). So, if you're budget conscious, you don't need to spend $3,000 on headers+install because they aren't going to add anything more than 1-2hp, if that.
The only reason to get said headers is if you're looking for sound production. If the engine's out of the car, then the header install is easy. Go for it. But kindly don't factor in any HP gain with the headers, because there won't be any.
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Lots of Cats out there. Not many 426’s. It’s all about wanting something unique. I’m at around 633hp N/A crank (on pump gas) with my stroker so worth the $20K to me. Anyone can make HP with boost 😁
The above has applied to vehicles since turbos were available. It is true, as far as it goes.
But it is also true when adding a bigger cam or other engine mods to increase power.
In the case of adding a turbo (or turbos) or a supercharger limiting the amount of boost to -- a number tossed around by laymen and experts -- 6psi or less results in a reasonably reliable engine.
But some few have gone above 6psi and the engine appeared to have not suffered any. Personally I wouldn't count on this but it happens.
The flip side is even a non boosted 392CID engine can suffer internal parts failure.
In any case usage plays a role. Take a stock engine and thrash it and then don't be surprised when something breaks.
And of course this is true of a boosted engine. Run the engine with stock internals to the point it is being subjected to max boost for prolonged periods and it would be a surprise if it held together.
One boosts the engine and takes his chances. But this also is the case if he chooses to "forge" the engine prior to modifying it for more HP either by a cam, intake, exhaust, etc., or by some form of turbo charging/supercharging.
A good supercharger kit coupled with proper installation and a good tune to go with it, ensuring the cooling system is up to the job, probably installing a good oil cooler and paying attention to fuel octane and quality and keeping the engine in good tune goes along way to helping the engine stay intact and deliver a long a trouble free service life.
A hot rodded engine, hot rodded by any means, needs extra special care and attention and more frequent maintenance.
Too often I dare say once the turbos or supercharger or cam etc. is installed and the wrenches put away the engine receives less attention than it should.
Anyone can make power with an NA build as well. Neither forced induction nor NA builds are particularly complicated. The reason why many of us go FI is because it's more economical and arguably more durable to do so.
For example, using a stock 392 as a starting point, I could get your mid 600s to the crank, but at the wheel, on a $6,200 ProCharger install with nothing more than drop in pistons. The ProCharger install is a 1-man easy job that takes 5-6 hours. 4 hours with 2 people. With the pistons, there is little risk to the engine. I've done quite a few of these builds and it's common to start work at 8-9am and be done with customer pickup ready by 1-2pm, same day. That includes installing the unlocked PCM and dyno tuning it. The best part is, the ProCharger system is modular, so if you want more power out of it, all you have to do is take a half hour and remove the head unit and replace the P1SC or P1X with a D-trim unit. The D trim will add another 100whp, give or take.
To compare, you're talking $20,000 and months worth of waiting to get an NA build complete that will run somewhere in the 580whp range. Or, someone can spend under $8,000 for a ProCharger setup and not miss a single day on the road, and be doing so between 650-800whp depending on which head unit they went with. Granted, if someone wants a D1X head unit on their SP, they're going to need some costly trans work and a driveshaft too.
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Foolish to recreate the wheel at great risk and expense. Stick with the way these engines were designed. There's loads of threads of blown engines or endless problems with mods.
Live with what you've got or just sell/trade for an upgrade.
Live with what you've got or just sell/trade for an upgrade.
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