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Discussion Starter #1
I have pretty much done all the starter bolt on mods i can think of off the top of my head. I posted a little while back but heres what i got...

2012 6.4L srt8

-cold air intake
-long tube headers
-midpipes
-cat back exhaust
-new camshaft (with pushrods and valvesprings )
- torque converter
-diablo trinity tuner/programmer
-nitto 275's on the back

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Okay so now the only thing i could of is
-new heads (apache?)
-forged shortblock (stay with a 392 or go bigger? Theres no replacement for displacement right? give me feedback here. Idk if a new forged 6.4 would be as good as it gets or a 426 or a 6.4 and have it bored and stroked or what)
-forged pistons
-supercharger (double screw. I like supers for v8s)
-water injector?
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Okay so comment on everything above if you would like. And throw as many ideas with rough pricing ideas on everything else. Idc what it is as long as it makes me car go vroom faster than it would without it :D

maybe cooling strips on certain components (the aluminum foil looking stuff) idk. List EVERYTHING. Specifically things that dont involve tearing my block apart again. I wish i would have gotten the heads at the same time as the cam....
 

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Discussion Starter #2
Also i forgot, i read on another post that a limited slip differential would be beneficial but it didnt say what model 300 it was. What about an egr block? Or anything that has to do with the gear ratios? Im okay with losing some power at the top end if i gain some at the lower end. Im looking for speed within reason. A.k.a im not tearing apart my seats and shit haha
 

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Ok... so you are really at the point I was at with my gen 1 awhile back.

Heads are never a bad thing, even the gen 2 392 heads have their restriction points. Getting some apache heads will really help knit it all together as at the moment the heads will be about the largest choke point for your list of mods. An engine is a big air pump, more volume in equals more volume out, you've given the engine the desire for more air with the cam, given it a way to exit and even a slightly better way to feed it in, the heads are going to let it circulate between combustion and exhaust much easier and allow more volume at the same time... Can't hurt for sure!

From there imo your looking at nitrous or boost... nitrous is truly awesome and addictive, but, it's a pita unless you have a refill station in your back yard and in the long run it can get costly quick if your spraying everywhere you go like me.... so I ditched it and I bet you would too in time!

If your going supercharger then you have the centrifugal vs roots style blower battle next, looks like you decided on a roots style twin screw blower, I personally prefer building my motor for torque and spinning a centri charger for help down low and mad power up top. But that's just me...

If you have a 392, they have a history of popping under boost. Many run blowers for years with no issues, some tuned by the best tuners in the US, pop within a few K with very little abuse. There is no common trend with the 392, some ringlands just let go no matter how clean the tune is. Imo if your going to boost and have low miles, get some drop in stock bore forged pistons to be safe. Do them with the heads as your half way there and then boost. Keep the levels around 10psi or less on the rest of the bottom end and go rip up the streets...

If you want more then I'd say your into lifting the motor and boring the block to give it some added displacement and stroke. If so forge it all, crank boost over 15psi and go run full trim in the 9's! Lol (well...with a new transmission and diff!)

Gears are a fun addition as is a higher stall torque converter, they are both torque multipliers and with good traction make the car feel 1000lbs lighter... might want to look that direction as well at some point...
 

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If you go into building an engine with more torques and horsepowers you'll want to consider upgrading your transmission.

Another fun torque multiplier is a change in rear diff gearsets. You have an LSD but it's probably 3.06:1 and a 3.55:1 or even a 3.73:1 gear set will significantly improve off the line speed and lower your 0 - 60 ft times. If you run your car on the freeway or want to take road trips, the 3.73:1 set may be a bit too tall. The 3.55:1 is a great all around gear set to use for street, strip and roadway.

Bore, stroke, forge and add a supercharger! New pistons with a different ring configuration will remove the ring land issue. I've seen a few stock pistons with that failure and aftermarket units move it down a bit from the top of the piston to avoid that failure. Lots to consider here but I got three numbers for ya... 4 2 6 ...just sayin'... :D

Have you done anything at all with the suspension yet?
 

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Discussion Starter #5
No i havent done anything with suspension yet. If i supercharge it, would i need a stronger driveshaft?

So what im getting from you guys is
-pistons
-heads
-shortblock
-boost
-gear ratios

Now with the shortblock. Obviously i will need a forged one to handle higher pressure. What short block would you recommend?
 

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Discussion Starter #6
Also, once i do supercharge, a new transmission is going to be needed right? to handle the added power? And will it improve performace anyway? What tranny should i get? A custom made one?
 

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Your driveshaft will be fine.

Use your block for the build. You don't need to get a new one unless you want to drive the car while an engine is being built, then just swap engines and sell off the stocker later.

Your existing transmission can be upgraded to handle the additional power. Paramount or SHR can do the job for around $4k total. Or you can buy one from them and do the core swap with them for your old transmission.
 
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