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Supercharging a 6.4

14K views 13 replies 9 participants last post by  turner56 
#1 ·
Has anyone done this to their 6.4? Any feedback would greatly be appreciated!
 
#3 · (Edited)
Just did a Kenne Bell recently.
There are a ton of threads on multiple forums on the subject.

The gist I would summarize as the following based on subjective experience.

Save your money.
I don’t say “don’t do it,” simply to understand that there are preliminary steps involved.
If you’re not going to stroke the motor, do a minimum of the pistons at the same time.
That’s also means head bolts, potentially labor, and new gaskets. Already looking at a few thousand right there. If you’re already in there, it’s a good time to do the rods.

And since you’re already there, lifters and pushrods should also be on the list, especially if you’re running MDS. You do NOT want to have a situation where you repeatedly go into boost with cylinders deactivated. It should be handled in the tune, but the MDS lifters Will become a failure point.

Consider doing the fuel system to make sure it’s good to 1000 crank hp. If you decide to go with e85 for any other reason later, it will support a greater load even if you never hit that number.
Consider which kit, and which injectors it comes with- it may be less expensive in the long haul to get a “tuner package” so you can specify which ones. Again, look for E85 compatibility.

Consider whether or not you plan on running the kit tune or something custom, as it may lock you into a specific aftermarket support system (diablo has problems reading hptuners modified PCMs now, apparently. Not sure if it’s specific to the Trinity 2 or not, but you need to do research or may get bit by this later.) This can all come back to haunt you later if you choose to do additional modification or tweaking. Make sure you know who did the tune, and have a roadmap to changing it if you need to. The cars and kits aren’t different, but gas quality, operating requirements, and environmental considerations are. The computer can adjust for all of this individually, and all of it together- to a point. It can’t adjust for Murphy or adding additional issues on top of everything that creates tolerance stacking

Consider adding a quality wideband AFR sensor, so you have something pertinent for tuning use in case something goes wrong, horribly wrong, or terribly right. Tuning is about good data. Garbage in, garbage out.

Finally, consider the use of methanol or water/methanol injection. This is not a substitute for doing any of the above, but can’t lower some of the risk of bad gas, bad moon alignment with mars, and all the other crap that can go wrong “just because.” It will keep things cooler and is an adjunctive hedge (NOT a primary) against knock.

All told, just doing all of the above well can run you 15-18k. Half-assing it and just slapping a blower on will run somewhere around 10k. After that, time starts on parts breaking. If you do the rest, the clock runs out on the engine slower, and you could expect many years of good service without issues with proper maintenance.

Which is good, because you’re going to want to save money for the inevitable drive shaft, axles, and transmission swaps that will be required after a certain point, roughly in that order.

Then you’re going to also want to redo the suspension, rims, and tires to put it all down.

At that point, you could have potentially spent upwards of 30k in parts to add on or swap in a scat pack or 392 that will be worth less than half the sticker price new after a few years.

It will be yours, and it’s will be a bit of a sleeper. If that’s what you want, great. However, don’t ever kid yourself that it’s a financially sound investment. If that’s a point of concern, stop before you start, enjoy the car for what it is for a while, and trade it in on a hellcat- much easier starting point to mod up to 800 hp with, and potentially less expensive, too.

Beware the hidden costs, and always plan for the extra 2k in parts and labor you didn’t predict.
Don’t expect miracles from adding 6-7 lbs of boost- fastest 1/4 I’ve been able to eck out on 6.5lbs is a new 11.66 on 305 drag radials. Novice driver, maybe track prep issues, still learning, etc. However, test times by experienced folks at that same power level are only doing about 11.55. Anyone else that claims faster with “stock with blower only @6 lbs” probably isn’t.

All in all, it’s your money and your choice. However, if I could do it again, I would have listened to my gut and just done a built 426 short block first beforehand, and worked up from there.

It’s easy, it’s fun, and completely doable- until something breaks, or until you want to crank up the fun. After that point, it’s best to have another vehicle and deep pockets because it’s going to be a hot minutes before you can drive it again.

Cheers,

Chuck

ETA: OP- specific to your car, it will already require a tune for the headers. If you already have an unlocked PCM and tune (assuming yes,) I’m guessing you already have a shop in mind or the ability to DIY. In that case, you probably have about half of it already figured out- just don’t forget about plugs, injectors, fuel system/BAP, and a wideband.

Lot’s of dudes popping pistons doing this (reportedly). Common denominators seem to be no w/m injection, not doing the fuel system, running it hot on back-to-back WOT runs without checking oil/coolant temps, and generally dumbassery. “I was only running 7 lbs. And a cam. And headers. And my tuner said it was all good!”

Okay stud- who did the tune, and did you log your runs? No chance you did a pulley swap for a few drags and didn’t say anything? What octane were you running, and who did the tune? Hmmm.

Getting everything to play nice together seems to be an issue you want someone with experience to tune. Running a little more octane than needed by a few points at the strip seems like a reasonable course of action. Not letting it heat soak repeatedly seems like common sense.

Checking logs for knock also seems like a pretty good idea. Wondering how many people actually did/do that.

There’s a number of people who did all that and still got unlucky. However, I would hazard a guess that it’s a much smaller number than those that didn’t.
I love driving this thing, but I treat it like I do a machine gun- take care of it, run it within the design tolerance, and get broken parts replaced before they break other parts... or other people. If possible, replace out of spec parts before catastrophic failure, and pay attention when it’s trying to tell me something. Don’t push to failure outside of a genuine emergency.

And remember that everything has a built in shelf life. The harder it runs, the more it’s gonna need some work done at some point.

Rant off, and good luck.
 
#7 ·
Don’t expect miracles from adding 6-7 lbs of boost- fastest 1/4 I’ve been able to eck out on 6.5lbs is a new 11.66 on 305 drag radials.
Holy Crap! I'm running 11.8's with a stock 392 with a tune and a drag radial. $10-15K for .2 and lots of chances for broken parts doesn't sound like such a good deal.

Thanks for sharing your knowledge and experience.
 
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#6 · (Edited)
Not that I need to keep running my big mouth, but...

More specifically, since you already have the cam as well (sorry I missed that before,) you’re probably going to want to do yet another cam swap for something more specific to a blower grind.

And this point, I’d almost recommend just buying another built shortblock, and either keeping the original for a future build or selling it to recoup. It’s YOUR car, and not my place to tell anybody how to live, but in case someone else is in the same boat, it’s another consideration.

Now having said all that...

Boost is f’in awesome, and that twin screw whine warms the happy places in my cold dark heart. It’s like so many more memes make sense now, and apparently it also makes certain drivers of other “sport cars” that shall not be mentioned reconsider running their mouths- they don’t know how much boost is going in, but they don’t seem to want to find out by looking foolish in the process.

Also, I forgot that I had a radio for about the first week.

Three fast ways to shut up a mustang-owning motor mouth. Get a blower, put a crowd in front of them, or ask them if they want to race from a dig. Two of those in combination is better, but I don’t recommend combining with the middle option, as it can get awkward.

I’m very much pro-FI. It’s just a deep rabbit hole to jump in.

But damn if it doesn't sound and feel good doing it.
Now I just need to figure out what I’m going to give up to afford going onto the next step. Fairly certain my retirement savings potential just went to hell, but I will not regret looking back as to why. Rather happy I did this than live like a pauper so I can be a raisin on a beach “someday.”

To each his/her own. But I have a shiny thing, and I like it. ��
 
#10 · (Edited)
maximum of 7 psi with a good, real fuel system, not a boost pump, tuning is critical,

at 7psi you will gain with a Magnuson 2300 approx 120/130 whps, add high quality long tubes and green catted high flow cats like Kooks and approx 580/590 whps which translate to approx 660/670 crank horsepower

stock 6.4L makes approx 420/430 wheel horsepower or 485 crank horsepower

in comparison a 5.7L makes approx 320/330 whps or 375 crank horsepower

if installed properly and tuned properly, will live for a very very long time

remember you dont have to have a supercharger to break components, or an engine.....if the driver is stupid enough or abusive enough you can break anything......

on a 5.7L at 8 psi with Kooks long tubes and green catted high flow cats, approx 505 whps or 575 crank horsepower

for comparison a Hellcat makes approx 630 whps and 707 crank horsepower

Luke

ps power output will be affected by temperatures, humidity etc
 
#12 ·
Are those 5.7 compatible? Any numbers from a setup with one?
 
#14 ·
Luke you keep giving me things to buy... what 5.7L springs do you recommend with the HC cam? When I get bored with my setup I'll probably put in a cam in this winter.
 
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