Vvt lock or not

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Edsrt

Edsrt

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Just finishing putting back together a 5.7 Hemi from a 2012 ram. Basically stock except for 392 cam and removed dod lifters and deleted solenoids. My question is is it necessary to lock the cam phaser if not using variable cam timing. It looks like there is a spring that keeps the phaser in position until acted opon by oil pressure. Since I haven't decided what system I will be using to run this engine. It would nice to have the option to use it or not without pulling the timing cover. Plus I be installing this engine in a 4spd Duster and was concerned about shift shock if not locked and solenoid not active. Any help or opinions appreciated
 
Its already been proven that the 6.4 cam in a 5.7 makes more power if you leave the full VVT cam timing curve in it. If you lock it out or use a limiter there is a substantial power lose. Just need a new tune that adjust the cam timing a few degrees to step up the low and mid range torque.
 
I just purchased a 5.7 crate engine for my 71 Charger and am considering putting in a 392 (6.4) cam. I have searched around and there are more questions than answers and i am hoping someone here might be of help.

1. Since I have an Eagle engine, I suspect I need a 392 cam for an eagle engine?
2. some say the valve springs need to be replaced yet some say you don't unless you are going to pull deep RPM
3. my engine is a non-MDS engine but does have VVT (as I think they all do). Do I need a non-MDS cam?

I appreciate any information/assistance on this issue
 
Okay, I will try and answer your questions in order. I have changed cams in my 5.7 Eagle 2012 R/T Classic 6 spd. twice now, the first time to the 392(6.4) non MDS cam and the second to a larger custom cam for more power. The 392 cam was the better all around cam, the custom cam was good for more power over 4000 rpm's with a little lose under.
1. If you have a non MDS 5.7 engine then you need the 392(6.4) non MDS cam part# 05037379BC
2. The valve springs NEED TO BE REPLACED, the 5.7 Eagle springs are good to about .550 lift the 392 cam(6.4) has .571 lift, can you say coil bind. The 392(6.4) springs will not work either on the 5.7 Eagle heads, Mopar Performance makes a performance valve spring kit for the Gen 4 VVT engines, the part# is P5160074 for up to .625 lift.
3. Yes, and as I stated in reply #3 above, do not lock out or use a limiter or you will lose power with this cam. It was engineered to give best performance with the full cam timing sweep. If you use the stock 5.7 Eagle car intake manifold this cam will pull hard to 6000 rpm's, put the 6.4 SRV (short runner valve) intake on it and hook up the short runner valve mode electronics and it will pull hard to 6400 to 6500 rpm's and make more low end torque in long runner mode, if you go this route contact me and I will tell you how to hook the valve up with and MSD 8969 RPM window switch. The 5.7 truck SRV intake will not fit on your 71 Charger, not enough hood clearance.
P.S. These 5.7 Eagle Hemi's love long tube headers. wakes them up from idle to max rpm's
 
This is awesome information and I greatly appreciate you taking time to type it. It is exactly what I am looking for. If this works out well, I might have put one into my 2010 Challenger RT 6spd.

At present I am planning on using the 5.7 intake but I will be running long tube headers.

I don't need big RPM, this is going to be a street car, so basically I am looking for low end performance. Not saying it will never go to 6K+ but it will be rare.
 
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19DART66 said:
Okay, I will try and answer your questions in order. I have changed cams in my 5.7 Eagle 2012 R/T Classic 6 spd. twice now, the first time to the 392(6.4) non MDS cam and the second to a larger custom cam for more power. The 392 cam was the better all around cam, the custom cam was good for more power over 4000 rpm's with a little lose under.
1. If you have a non MDS 5.7 engine then you need the 392(6.4) non MDS cam part# 05037379BC
2. The valve springs NEED TO BE REPLACED, the 5.7 Eagle springs are good to about .550 lift the 392 cam(6.4) has .571 lift, can you say coil bind. The 392(6.4) springs will not work either on the 5.7 Eagle heads, Mopar Performance makes a performance valve spring kit for the Gen 4 VVT engines, the part# is P5160074 for up to .625 lift.
3. Yes, and as I stated in reply #3 above, do not lock out or use a limiter or you will lose power with this cam. It was engineered to give best performance with the full cam timing sweep. If you use the stock 5.7 Eagle car intake manifold this cam will pull hard to 6000 rpm's, put the 6.4 SRV (short runner valve) intake on it and hook up the short runner valve mode electronics and it will pull hard to 6400 to 6500 rpm's and make more low end torque in long runner mode, if you go this route contact me and I will tell you how to hook the valve up with and MSD 8969 RPM window switch. The 5.7 truck SRV intake will not fit on your 71 Charger, not enough hood clearance.
P.S. These 5.7 Eagle Hemi's love long tube headers. wakes them up from idle to max rpm's
Click to expand...

So, I have purchased a 6.4 cam and the Mopar performance springs. I also discovered that Holley now has a VVT and a SRV controller harness that goes to their terminator X max harness system (which is what I want to use).

I have read on other forums about having to change the push rods? Is this something I need to look at?

I appreciate all the help
 
I have not changed the push rods in my 5.7 for ether cam change, my resigning for this is the stock factory valve springs for the 5.7 Eagle have over 400 pounds per inch of spring pressure. The stock 6.4 along with the Mopar performance and the PSI 1511ml springs that I used all have spring pressures in the 380 pounds per inch range. The 5.7 Eagle and 6.4 Apache both use the same part number push rods. I just figured if Chrysler made them strong enough for the 6.4 cam and 6200 rpm shift point of that engine they should be strong enough. But many tuners and mechanics think they are not, so that is up to you to make that decision. I put the 6.4 cam and valve springs in my Challenger at around 10,000 miles and the custom cam in at around 45,000 miles, the Challenger now has over 50,000 mile on it with the rev limiter set at 6800 rpms with no problems with the engine. Now that TR6060 6spd trans that a whole nother story, I would never buy a car with one of thoughs again worst shifting trans I ever owned. Fought Chrysler throughout the whole warrenty to replace it and just bought a low mileage one to replace it( not cheap), I am not going to wholed my breath over whether its better or not
 
Thanks for the response, it is very helpful. I bought this cam (and springs) for the new crate motor going into my 71 Charger but am seriously thinking about putting one into my 2010 Challenger as well.

I can't say anything negative about the trans in my Challenger, however to be honest I don't drive that car all that much, same with my 01 Viper which I think has the same trans (could be wrong)
 
70chall440 said:
Thanks for the response, it is very helpful. I bought this cam (and springs) for the new crate motor going into my 71 Charger but am seriously thinking about putting one into my 2010 Challenger as well.

I can't say anything negative about the trans in my Challenger, however to be honest I don't drive that car all that much, same with my 01 Viper which I think has the same trans (could be wrong)
Click to expand...
I found the 6 spd in the new Challengers really sloppy after about 25k miles. I don't own one but have driven a few of them. As for the Viper, it should have a T56 Magnum transmission.
 
My challenger has around 23K on it so I guess we will see, so far no complaints. I cannot say it is or ever has been super tight, but it is and always has been smooth. Conversely the Viper is very precise. You can definitely mistake gears in the Challenger but no so much with the Viper.
 
Can anyone help with the part # for the 6.4 VVt cam Thanks.............Pete
 
Pete - all of the modern hemi's are VVT, therefore all of the stock cams would be as well. The question is whether you need a MDS capable cam or not. Either way, here are the numbers I have; (please confirm type/usage before purchasing)

18-20 6.4 Hemi w/MDS 5037379BC
21 up 6.4 Hemi w/MDS 5038419AB
18-20 6.4 Hemi w/o MDS 05037379BC

Valve Springs P5160074
 
Got it..... the engine is out of a 2014 R/t 5.7 don't care for the MDS but would like to keep the VVT, which cam do you think would be the best? PO#05037379BC sound good.....again thank you for the help..........PETE
 
Dodge74 said:
Got it..... the engine is out of a 2014 R/t 5.7 don't care for the MDS but would like to keep the VVT, which cam do you think would be the best? PO#05037379BC sound good.....again thank you for the help..........PETE
Click to expand...

If the engine was out of a AT car it has MDS, if it is out of a stick car it doesn't have MDS. That said, if you have a MDS engine then you need a MDS delete system (which they sell).

I am using 05037379BC for my crate engine bc it is a non MDS engine. You will also need the springs.
 
Edsrt said:
Just finishing putting back together a 5.7 Hemi from a 2012 ram. Basically stock except for 392 cam and removed dod lifters and deleted solenoids. My question is is it necessary to lock the cam phaser if not using variable cam timing. It looks like there is a spring that keeps the phaser in position until acted opon by oil pressure. Since I haven't decided what system I will be using to run this engine. It would nice to have the option to use it or not without pulling the timing cover. Plus I be installing this engine in a 4spd Duster and was concerned about shift shock if not locked and solenoid not active. Any help or opinions appreciated
Click to expand...
Well after not working and then illness finally got the Hemi running in my Duster. Spending more money than I wanted to for Intake manifold,fuel system, hydraulic clutch, dash and engine wiring harness plus megasquirt Hemi gold box. Also waiting for the Mopar performance valve springs that I ordered back in March. Finally started it up this week after some finagling with the ECU setup she fired up ,idled with good oil pressure and revs without hesitation. Still some tuning to do and need to finish the exhaust system,brake system and the rest of the might as well items such as rebuild front suspension, replace carpet and batteries. Still have not turned on vvt yet properly will wait until car is back on the Road . Can't wait.

20210921_142634.jpg
 
70chall440 said:
18-20 6.4 Hemi w/o MDS 05037379BC

Valve Springs P5160074
Click to expand...

Edsrt, nice job on the install! You are so close to driving it!

So, when going to the 6.4 cam in a 5.7; it sounds like the 5.7 valve retainers can be reused?

I'm using a 2014 Challenger R/T donor. Going to keep the VVT but not the MDS.

20210930_121149~2.jpg
 
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Hmmm. I just checked P5160074 springs and they have been discontinued. Looks like they were a complete set of 16.
I'll have to check if they are available individually.
 
KosmicKuda said:
Hmmm. I just checked P5160074 springs and they have been discontinued. Looks like they were a complete set of 16.
I'll have to check if they are available individually.
Click to expand...
I ordered these springs individually though the dealership I work for and they never canceled the order just kept postponing it. Plus I think the price on the kit was about 200 dollars and individually was just under 70 go figure
 
Just want to make sure, will the P5160074 fit the 2012 truck engines? I'm new to the Hemi and have a truck with the donor 5.7 and after reading everything it sounds like I need the springs and the 392 cam. It's going into a 71 Demon. I'm starting to collect parts...and they aren't cheap. Also, what is MDS? It sounds like the truck engines with an automatic transmission will have it. Can it be deleted and use a non MDS cam? I'm only using the long block out of the truck. I will be going with a carb style intake and a 4bbl Sniper.
 
MDS is Multi Displacement System. It disables four cylinders for an Economy Mode. I.E., better fuel mileage. When you delete it, it's all or nothing. Meaning you have to replace the MDS specific lifters and delete the MDS solenoids. There are plugs to replace the solenoids. Why aren't you using the heads off of that 2012? They are decent flowing heads. You should use 6.4 springs with the 6.4 cam.
 
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