VCT with stiff springs and High volume/pressure oil pump

[Graham3913]

Been searching for an answer for a while. Does anyone know if you can use VCT limiters with springs around 300lbs/in if you have a High volume/pressure oil pump?

I know the vct wont work with those springs with the stock pump, thought they might if you upped the oil pressure though.

 

[RED09GT]

There are threads here with datalogs but I have no idea whether anyone has specifically used a high volume oil pump.
With how long these engines have been out, I would conclude that if the answer was that simple, it wouldn't be hard to get confirmation that it works.

Short answer is that it probably won't be enough to overcome the mechanical limitations but your results may vary.

 

[07 Boss]

Assuming you're going with a big cam if you need stiff springs, so why would you not lock out the VCT anyways.?

 

[Graham3913]

The cams are comp cams 127500.

I've read from livernois i believe that most of the gains are between 8-14 degrees, the limiters go to 20. I would just like to keep the gain in torque down low and up top if at all possible. I'm assuming that there are still some gains to be had even with the big cams.

 

[retfr8flyr]

I run a high volume oil pump, Livernois springs, Livernois limiters and custom grind Comp cams with the same lift as the 127500 cams. I have run this combination for several years now with no problems. If you go with higher tension springs than the Livernois, I would recommend going with lockouts.

I ran lockouts in a previous engine setup and I like like the limiters better, for street driving.

 

[Graham3913]

What are the livernois springs part numbers?

The springs im planning on using are 24 of the tfs-15411. They're 308 lbs/in.

 

[07 Boss]

The cams are comp cams 127500.

I've read from livernois i believe that most of the gains are between 8-14 degrees, the limiters go to 20. I would just like to keep the gain in torque down low and up top if at all possible. I'm assuming that there are still some gains to be had even with the big cams.

Running longer duration and higher lift with VCT, don't you run into clearance issues with the pistons?

 

[Badd GT]

I've run Livernois springs for years with 127500 cams and Livernois 20 degree limiters with no problems. Spring installed load is 105 and open load is 270. These have worked fine the last 18 months after adding a supercharger as well.

 

[RED09GT]

Running longer duration and higher lift with VCT, don't you run into clearance issues with the pistons?

This is why the limiters are necessary, you could theoretically adjust the tune to limit the retard but the mechanical force from the valve springs can overcome the phaser, the limiter stops that from physically happening.


Are you planning on running boost with the 127500's? Have you bought the springs already?

 

[BruceH]

Been searching for an answer for a while. Does anyone know if you can use VCT limiters with springs around 300lbs/in if you have a High volume/pressure oil pump?

I know the vct wont work with those springs with the stock pump, thought they might if you upped the oil pressure though.

It would depend on your clearances and oil viscosity. All you can do is try it and see if it works.

Assuming you're going with a big cam if you need stiff springs, so why would you not lock out the VCT anyways.?

Best performance with 127500 cams is going to come with the 102 icl for anything below a certain rpm (depends on the setup and will take data logging and other testing to determine) and roughly 8 to 10 degrees of retard in the higher rpms. Once again it depends on the setup and tuner.

 

[Graham3913]

I have not bought the springs already, but i do have the cams, 1mm oversize valves, single groove keepers, retainers, .020 over probe pristons, and a kellogg crank dad is gonna offset grind for me. I believe these and possibly the comp cams springs are the only ones that will work because of installed spring height issues. Many springs are around 1.67ish installed height, I think i'm only going to be around 1.64. The 1.67 springs installed at 1.64 wont work with the .555 lift cam, they'll be too close to coil bind.

 

[RocketcarX]

It's my understanding the 3v has a high volume/high pressure pump from the factory, is there a pump that takes that even further?
I learned about this building a 4 valve conversion, there are three pumps from what I understand

2 valve = standard pressure and standard volume
4 valve = high pressure and standard volume
3 valve = high volume and high pressure

The first time I did a 4 valve swap I didn't know and just used a new stock GT 2 valve pump, it couldn't keep up with the 4 valve heads and caused the valve train to chatter so if definitely affects the way the top end pumps up.

 

[Graham3913]

Looking at the website in the links below, the descriptions say that both of them would be higher pressure/volume than the stock 4.6 3v.


http://www.modmaxracing.com/product-p/melm360.htm

http://www.modmaxracing.com/product-p/mel10340.htm

 

[JeremyH]

Looking at the website in the links below, the descriptions say that both of them would be higher pressure/volume than the stock 4.6 3v.


http://www.modmaxracing.com/product-p/melm360.htm

http://www.modmaxracing.com/product-p/mel10340.htm

As mentioned the oem 3v/gt500 pumps are already high volume the melling pumps use the same gear size so there is no additional volume to be had. There is no difference in pump housing or volume between the two as well (3v/gt500). Gerotor gears are positive displacement so you would have to change the gear size to effect output volume (either diameter or thickness). There are just different pressure relief spring between the 4.6 gt and 5.4 gt500 version. I have been running the gt500 spring version for 6 years with comp limiters and springs.


"This new pump from Melling SELECT fits all 4.6 and 5.4 3V SOHC and 4V DOHC engines. This pump is for HIGH volume applications. It comes standard with a high pressure spring, but includes an optional lower pressure spring."

That spring is the only difference designating as one or the other. Guys have had success sticking with the oem 3v spring and gt500 spring.

 

[drive_55_not]

Looking at the website in the links below, the descriptions say that both of them would be higher pressure/volume than the stock 4.6 3v.


http://www.modmaxracing.com/product-p/melm360.htm

http://www.modmaxracing.com/product-p/mel10340.htm

The oil pump for the GT500 uses a longer spring and when used on the 3v you'll have higher oil pressure, I ran the FRPP 2013 pump [M-6600-F46 - $90] and had 70psi under normal cruising and 100+ WOT. IMVHO that's too much ..

One thing that hasn't been mentioned is with big cams and heavy springs you're going to beat the phasers to death. I had 2 fail using limiters and after the 2nd one, I locked the cams.


.

 

[Graham3913]

Well it seems like a few people are running the limiters with cams and stiffer springs, so i might give it a shot. I guess it'll depend if i still have enough valve clearance at the max 20 degree range. If not, i think id rather run the lockouts.

You guys think i would have piston-to-valve clearance problems with the pistons in the link if we had zero deck clearance?

http://www.coasthigh.com/Ford-4-6L-3V-5-0cc-Dish-Top-SRS-Pistons-p/14759.htm

Planning on running those with eagle 5.85in rods, and offset grinding the kellogg crank to the honda journals and stroking it to however far it'll go without running into clearance issues.

 

[01yellerCobra]

It sounds like you're planning on running a stroker set up. The crank in my 323 is offset ground the same way. You'll need a piston for that set up. You can't run a piston made for the 5.93" rod.

 

[Graham3913]

I should be able to run the pistons i have with an offset ground crank to 3.74" unless i'm missing something. That would give me 2 thousandths in the hole deck clearance, as long as piston to valve is ok.

Deck height 8.937
Stroke 3.74
rod length 5.85
pin height 1.215

The piston doesn't know what rod is attached to it, as long as the deck height/ptv clearance is fine, which we can adjust by changing the stroke to what we need.

Hopefully 11:1+ compression on E85

 

[01yellerCobra]

I should be able to run the pistons i have with an offset ground crank to 3.74" unless i'm missing something. That would give me 2 thousandths in the hole deck clearance, as long as piston to valve is ok.

Deck height 8.937
Stroke 3.74
rod length 5.85
pin height 1.215

The piston doesn't know what rod is attached to it, as long as the deck height/ptv clearance is fine, which we can adjust by changing the stroke to what we need.

Hopefully 11:1+ compression on E85

The issue you run into is on the other end. Stroker pistons are little shorter to clear the crank counter weights. The crank in my engine is a 3.75" with 5.85" rods. I'm aware the piston doesn't know what rod is connected to it. I was running Eagle rods for a Chevy smallblock in mine.

 

[Graham3913]

Ah I didn't think of that. Thanks for the heads up.

Dad said we could grind the crank counterweights and tig weld some heavy metal in if we have to after we throw it on the balance machine.