MaxSpool Duramax Dual Spring and Titanium retainers.

Rob

As I recall from what you and Nathan told me the truck ran a 9.7x pass then it ate the turbo's and pumped them into the motor. Now do you think it is possible to have run those times with a cam and lifters in the shape you have described? You drove the truck onto the trailer. Nathan put new turbo's on and it broke another turbo on the first pass. After that the motor did not run properly as I recall. Now the motor gets pulled apart and all the damage was found. You told me the oil pump was damaged.

Something happened from the 9.7x pass and the second set of turbo's failing and since there was only one pass between them its fairly easy to figure out when it happened. Figuring out what happened isn't so easy without seeing the parts. One thing to note here is the Duramax does not oil like a normal motor does. The oil goes to the mains, rods and cam bearings. A second smaller passage way sends oil to the heads, into the rockershafts then down the pushrods to oil the lifters and camshaft lobes. This is where I believe your problem is coming from as they are the last to get oil and the first to loose it! Your oil pressure was measured in the oil galley for the main bearing so we have no idea what got to the cam lobes and lifters yet they are trashed. My guess would be from lack of oil but since I'm still waiting for them to show up I cannot say for sure.
 
Steve, don't take my post as that I think you have a bad product, that is not what I was doing. Many parts failed and I never mentioned in the post who's cam we were running, just asking if anyone had similar results.

When I have to purchase expensive parts, I like to find out why they failed. Maybe had nothing to do with a faulty part, but I'd be an idiot not to try and find out why, so I asked a question.

Maybe a rockwell test on the lobs will shed some light. The sweet thing is that all the lobs are in different states of wear. This way a rockwell test of all the lobs my shed some light, from new to the worst. Maybe not. The builder has a contact at comp cams, maybe that'll shed some light.

There are many that can test an give feedback. Some of the above post from you is incorrect.
 
I did not take it that way. What I am saying is there is a lot going on when the failure occurred and without all that knowledge along with the failure it comes out wrong to those who did not know all the facts. Correct what I've said wrong but that's the way I remember it being told to me from you and Nathan.

Until we can get to the bottom of what happened it can happen again if there is an under lying problem. There is a reason and it needs to be found, as camshafts and lifters do not just go away. Typical camshaft failure is in the very beginning when being broke in and that had long since passed. Others have run the same combination as you have (less the turbo's) for over three years of driving and racing without issue so I'm pretty sure there is something that is unique to your case and that is what hopefully will lead to the cause of your issue.
 
I sold out for a few weeks I have another 30 sets in stock. There springs and retainers will go fast, we are building a few muscle car engines for transplant, one with a blower, it’s going to sound really great with headers and true dual exhaust. I designed a cam profile to work with a blower and have no exhaust pressure from turbo’s
One note, the dual spring has the proper spring rate, something that is lacking in any single spring. The dual spring required a custom retainer to retain both springs at the proper height, and keep both centered. I selected Titanium as the material.
 
With all the talk of picking up hp and RPM’s with springs, it’s amazing that people don’t realize that any high performance applications needs springs. It’s not that good springs make more power; it’s that weak stock springs don’t.

I have been working with the Dmax cam profiles extensively, and a well designed cam profile is dramatic.
Don’t under any circumstances conceder a single spring for any high performance application. With the added safety of a dual spring, and a stronger titanium retainer the decision is simple
 
Greg I hate to contradict you, but a lot of top duramax trucks are running our single springs and are having great luck with them.

I don't want to start a war, and I am not knocking your design in any way, as they are a nice looking piece, but I won't let you knock ours either. High 8's in the quarter in a truck not a rail would contradict any thoughts you might have about performance. Almost 40,000 single springs sold in the last year and a half with many over 150,000 miles on them would contradict your statements on longevity and "concedering" a single spring.

Zach
 
If rpm's over 4500 are pursued, dual spring packages are the only Smart way to do it. It's what i'll run along with many of the best builders around. If you dont believe me then please dont look at any pro stock, pro mod or even get close to a top fuel engine.....most of those guys run triple springs...:rockwoot:

Something to consider when comparing single VS dual springs.
 
Single vs Dual springs

You can't compare diesel valve train control to anything you have said Wade. The valves in our heads don't even compare to what the others weigh. 4 valve heads run tinny valves and gentile ramps on the cams. The intensity rate on these cam's are not close to what they run.The light weight/low lift big cam core stuff that a duramax runs doesn't need big spring pressure. Ether spring will work fine. You need to contrtol the valvetrain without to much spring to cost you power. Also boost play's into the spring pressure but again with the little valve you don't have big pressure pure sq in to fight. Jeff
 
IdahoRob said:
How do the cam lobes look after some miles are put on the set-up?

I just tore down an engine with 60 passes and the cam lobes/lifters are shot. Not using these springs. Not sure if this comp cam was faulty or spring pressure too great. Since I had to purchase another cam, I'll send this one somewhere for testing.

Just got me thinking about spring pressures.
Click to expand...

hey rob, ,my last years motor with an s480 and alot of nitrous as you know, lifters showed signs of where over a 1000 horse, not the psi your making but alot of pressure. here's where it gets good, i had the motor rebuilt after boise last year, after i blew it up, at the time the cam looked good, i ran it for 7000 miles before i repulled it for the diesel power challenge and put my rods back in, at this time i discovered the cam was flaking, on the verge of failure, and the newer lifters i had put it, were already showing signs of failure as well due to the cam flaking i believe, i had the test done on the lobs such as you are about to do, and they tested the same from the top to bottom of the lob, only thing we could figure was just sure failure at that level, my oil pump was great, im still running it now on my same motor, im now and since diesel power been running up and over 100 psi as well, i say a new cam every year is the key, no chances, its expensive but not as expensive as these motors we run. just trying to throw an opinion out there.
 
Camshafts and lifters

boost is not going to hurt a cam or lifters. You have other problems. Jeff
 
Stingpuller said:
boost is not going to hurt a cam or lifters. You have other problems. Jeff
Click to expand...

If you’re having cam problems with a Dmax, you problems are with not enough spring pressure; the lifter is pounding the cam lobe. Even thou the valve train is light 7mm valves and all, the ramp rates are much greater. The reason is we can use a greater ramp rate because of the lower rpm application, and lighter parts. Now to expanding on what Diesel power said, a Pro Stock engine uses 7mm valves as well, and there are hollow stem titanium in some engine programs. They also rum 75 mm cams.
Back to the Dmax, the oil comparison is not nearly as relevant in a Dmax, this is the reason for the roller lifter.
If you going to design a good cam program, you must take the profiles and ramp rates to the limit, and use a spring to control valve train. The power in a diesel is to keep timing events within certain parameters, and get the most out of the area under the curve.
I do not like the stock powered metal retainers, I did a push test on them, and they will fail at roughly half the pressure of my titanium, or stainless retainers. I designed a dual spring with progressive rates; a single spring has a huge problem with having a higher spring rate, and more pressure over the nose, as you get close to coil bind. Because I use a dual spring I had to design a custom retainer to go with it as well. Anyone that uses a aftermarket spring with a stock retainer is asking for trouble. My springs retail for $695 , this includes a titanium retainer , if you are going to stay under 4500 rpms , then my Stainless retainers will do just fine, and they retail for $ 625 . I offer Comp D discount of $595 for springs and titanium, and $525 for the springs with stainless retainers.
We had to take the engine out of the NX mustang to do the required R& D check on some of the components we are testing for different manufactures. This engine has 90+ 6000 rpm drag passes , and many land speed passes at well over 5500 for long amounts of time , the springs had lost less than 1% of their original seat pressure. The cam looked new as did the rest of the engine, the engine has over 15,000 miles of street driving .
I have extensive experience with these cams and engine development , This is not a new product for me that I’m trying to give away to test , I’m over 110 set sold now , and still zero problem, my newest cam profiles for the Dmax are really working
 
Just a thought

Some diesels are running over 5k and have high rates of lift, with that and realizing that Diesels have back psi and boost psi higher than what gassers do(smaller ports) then you can see the need for a "better" valve spring. lighter valve or not weight x rpm x boost x back psi, calls for a better spring with more psi.

the weight between the two springs will NEVER show up on a dyno, or at the track. because we are not seeing over 6500rpm's. exstra spring psi on a roller engine like the d-max, will not hurt and can only help, tha is if you realize how a camshaft works, psi is on the ramp up AND down, effectivly canceling out the "high spring psi worries". again common sence IMO
 
Just a thought, we have a lot of customers coming out of the hole well over 6,000 rpm with our single springs on the cummins with 1.940" valves that weigh many times what a d-max valve weighs.

Weight, rpm, camshaft acceleration rates, were all thought about when we designed the springs. Will they cover every aplication under the sun....no. But then again no spring can. Spring mass, weight, rate and frequency can show differences on the Dyno when float becomes an issue. Springs mass is definitely part of the equation and does have to be figured in. We chose a spring that had less mass. That being said there are instances when singles shine as well as doubles. No spring, cam, turbo, injector or port is the end all product for all applications. I can also think of many applications that run a single spring that run well over 6,000rpm.

Giving credit where it is due....Greg is right in that most issues with roller cam lobes is due to not enough spring pressure and not adequately controling the valves.

Zach
 
Last edited:
Single spring with stock retainer, vs. a dual spring with a Titanium retainer for roughly the same price, I have several years with this engine platform, doing cams and springs vs, your just trying to give away sets of them to get people to tell everyone that they are great . I have a more expensive spring package, a dual spring cost more than a single , and the titanium retainer cost more than the spring by almost double. There answer is obvious. I have a single spring that I know will work as well as the others single, and I’ll sell them for $325 a set. But I recommend the duals with titanium retainers, or at least a stainless retainer.
Ill sell my dual spring s as well for $325 , but they require a custom retainer
no way would I ever condone using a stock powered metal retainer
 
With the success of the NX Mustang at Hot Rod drag week, I have decided to put the springs and Titanium on sale for this week $549. I am also making the cams profiles; we have been running thru these successful engine programs available as well. I also have ARP rocker studs for the Dmax as well
Cam, springs and Titanium retainers, as well as rocker studs for $995

I am just received another 50 sets of springs and retainers.
Greg560@aol.com 817 296 4949
 
COMP461 said:
With the success of the NX Mustang at Hot Rod drag week, I have decided to put the springs and Titanium on sale for this week $549. I am also making the cams profiles; we have been running thru these successful engine programs available as well. I also have ARP rocker studs for the Dmax as well
Cam, springs and Titanium retainers, as well as rocker studs for $995

I am just received another 50 sets of springs and retainers.
Greg560@aol.com 817 296 4949
Click to expand...

What is the benefit of running ARP rocker studs vs. a stronger bolt like a 10.9?
 
You must log in or register to reply here.
Back
Top