MaxSpool Duramax Dual Spring and Titanium retainers.

glad I got my order in on time :D ..... was good talking to you Greg will be in touch again
 
Would these springs and retainers cause to much stress on a other wise stock valve train, Daily Driven??
 
custom, greg told me they were good any setup from stock to all out and rpms from idle to 6000+ are no problem....
 
Yes, I speced these springs for a wide range of application with the Duramax engine. At stock installed height they offer a significant increase in seat pressure that keeps the valve on the seat and the roller lifter in contact with the cam profile .
The most destructive aspect of any valve train is uncontrolled valve train motion, and this happens when the lifter doesn’t follow the cam ramps.
These springs will cover any lift practical with the Dmax up to .600+ lift.
I went the route of a dual spring, because a single spring will not get provide the proper pressure from seat to maximum lift.
In today’s diesel world , many are finding just any spring that will fit the spring pocket , and installed height and calling it good , rather than doing the R&D necessary to achieve the proper spring for the application .
You can feel comfortable in the knowledge that these springs are out running on quite a few engines and we have never had a problem. One other aspect is that with a dual spring if you ever have a coil break, you have a second coil to save your valve train
 
This dual spring spring and cam package just ran 202.4 mph at the Texas Mile, this after 10,000 miles of street driving.
I have a adjustable cam gear being made as well , will be ready in the next few weeks , this will go with the H14 tool steel cam , we are doing away with the bolt in the front of the cam , in favor of a threaded partition of the cam , with a big nut , this will allow a stronger nose
 
at 202mph, how many rpm's is he turning? i saw the videos John had, very smooth runs!! didnt even look like it was going that fast.

btw, thanks for the shirt and stickers, and i heard the studs arrived back at home. your check was mailed.

Tim
 
your the only one over there with a Hot Rod Drag Week Shirt , how about a picture
 
I am kinda curious. What is seat pressure at installed height(also what is installed height) on the valve springs.
 
with the new cam and rockers we are putting these springs to the test .600+ valve lift and 6000 rpms.

I I have another 50 sets of springs and retainers in stock, and will renew the Comp D buy for a few weeks

I also have custom cam grinds with any LSA , any firing order , and designed for you aplacation.
 
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.
 
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...

What was your seat pressure?
Rev Kit?
With the roller lifter i would think it would tear the cam up with higher pressure. I am wondering if it was floating and causing the lifter to skip. If the lifter jumps off the lobe it will crash back into it and tear stuff up.
 
Cam and lifters

Spring pressure with these big lifters and wheels would take a LOT of pressure to hurt anything. I would bet it's more of a problem with not enough pressure with big boost than to much. Jeff
 
that or coil bind , there are springs out there that people use a lot of shims with , and the set up is a little short .

but with a 60 mm cam, and big lifters , spring pressure would be the last thing that would kill a cam, call me , and I’ll have a failure analysis done
 
There is a lot more to Rob's failure than meet's the eye. Oil pump failed, main bearings damaged and sucked a couple turbo's through the engine. While I do not know what caused what, there seems to be at first glance a oiling issue going on as well. I would not believe it to be too much spring pressure or coil bind as there is plenty of clearance in there but with 100 + psi boost I might believe not enough spring pressure. Until I get the parts back it's just all guessing.

There is nothing different in Rob's motor build than several others we've done that have a couple of seasons and hundred and hundreds of passes on them without issue. What is different is 100+ psi instead of the normal 70 - 80 psi and the oiling issue.
 
This wasn't an oiling issue according to the machinests and engine builders that I have shown locally. Maybe those guys are mistaken. Although there is no sign of any lack of oil anywhere in the engine or parts.

Rod and cam bearings were perfect. Main bearings were trashed from cap movement (turns out the builder never appeared to have line bored in the first build). Oil pump didn't fail and was running 60 psi when engine was warm. The pump had a worn bushing, but kept pressure up fine.

The whole cam was not trashed but different lobs and lifters. Doen't appear to be chatter from weak spring pressure and big boost.

Not saying what it was, that is why I asked if anyone else has seen failures. We have another engine with only 25 passes or so with the same set-up that I'll be taking a very close look at. I'll have someone inspect the cam.
 
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thanks for sharing all of this rob, they are lessons to learn by for new guys like me
 
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