96capricemgr

$93 sounds like full list price you can probably cut that number in half with somewhere like GMpartsdirect or friendlier local dealer.

Still you have to address why it failed. They are rather reliable with the proper cam gear material and standard volume pumps.

Was the existing pump a HV unit or is the cam aftermarket?

jeremyhurt

It is an aftermarket cam called GM Performance LT1/LT4 Hot Cam Kit...

12480002 - JEGS High Performance

I did find the part for 40 bucks on ebay...

Zaknafein

Could be a number of things that would cause the gear portion to fail; mesh clearance, tolerances, metallurgical properties... could be difficult to find a failure mode unless you really know what you're doing.

Not too uncommon on these engines, especially once an aftermarket cam is swapped in.

*edit*

While you're in there, you might want to take a look at your bearings to see if you did any damage...

Good luck.

96capricemgr

This happens sometimes with aftermarket cams because people trust folks they should not and get the wrong gear. This IS NOT known to be a problem with proper cams like the HOT cam.

I would take a second look at the oilpump and if it is a HV unit replace it with standard volume. HV pumps are known to cause this kind of damage.

jeremyhurt

Out of curiosity,

How does Higher Volume of oil cause a gear to break?

96capricemgr

Continuous higher load while operating.

They can force a little more oil through the bearings by creating higher pressure at earlier rpms than a standard volume but in reality at high rpms the HV pumps have just gone into bypass sooner. There is a spring in the pumps that limits max pressure, when that pressure is reached the oil "bypasses" and gets dumped back to the pickup, this just happens at a lower rpm with a HV pump. So they really only push more oil through the engine at idle and cruise when there is no load anyway.

Then on engines that turn more rpm than our computer will let us HV pumps tend to cavitate, they suck so hard on the oil from the pan it creates gas pockets which are not so good for the pump or the bearings.

There are engines that need oil pump upgrades, the gen1 and gen 2 smallblock Chevys are not among them.

jeremyhurt

OK.. thanks for the advice

Zaknafein

It could happen with any cam to be honest. If the gear has a nick or bur, it can take out the drive gear in a hurry. Not enough root clearance and/or improper mesh can do the same. Different wear patterns can cause accelerated wear as well.

I worked in failure mode analysis for a number of years, seen a lot of things that get by QA departments and it's actually worse in large parts operations where batch inspections are the norm.

I'm curious to know--in your opinion--what the "proper" cams are?

Is that to imply that no one but GM knows how to properly cut, inspect and heat treat a cam drive gear?

Who do you feel is not up to the task of doing this and how did you arrive at your conclusion? If any of these did cause drive gear problems, were you there to inspect the cam gear upon assembly?

The HV pump will put more load and wear into the cam gear but I wouldn't assume failure because of it.

My advice would be to change the drive gear any time a new cam and/or oil pump is added.

Quality pumps do feature anti-cavitation grooves to combat some of these issues and they've worked fine for HP engines for years.

I do tend to agree that a standard volume/pressure pump is more than up to the task in some engines, with standard bearing clearances and moderate viscosity oil.

The confusion probably comes from not understanding why the HV/HP pump is used in those builds designed around them.

96capricemgr

Your problem here is the "engineer" in you.

My comments are based on real world experience and more than a decade of regular presence on several LT1 specific forums.

Far as who can get a cam right, mine is not a GM cam.

Those comments had to do with a certain vendor who was hugely popular for quite some time who routinely ordered cams from his supplier wrong.

Zaknafein

Well thank you Freud. Was this suppose to offend me?

Sorry it offends you but most of us are use to asking questions and evaluating data, hence my questions about what you've actually seen and how you quantified it.

I see now that we should just accept what you've said without contest. This is good, I like to know the types of personalities I'm dealing with.

Certainly answered my question...

Seems easier to name the vendor in question does it not?

96capricemgr

Not meant to offend atall.
Just the engineer mentality often overshadows real world practical experience.
You are technically correct that a damaged gear or poor machining etc could cause a failure BUT from a practical standpoint we don't see that happening.
The trick would be to use engineering knowledge to interpret real world long term observation and data. Most folks see something and think it works and just believe without understanding, engineers often understand all the theory but struggle when faced with a real world contradiction to their theory. Someone on another forum who has overengineered and underperformed a LOT with the LT1 platform has a quote in his signature along the lines of "it works in reality but does it work in theory?"

Far as naming the vendor he has been banned and other vendors that were using him have put some distance between themselves and him. No need to stir the pot when there are a few folks around who still believe in that false prophet. The guy was so bad he was selling valvetrain setups that sometimes ate themselves in 2-3000miles.

Far as who else can get a cam made right just about anywhere, you just need to make sure your middleman is competent and ordering the cam blanks right. There are very few blank manufacturers and a whole lot of brands and smaller shops grinding the lobes. I know my cam from Advanced Induction has a Lunati EverWear gear those are compatible with the stock drive. I have never bought a new oilpump drive or had any problem with one or an oilpump and I have been screwing with these things for over 12 years, daily driving them too up till a little more than a year ago.

Far as HV I understand some builders set bearing clearances loose. As well as the stock shortblock holds up to 500+fwhp I think it silly to suggest that HV or thick oils are needed for the VAST majority of street/strip motors.

MachinistOne

I am in agreement with 96capricemgr

jeremyhurt

Its a nice day when you have a thread with so many comments and opinions. I have only owned this car with the LT1 for a couple months, therefore I lack experience and I greatly appreciate all this input. Pease feel free to comment more and I will for certainly take advantage of the experience you folks have.

At the end of the day, I feel like I have gotten plenty of information from the thread, but I still don't feel comfortable knowing what is recommended.

I know I will be replacing the oil pump (What type I am unsure). I know I will be replacing the oil pump shaft and gear. Other than that, I will just have to hope things work out.

What oil pump would you guys recommend? Would a Melling HV or non HV?

Which would be more applicable with my set up?

Again, thanks alot...

shoebox

Melling 10554 (it's SV) with their pink spring or a GM white spring (same 70# spring).

ACE1252

Ditto. Also, replace the oil pump drive shaft with a Melling IS-55E. Gets rid of the nylon sleeve.

Edit: Look like on Summit, it comes with that drive shaft. Not sure if it does in other stores.
http://www.summitracing.com/parts/MEL-10554/?rtype=10