Cast iron Dist. gear on Crower hyd. roller cam for break in

[SAcobra427]

Getting ready to fire up my all new 511 ci (BBM heads and block) that will be running a Holley EFI Sniper Stealth setup. I am also going to be using the Holley Dual Sync Dist. that goes with it but would rather just run a regular single point dist. for the initial start up just to simplify things. My question is will running the cast iron gear on the regular dist. be ok to use on the steel gear of the Crower hyd. roller cam for the first 20 or 30 min of initial runtime ?
Thanks for any help you can provide.

PS FYI, already left 2 messages at Crower about this over the last 3 weeks with no responses 

[blykins]

It won't last.  Need to use the steel gear.

[SAcobra427]

OK Brent thanks for responding ! 

[pbf777]

     Well, yeah, ..........it won't last but, it has often been practiced to initially utilize a cast iron gear on steel mechanical roller cams in order to effectively "break-in" or "work-down" the sometimes less than ideal gear surface as presented by the manufacturer prior to swapping to the as required bronze gear.     

     Trick is, knowing when to get the iron gear out before it starts shedding excessive material, perhaps then instead of providing a smoothing effect rather damaging the camshaft gear surfaces, not to mention excess particulate about in ones' oil, and this duration will vary depending on several variables in the function of the relationship.     

     Scott.

[Jb427]

I have seen cast steel gear last less then 20min running on a roller cam

[blykins]

     Well, yeah, ..........it won't last but, it has often been practiced to initially utilize a cast iron gear on steel mechanical roller cams in order to effectively "break-in" or "work-down" the sometimes less than ideal gear surface as presented by the manufacturer prior to swapping to the as required bronze gear.     

     Trick is, knowing when to get the iron gear out before it starts shedding excessive material, perhaps then instead of providing a smoothing effect rather damaging the camshaft gear surfaces, not to mention excess particulate about in ones' oil, and this duration will vary depending on several variables in the function of the relationship.     

     Scott.

Or you could just put a steel gear on from the get-go.   

[TJ]

I rate myself as a beginner mechanic and even I think swapping in a steel gear is a relatively simple and quick task...with instructions on how to get the measurement.

I have no idea why bronze gears are available.  Is there a benefit in racing?

[Falcon67]

I run all bronze on mine.  It's just easier on "short run" engines and there's no fuss about what's compatible with what.  If you order an MSD crank trigger distributor it comes with a bronze.  I ran a steel on steel in a race 393 and it chewed up both the cam and distributor gear after about 4 race weekends.  Not sure why, it just did.  Switched to bronze and haven't had any issues.  The bronze gear in the 351C door car has about 4 years of racing with a lot of passes on it and it looks just fine, very little wear. And that's running an HV pump with 72 lbs pressure cold, 60 lbs hot at 2000+.   

If it does chew up a bronze gear, you're not going to have a motor full of oil flavored with steel dirt that acts like an abrasive slurry like you get with cast or steel.  Iron/steel makes a hella mess.  And the only way to get rid of it is to pull it completely apart and wash every little piece LOL.  So best to start out with compatible materials. 

[blykins]

I have no idea why bronze gears are available.  Is there a benefit in racing?

There is none.   To be honest, I really don't know why bronze gears are available either.  They don't last long.  A steel gear on a steel cam will last forever and so will a cast iron gear on a cast iron cam.  Anytime you get a material mismatch, one side will inevitably show some wear. 

[My427stang]

I would never recommend an iron gear on a steel cam over time.  However, I also don't know how to define what that time is, because it could be an expensive experiment and have no desire to try.

I REALLY don't like bronze gears, but knowing that the dual sync has a gear that will work, and this is temporary, and you can't find a steel gear,  I'd go bronze.  However, the cost difference between steel and bronze is minimal if you can find a steel gear choice.

You may want to consider a borrowed aftermarket distributor or even purchase a used one, much easier to find a steel gear

PM me though before you mess with that dual sync, I learned a lot about them (and Holley programming/operation) on my most recent Terminator X install and would be happy to share, especially if you are going Terminator X, although Sniper is very similar.

[pbf777]

There is none.   To be honest, I really don't know why bronze gears are available either. 

     Because in some installations due to a combination of circumstances such as: deficiencies in the basic engineering from the O.E., execution in manufacture of the components in hand, the abruptness in velocity changes with greater forces presented in the more aggressive mechanical rollers, along with flexing and movement in the position of the gear relationship, vibratory effects particularly on the displacement of the lubricant, and even the fact that the lubricant is a compromise, as that which one might prefer as a "gear-lube" probably isn't going to be appreciated by the sealing rings manufacturer, add heat and other excessive loadings,..........one sometimes needs a 'softer', if only a sacrificial component in the relationship for a reasonable outcome. 

     That's why.       

     Scott.

[67xr7cat]

Bronze gears have their place. Main advantage is you don't have to worry about gear compatibility possibly damaging the cam gear.  Not all steel cams are the same material, not all cast are either.  Best way is if you know the cam material is to ask the distributor gear maker if the gear is compatable.

Bronze gears will wear out they are not a 100,000 mile solution, but properly installed can last at least a few thousand miles.  I had on last 10,000 miles. Also not all bronze gears are the same quality.

If you have a drag car and a billet steel cam bronze is a safe easy choice and provided the gear is made from ampco45 and properly installed, in that application it should last a long time.

[pbf777]

Not all steel cams are the same material, not all cast are either.  Best way is if you know the cam material is to ask the distributor gear maker if the gear is compatable.

     It is true that the camshaft cores are not all the same; problem is the so-called manufacturer who's name it on the box truly doesn't know either anymore as the cores are a buy-out from someone else manufactured where and of what?   

     Scott.

[blykins]

There is none.   To be honest, I really don't know why bronze gears are available either. 

     Because in some installations due to a combination of circumstances such as: deficiencies in the basic engineering from the O.E., execution in manufacture of the components in hand, the abruptness in velocity changes with greater forces presented in the more aggressive mechanical rollers, along with flexing and movement in the position of the gear relationship, vibratory effects particularly on the displacement of the lubricant, and even the fact that the lubricant is a compromise, as that which one might prefer as a "gear-lube" probably isn't going to be appreciated by the sealing rings manufacturer, add heat and other excessive loadings,..........one sometimes needs a 'softer', if only a sacrificial component in the relationship for a reasonable outcome. 

     That's why.       

     Scott.

Can you name a specific instance in where you have seen this as being "necessary"? 

I've never used a bronze gear on any Ford engine....hydraulic roller, solid roller, 5000 rpm, 9000 rpm, high volume pump, standard volume, I've never seen an instance where I needed bronze. 

[TJ]

I'm probably over simplifying it thinking if a ring and pinion set in a differential can push a car/truck for 100's of thousands of miles, then I expect to have a dizzy gear able to turn an oil pump for about as long.  That's why it's hard to imagine using bronze outside of racing where the engine may be torn down regularly anyway.

I can see how some guys might feel more comfortable with bronze.  I'm just inclined to only buy a cam/gear combo that will last longer.