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

[pbf777]

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

    Yes, in many instances over the decades.     
 

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.

     And yes, we often recommend the use of the steel gears also, but in some instances, with follow up inspections, it just isn't................happy    ; and even when installed properly!       

     Scott.

[blykins]

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

    Yes, in many instances over the decades.     
 

Well that certainly cleared that up.  Much thanks.

[pbf777]

Well that certainly cleared that up.  Much thanks.

     I'm hoping I'm just misunderstanding this comment and that this isn't suppose to be a snide remark, which actually would just indicate child like behavior; and if so I would be disappointed as I felt sincerely that you were better than that?     

     As if one read my post of:
     

     Because in some installations due to a combination of circumstances............

      Particularly someone of experience would understand that there rarely is ever just one singular cause for such failures, but rather often several in conjunction, but also not necessarily for example all of those I listed, which I have attributed to such failures, but still with the same outcome as I have observed in different instances.   

      Scott.

[chilly460]

I think I’d need to hear “This is such and such core material with Rockwell such and such and no steel gear is compatible so you’ll have to run a sacrificial bronze gear”, a specific scenario, rather than a general statement.  I just don’t see why one would run a bronze gear, I’ve seen one fail in a light street use/strip scenario with a mild solid roller.  The constant wondering when it would fail seems absolutely unnecessary since steel gears are available, had one running going on 4yrs now in my car. 

How did OEM handle this with their rollers?  Cast gear on a steel core, or steel distributor gear?  Doesn’t seem like it needs to be complicated being that OEMs have run rollers for over 30yrs (granted newer engines don’t have gears).

[67xr7cat]

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.

For sure not knowing your supply chain source is a problem in this day and age.

[67xr7cat]

I think I’d need to hear “This is such and such core material with Rockwell such and such and no steel gear is compatible so you’ll have to run a sacrificial bronze gear”, a specific scenario, rather than a general statement.  I just don’t see why one would run a bronze gear, I’ve seen one fail in a light street use/strip scenario with a mild solid roller.  The constant wondering when it would fail seems absolutely unnecessary since steel gears are available, had one running going on 4yrs now in my car. 

How did OEM handle this with their rollers?  Cast gear on a steel core, or steel distributor gear?  Doesn’t seem like it needs to be complicated being that OEMs have run rollers for over 30yrs (granted newer engines don’t have gears).

Well the day you have a steel gear on a billet cam fail and wreck that cam you may see it different.  I have NO problem with a steel gear used on a cam that is compatible with it. I can tell you when one gear is harder than the other and there is wear the harder gear will win, but if it is a close race they both may get damaged.  While you had a bronze gear fail, I've personally have seen them last 10,000 miles.  Proper install and proper material matter.  Get that wrong and it won't last.  Another question how many miles you put on your car a year?  A lot of these guys don't even put 3,000 miles a year on their cars. Do you feel pulling the dizzy once a year is too much to check the gear? 

One thing with a bronze gear it takes the wear, not the cam. If I do not know for a fact that the cam and dizzy gears are compatible I'd rather be changing a dizzy gear than a cam.

Another thing to consider a bonze gear will not wear a cam gear.  A steel one will develop a wear pattern.  Crane recommended NOT to use their steel gear on a cam that was run already with a steel gear.  Now sure guys have done this 1,000 times and got away with it, but every time you put another gear on the cam has to re-wear to it. Considering what the OP wants to do running a bronze gear on his "break in" dizzy be the way to go for just this reason. 

I'd suggest asking the dizzy gear company what cam core types they say are compatible to answer your specific example question, although here is a link to a thread where Mike Jones (7th post in thread) talks about cam core compatibility:

https://www.speed-talk.com/forum/viewtopic.php?t=59407

And here is one where Dave McLain had a steel gear fail on a steel roller cam after 3,500 miles.  Is the 8th post in the thread.

https://www.speed-talk.com/forum/viewtopic.php?f=1&t=48321

Is interesting looking at that Holley's dual sync dizzy page. Says comes with a hardened steel gear, then goes on to say bronze gears are available for billet roller cams.

https://www.holley.com/products/ignition/distributors/holley_efi_dual_sync/parts/565-205

As for the OE's keep in mind they control the cam and dizzy gear material as well as the heat treat and machining.  Using aftermarket parts not the same as OE ball game.

[Posi67]

All I have to add is that I put a bronze gear on my (not for racing) Unilite about 16 years ago and have used the same setup on 3 engines with 3 different Cams. 2 were/are Solid Rollers and one was a cast Solid. Still running to this day with no obvious issues. Granted, not a high mile car but hundreds of Drag Race passes. Never had a steel gear nor saw the need however your results may vary.   

[blykins]

Well that certainly cleared that up.  Much thanks.

     I'm hoping I'm just misunderstanding this comment and that this isn't suppose to be a snide remark, which actually would just indicate child like behavior; and if so I would be disappointed as I felt sincerely that you were better than that?     

     As if one read my post of:
     

     Because in some installations due to a combination of circumstances............

      Particularly someone of experience would understand that there rarely is ever just one singular cause for such failures, but rather often several in conjunction, but also not necessarily for example all of those I listed, which I have attributed to such failures, but still with the same outcome as I have observed in different instances.   

      Scott.

Scott, I will say that I was equally disappointed in your response.   You are a man of wordiness and I was hoping to at least get some semblance of a coincidence.  I have torn down and freshened up many Fords over the years and have never pointed a finger at a distributor gear and thought, "I need to swap that over to bronze."  So, I was very curious as to what correlation you drew; if these situations were solid rollers only, high spring pressure, low spring pressure, gear drives, etc., etc.  Equally so, you could have just said, "To be honest Brent, it's been a long time and I can't remember."  Or, you could have said, "Let me think on that one."  I saw a drip of sarcasm on your reply, and that post didn't lend itself to shining any light whatsoever.

[blykins]

All I have to add is that I put a bronze gear on my (not for racing) Unilite about 16 years ago and have used the same setup on 3 engines with 3 different Cams. 2 were/are Solid Rollers and one was a cast Solid. Still running to this day with no obvious issues. Granted, not a high mile car but hundreds of Drag Race passes. Never had a steel gear nor saw the need however your results may vary.

Dale, if it were a dedicated street car, I think it would have a different outcome. 

Even if you had the distributor in 3 different engines and put 1000, 1/4 mile passes on each, that's only the equivalent of driving 750 miles.  The bronze distributor gears will usually go several thousand miles and then they start to get sharp. 

[My427stang]

I have pulled a few home with bronze gears over the years.  Been a long while, but the last one was a buddies 68 302 Mustang, wore it off entirely the shape of the cam gear, all the way around the gear, like it was made out of soft plastic

In every case, the car was a driver. 

[67xr7cat]

I have pulled a few home with bronze gears over the years.  Been a long while, but the last one was a buddies 68 302 Mustang, wore it off entirely the shape of the cam gear, all the way around the gear, like it was made out of soft plastic

In every case, the car was a driver.

So why do you think this steel gear failed on Dave McLain after only 3,500 miles?  Is the 8th post in the  linked thread.

https://www.speed-talk.com/forum/viewtopic.php?f=1&t=48321

So why do you think I got 10,000 miles on a bronze gear?  Was a Lunati solid roller street cam back when Joe Lunati ran the place.  Was a street/strip car.  Took several years to put that mileage on it.  Used to check it once a year.  Will say the 1st one did not last long, but after learning the correct way it lasted a lot longer.

Final question, how many miles do guys on here put on their rides a year?  Am sure someone will say 20,000, but most of these cars are getting old and bet sit more than anything. the OP is building a 511ci ERA Cobra.  I'd like to know how many miles a year that car will see. 

[My427stang]

I have pulled a few home with bronze gears over the years.  Been a long while, but the last one was a buddies 68 302 Mustang, wore it off entirely the shape of the cam gear, all the way around the gear, like it was made out of soft plastic

In every case, the car was a driver.

So why do you think this steel gear failed on Dave McLain after only 3,500 miles?  Is the 8th post in the  linked thread.

https://www.speed-talk.com/forum/viewtopic.php?f=1&t=48321

So why do you think I got 10,000 miles on a bronze gear?  Was a Lunati solid roller street cam back when Joe Lunati ran the place.  Was a street/strip car.  Took several years to put that mileage on it.  Used to check it once a year.  Will say the 1st one did not last long, but after learning the correct way it lasted a lot longer.

Final question, how many miles do guys on here put on their rides a year?  Am sure someone will say 20,000, but most of these cars are getting old and bet sit more than anything. the OP is building a 511ci ERA Cobra.  I'd like to know how many miles a year that car will see.

Steve, let's take these one at the time, starting with a blanket rule we all follow (I think)...do what works for you.  I have no stock in steel gear production, but I push a few engines through, not as many as some, and my position based on experience is, I don't want to stand behind a bronze gear.

However, I will answer the best I can what my WAG is on things that I have no information, nor have I seen the parts or setup

Dave McLain is a sharp cat, but that thread doesn't say what his failure was. Without knowing, could have been anything, and a bronze could have failed as well.  I will say that I'd expect him to pay attention to details.  However, if it took out the cam, so the pin either came apart, which could easily have been a depth problem, or there was a mismatch of materials, or not sure on a 460 or 351C, but on an FE, all it takes is an unmodified ARP cam retaining bolt and you lose oil to the distributor...I bet 50% of the guys don't even look at that.  Who knows what happened .  No idea with the data we have. 

Why did yours work? No idea either.  Actually, I have not had a failure on an FE, the others were all other Fords.  However, I recently rolled into Kentucky with a u-joint falling apart, couldn't find a joint, but found a cap from another one that fit.  New rollers on a damaged joint, I was in a bind and laughed to Brent about what a hack to get home (and if I even would).  Shouldn't work, put 2500 miles on it to get to Maryland and then home after it stayed tight and quiet, got home, rollers cleaned up the joint and it looked and felt new.  I replaced them both, but could have ran it. Shouldn't happen, but did.....  Maybe the old cam / old bronze gear was a little better, maybe zinc in the oil in the old days, I wish I could give you an answer

Last, the mileage, I used to drive the wheels off my own, life got busy.  I see guys that to 2000 a year to 12000, but there are cold starts too.  My thought though is if the material is sacrificial, it is continuously sacrificial, not just all of a sudden at 10K.  I don't particularly want to push bronze into the oil more than normal wear does with other materials.

However, back to rule 1, do what works for you, you have to live with it, not the other guy.  I am all about us sharing what we do, and I have ZERO desire to be in, never mind win, a debate.  If someone comes to Nebraska....no bronze gear unless there is no other choice, and even then I am going to do everything I can to exhaust the options.  I also have a local guy that uses Eagle cranks on every FE build, not for me.  These guys are my buddies, but it doesn't mean we see and do the same thing.  I think he will see a broken crank if he starts making the power we make.  He says "I haven't yet" well, how do you argue with that, but I am not using one LOL

[Falcon67]

Previous life before serving 23 years before the IT mast was manufacturing.  Lots of precision mechanical things, power transfer, heat treat, etc.  So familiar (well, it's been a long while though) with issues of dissimilar metals running next to each other.  I've had (as noted earlier) the steel gear on billet cam fail deal.  I do not have the equipment in my shop to make failure determinations like Rockwell testing, etc.  All the install parameters were correct, not started dry, all that. The gear could have been faulty, core issue - who knows.  It passed all the static tests like every other engine build, then it just didn't last very long. I do have a budget and to lose a $300 cam after a few passes is a hit I didn't want to repeat.  I just made the call I wasn't going to put another quarter in the same Coke machine that already took my money and didn't give me a Coke.  So bronze it was - MSD I think, have to find the invoice.  It was installed on the same shaft, same installed dimension, new cam and it's been just fine.  Have no issue with yanking it out once in a while for a look.  It's actually easier to pull the distributor to pour 8 quarts into the pan vs nursing 8 quarts though a tiny baffled hole in a valve cover. There just seems to be this perception out on the internet that a bronze gear will fail before you get to the end of the block. I've got cast gears sitting around with slightly to medium sharp teeth from running with HV oil pumps on cast flat tappet cores that have less time on them than the bronze gears I'm using now and the bronze seems to be holding it's own.  It may well not be necessary but it's working in my application.  Any besides, they are kinda pretty with that shiny gold look.

[67xr7cat]

Hi Ross, good post. Think what is important here is application matters and each should make an informed decision. Falcons 67 post give some good perspective too.  When you have known parts think is fine. If is a question sometime better take the safer option. Also with some steel gears in short supply guys should not just discount bronze as an option.

I can tell you why my bronze gear lasted that long and btw that was a 351w. Devil is in the details always. As for Eagle years ago was building a 460 and my old boss said why not put a stroker in it and got out the Eagle catalog. I said guys on the internet say stay away they break. He looked at me said never had that problem been using them for years. 15 years later still does and I can tell you he has some engines making 1,000+ HP.

To me I try not to speak in absolutes. Everyone can say what does or does not work for them, but in the end the best decision is an informed decision and that is a win for everyone

[TJ]

When I think of all the places we use gears (trannies, differentials, timing gears, etc) and expect them to last indefinitely, it's puzzling why some folks just accept cam gears and dizzy gears are too difficult to match for longevity.  To me it's one of those details consumers should require in a product...gears must be compatible and should last longer than an oil change interval. 

When I suspect two components are not compatible, I look for components that are. 

Not trying to be argumentative here, I'm just puzzled.