shot peening a distributor gear for a roller camshaft

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Bronze Barracuda

Bronze Barracuda

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Anyone have any thoughts on shot peening a distributor gear, as to be able to use it with a roller camshaft?
It seems to be a difficult mission to locate/find a Melonized distributor shaft. Or for that matter just a bare shaft that I could mount a melonized gear onto.
Hughes has the gear on its own but no shafts in stock to mount them on. Nor do they have a gear and shaft as a complete package. Mancini has a Bronze Milodon one. But I think I'd read somewhere that the Bronze ones are designed as a wear part and not really made for street use.?

I am seriously considering having one of my spare ones shot peened??
Thanks for any ideas.

Milodon 21535 Oil Pump Driveshaft

Edit; Is it possible to remove the gear off of a stock oil pump driveshaft?
 
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Yes to removing the gear from shaft.
However, the pin is a pain to remove at least
for my elderly hands.

I do not think shot peening would do the job on the gear.
 
GTX JOHN said:
Yes to removing the gear from shaft.
However, the pin is a pain to remove at least
for my elderly hands.

I do not think shot peening would do the job on the gear.
Click to expand...
Did certain years have pins, to be able to remove the gear. The two that I have do not have a pin, that I can see. Anyway to tell if they may or may not be melonized?

Maybe a lot of heat and a press?

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Hughes has the melonized gear in stock.
 
I suspect melonizing is a variation of case hardening, but haven’t been able to find out how the process is done yet or with what materials yet.
 
Well that worked! :lol:

Not sure if the gears from Howard's can be pressed on or if they are only designed to be used with a pin?

Pretty sketchy way of pressing it out. 5 minutes of MAP Gas and then pushed my little 12 ton press to it's limit. Leaning into the press with nearly all my body weight, I took a moment to put on a face shield, then leaned into it a little bit harder. It let out a loud SNAP, I instinctively turned my head. I turned back to see where the bolt flew off to and to my surprise it was still there. A few more easy pumps and it was free from the gear.
Probably best to put some sort of shield infront of the press for next time!

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Bronze Barracuda said:
Yeah I called them this morning, but they have no shafts available to mount them on. I think I may try and press one of my old gears apart from the shaft
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Just do that. Make sure you take a measurement of WHERE the gear is on the shaft so that you can locate the new one accordingly. If you want to pin it, they can be easily drilled and pinned. A standard roll pin will work fine. I don't know what size roll pin. 3/16" maybe?
 
RustyRatRod said:
Just do that. Make sure you take a measurement of WHERE the gear is on the shaft so that you can locate the new one accordingly. If you want to pin it, they can be easily drilled and pinned. A standard roll pin will work fine. I don't know what size roll pin. 3/16" maybe?
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Its already off, I suppose I can use my other one as a reference. Maybe I will get the shaft shot peened to strengthen it up a little?
 
Bronze Barracuda said:
Its already off, I suppose I can use my other one as a reference. Maybe I will get the shaft shot peened to strengthen it up a little?
Click to expand...
Is it a stock shaft? Are you going to run a HV oil pump?
 
Melonizing is a similar process to nitriding.
The stock factory shafts are of a steel similar to a drill bit, very hard if near impossible to drill.
The MP shafts were 4130 or 4340 Moly steel, a hard steel that can be drilled; hence they were drilled & pinned as a safety measure. Presume aftermarket, Hughes etc, shafts are similar. Because this steel is softer, it will have significant wear after a while when used with a bronze bush. I used them with an alum bush...& had no wear problems.
 
Bewy said:
Melonizing is a similar process to nitriding.
The stock factory shafts are of a steel similar to a drill bit, very hard if near impossible to drill.
The MP shafts were 4130 or 4340 Moly steel, a hard steel that can be drilled; hence they were drilled & pinned as a safety measure. Presume aftermarket, Hughes etc, shafts are similar. Because this steel is softer, it will have significant wear after a while when used with a bronze bush. I used them with an alum bush...& had no wear problems.
Click to expand...
Ok what it appears my setup at the moment will be is a factory shaft with a Hughes melonized gear riding in a bronze bushing
 
At one point in time Doug Dutra was getting slant six oil pump gears hardened to solve oil pump gear failure. Since his shop burned a few years ago you rarely see him on slantsix.org but maybe someone could PM him for some Insite on his experience.
 
Could a stock magnum distributor shaft and gear be used since the magnums are roller? I've heard both ways and am having a hard time finding the melonized one on a shaft also. Already have a magnum shaft sitting here.
 
milo123 said:
Could a stock magnum distributor shaft and gear be used since the magnums are roller? I've heard both ways and am having a hard time finding the melonized one on a shaft also. Already have a magnum shaft sitting here.
Click to expand...
Apparently Chrysler didn't use billet camshafts for their roller blocks.
If it's a billet cam then we need to use a melonized gear
 
Bronze Barracuda said:
Apparently Chrysler didn't use billet camshafts for their roller blocks.
If it's a billet cam then we need to use a melonized gear
Click to expand...
Is your cam a Billet solid roller?
Or is it a hydraulic roller?
Sorry if I missed that if it was mentioned.
Most or maybe all street hydraulic rollers are just a cast core, that usually any cast distributor gear will work.
Billet steel cam usually requires a bronze distributor gear.
At least that's what I've seen...
 
Mopar69gts said:
Is your cam a Billet solid roller?
Or is it a hydraulic roller?
Sorry if I missed that if it was mentioned.
Most or maybe all street hydraulic rollers are just a cast core, that usually any cast distributor gear will work.
Billet steel cam usually requires a bronze distributor gear.
At least that's what I've seen...
Click to expand...
A billet hydraulic roller
 
Bronze Barracuda said:
A billet hydraulic roller
Click to expand...
Wow ok interesting.
The cam manufacturer recommended a melonized gear not bronze?
I mean I would do whatever they tell you
Just seems odd to me.
every Billet cam I've ever used was always told to run a bronze gear.
But those were Billet Solid Rollers...
not sure why there would be a difference
Solid vs. Hydraulic Billet
But thank you, I might just learn something.
Carry on
 
I think it's a mistake to use a stock shaft with an HV oil pump, but it's probably too late now.
 
RustyRatRod said:
I think it's a mistake to use a stock shaft with an HV oil pump, but it's probably too late now.
Click to expand...
I was thinking the same thing. When I ordered the oil pump it was supposed to be a regular pump. For some reason they shipped a HV pump.
But not to late to switch to a regular oil pump. :thumbsup:
 
Bronze Barracuda said:
I was thinking the same thing. When I ordered the oil pump it was supposed to be a regular pump. For some reason they shipped a HV pump.
But not to late to switch to a regular oil pump. :thumbsup:
Click to expand...
I'd just order an HV shaft and swap the melonized gear on.
 
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