VETDRMS

Well, after being on hold for 30 minutes I got to talk to Comp Cams "Cam Help"

He really did not have much of an explanation for the offset wear pattern however he did have a few interesting things to say.

1) Comp does not recommend using MSD distributor gears with their cams, according to "them" they have more of a square cut gear tooth and are harder on the cam.

2) The "Street" rollers with "CAST" gears are not cast, but are what they call "Off Tempered", harder than cast, yet software than steel, "they" said, however they are "kind-of" cast.

3) I have excess cam endplay, or "walking." I set it with 0 clearance without gasket, and installed timing cover gasket as spacer ~.015-.025"
Recommended endplay is .002"-.010" with the ideal being .006"

4) He said if I went through one gear chances are it killed my cam. :(
However he instructed me to pull it and inspect it. If the damage is not that bad he said I can use their polymer gear and it will "wear to fit" the pattern on the cam. :eek: And stop wearing once it fits. But at $100 its pricey.

5) He said the melonized gear is the way to go with their cams, from GM The only problem is MSD decided a .500 shaft is better than .491. Apparently that .009" is good for something, and not only to make you buy "their" gear. :mad

So anyways, I think I am going to try the melonized gear from GM and see how it goes. From just inspecting the gear through the distributor hole it looks "ok," but does have some shiny spots.

I am also considering talking off my cast aluminum timing chain cover in favor of a stock one so I can "set" endplay using the bolt on my waterpump to press in the cover.

Wish me luck! Spring is hear and i'm going crazy with it in the garage.

:cheers:

MotorHead

Just get one of those aluminum cam buttons and shave it down until you get the desired endplay. I just bought another Cloyes aluminum timing cover with the ajustable button 95 bucks from Jegs.

How are you going to get the melonized gear from GM to fit your MSD if they are not the same diameter ?

I know a guy who is running this cam in his race car I will ask him what he is running for a dist. gear tommorrow. :D

I hope Cam Help is an 800 number cause they will be getting a call from me shortly :lol:


[Modified by MotorHead, 9:43 PM 4/5/2004]

2000-A4

I used a Comp cam “Street Roller” and was told I could run the cast gear…it did not last street driving. I installed an MSD bronze gear and the problem went away. I also use a cam button, however it is with a stock cover so there’s some flex. Good luck, keep us up-to-date on the out come.


[Modified by 2000-A4, 3:57 AM 4/6/2004]


[Modified by 2000-A4, 3:58 AM 4/6/2004]

VETDRMS

Motorhead I honestly think the endplay I have is fine. I had this same setup with the HR and had NO problems.

The melonized gear needs to be honed .009" pretty quick and easy job for any competent machine shop, or incompetent ones as well. :lol:


Let me know what you find out about your friend.

Yes, it is a 800 number: 1-800-999-0853


2000-A4 Its good to hear i'm not alone! :yesnod: Did you have any damage to the cam gear itself? Or did it just tear up the dist. gear?
I am going to get a melonized gear tommarow and hone it out.

Also, what kind of wear pattern did yours have?

Thanks!

:cheers:

redvetracr

My bronze gear was opened up to fit the MSD .500 shaft, it took about 2 minutes on a rod hone and that includes a couple of trial fits. I have my waterpump "stop bolt" set about 1/4 turn backed off from hitting the cover, too tight might of destroyed the last torrington cam bearing. I would think MSD uses a .500 shaft because it`s probably easier to buy .500 material than it is to buy .500 material and cut it down to .491, same with whatever they use for bearings... ...redvetracr

PS: I always use (and will continue to use) Ultradyne camshafts, you make the phone call and the owner and camshaft designer Harold Brookshire is on the other end of the phone...unfortunatly Harold had to go to work for Holley/Lunati so I guess I will have to call the BEST IN THE BUSINESS at a different number...


[Modified by redvetracr, 10:32 PM 4/5/2004]

2000-A4

It damaged one gear so badly, I couldn’t determine a pattern. The next one, I ran for just a little while and the edges of the teeth were getting thin. I assume at some point it would just rip the teeth off. It did not damage the cam gear.

VETDRMS

redvetracr Thanks for the info. You are probably right about the dist. shaft. Its all too often much easier to be the cynic. I have heard good things about Ultradyne, for me the off the shelf solution seemed the way to go. However I probably left a fair bit "on the table." At the very least it will give me reason to "updgrade." :yesnod:

2000 A4 I'm glad to hear there was no damage to the cam gear. I can see a "shiny" surface on the gear from the dist. hole, but the teeth look fine. I may just get a melonized gear and give it another go.

Thanks for all the help!

Solid LT1

I agree with Red Vette! Ultradyne user here, ther're not much on advertising but the best on design. I know that Comp Cams started on some of Harold's designs but, Comp does have some decent profiles in catalog now. I am Sorry to hear the Holley conglomerate has bought Ultradyne, I don't think very highly of their management based on my expiriences frm years ago when they were buying everyone in sight with the aspirations of going public on Wall Street and crapping on their long term employees.

redvetracr

At least Holley/Lunati "buys" their competitors unlike C*mp c*ms who just steals the technology (or the employees)...there is a small tool company up here, C*mp c*ms wanted to buy him out at pennies on the dollar, when he said FU** Y*U they said thats alright we will just copy all your stuff.....to be honest Harold is much happier where he is and NO I don`t think Holley/Lunati bought him out, his problems were with the federal government and federal withholding taxes.. ...redvetracr

71coupe

Don't know if you've checked this yet, but make sure the dist is not being compressed down into the cam when you tighten the timing adjustment bolt. I don't know what the spec is, but I know you need a little play.

Fevre

I can give you first hand experience so hope this helps:

I have a Crane hyd roller cam with pressed on cast iron gear, ran it with my MSD dist with no dist gear change with no problems. I had problems with a bronze gear on a stock GM dist in my 89 formula, the gear got chewed through and the dist stop spinning. I changed that gear to a stock GM gear from another dist I have out of an 89 Firebird and after driving it a few times I pulled the dist and it shows signs of wear. Now I am working with a retro fitted LT1 intake that the previous owner set up including having to drill a dist hole, new LT1's have the Optispark so not dist, and it also has to have a base built up for the dist to sit on since the intake is low where the hole is drilled so I might have alignment issues.

But the stock MSD gear works fine with a cast iron pressed on gear on the Crane roller cams.

norvalwilhelm

You would think that the cam manufacturers would sell the proper distributor gear for their cam as an option, not let us struggle with this problem.
I went through 2 bronze gears before they told me to use the stock GM gear. Any of the .491 gears can be openned up for the .500 shaft. I use a .499 reamer and it takes only a minute. Polishing out with emery paper is the hard way and the hole can get tapered.
I just looked at a one of my old bronze gears and it is heavily worn on the bottom but looking from the top looks new.
This might just be the way they wear of the actual tooth contact is near the bottom.

Fevre

Another problem I am dealing, and I am sure many others are, is I only know what the presious owner told me about the set up so I have to investigate everything that goes wrong and learn as I go. I already found the gas lines leaking, unhardened washers under the rocker studs and there is some play in the rear end and now this cam fiascal.

No one said hot roddin' was easy. :jester

gkull

At least I'm not the only person to get screwed by comp cams. I don't trust or believe them.

I ordered a custom cam with a sleeved gear and they said no problem. Well what I got from the Brown truck is a non sleaved gear and an additional $80 for their at cost price of a Polyomer "Carbon fiber" dist gear.

I've never had problems with other cam vendors and I'm really all for Crane cams and their true small base circle cams. I've never had them BS or should I say outright lie like the people at Comp Cams.

For all we know, Maybe the actual cam gear is all cut wrong VETDRMS. Or even a few thousands off in placement on the cam length

My buddy couldn't get his new XE268 to slide all the way into his right out of the shop block. He called me up and I told him that he must have a cam align bore problem or the cam bearings were wrong. So he hauled it all back to the machine shop. It didn't occur to me that a new cam would be warped from end to end. He took the bad cam back down to Summit racing and got a replacement. But that doesn't pay for the headache and hauling a motor around. Now I'm not saying that it was 100% CC's problem. Maybe it sat on a big rack at Summit with weight on it for a year.


[Modified by gkull, 9:55 AM 4/6/2004]

redvetracr

I would think all cam manufacturers would use an identical gear on their cams so us idiots would have one LESS thing to complain about!! but then thats just me... of course that would also be one less trinket for them to sell.
...redvetracr :mad

Ironcross

http://www.pioneerautoinc.com can supply the distributor gear in both .500 or .491 as part of their performance line.
839013 is the .500
839014 is the .491
I am a distributor of their auto parts. :thumbs:

MotorHead

Aint' this nice look wht they told me: :confused:

Hello,
>
> I am buiding a 406ci SBC right now with your XR-280R (12-771) street roller
> and would like to know what distributor gear you recommmend with my MSD Pro Billet distributor ?

Their reply:

Wayne, you need to run a factory style cast iron distributor gear.
Thanks,Hadley


**And it just keeps getting better !

Hadley,
>
> Thanks for the quick response, so you are saying I will be OK with the gear
> that came on my MSD Pro Billet ?

His Response :

No, I would run new gear from a local parts store or our new carbon ultra-poly
gear. Part number 12140.
This gear is made from a high density carbon fiber polymer matrix
that will outlast a conventional bronze or steel gear.
Thanks,Hadley




[Modified by MotorHead, 1:09 PM 4/6/2004]