Slant Six Forum
https://slantsix.org/forum/

Cam stop
https://slantsix.org/forum/viewtopic.php?t=6542		 Page 1 of 1
Author:  Jopapa [ Tue Aug 12, 2003 11:24 pm ]
Post subject:  Cam stop
If we end up pulling the engine, one of the jobs we'll (I'll) be doing is pulling the timing cover and inspecting the chain and cogs. I figure while it's off it'd be a wise move to install a cam stop. Doug I saw the pic in your oil pump gear article, and it looked like you used an adjuster bolt from a rocker arm inside of another bolt that was brazed to the cover. I also was wondering that, since the cam spins against it, maybe some sort of nut with a ball bearing in the end (like the tip of a ball point pen kinda) would be a good idea?

Are there any tips you can give me on doing this? Is it necessary to make it adjustable? Anyone have a spare timing cover I can relieve you of if I screw it up? :wink:
Author:  Red [ Wed Aug 13, 2003 9:45 am ]
Post subject:  cam stops
Jo...

Here is a direct quote from Doc (my edit in brackets) to a question I posted some time ago on the old forum. I just happened to print it out, but can't access it in the archives anymore:

-------------------------------------------------------------------------------------
"The ball-screw does end up in the "X" [stamped relief on T-cover] but you but you need to find dead center to the cam bolt hole.

The way I do that is by using a piece of 7/16-14 threaded rod with a point machined onto the end of it. I install that into the end of the cam and install the cover over it. Now it is a simple matter of pushing the cam forward and "center punching" the backside of the cover, the punch mark it leaves is the place to drill your hole. You must also select a grade 8 bolt and grind the face of the head smooth.
DD"
-------------------------------------------------------------------------------------

Hope that gets you started. I'm sure Doc will add any additional info he thinks would be helpful next time he "breezes through town".


---Red
Author:  Doc [ Wed Aug 13, 2003 10:19 am ]
Post subject:  Re: cam stops
Quote:
Jo...

Here is a direct quote from Doc (my edit in brackets) to a question I posted some time ago on the old forum. I just happened to print it out, but can't access it in the archives anymore:

---------------------------------------------------------------------
"The ball-screw does end up in the "X" [stamped relief on T-cover] but you but you need to find dead center to the cam bolt hole.

The way I do that is by using a piece of 7/16-14 threaded rod with a point machined onto the end of it. I install that into the end of the cam and install the cover over it. Now it is a simple matter of pushing the cam forward and "center punching" the backside of the cover, the punch mark it leaves is the place to drill your hole. You must also select a grade 8 bolt and grind the face of the head smooth.
DD"
------------------------------------------------------------------------

Hope that gets you started. I'm sure Doc will add any additional info he thinks would be helpful next time he "breezes through town".
---Red
A search using ' cam and button ' came up with some info., here is the detail on how I add a cam stop to a SL6 timing cover:

-------------------------------------------------------------------------

A cam stop is a good up-grade and easy to do if you have access to a welder.
I have a special center punch which screws into the cam's tapped front hole and then I install the cover and push the cam forward to create a centered punch mark to drill by.

I drill a 1/4 inch hole and use it to screw down a 3/8 - 24 unf nut. I weld on the nut, you can add a large flat washer to the backside to help stiffen the area. I run a tap through the welded assembly just to clean-up the thread, then use rocker arm "ball screw" and lock nut as the cam stop. I also grind smooth the cam's top timing gear bolt head so the contact area is smooth. ARP also sell a nice bolt with a smooth radius in the head which is really cool for a race application.
http://www.dutra.org/doug/draft-webpage ... m-stop.htm

Once everything is installed, you can adjust the stop so there is .005 of clearance and lock it down. (do this before the lifters go in or the oil pan goes on, so you can reach in and move the cam back and forth easily, to feel the clearance)
DD
Image

Image
Author:  Dennis Weaver [ Wed Aug 13, 2003 10:34 am ]
Post subject: 
Jopapa, I just wanted to point something out. I'm not sure if you are wanting to hop up this six so your girlfriend can race or what. All of the mods that Doc and the other racers do to their /6's are well thought out and executed and are done to help their motors "hang" in the most extreme of circumstances. Probably most of the things they do are an improvement to the stock motor even in a mild-duty application. That said, the slant 6 is notoriously unkillable and well designed, even in bone stock form. Yes, there were compromises in the interest of mass production, but I guess where I'm going with this is, do you really need to do some of the modifications that you are considering for a car that your girlfriend will be lazily tooling around in? Of course that choice is up to you (well her, really). The stock /6, or even a mildly warmed up one if the two of you choose that option, will perform endlessly with the care and maintenance that I'm sure you're capable of without trick oiling and cam buttons and the like. Why don't you save up and build your own race car and apply the technology to it?

Ok, now point out the conflict between this advice and my signature blurb... :wink:

"DW"
Author:  Jopapa [ Thu Aug 14, 2003 9:25 pm ]
Post subject: 
Quote:
Jopapa, I just wanted to point something out. I'm not sure if you are wanting to hop up this six so your girlfriend can race or what. All of the mods that Doc and the other racers do to their /6's are well thought out and executed and are done to help their motors "hang" in the most extreme of circumstances. Probably most of the things they do are an improvement to the stock motor even in a mild-duty application. That said, the slant 6 is notoriously unkillable and well designed, even in bone stock form. Yes, there were compromises in the interest of mass production, but I guess where I'm going with this is, do you really need to do some of the modifications that you are considering for a car that your girlfriend will be lazily tooling around in? Of course that choice is up to you (well her, really). The stock /6, or even a mildly warmed up one if the two of you choose that option, will perform endlessly with the care and maintenance that I'm sure you're capable of without trick oiling and cam buttons and the like. Why don't you save up and build your own race car and apply the technology to it?
Well my way of thinking is that if little mods like these can help the longevity of a racing engine, they'd help the longevity of a stock daily driver even moreso. Like with Doug's lifter oiling trick and the little oil jet spraying on the gears (though I doubt I'll do that one, given the work it takes).
Page 1 of 1 All times are UTC-08:00
Powered by phpBB® Forum Software © phpBB Limited
https://www.phpbb.com/