Cam degree..

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j par

j par

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I've mentioned this on my restoration thread but I'd like to try and get a little action here. It's saying 108 on the intake with a 112 separation center line and a 116 on the exhaust. So I'm shooting for this 108 and I'm getting 110 to110.5..
I'm thinking of just letting it ride as I'm under the impression that I may lose a couple degrees just with the timing chain stretching?.. I do have a multi-key lower gear to advance and retard but I think this may be just pushing the limits of what's really needed..
Help and opinions welcome thank you for your advice..
 
It will be fine. I know it is for a truck, but with 408 cubes, 224 @ .050. on a 112, the cam will be tame.
 
That'll be 2 to 2.5 degrees retarded. If it was ME and I wanted to install it so as to take into consideration for chain stretch, I'd install it at 106 instead of 108. That way, by the time the chain has broken in, it'll be closer to the 108, instead of around 112 or so from you leaving it 2 or so degrees retarded.
 
RustyRatRod said:
That'll be 2 to 2.5 degrees retarded. If it was ME and I wanted to install it so as to take into consideration for chain stretch, I'd install it at 106 instead of 108. That way, by the time the chain has broken in, it'll be closer to the 108, instead of around 112 or so from you leaving it 2 or so degrees retarded.
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Why does that make sense.. damn you!
 
I'd echo RRR, I'd rather be advanced than retarded.. Especially in a pulling/low rev application.
 
RustyRatRod said:
That'll be 2 to 2.5 degrees retarded. If it was ME and I wanted to install it so as to take into consideration for chain stretch, I'd install it at 106 instead of 108. That way, by the time the chain has broken in, it'll be closer to the 108, instead of around 112 or so from you leaving it 2 or so degrees retarded.
Click to expand...
Okay back inside now I had my thinking reversed I believe... I had to get out there and start cracking on this and figure out all my problems... I know Ken at Oregon cam offered advice if I called him but of course I get to do this on the weekend. As well as the owner of the machine shop where the block was done...
Of course I have no oil slinger so I'll be sourcing one of those from someone local. I don't know why I can't find the one that I'm sure I have.
And wouldn't you know it the push rods are too short..:BangHead:...
I have plenty of parts to clean for now so I'll just continue there.. I did get the passenger side head installed but due to the light of the news timing situation I'll probably just hold off on the passenger side so I can check the degree again...
PXL_20211016_221854062.jpg
 
j par said:
Okay back inside now I had my thinking reversed I believe... I had to get out there and start cracking on this and figure out all my problems... I know Ken at Oregon cam offered advice if I called him but of course I get to do this on the weekend. As well as the owner of the machine shop where the block was done...
Of course I have no oil slinger so I'll be sourcing one of those from someone local. I don't know why I can't find the one that I'm sure I have.
And wouldn't you know it the push rods are too short..:BangHead:...
I have plenty of parts to clean for now so I'll just continue there.. I did get the passenger side head installed but due to the light of the news timing situation I'll probably just hold off on the passenger side so I can check the degree again...View attachment 1715806458
Click to expand...
Screw the adjuster on down until you can adjust the valves and see how many threads are showing on the pushrod side.
 
I'm going to take a swing at some longer push rods from Summit.... If they don't work I'll send them back and just bite the bullet and dial up Smith Brothers..
 
If my duster wasn't in storage I'd probably just pull a valve cover and pull a push rod and see..
 
RustyRatRod said:
Yeah, my one eye works very well. Just do it and get a picture.
Click to expand...
Well I'm fully discouraged for today and probably not going back to the garage. But I do have two more days to work on this and tomorrow I'll start out giving that cam four more degrees of advance and start cleaning parts... Excuse the pun but just eyeballing it I would say I would use up all the adjuster threads sticking out the top to make up the distance at the bottom. Again in the ballpark of a quarter to a half inch....
 
j par said:
Well I'm fully discouraged for today and probably not going back to the garage. But I do have two more days to work on this and tomorrow I'll start out giving that cam four more degrees of advance and start cleaning parts... Excuse the pun but just eyeballing it I would say I would use up all the adjuster threads sticking out the top to make up the distance at the bottom. Again in the ballpark of a quarter to a half inch....
Click to expand...
You can go three or four full threads exposed from the under side of the rocker and be acceptable. So stop whining and screw the adjuster down some get a picture and let's see it.
 
RustyRatRod said:
You can go three or four full threads exposed from the under side of the rocker and be acceptable. So stop whining and screw the adjuster down some get a picture and let's see it.
Click to expand...
PXL_20211016_232945433.jpg

There you go boss.. I ain't running it that far away... Now can I go inside and wash my hands please..
PXL_20211016_232953918.jpg
 
I think the point of screwing the adjuster down was so you could count thd threads under the rocker, count the threads you want removed, calculate threads per inch, and it will tell you how much longer your pushrods have to be. Looks like at least a +.250.
 
33IMP said:
I think the point of screwing the adjuster down was so you could count thd threads under the rocker, count the threads you want removed, calculate threads per inch, and it will tell you how much longer your pushrods have to be. Looks like at least a +.250.
Click to expand...
Actually I think our one-eyed wizard LOL thought that I could use what I have. I could see that that wasn't going to happen but in order to not have him start calling me names I went ahead and got my hands dirty again...
 
33IMP said:
I think the point of screwing the adjuster down was so you could count thd threads under the rocker, count the threads you want removed, calculate threads per inch, and it will tell you how much longer your pushrods have to be. Looks like at least a +.250.
Click to expand...
Yes.....you know me. I always take the long way around the barn.
 
j par said:
Actually I think our one-eyed wizard LOL thought that I could use what I have. I could see that that wasn't going to happen but in order to not have him start calling me names I went ahead and got my hands dirty again...
Click to expand...
hush up dummy.
 
3/8 longer push rod ? looks like 3/8 to me.
 
Well I'm not sure about is if the push rods at least the ones on Summit are measured from the contact point of the inside of the cup to the end of the rod or from the end of the rod to the end of the rod??..
 
j par said:
I've mentioned this on my restoration thread but I'd like to try and get a little action here. It's saying 108 on the intake with a 112 separation center line and a 116 on the exhaust. So I'm shooting for this 108 and I'm getting 110 to110.5..
I'm thinking of just letting it ride as I'm under the impression that I may lose a couple degrees just with the timing chain stretching?.. I do have a multi-key lower gear to advance and retard but I think this may be just pushing the limits of what's really needed..
Help and opinions welcome thank you for your advice..
Click to expand...
Use timing gears, they dont stretch.
I have never installed a cam retarded, you will lose cylinder pressure.
Maybe that's what you want?
 
Advance it, if in doubt advance the cam, unless you are class racing and shifting at 8700rpm. Just saying.
 
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