Cam looks like its toast...whaddya think??

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4spdragtop

4spdragtop

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Stopped by dads today and he has started to take apart the 273 for new gaskets. A couple questions

1. We were checking the cam out and a few of the lobes looked iffy. Whats yer opinion, and if it needs replacing, what do you recommend for new cam and lifters??

2. The timing chain(single roller, steel teeth) has about 1/4 of deflection on one side(opposite side snug). Teeth on both gears look good. Normal?? 1st pic is straight edge resting against chain, 2nd pic straight edge pressed against chain, 3rd pic is straight edge pressed against chain showing the amt of deflection. Should we upgrade to a dbl roller??

Its a date code of 5/6/66 273 4 bbl.

Thanks
4spdragtop and dad
 

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honestly , to me, the cam looks shaky. if it were me ,i would put a new chain (timing set)on while it is open. it all looks really nice and clean. you might as well do it all while you are in there
 
hi I see some pitting on edge of cam lobes, means wear !!! should replace it.
chain looks to be normal change cam , might as well replace it too, just food for thought.
 
From what I see the cam looks OK. Do you have a better shot of suspect areas? I would put a new timing chain in it as long as I was that far into it. I'd spring for the double roller any time I replace a timing chain.
 
grimreaper said:
From what I see the cam looks OK..
Click to expand...

Boy, not from what I saw. The chain doesn't look all that bad to me IF this is a fairly low performance application, I'd leave the chain, unless you have extra money.

Do NOT replace just the chain. Replace a matched cam drive. NEVER put new chain on worn sprockets or vise versa.
 
grimreaper said:
From what I see the cam looks OK. Do you have a better shot of suspect areas? I would put a new timing chain in it as long as I was that far into it. I'd spring for the double roller any time I replace a timing chain.
Click to expand...

In the 2nd cam pic, you can see the wear on the furthest right lobe.... a few of them are similar. I agree with the chain/gears but dont wanna spend all of dads $$. Looks like cam/lifters are needed for sure. Any recommendations for cam/lifters?? Wanna go pretty much stock, but I might be able to sneak a bit of a lump in....LOL. We have the option of stock torque converter, or a 2000 stall one. Carb is a stock Carter I believe 4620SA(it think).

Thanks!
 
Wow Steve,IT does not look good to me !
Pitting is not normal for any camshaft lobe and is considered to be damage. It is usually caused by corrosion pitting and metal fatigue. Very common with low usage engines that are not driven much and sit a lot...
Your in it this far,I would pull the lifters to inspect and I bet ya they are dished.
I believe it is time for lifters,cam,and timing chain set.
Martin
 
TXDart said:
Wow Steve,IT does not look good to me !
Pitting is not normal for any camshaft lobe and is considered to be damage. It is usually caused by corrosion pitting and metal fatigue. Very common with low usage engines that are not driven much and sit a lot...
Your in it this far,I would pull the lifters to inspect and I bet ya they are dished.
I believe it is time for lifters,cam,and timing chain set.
Martin
Click to expand...


Thanks, Im gonna try and convince dad on timing chain and gears as well. He agrees with the cam/lifter swap. Recommendations on what to get?? I will do some checking, but looking for 1st hand experience.

Thanks!
 
Go Commando,
You need a 4 barrel though:
Lift Duration
Intake Exhaust Intake Exhaust
Commando: 0.425" 0.425" 248° 248°
 
TXDart said:
Go Commando,
You need a 4 barrel though:
Lift Duration
Intake Exhaust Intake Exhaust
Commando: 0.425" 0.425" 248° 248°
Click to expand...

It is a commando engine with 4bbl, the only thing different than stock is the pistons....lower compression on the current ones.
 
I really don't see any lobe wear and its hard to tell if that is pitting or just a light reflection difference.It does seem to be wearing oddly but as far as the lobes they look good from what I can see of them.Look to see if the geometry of the lobe is the same on both sides if it is flatened out on the lift side it is going down if not its really whether you want to spend the money to replace the whole deal and thats what I would do if your going to change a couple parts do them all,lifters,cam and chain set and might as well throw some cam bearing in it also.But like I said you can get more miles out of what I see here if you decide to.
 
I see lobe wear. I don't have any idea what the rest of you are looking at.

6y2uqa.jpg
 
67Dart273 said:
I see lobe wear. I don't have any idea what the rest of you are looking at.

6y2uqa.jpg
Click to expand...
To me and from what I can tell from these pictures which may look different at other angles that looks like contact wear around the bottom of the lobe.I am looking more for the flattening of the lobe side as being wore out.more of a side shot picture would really help with determining what is going on in there.
 
That cam is shot. Call Comp Cams, and give them all the info on your car.
Let them help you chose a cam. Look for something in their XE Extreme Energy line.
 
4spdragtop said:
Thanks, Im gonna try and convince dad on timing chain and gears as well. He agrees with the cam/lifter swap. Recommendations on what to get?? I will do some checking, but looking for 1st hand experience.

Thanks!
Click to expand...

My first 68 cuda 318 car had original chain with 84k miles on it. Replaced the lifters and new double roller chain, and it got 2 MPG improvement city driving. It will pay for itself in economy alone (especially at these prices). That was back when gas was a buck a gallon, air was clean, and sex was dirty... Oh, the good ol days...

Talk him into replacing the chain with a good double roller.
 
Alright, we're goin Commando... (or Brazilian) Gigity, gigity...

[ame="http://www.youtube.com/watch?v=UJGksvSzXzs"]Family Guy - Tear Up My Carpet - YouTube[/ame]
 
The little Comp 268 solid would be great in it.
 
Replace both the cam and timing set.
You'll never regret it.
Phone comp cams for a recommendation, that's what i would do.
We're not talking a lot of money overall here.
 
mopar410 said:
To me and from what I can tell from these pictures which may look different at other angles that looks like contact wear around the bottom of the lobe.I am looking more for the flattening of the lobe side as being wore out.more of a side shot picture would really help with determining what is going on in there.
Click to expand...

You need to look again, my friend. First, lobes don't normally wear "at the bottom"

In the photo, the lifter at top left is UP on the top of the lobe. That roughness you see IS the top of the lobe

The center lifter is DOWN (valve closed) and the roughness you see at the top of the photo IS the top of that lobe, which is badly worn

The same is true of the right hand lifter. It is down/ closed, and the roughness is on the "ramp" near the top of the lobe

That cam is toast, plain and simple.

6y2uqa.jpg
 
Dad and I think its toast too, there is lots of decayed edges on several lobes. Not gonna take a chance on it. Any reason why the heads have to come off if we get the machine shop to replace the cam bearings?
I will chk out Comp cams.

Thanks everyone, keep the cam recommendations coming too
 
I agree, the cam is just a few miles from the lobes starting to go flat. In the past when I changed cams and lifters, I always put in new timing components because to me, it was cheap insurance angain any valve train problems. If you machine shop is good, they can change to cam bearings without have the engine totally apart. They just need to make sure all of the old bearing material makes it's way out. JMO
 
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