fattest cam in a 340?

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Hyperballsmcgee said:
I think I was misunderstood. I have a mark, as it was highlighted with orange paint and still couldn't be seen by myself or another member here with the timing light.

honestly, I like the cam I have, It just isnt degreed correctly and I want to know the specs. I just figured starting all over with a new cam would be easier.
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If you have not disassembled the front end of the engine down to the timing chain and put a degree wheel on it and checked it you cannot say the cam isn't degreed correctly. IMO what your doing is confusing cam timing with ignition timing because you can't see the timing mark. Not seeing the timing mark is possibly due to a slipped outer ring on the balancer, the wrong balancer is installed, or the wrong timing cover is installed. Has nothing whatsoever to do with the cam timing. First thing I'd do is check the balancer over real good for a slipped outer ring. If it's ok get a top dead center indicator and figure out where TDC really is on the balancer. Then you can set your timing. If you don't figure this out no cam will ever run right.
 
take your valve cover off on #1 cyl bank, rotate clockwise until #1 intake valve is just closing ,STOP look at damper and find timing mark,.measure from mark to zero on timing tab. record measurement.continue rotating clockwise until intake valve is just closed,
again measure from mark to tab, note if it is before or after 0 mark.
let me know what you find then I will help you with the next step. good luck
 
Agreed here and to piggyback and help you out, here is an example of my old cam and the numbers stamped on it. My numbers were on the backside of the cam so I guess it depends on the cam company. This was a Schneider racing cam. You should see something similar on the snout. I love showing pictures to help, so all you have to do is ask. We are all trying to help you out so please listen to all the advice and don't take it personal as we have all been in your shoes at some point.

65Val said:
Yes, but you'll have to remove, at least, the timing cover and cam timing gear to see the end of the camshaft. There should be some numbers there...a grind number and (possibly)manufacturer...then Google that and find the cam (spec) card (hopefully)
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RustyRatRod and I talked privately and got things worked out, like I said, I'm an 18 year old college kid. this is my first mopar, my first v8, my first real hot rod. I'm here to learn, in hindsight, he did kinda help me. I hate when I'm at a meet or something and someone says something completely wrong thinking it's right and I guess he does too. I think it's best for all of us this thread just comes to a close.
 
No hard feelins. I was the biggest goof of a kid learnin all about this stuff. If I can keep it from happenin to somebody else, it's all well and good. lol
 
No reason to close it IMO. I did and said a lot of the same things when I was young and learning. We're here to help if we can.
 
Yeah we need this open. This is gonna be a good thread.
 
well in the spirit of keeping this thread alive, imagine this is your motor: you buy it, give it some tune up stuff; oil, plugs, wires, cap&rotor, ignition box, etc.

you go to hit it with the timing light and you see nothing.

you look on the balancer and clearly see a mark on it.

why would you not be able to see the mark, what do you do about it?

all the info you have is that it has some sort of aftermarket cam in it.
 
The first thing I would is paint the mark with white paint and try it again. If I still could not see it, I would find top dead center and see where the mark is and go from there. Do that and report back and we can continue to help.
 
ive got 10 bucks sayen your ballencer has slipped man! my 72 cast crank 340 did the same thing. execpt i knew i set it @ 12 btdc & just checken stuff out after another intake swap & it said 3 btdc. lknew dam well that wasnt rite. sent it to damper dr. got er fixed & presto right where i left it @ 12 deg. also it should have a external ballance damper for 72-73 340 only man.
 
Like mentioned a bunch, put at top dead center, mark balancer and see what happens when you time it. Get a piston stop, degree wheel, timing tape and do that properly, don't eyeball it. Go to YouTube and type in "using a piston stop to find TDC", lots of results come up to show you how. Definitely possible the balancer could have slipped, this will confirm that.

I had a 360 years ago that I put a comp cam in that had .525" lift, I think it was a 308H, maybe. I had stock everything for heads and valve train, I would wind it out to over 6500rpm often, not sure how it pulled to that with stock springs. Only other major changes was 4000 converter and 4.56 gears. Was a fun light to light car 20 yrs ago. Just some reference for you on size I've seen work with nothing done to guides etc.

Cheers
 
get yourself an engine book and read it! my dad got me one when I was 12, then he showed me how to tune without all the fancy tools.
 
Simple question, are you un-hooking the vacuum line to the distributor when checking for a timing mark?
 
alright this is where things go south. my distributor has no vacuum advance hooked up. at part throttle, the more vacuum that's applied, the more it stumbles. it runs best without it hooked up when compared to how it acts with one.
 
Leave the vacuum advance plugged off for now, least of your worries. It's there to help with part throttle mileage. You get TDC figured out and a mark on your balancer yet?
 
If it stumbles more with vacuum hooked up, I'm going to ponder aloud it may be too far advanced to see on the balancer...as mentioned above-find tdc, make or buy a timing tape, install it, and restart your tuning...
 
the guy I work for has been certified since the late fifties early sixties and had his own shop since 1971, also runs a whole other mess of shops here in town, he said, if I remember correctly, something (can't recall name of part) in there was loose and might be mo of around in there.
 
You've already covered the one that messed with me the most back in the day, a cracked distributor cap.

LJ67barracuda340 said:
could have a pre '71 damper on it. see which side the mark is at TDC.
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Actually, its more of a mismatch between the balancer and the front cover. 64-68 LA engines used a tab as a timing mark. 69-70 had the marks cast into the front cover. In 1971, the water pump was redesigned requiring the timing marks to be moved from the passenger side to the driver's side of the engine. If a pre-71 front cover and a post-71 balancer or a pre-71 balancer and a post-71 front cover are used in combination, the timing mark will be 90º off.

Another possibility is that the timing chain has slipped. The OEM, and several aftermarket, timing chain sets use plastic teeth in the camshaft gear. Like all plastic, it gets brittle and after a while a tooth will chip out. Since you're going to pull the cam anyway, think about using an all metal double row timing set when you go to button it back up.

How to find TDC without taking the engine apart, assuming the cam is correctly timed. It's not exact, but it can do until the timing set can be accessed. Remove the valve cover over the #1 cylinder. Remove spark plugs. (Actually only need to remove #1, but pulling more makes it easier to rotate the crank.) Cut a straight piece of coat hanger wire about 1½' long. Put wire through spark plug hole until contact with the piston is made. You may need to bend the wire so it will rise and fall freely within the cylinder. Rotate the crank until it pushes the wire to its highest point and both valves for #1 cylinder are closed. If the wire is up but both valves aren't closed, another full rotation is needed. Both valves are closed when the rocker arms are loose against the valve stem.
 
sorry guys, been busy with work and school lately and havent had much time do any work on the plymouth. i did hit it with 2 timing lights, one is an adjustable sunpro light, i have videos, will upload later.
im gonna say the balancer slipped, according to the timing light im 40 degrees advanced on initial timing...
 
Sure sounds like the balancer may have slipped. Word to the wise. Throw that dial back timing light in the ditch. They are worthless. Too many variables. What if the knob is not on quite right? Them little degree stickers ain't hardly ever in the same position. Just too much room for error. Unless it's a computerized, digital light, chunk it. A good old standard non dial back light is your friend here. But at least that dial back light did possibly show you that the balancer is slipped, so it did serve that purpose. I would just not try to set timing with it. JMO
 
I have another very basic light. it's just got your hot and ground wire, plug wire clamp, and a power button. also couldn't see the mark.

how do I correct this? just get a new balancer or can it be fixed?
 
The answer for what you need to do is in this thread MULTIPLE times...
 
Even if the balancer slipped you should be able to find TDC see where the timing line is(is it set to O degrees,it should be).If not mark it with a good visible marker.Set the timing from there.As for seeing it with a standard gun unless I'm forgetting something,you can't.340's like about 18 degrees initial timing which is way around from the standard marks and unseen.A good digital dial back gun or timing tape is the best way but you can find TDC and put a separate color mark at the 10 degree mark on the lower side of 0.Start it up and see if that mark is hitting around8-10 degrees on the upper side of 0 which would be 18-20 degrees initial.
 
BTW I have a unknown cam also.I got the numbers off it and can not find any info on it and it is a mopar purple cam,which should be fairly documented.So getting to the numbers may not help you out.
 
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