Timing chain install question.

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74RR

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I installed a new cam and timing chain set in my 360. When lining up the dots on the cam gear and crank gear should the #1 piston be at TDC? I haven't done this years and need a refresher. Thank you.
 
dot to dot will be #1 overlap , cam dot straight up will be #1 TDC either is correct
 
Yes. Lining the dots up with the crank gear at 12 and the cam gear at 6 actually times the engine at 180* out. You will need to either rotate the crank shaft one revolution, OR put the distributor in pointing to number 6 on the cap. I prefer to rotate the crank one revolution so as to have the distributor in correctly. Either way will work.

I am assuming from your question that you are not going to degree the camshaft. You should.
 
If you are going dot-to-dot, You can line the marks up on the workbench,using a straightedge, and slam the set on wherever it falls,so long as the sprocket teeth remain continuosly engaged .
 
So to be at TDC on the Comp stroke the dots should be at 12:00/12:00? Maybe I should get some help degreeing this cam in.
 
74RR said:
So to be at TDC on the Comp stroke the dots should be at 12:00/12:00? Maybe I should get some help degreeing this cam in.
Click to expand...

The piston is up either way. It's much easier to line up with dots to dot as you can see error.

All this amounts to is you turn the crank one turn, timeing mark to TDC, the thing is dod to dot. Turn it one turn, it's 12oclck, etc.
 
74RR said:
So to be at TDC on the Comp stroke the dots should be at 12:00/12:00? Maybe I should get some help degreeing this cam in.
Click to expand...

Yes. Remember this, the cam gear has twice as many teeth as the crank gear so the cam only rotates at 1/2 the speed of the crank. Therefore when you align it dot to dot and rotate the crankshaft 1 turn the cam dot will now be at 12 O'clock.

It is always a good idea to degree in a new cam/timing chain combo. You never know when you might get something defective. A few yrs. ago I degreed the cam in a 454 Chevy for a guy and found it was 16 degrees off due to a defective timing set. It would have been a miracle if it would have even ran. Degreeing' in the cam also makes sure your new cam is installed at the intended point to work the best.
 
As said its always a good idea to degree the cam. it's takes a fair amt of reading to catch on to its idiosynchrasies/how it is done but when you grasp it it'll have been worth it & it is pretty simple (once you get there). With it dot to dot (6/12 o'clock) both #1 and #6 pistons will be at/very very near TDC however only the #6 piston will be at compression/ready to fire because of the cam phasing not neccessarily the piston position so degree the cam if you want to go that far then turn the dampener a bit back CCW till the marks are at 15 BTDC then install the dist & turn the housing till the magnet is dead even with the reluctor tooth and you want the can on the pass side with room to be turned both ways & before that ideally you want to install/clock the intergear ANYWHERE so that with the dist installed the rotor is pointing rearward and slightly to the drivers side which maintains the OE factory firing order & helps prevent future mistakes. As you know the dist can be installed 180 out but when you are at 15 BTDC #6 compression just have the rotor rearward & slightly to drivers side then plug in the #6 plug wire at that rotor location then continue with the plug wire routing 1-8-4-3-6-5-7-2. this OE standardization lets the plug wires nestle as neatly as possible with the shortest lengths possible. make a mark on the dampener 2 & 7/32" CW from the OE TDC slit & have your dist man set it to that when it fires (new cam breakin I am assuming) & this is with vac adv capped for the breakin. read "breakin secrets" at www.mototuneusa.com. EDIT To ans your Q when the crank gear dot is at 12 o'clock (assuming a correctly stamped crank gear/correct keyway slot/degreeing required/highly recommended) then yes the piston (actually both #1/#6 pistons) will be at TDC with the crank keyway at ~1:30. MORE EDIT AJ's trick is neat/I love it! as it is much easier to line things up on the bench & you can actually set the dots at 12/12 o'clock (hard to do on the eng cuz the crank snout is in the way) then time the dist to #1 cuz that will make it easier to grasp what you are doing (rotor forward & slightly to pass side). just install both gears/chain on parallel/even so you dont bind the chain
 
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