So here is the deal, I'm doing a cam swap on a 1971 402 BB. Timing marks where brought to TDC, verified the rotor was pointing to #1 cylinder. Now I pull off the timing cover and the "dot" on the cam gear is pointing at 12 o'clock, same as the crankshaft gear?? If I rotate another 180 degree's then everything lines up as expected but now the rotor is pointing to #6 cylinder.The car ran perfect before so I know the cam/ignition timing is correct. Also the dowel for the camshaft is at the 9 o'clock position versus the normal 3 o'clock. So do I go ahead and install the new camshaft with the same reference's as the original?

The cam gear mark should be at 6:00 o'clock (not 12:00) and the crankshaft gear mark at 12:00 o'clock with the #1 piston at TDC and the rotor pointing toward #1 cylinder like this------> http://www.chevyhiperformance.com/techarticles/148_0306_chevrolet_406_big_block_torque/photo_07.html

If I where to time it as per the article and I know that is the norm for almost all Chevy's, I would be out 180 degrees on the firing order. Yes I know simply switch the wires on the cap and your good to go. Now both heads are off the vehicle and before I removed the rocker arms I checked and both valves where closed on #1 cylinder. What I'm asking has anyone ever run into this before where both the cam and crank sprockets have the dots both at the 12 o'clock position when your at TDC on #1 cylinder.

Were both valves closed right after the the exhaust valve closed? or right after the intake closed?
Make sure they were both closed right after the ex. valve closes on the #1 cylinder.

hi, my name is mark, what you are seeing is normal for the chevy. what you want to do is put the crank dot on top and the cam dot on bottom. line them up and install the timing gear. this puts the #1 piston top dead center exhaust stroke. rotate the engine one full turn, now both dots are on top. and #1 piston is top dead center, compression stroke. install the intake and distributor and point the rotor towards #1 on the cap. this usually starts up the engine with the timing slightly retarted. usually i advance the dist. slightly.

Here's what I do.

I match the dots on the cam and crank gears just as you see them in the Chevy High Perf mag article linked above.

Without rotating the engine any, I then install the distributor so that the rotor button (once it drops in all the way) is pointing at number one cylinder and the vacuum advance diaphram is pointing about halfway between #2 cylinder and straight ahead. You may need to rotate the oil pump drive a little with a screwdriver to get the distrib to drop in all th eway. Once it's seated, install the distrib hold-down and bolt leaving it loose enough to be able to turn (advance/retard) the distrib a little.

I then button everything up. Install the distrib cap. Then install my plug wires, starting with #1 and proceding clockwise (looking down on the distrib cap) using the 1-8-4-3-6-5-7-2 firing order sequence.

If the engine's out of the car, I'll wait till it's back in before installing the distributor just to keep from breaking anything. Just be careful not to turn the crank until the distributor's seated all the way.

Technically speaking, you can align both cam and crank gears in their 12:00 positions and get the same result, but it's a lot harder that way to be sure you aren't one tooth off on your cam alignment.

Hope it helps.

I installed the cam exactly the way Mark suggested as it made sense in this case. After everything was back together it started right up on the first crank-Perfect
Thank You all for your help and thought you might like to see the end result
.Click here for picture (http://elcaminocentral.com/gallery-photo_SS396-16_G.html)

Nice looking Elky! Can you post a pic of the engine to heater box clearance? I considered going with a 68-70 Big Block drivetrain...the best of both worlds, a 5th Gen and a true factory musclecar drivetrain.

It's very difficult in a picture to show the actual clearance. With these valve covers the tightest spot is 1/4"-the top rear corner of the valve cover to the heater case. The clearance gets greater the closer you get to the head. Bottom line is it fits but not the easiest to work on.When installing the cylinder heads with the block in the car, you must insert the rear most head bolt in the head before setting it in place otherwise you won't be able to install the bolt. Also very difficult to torque these bolts-limited space!!

Though partial to Alum headded BBC's myself, I do declare that's a sexy looking install. Very clean. Great job. Those manifolds look clean enough to eat off of. POR? It really looks nice. Glad the cam upgrade worked out well for you. 402 with 450 horses? That babe oughta really fly when it's time to steam the ricers.

Beautiful engine and engine bay! It's easy to tell that you took alot of time to do everything right.

Thanks everyone. Here is the picture that shows the clearance between the valve cover and heater box. There is room for the plug wires and that's about it
Heater box clearance picture (http://elcaminocentral.com/gallery-photo_SS396-5e.html)