400 cam timing mark question

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gdbuick

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Hello
I have a 400 engine we picked up tearing it apart trying to teach my son the four stroke operation. I worked on Buick engines for 27 years so just learning the Mopar engines myself. I’m used to the timing dots being at 6 o’clock for cam with the crank dot at noon and distributor at #one plug. In the picture you can see my finger pointing to what looks to be the timing mark at noon for the cam, is this a dodge thing ? With Both dots at noon the camshaft seems to be in the proper order to fire number one. Unless I’m not looking at the correct cam timing mark as there is the Chrysler symbol at 6 O’clock? I have two shop manuals and both just say to align the marks but no specifics on clocking.
Thanks
 
Interesting markings. "Dot to dot" puts #6 cyl at tdc compression. Both dots at 12 put #1 cyl tdc compression
 
Yes, that is normal for a Mopar. It confuses a lot of people who put the distributor in 180 out.
 
It is normal for every American V8, all of GM and Buick included. Every tech manual ever written says to line them up crank at 12 and cam at 6. What they always leave out is that this is actually 180 out. The reason for this is simplicity. It's easier to line the dots up together than it is with the cam at 12. You just need to remember to either rotate the engine so both are at 12 when done, or time it up on #6.
 
When I was a hellofalot younger, I lost a bet on this concerning a SB Chev, which (at least some of which) are this same way. About that same time, I had helped a buddy install a cam in a 440. I had dropped the dist in when the cam was "lined up" and could NOT understand, later, why I got it 180 out.
 
RustyRatRod said:
It is normal for every American V8, all of GM and Buick included. Every tech manual ever written says to line them up crank at 12 and cam at 6. What they always leave out is that this is actually 180 out. The reason for this is simplicity. It's easier to line the dots up together than it is with the cam at 12. You just need to remember to either rotate the engine so both are at 12 when done, or time it up on #6.
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Ok thank you it's not a GM versus Dodge thing. My mistake on thinking Buicks were different I just forgot all the details as I don't do this everyday. I looked back at a Buick site for a BB 455 motor which I copied below explaining the confusion with the dots and distributor installation incase someone else gets tripped up or confused.

"If the timing chain is installed, "TDC" could be TDC-exhaust, or TDC-compression. When the "dots" are close together--crank dot "Up" and cam dot "Down", (the way most folks do the job!) the engine is at TDC-exhaust, which means you'll have to drop the distributor in with the rotor aligned for firing #6, NOT #1."
If the crank and the cam gear dots are both "UP", it's way harder to verify that they're truly aligned--but that's where they'll need to be to drop the distributor in with alignment for firing #1."

Off to teach my son now.... Thanks Greg
 
You can time the cam with the dots close together, then rotate the crank 1 turn to put #1 at TDC FIRING, then install dist to #1. That's the easiest way to do it.
 
Welcome , My best , sbc expert , swears that "dot to dot" is #1 tdc on compression . So you can understand when my motor wouldn't start . BTW , my Mrs. is from West Roxbury and I'm from Hanover . Moved to God's country 10 years ago . Love it here , stay safe , Tom
 
gdbuick said:
Ok thank you it's not a GM versus Dodge thing. My mistake on thinking Buicks were different I just forgot all the details as I don't do this everyday. I looked back at a Buick site for a BB 455 motor which I copied below explaining the confusion with the dots and distributor installation incase someone else gets tripped up or confused.

"If the timing chain is installed, "TDC" could be TDC-exhaust, or TDC-compression. When the "dots" are close together--crank dot "Up" and cam dot "Down", (the way most folks do the job!) the engine is at TDC-exhaust, which means you'll have to drop the distributor in with the rotor aligned for firing #6, NOT #1."
If the crank and the cam gear dots are both "UP", it's way harder to verify that they're truly aligned--but that's where they'll need to be to drop the distributor in with alignment for firing #1."

Off to teach my son now.... Thanks Greg
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It's really not harder to identify TDC at all the "correct" way. All you need is a grammar school 6" ruler and you can use it as a straight edge to assure the dots are properly aligned. Been doing it that way a long time and it works well. Of course make sure to use the degree wheel, too.
 
383Scampman said:
Welcome , My best , sbc expert , swears that "dot to dot" is #1 tdc on compression . So you can understand when my motor wouldn't start . BTW , my Mrs. is from West Roxbury and I'm from Hanover . Moved to God's country 10 years ago . Love it here , stay safe , Tom
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That's funny on the dots but not when your engine didn't start I'm sure.

I grew up in Brockton for 27 years and I'm now in Bellingham, Mass so we are local to you. I just learned last weekend while picking up a 383 core in Weymouth about Camco racing engine builder in Quincy Mass. Met the owner Dana Hard and got a shop tour. Very impressive shop and multiple engines from all makes in there being assembled approx. 25 engines in there. I will be using him down the road.
Greg
 
Oh and I love me some Buick. Always wanted to do a 430 Apollo. I've said for years that has Buick made their version of an F body, that the muscle car era would have had to be rewritten. The Buick big block is be FAR the lightest big block out of the bunch and they're torque monsters.
 
Hi Greg , please look up on the net : Massachusetts Cruisers Auto Club .com . I am a long time member and past president . there are quite a few members from the Bellingham area . Best club on the planet . They sponsor the cruise at BassPro shop , family friendly group . I have known Dana forever . Used to go to his shop often , the Spindles Auto Club clubhouse is right behind his shop. You found a 400 in Weymouth ? Wow, I've been looking for a 400 for 2 years . Good for you . Anyway, we are here to help , keep us informed . Later, Tom
 
383Scampman said:
Hi Greg , please look up on the net : Massachusetts Cruisers Auto Club .com . I am a long time member and past president . there are quite a few members from the Bellingham area . Best club on the planet . They sponsor the cruise at BassPro shop , family friendly group . I have known Dana forever . Used to go to his shop often , the Spindles Auto Club clubhouse is right behind his shop. You found a 400 in Weymouth ? Wow, I've been looking for a 400 for 2 years . Good for you . Anyway, we are here to help , keep us informed . Later, Tom
Click to expand...

Hello Tom,
I will look into that. I have heard about the cruisers but maybe it’s time to get my son/me into a club. Interesting on the club behind Dana’s shop.
I picked up a 383 block/crank in Weymouth but this post is a 400 block on the stand that I recently picked up from down the cape about three months ago. The same guy also had a fully assembled 400 never started no details on build as he inherited it. I took pictures of it and maybe able to dig up his information. Pm me if interested.


Greg
 
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