New cam and TDC timing 400 big block

flamesoldier

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I have a 400 big block and I am doing a hughes whiplash cam. I just stabbed the cam in and i am ready to set initial sprocket timing. I installed cam and crank sprocket “dot to dot” with the cam dot pointing down and the crank dot pointing up all at 0 degrees and top dead center. My main question is i have seen many people on youtube etc do this same practice but dont say to turn motor over after they are dot to dot to have both dots point at 12 oclock because dot to dot is 180 degrees wrong and the car wont start unless the motor is turned to the 12 oclock orientation. Is this accurate? After installing dot to dot rotate motor so that the cam and crankshaft are at 12 oclock?
 

Gunner1

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I'm on my first RB motor but every Chevy V8 I have ever done is that way. Dot to dot is tdc #6
 

Black_Sheep

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The cam rotates 1 time for every 2 crankshaft revolutions. If you set it dot to dot then rotate the crank 1 complete revolution, the cam will make 1/2 revolution and the dot will be on top.
 

Beekeeper

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Dot to dot is firing stroke for number 6 so yes dots at 12 are #1 firing stroke.
 

beanhead

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The guys got it. "Dot to dot" (cam sprocket [email protected]:00) is for degreeing the camshaft. Crank@ 12 and cam sprocket @12:00 is for installing the distributor.
 
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RemCharger

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Google up 4 stroke internal combustion engine it will all be crystal clear
 

flamesoldier

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The guys got it. "Dot to dot" (cam sprocket [email protected]:00) is for degreeing the camshaft. Crank@ 6 and cam sprocket @12:00 is for installing the distributor.
Yes exactly what i was looking for thank you. Thats what im going to do. Dot to dot degree cam then set dots to 12 oclock for distributor thank you for helping
 

RemCharger

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Yeah im sure i will find the answer for the timing for this exact motor that way i get being funny but you sir are just an asshole!

Didn't mean it that way , more about arming ones self with information.
But if you're in a pinch you can look at the #1 lifters through the distributor hole at TDC. Move the crank a bit, if the lifters move you're opposite of firing on #1.
If they don't move, you're at TDC firing #1.
 

beanhead

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Yeah I didn't think Rem was being snarky, just that you can find these neat animated clips of what the valves are doing during the four strokes which helps gain an understanding if you're not as familiar.
You wouldn't believe how many people will wrongly tell you "oh pingy-pingy from too much cylinder pressure? Just put in a cam with more overlap!"

Yes exactly what i was looking for thank you. Thats what im going to do. Dot to dot degree cam then set dots to 12 oclock for distributor thank you for helping
Great description Simple and to the point
I corrected my type-O!
Should have read "crank at 12:00".
 

Crackedback

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The guys got it. "Dot to dot" (cam sprocket [email protected]:00) is for degreeing the camshaft. Crank@ 12 and cam sprocket @12:00 is for installing the distributor.

I wanna see someone get the crank gear at 6 and cam sprocket at 12 as originally posted. That would be a skill. :D
Beanhead is a good dude. It's 6 oclock somewhere, time for a drink, right? LOL All good. We all get a little snarky on occasion.

As others have mentioned. If you leave it as is when installing, put distributor in with rotor pointing to #6
Set both dots at 12 o'clock. rotor at #1.

The book ignition timing for your car will not be close to right with a whiplash cam. Going to want around 15+ idle timing.
 
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flamesoldier

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I wanna see someone get the crank gear at 6 and cam sprocket at 12 as originally posted. That would be a skill. :D

As others have mentioned. If you leave it as is when installing, put distributor in with rotor pointing to #6
Set both dots at 12 o'clock. rotor at #1.

The book ignition timing for your car will not be close to right with a whiplash cam. Going to want around 15+ idle timing.
Very helpful thank you!
 

pnora

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If people just took the time to read the FSM they would learn and understand how to do these simple procedures. The FSM spells it out in two procedures. Gear and chain dot to dot for that procedure then a little further is distributor timing for the drive gear.. No one wants to read and learn any more. Its always gimme gimme or its been a long time since I have done one which translates into I have never done one.
 

flamesoldier

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If people just took the time to read the FSM they would learn and understand how to do these simple procedures. The FSM spells it out in two procedures. Gear and chain dot to dot for that procedure then a little further is distributor timing for the drive gear.. No one wants to read and learn any more. Its always gimme gimme or its been a long time since I have done one which translates into I have never done one.
Oh look another asshole in the group
 
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