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First cam swap questions?

Myasylum

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Hello, I am doing my first cam swap and have some questions.
I purchased a Lunati 703 cam for my 400 engine.

I noticed though that with the stock cam still in place the dots on the Timing Chain matched up, and the Timing marks also were on "0"... so that was good however the dizzy on the distributor was pointing at the "7" cylinder, not the #1 cylinder. Why is that?
Also the pin for the fuel pump slid down when I pulled the cam out. How does that go back into place?
Should I try to get the carbon ring of the cylinders since the head is off? What should I use?
Tomorrow I am installing the new cam. I have to then make sure the dizzy is pointing at #1 at TDC correct?

Thanks much!!
 
Hello, I am doing my first cam swap and have some questions.
I purchased a Lunati 703 cam for my 400 engine.

I noticed though that with the stock cam still in place the dots on the Timing Chain matched up, and the Timing marks also were on "0"... so that was good however the dizzy on the distributor was pointing at the "7" cylinder, not the #1 cylinder. Why is that?
Also the pin for the fuel pump slid down when I pulled the cam out. How does that go back into place?
Should I try to get the carbon ring of the cylinders since the head is off? What should I use?
Tomorrow I am installing the new cam. I have to then make sure the dizzy is pointing at #1 at TDC correct?

Thanks much!!
You didn't note it but you need to purchase new lifters if you haven't already. If you didn't, RIP your brand new cam and engine.

Brake cleaner will take the carbon off the heads. I would take to a local engine shop and pay to have the heads decked since you pulled them off the engine because you may run the risk of blowing a new head gasket installing them back on the engine if they are warped.

No offense but it sounds like you are not very knowledgeable about this and you can ruin your engine if you dont do this right. Please go watch some videos, the timing of the cam has nothing to do with the distributor when you are installing it. You need to set the number one cylinder to TDC in the cylinder. Then you install your head and degree the cam and lash your valves accordingly.

As far as the fuel pump goes, you can just pull the fuel pump off if the pin slid out and re-install it. Easy.

Good luck
 
Hello, I am doing my first cam swap and have some questions.
I purchased a Lunati 703 cam for my 400 engine.

I noticed though that with the stock cam still in place the dots on the Timing Chain matched up, and the Timing marks also were on "0"... so that was good however the dizzy on the distributor was pointing at the "7" cylinder, not the #1 cylinder. Why is that?
Also the pin for the fuel pump slid down when I pulled the cam out. How does that go back into place?
Should I try to get the carbon ring of the cylinders since the head is off? What should I use?
Tomorrow I am installing the new cam. I have to then make sure the dizzy is pointing at #1 at TDC correct?

Thanks much!!
OP, you really do need to expand your knowledge of cam installation procedures. You can vary the distributor location after setting the cam. Be really sure the timing chain marks are correctly lined up. I learned after years that the degree wheel procedure will tell you if you are off. On the carbon ring, cover the piston with paper towel and use Brake Kleen and a good Scotch Brite. I wouldn't worry much about the carbon.
 
I have new aluminum heads and they were checked by a machine shop so I know they are flat.
Yes, I also have new lifters.
I just thought the distributor needed to pointing at #1 cylinder when at TDC.
I have a degree wheel coming today. That will be a learning experience, but I do realize the dots need to be aligned first and at TDC.
I just thought that carbon ring may need to be cleaned up since the cam will be changing how it was running.
Thanks
 
When changing over to different cylinder heads you’ll want to check pushrod length. It’s possible you’ll need a different length.
 
Are you sure it wasn't aligned up with #6 instead of #7, One and six are companion cylinders. You likely were 180 degrees off. You were looking at 1 at the bottom of the exhaust stroke not the compression stroke.

How are you aligning cam dot 6:00 crank dot 12:00? It's for installing cam not firing #1.

Regardless of how it was set up before is irrelevant. How you put it together NOW is important.
You will need a good dial indicator if your wanting to degree your cam.

Best results for align the distributer is if you shoot for the 2nd pic. Where #1 is doesn't really matter as long as it corresponds w the cap. It's just easier to follow this so the vacuum advance isn't in a bad place and you have to resequence all the plug wires..

Soaking with seafoam can remove carbon. Scuffing w a Scotch Brite pad is a good idea. But I would not worry about it. You are not doing anything that effects it. Really heavy carbon can cause detonation but unlikely in this engine.

Screenshot_20220710-091445_Chrome.jpg


Screenshot_20220710-091852_Chrome.jpg
 
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With the cam gear dot at 6 o'clock and the crank gear at 12 o'clock the engine will be at #6 FIRING not #1. Excuse me now as I've got to time this /6 cam before church.
 
Stupid question, missing the 3 bolts for the cam. Does it matter what bold I use? Should I use blue loctite?
 
Stupid question, missing the 3 bolts for the cam. Does it matter what bold I use? Should I use blue loctite?
Just a suggestion.................
cam bolts

Rats, the /6 cam is 108 ICL and not 106 ICL. Something for Monday I suppose.
 
Shouldnt need anything special. The 12 points are nice. Grade 5 minimal. Grade 8 better.
Shouldn't need lock tight. But doesn't hurt.

Screenshot_20220710-105554_Google.jpg
 
What is the torque spec for the 3 bolts?
Cam is in!
 
Here is a link to all of the torque specs you will need.

Mopar Bolt Torque Specifications – Big Block

Check out the Pete's Garage Youtube channel. He does a series on a build for a 440. Check out the vids on the cam install. Even though you are building a 400, not a 440, most of the info and insight will be helpfull.

I just completed a (first time) cam swap in my 440. A lot of help on this site, and the Youtube channel got me through the process. The BIGGEST piece of info that I got was the orientation of the cam gear. The dots are 12 o'clock for the crank gear AND 12 o'clock for the cam gear to have #1 firing. I almost messed this up.
 
Here is a link to all of the torque specs you will need.

Mopar Bolt Torque Specifications – Big Block

Check out the Pete's Garage Youtube channel. He does a series on a build for a 440. Check out the vids on the cam install. Even though you are building a 400, not a 440, most of the info and insight will be helpfull.

I just completed a (first time) cam swap in my 440. A lot of help on this site, and the Youtube channel got me through the process. The BIGGEST piece of info that I got was the orientation of the cam gear. The dots are 12 o'clock for the crank gear AND 12 o'clock for the cam gear to have #1 firing. I almost messed this up.
Good catch.
 
I was also told since this is a low compression engine to maybe set time timing 4 degrees advanced. Anyone else agree with this?

Lunati 10200703

Also... I have the cam installed, but it just made me wonder how far it's supposed to go in? Just till it stops? It seems to get tighter in the last cam bearing.
 
It should go all the way back so the timing gear needs to pull forward to be flush with the block face. Four degrees advanced would probably work well.
 
So then line up the dot on the top gear with the A4 on the bottom gear, correct?
 
The BIGGEST piece of info that I got was the orientation of the cam gear. The dots are 12 o'clock for the crank gear AND 12 o'clock for the cam gear to have #1 firing. I almost messed this up.
Explain this please?
 
At TDC intake the crank gear will have the dot at the top, the cam gear may also be at the top. depending on the timing set.
 
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