Advancing stock cam in a 360?

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MopaR&D

MopaR&D

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The 360 in my D200 has always run a bit funny, kinda rough idle and harder to start than it should be along with garbage fuel economy. I finally checked the slop in the timing chain by barring the engine back and forth and there is at least 8 degrees of slack so I'm going to put in a fresh timing set. I ordered a Cloyes Street Billet True Roller set that can advance or retard in 2-degree increments. I'm thinking of advancing the cam 2 degrees, any thoughts? Maybe better to install straight-up, or advance it more (4 degrees)? It's a stock 1972 360 2-bbl cam.

Rest of the combo: refreshed stock heads, long tube headers, 2 1/4” true dual exhaust, Performer intake and AVS2 carb, upgraded ignition (CD box, Summit billet distributor). 727 trans, full-floating D60 rear end with 3.54 gears, 33" tires. It's just a cruiser and occasional hauler/tow rig, thought about upgrading the cam but with all the issues with junk lifters these days and the hassle of changing valve springs I decided to leave it alone.
 
I’d install it straight up and degree it. You won’t see big gains going forward or back 2-4 degrees on a stock cam, stock engine. Put it in where mother Mopar originally installed it and send it.
 
Advancing the cam 4* on any cam will cause the intake valve to close sooner and closing the valve sooner helps build cylinder pressure and increase pressure equals an increase in both torque and power, how much difference I don't know but since your installing a new timing chain why not Advance the cam. Every little bit helps
 
Dan the man said:
Advancing the cam 4* on any cam will cause the intake valve to close sooner and closing the valve sooner helps build cylinder pressure and increase pressure equals an increase in both torque and power, how much difference I don't know but since your installing a new timing chain why not Advance the cam. Every little bit helps
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Be careful using words like “any”, “every”, “always”, etc. The results with things like cam timing are rarely definitive. For example, if the cam has 4 degrees ground in already, and you move it forward 4 more degrees, do you think what you said would still hold true?
 
Back in the 70s and 80s my buddy would advance the cam gear 1 tooth on stock non hp engines. Really seemed to perk them up. I’m thinking it was 8* or more. I’m sure someone will do the math. Kim
 
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Straight up on the stock cam.

As far as the crappy starts, the mopar distributor HEI conversion works wonders.

You have to run an E-Coil with straight 12 volts powering it, no ballast resistor.

Hotter spark than the tower coils. Starts like it has fuel injection, along with using the newer mini starter. Mini starters spin faster and rob less voltage from your ignition system.

E-Coil top center pictured below.

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Inexpensive E-Coils at Rock Auto. Application use '95 Ford F-150, 2 post + & - spades for easy coil hookup.

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Get yourself one of these handy coil leads to go from the e-coil to the mopar distributor cap.

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Using this Mopar HEI conversion and E-Coil on the '89 D100.

Starts and runs great, just reach in through the driver's window hit the key, and it's running.

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☆☆☆☆☆
 
Advancing only 2 degrees is like carrying a BB gun for personal protection. You'll never feel the difference.
 
From Crane cams, years ago. To feel a difference, adv or ret the cam a MINIMUM of 4*.
 
TT5.9mag said:
Be careful using words like “any”, “every”, “always”, etc. The results with things like cam timing are rarely definitive. For example, if the cam has 4 degrees ground in already, and you move it forward 4 more degrees, do you think what you said would still hold true?
Click to expand...
You made a good point but chances of a factory cam having any advance already ground in it are slim
 
TT5.9mag said:
Be careful using words like “any”, “every”, “always”, etc. The results with things like cam timing are rarely definitive. For example, if the cam has 4 degrees ground in already, and you move it forward 4 more degrees, do you think what you said would still hold true?
Click to expand...
Good question. If the cam already had 4* ground into it and then it was advanced another 4* for a total of 8* wouldn't that cause the intake valve to close that much sooner? I'm just asking I'm not saying it would
 
TT5.9mag said:
Be careful using words like “any”, “every”, “always”, etc. The results with things like cam timing are rarely definitive. For example, if the cam has 4 degrees ground in already, and you move it forward 4 more degrees, do you think what you said would still hold true?
Click to expand...
Being in california you should be familiar with emissions. When I was more into engine rebuilding, the stock cams usually had retarded timing because of emissions. And I still believe that the little things that can be done to improve performance all make a difference. Look at the performance that's been made with pure stock drag racing those guys have to use all stock parts and no cylinder head mods of any kind except milling
 
In the old days the really only way to get any drivability on the street with the 292/509 was to advance it 6-8*. Everyone installed gears but almost never got a performance stall converter. Kim
 
oldkimmer said:
In the old days the really only way to get any drivability on the street with the 292/509 was to advance it 6-8*. Everyone installed gears but almost never got a performance stall converter. Kim
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Even with good gears and converter, extra advance does that cam good.
 
Dan the man said:
You made a good point but chances of a factory cam having any advance already ground in it are slim
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It was figurative, to prove a point.

Dan the man said:
Good question. If the cam already had 4* ground into it and then it was advanced another 4* for a total of 8* wouldn't that cause the intake valve to close that much sooner? I'm just asking I'm not saying it would
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Maybe. You’re recommending it so show us the results from your testing. I’m saying there are diminishing returns with regards to moving the cam that far.
Dan the man said:
Being in california you should be familiar with emissions. When I was more into engine rebuilding, the stock cams usually had retarded timing because of emissions. And I still believe that the little things that can be done to improve performance all make a difference. Look at the performance that's been made with pure stock drag racing those guys have to use all stock parts and no cylinder head mods of any kind except milling
Click to expand...
Yes, all to familiar with emissions testing. But I still wouldn’t go through the hassle of advancing a stock cam 2-4 degrees. I’d just put a different cam in it.
 
TT5.9mag said:
It was figurative, to prove a point.


Maybe. You’re recommending it so show us the results from your testing. I’m saying there are diminishing returns with regards to moving the cam that far.

Yes, all to familiar with emissions testing. But I still wouldn’t go through the hassle of advancing a stock cam 2-4 degrees. I’d just put a different cam in it.
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I probably would put a different cam in it too. With him seemingly only going to replace the chain I thought why not advance the cam. He probably wouldn't notice the difference
 
I know advancing 2 degrees from straight-up would be unnoticeable but the cam is currently at least 4 degrees retarded (8÷2) so I was thinking that little extra might help just a tad more and also compensate for possible future chain stretch. I'll go the full 4 degrees advanced as long as it won't increase the cylinder pressure too much. I'd love to just change the cam altogether but it's more work and expense (and risk) than I'm willing to deal with at this time. I'm not dead-set on anything just figured I'd ask y'all and see if anyone had experience advancing a stock non-HP cam.

@George Jets the ignition system is already overkill, Pertronix Digital HP CD box with their big coil (not canister-style). I put that stuff in back when I was still planning to swap in a built 440 but I gave up on that project soon after getting married lol.

It's not really hard to start it just takes a few more revolutions when cranking to light off compared to other Mopars I've rebuilt or tuned up. My Duster will fire off instantly on the first crank when it's warmed up.
 
oldkimmer said:
Back in the 70s and 80s my buddy would advance the cam gear 1 tooth on stock non hp engines. Really seemed to perk them up. I’m thinking it was 8* or more. I’m sure someone will do the math. Kim
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Good info, that's the kind of thing I was curious about. I know the theory about how this all affects valve timing but I'm wanting to know how it will actually run from others' experiences.
 
oldkimmer said:
Back in the 70s and 80s my buddy would advance the cam gear 1 tooth on stock non hp engines. Really seemed to perk them up. I’m thinking it was 8* or more. I’m sure someone will do the math. Kim
Click to expand...
Using a 46 tooth cam gear and a 23 crank gear, 360 degrees/ 23t would be 15.6 crank shaft degrees OR 7.8 camshaft degrees. SO yup 8*
 
If you really go to the trouble, get a degree wheel and do it. I just bet you'll find that the cam timing isn't where it's supposed to be anyway.
 
oldkimmer said:
In the old days the really only way to get any drivability on the street with the 292/509 was to advance it 6-8*. Everyone installed gears but almost never got a performance stall converter. Kim
Click to expand...
I have this cam waiting to use one of these days. Might need to advance it sounds like.
 
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