Cam advice wanted

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autopar3000

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Hey Guys,

I have the top end of my motor apart and I happened to notice that two of the cam lobes are wiped clean. I have no idea what the specs are on this dead cam, but it did the job for me and I was pretty happy with it. So now I need some advice on what cam I should get, and I'm pretty ignorant when it comes to cam specs. Hopefully you guys can help. Here's my setup:

-1978 318 .30 over
-small valve 360 heads with just a bit of a cleanup done in the bowl.
-Stock type piston (yes, down in the hole at TDC).
-Mr Gasket thin gaskets will be going back on it (to hopefully make up for the super low compression a little bit)
-LD340 intake (will probably upgrade to a performer soon).
-Carter 625 cfm carb.
-Headers going into 2.5" dual exhuast.
-Mopar orange box ignition
-904 trans with a shift kit and about a 2200 stall converter.
-3.23 gears in a sure grip 8 3/4 rear end.
-Electric fan.

I'm pretty much looking to make maximum power, with a slight (very slight) leaning towards torque over horsepower. It should have a good bump at idle, but at the end of the day it's a street car so it doesn't see high rpm situations all that often. But when I do get into the upper reaches of the rpm range, I still want it to go pretty good.

Soooo... ideas?

Thanks,
Mike
 
Your compression will probably be dead on 8.1. I would run something like the Comp 256.
 
Im kinda in your situation, and have a comp xe268 going in my small block dart to replace the 0701 voodoo cam in it. 9.5 flat tops, performer rpm, 650 eddy, 3.23 with a 727 and a Coan 2500. This is what the comp tech recommended, should be installed next tuesday, will let you know.
 
If you're 'just' changing the Camshaft, make sure you check the Valve Spring Pressure first.

If the Valve Spring Pressure is around #250 lbs. @ 1.20" Spring Height with the Valve Open, the
Compu-Cam XE-262 would also fit nice with that combination.

Lift............................ .462"/.470"
Duration..................... 262*/270*
Duration @ .050" Lift... 218*/224"

This Camshaft has an excellent response, and is a pretty good Cam for 'Mileage' as well.

The 'ramp' design is not too radical, and the Cam kicks in nicely at 1300 RPM's for
quick Low-End Torque.

Works fine with a Stock Converter, or +300 RPM over Stock Stall Converter.

Alot of guys call this Camshaft the 'Stock 340' "PLUS"

Works fine with 3.23 Gears, but is a Dynamite Street Cam with {3.55 or 3.91} Gears,
Headers and a Good 'Carburetor and Intake'.
 
.....and while you are in there changing the cam, don't forget to take the engine apart, clean everything, inspect everything, replace the oil pump, etc....If you wiped 2 lobes on the cam, those metal shavings are now running around inside your engine doing all kinds of damage....just sayn.
 
What 69 Cuda 440 (duration wise) and FlyFish said.
 
Ditto, but ya can't tell people Shyst!
 
The best damn overall Street/Strip Intake.

Edelbrock LD-340

43596489_scaled_320x240.jpg
 
Hey Guys,

I have the top end of my motor apart and I happened to notice that two of the cam lobes are wiped clean. I have no idea what the specs are on this dead cam, but it did the job for me and I was pretty happy with it. So now I need some advice on what cam I should get, and I'm pretty ignorant when it comes to cam specs. Hopefully you guys can help. Here's my setup:

-1978 318 .30 over
-small valve 360 heads with just a bit of a cleanup done in the bowl.
-Stock type piston (yes, down in the hole at TDC).
-Mr Gasket thin gaskets will be going back on it (to hopefully make up for the super low compression a little bit)
-LD340 intake (will probably upgrade to a performer soon).
-Carter 625 cfm carb.
-Headers going into 2.5" dual exhuast.
-Mopar orange box ignition
-904 trans with a shift kit and about a 2200 stall converter.
-3.23 gears in a sure grip 8 3/4 rear end.
-Electric fan.

I'm pretty much looking to make maximum power, with a slight (very slight) leaning towards torque over horsepower. It should have a good bump at idle, but at the end of the day it's a street car so it doesn't see high rpm situations all that often. But when I do get into the upper reaches of the rpm range, I still want it to go pretty good.

Soooo... ideas?

Thanks,
Mike

Almost the same setup here ... and was wondering about the same question. :thumblef: :grin:

Maybe a stupid question, but can you change a cam with the engine in the car?
 
Yes,

You will have to take the Grille Trim section out, and bend or possibly cut
the thin-metal vertical {radiator housing support brace}.

Of course, removal of the {radiator and front engine bolts ons}.
 
camquest6 at compcams.com

The cam is the most important piece in your engine. Leave to the pros who do it day after day.
 
OK, so far I'm seeing the following suggestions:

Comp 256
comp xe268
Compu-Cam XE-262 (x 2)
camquest6 at compcams.com

Since I'm so cam-ignorant, I'll probably end up with one of those. Thanks guys! BTW... more suggestions are welcome.

As for the LD340, the reason I bought it is becuase lots of people (on this board) have said that it's the best thing since Texas toast, but some others say you can't beat the more modern technology that has gone into the newer intakes. Which to me kinda sounds like something someone trying to sell new intakes would say, so maybe I'll stick with the LD340.

Thanks again FABO, best forum on the net.
 
Autopar 3000

The Edelbrock LD-340 is a damn good intake, and works so well on the street,
where a little more torque and lower RPM power desired.

Since you already have it, no reason to switch to a Performer to gain at best
nothing.

And, with 8.0 to 8.5 Compression and Small-Valve 360 Cylinder Heads, anything
bigger than a .470" Lift and 270* Camshaft will make that Engine 'flatten out',
especially with a Stock Converter and 3.23 Gears.
 
This guy takes the words right outta my mouth.
X's2!


Autopar 3000

The Edelbrock LD-340 is a damn good intake, and works so well on the street,
where a little more torque and lower RPM power desired.

Since you already have it, no reason to switch to a Performer to gain at best
nothing.

And, with 8.0 to 8.5 Compression and Small-Valve 360 Cylinder Heads, anything
bigger than a .470" Lift and 270* Camshaft will make that Engine 'flatten out',
especially with a Stock Converter and 3.23 Gears.
 
Autopar 3000

The Edelbrock LD-340 is a damn good intake, and works so well on the street, where a little more torque and lower RPM power desired.

Since you already have it, no reason to switch to a Performer to gain at best nothing.

And, with 8.0 to 8.5 Compression and Small-Valve 360 Cylinder Heads, anything bigger than a .470" Lift and 270* Camshaft will make that Engine 'flatten out', especially with a Stock Converter and 3.23 Gears.


Between the unplanned much extra money I'm spending on the car right now and the advice I'm getting from you and others, I'll probably end up keeping that LD340.

Do you think I'm running 8.0 - 8.5 compression? Others have told me it's probably around 7.5. Maybe those thin gaskets will help get it all the way up to 8.0.

My converter is a little hotter than stock, but I totally hear what you're saying about a big cam flattening this motor. In fact, after looking at all the options I ordered the very cam that you suggested.

But since the heads are off and I have to wait a week + for the cam to arrive, now I'm considering having the heads milled a little bit. So of course I have questions...

How deep of a cut do you guys think I should do? I don't want the compression too high, because I really like the fact that I can run 87 octane. 89 might be acceptable, but once I get into the 91 range I'm looking an extra $10 per tank of gas, so I want to be careful with this. Also, I don't suppose I could have the heads milled without having them disassembled, could I?
 
You can not mill that much off the head to require 91 octane. The heads must be disassembled for milling. I would not go this route myself since there is a lack of money (Your complaint about an extra $10'per week/tank) and the gain small.

Once you mill the deck, the intake face of the head must also be milled to keep things aligned and correct. To mill the head as much as you would need to get a meaningful ratio, you'll run out of material on the intake face of the head and you will need to mill the intake itself. This becomes a pain in the backside.
 
Also a word on the newer intakes vs. the older LD-340.
While there would be a gain, it is small and not really worth the expense of the intake that you all ready have. The modern intakes are better. But at $250???
I'll keep my LD-340 thank you very much. There just fine for the street.

If I didn't have an intake the 2 RPM offerings are very good. Choose the regular RPM for year round useage and the air gap for more pleasent year round weather useage. Also the Weiand Action Plus is another excellent intake with a heat cross over.
 
Autopar,

What Casting Numbers are on those 360 Cylinder Heads {#4027596}. ???

Having the head surface 'cleaned up' is probably a smart thing to do, especially
if you're going to use a thin 'shim-type' Head Gasket.

The thin 'shim-type' Head Gasket {.025"} versus the Fel-Pro Head Gasket {.039"}
is about {.25} in Compression difference.

If you have the #4027596 '360 Heads', you should have no problem getting the
surface 'cleaned-up' with the valves in-place, to provide for a proper micro-finish' surface.

If you want them milled in any significant amount........different story.


Picture126.jpg
 
Hey guys,

So I got the engine all back together now. The new cam certainly is different from the old one. The engine sounds WAY different than it used to; before it was very beastly sounding, with a pretty rough idle. It sounded like a vintage engine and people could hear me coming from a mile away. NOW, it's much smoother at idle, and in fact it's much smoother all the way up the RPM range. Somehow, the engine sounds like a more modern engine. And QUIET! I can't believe how quiet the car is now, especially at crusing speeds! Headers with 2.5 inch and flow through mufflers, and I can barely hear the exhust growl at 50 mph.

I haven't wound it out to max RPM just yet. I'm still running the break in additive in the oil and I want to give it a few more miles before I start beating the hell out of it. So at this point I can't really tell if the car is any faster or slower than it used to be.

But one thing is for sure - the timing needs to be adjusted. I had the car out in the rain yesterday and I had trouble breaking the tires loose! I figure the brutally poor power at the low end can't be becuase of this cam (it should be better on the low end, given how wild the old cam was + 2 wiped lobes), so it must be the timing.

Given what you guys know about my setup, how do you think I should have the timing set?
 
Check out "distributor curving",in the search feature. Or let's see if someone response.Bump.
 
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