Cams for 318's

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remember a 268 MP cam has similar seat durations to a 275 comp (@.006) or 280 crane (@.004)
what compression does a 275ish comp want?
you can see the durations of the stock 340 cam in an above post at .004 and .006
the summit cam is @.004 and is an oldie but goodie chevy grind
with similar durations a mopar lobe will have more area under the curve
What kind of numbers would it have? Inquiring minds want to know.
 
6901 I think I have posted on that elsewhere
first depends on your build
there was a foreign user that was looking at it, south america, decided to just go 4bbl andchange his oem timing chain
It's an old Cam Dynamics grind now ground by Crane and most every copy cat grinder
Elgin's may be more cost effective
stock 340 grind may be more cost effective
start a new thread in the regular area
you can find it at other similar on page 2 of this thread
you can get lots more area under the curve at the same duration
if the durations and timing are what you need in the first place
most likely not
 
toolmanmike posted in another thread
Basic 273 cam specs: solids

1965 180 hp 2 barrel .395 /.405 lift 240°/ 240° duration
1965 235 hp 4 barrel .415 /.425 lift 248°/ 248° duration
1966 235 hp 4 barrel .420 /.430 lift 248°/ 248° duration

note -you can go to the Victory Library link above and look at Some of the DC/MP solid cams
what is nice about MOPAR is that the duration method is the same for the stock cams and the MP/DC cams and is NOT just at some arbitrary lift
MOPAR starts where the clearance ramp changes to the acceleration ramp
so solid cams with different adjustment clearances are automatically taken care of
.020 advertised or .050 - you cannot compare unless the tapped adjustment clearance is the same
some aftermarket companies use SAE which is .006 at the valve- that you can compare and if you look hard you can find SAE for most MOPAR cams
HOWEVER the timings given in the FSM and in the Victory listings are mostly useless except to compare one MOPAR cam with another- you can not even use them to set/ check the timing
 
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from another thread
VooDoos are true Chrysler profiles, designed for the .904" tappets.
That 213/.454" profile is about 5 or 6 degrees fatter at .200 than the Chevrolet one.

UDHarold


similar differences between flat flank and IR rollers


`Following up on UDHarolds observation that the Mopar series gives more duration (flow) at .200 and my observation that I shorter seat may be utilized on builds that do not have compression maxed out
Lunati 260 260/260 210/210 441"/.441" typical of universal (Chevrolet) grinds
one size shorter seat Voodoo but more at .050 and more lift
60401 256/262 213/220 .454'/.475"
two sizes shorter seat Voodoo still more lift this is still a fatter lobe than the universal
60400 250/256@ seat 208/213@.050 .454"/.454" valve lift,
but would build more cylinder pressure- would close the intake about 5 degrees earlier than the universal-Chevrolet one All UDHarold designs so apples to apples

As has been said you could use a 260 voodoo and get more horsepower
but this version of optimization gives a fatter torque curve
the 60400 and 60401 Voodoos were selected by Harold and his designs

For you it's not the additional hp
it's being able to run one size shorter cam and still have a little more hp while really picking of the get away experience

You can do the same drill with IR vs Flat flank rollers
 
OK Hyd rollers
Lets assume that careful analysis indicates that a 270 @ .006 duration is optimal
I'm going to pick the lobe- the more radical may not be street, they may take more and more often spring changes


First 3 Ultrdyne lobes
Ultradyne UD Harold Lobes 1.5 rocker
HR5 270 206 111 0.401
HR27 271 217 138 0.516
HR23 272 218 141 0.530

Then 4 bullet lobes
Bullet lobes lobe
HR270/330 270 218 138 .3300 .000 CTS
HR270/313 270 218 132 .3130 .000 CRA
HR270/3175 270 212 130 .3175 .000 CTA
HR270/2775 270 214 119 .2775 .000 CRA

and some Inverse radius lobes- 3 268 lobes to compare with the flat flank 270 lobes if you wanted more Horsepower and then one size shorter seat and two sizes shorter seat
ERH Series
268 222 143 .340 .510
264 218 149 .340 .510
260 211 126 .316 .474


HR series

268 218 136 .325 .487
268 210 126 .312 .469
264 212 128 .310 .465
260 210 132 .313 .469
260 208 128 .327 .490

note how well the .200 can hold up with the shorter seat durations
If you get a custom cam from anyone be sure to get the optimum radicaliness for your use
do not buy from the bottom of the catalog-

UD Harolds comments are from
Mopar stroker cam selection? Please help! - Don Terrill’s Speed-Talk
Mopar stroker cam selection? Please help!

you will notice how the .200 is more useful than .050 for power
but again do not just specify the big number= it may be race only
and seat timing for dynamic compression- low end punch
 
Adding Howard to the discussion of flat flank VS inverse Radius

260 @.006 class
bhr 260 207 123 .300 .450 Howard BHR StandardRampHydraulicRoller
bhr 262 209 127 .310 .465 Howard BHR StandardRampHydraulicRoller
EHR 260 211 126 .316 .474 Jones Inverse Radius
HR 260 208 128 .327 .490 Jones Inverse Radius
HR 260 210 132 .313 .469 Jones Inverse Radius
BHR 266 213 133 .323 .485 Howard BHR StandardRampHydraulicRoller


.006 is comparable to Ultradyne and Bullet above
Howard and Bullet have shorter lobes as necessary
I try and look at the .200 and not chase the last few thou of lift
which is more of a "mine is bigger than yours"
and may require more spring

270 @.006 class
bhr 268 215 132 .313 .470 Howard BHR StandardRampHydraulicRoller
bhr 268 215 132 .333 .500 Howard BHR StandardRampHydraulicRoller
bhr 270 217 133 .310 .465 Howard BHR StandardRampHydraulicRoller
bhr 270 217 136 .323 .485 Howard BHR StandardRampHydraulicRoller
bhr 270 217 137 .330 .495 Howard BHR StandardRampHydraulicRoller

HR 268 210 126 .312 .469 Jones Inverse Radius
HR 268 218 136 .325 .487 Jones Inverse Radius
ERH 268 222 143 .340 .510 Jones Inverse Radius

AHR 269 219 143 .353 .5294 Howard AHR AggresiveRampHydraulicRoller

no one is suggesting an aggressive ramp for a heavy valve conservative street build
At least Howard breaks out their aggressive ramp series
 
Schneider cams has a 224@.050 .473 270 110 solid I used a couple times with great results in both the 273 with ported heads and a 'stretched to 340' 318 with mildly ported 273 heads w/1.88s that made 305hp by 5400 and 375tq@3800-4200
The 273 had a ton more torque and a very broad range. A great small solid cam to run around with.
 
I may have posted this before from some of my old notes

Mopar is very consistent on how they measure cams
they take the blueprint point of where the clearance ramp meets the acceleration ramp and subtract 4 degrees from the opening side and 4 degrees from the closing side
The height of the clearance ramp therefore makes no difference
Turns out this gives close to .008 but varies
you could do this same drill with Racer Brown or Engle who use .008
The chart is both opening and closing so not perfect for asymetrical cams where the close would be longer than the opening to minimise valve bounce

340 Cam 268 208 closes 66 ABDC 114LCA 60 intensity
DC 268 cam 228 closes 62 ABDC 110LCA 40 intensity
DC 280 cam 238 Closes 66 ABDC 110 LCA 42 intensity
DC 284 Cam 241 Closes 70 ABDC 108 LCA 43 intensity
DC 292 Cam 248 Closes 74 ABDC 108 LCA 44 intensity

for all those that recommend advancing the 340 cam 4 degrees the MP 268 cam gives you a much fatter lobe and you can go to the 280 and close the intake about the same place
I do not see my notes for the DC 260 or 248
 
@Old vc

You hit the X on me for stating a fact that a factory magnum rocker ratio is 1.6.

You're wrong.

A message to all those who hit the X ..
If you hit the x.... YOU BETTER KNOW WHAT YOU ARE TALKING ABOUT and you basically suck imo.
If you hit the x AND don't even have a rebuttal ... you double suck and really..what are you doing here.
 
Thumper
Cams in the Thumper intake durations ranges from Comp, Lunati, Howard, Hughes etc @.006
Some Factory.Engle and MP cams converted to .006
with some suggestions by readrs
 
Mopar Cam- how many more degrees @.006 to equal at .200?
This thread tries to show how much .200 duration (a proxy for power cyl fill)
you loose using a .942 cam in a mopar
and gives alternatives

you will find it can take an additional 20 degrees seat duration
thats like retarding 8 degrees
(then illuminarti recommend advancing these cams 4 degrees) timing is FUBAR
and there goes your dcr, low end, idel,gasmileage expansion ratio by opening the ex early

340 cam specs?
finely gets to discussing 340 cam in 318
 
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ok... looking at these numbers in the posts my head is spinning....
another 318-cam Q. 78 Sport Fury, 318, 904, 2.76. warm weather daily driver/ cruiser.
want to wake it up a bit "off the line" So far dead stock OEM except for true duals.
car has 53k original miles I am 2nd owner, Ive had since 2007.
don't want to get too crazy with it still want the wife to be able to jump in and go as she can with it being stock. just with a bit more oomph. I still have yet to delete the Lean Burn, have all parts needed here for that.
I did put an Edelbrock True Roller timing chain in when I did the water pump, just afraid of the original nylon toothed POS at 40 years old. I have an old Offenhauser alum 4 barrel here and a Performer intake (not RPM)
also have a set of fresh from the machine shop, 302 heads. All 16 valves are brand new, along with guides as needed (I forget how many guides he did, may have been all exhausts??? Need to dig out the bill)
I want to put a slight cam in that will actually work in here to do what I am asking, along with those 302 heads and either a TQ or a carterbrock 9511 (500 cfm) or a 9626 (have all on hand)

1st 2 cam choices (because they are here, and that don't mean I "Have to" use either)
Stock 360 cam (dead ringer for COMP 252 except 0.015" less lift) I used one of these in a 318 LA that I also put a std Performer on, new EQ Magnum heads and Hooker Super Comps at the same time. That was in a D250 that was USED as a truck, hauling/towing, the whole bit... huge improvement from stock but that truck also had 3.55s and taller tires

COMP 260 would this be too big for the 318? My son ran this one in a 360 for ~5k miles then pulled the engine back out and apart for a mystery oil eating issue, wound up putting a stroker crank in it and turning into a 408, and went with machine shop suggestion for the now larger engine

I have heard of the Comp 256, would have to scope that one out.... might be a possibility

I put the 248(?) in a short bed D100 w/a '69, 318 Edelbrock "Streetmaster 318" and a 625 AFB/ and a 833 OD and 3.91s years ago as I was "afraid of" the 252 being "too big" way back then.... probably would have been fine. did the "pick a cam and back up 1" in the catalog I was gun shy at the time, because the previous 318 to that was a 77 motor in a '75 Cordoba, all stock except a 4 barrel and (I forget the rest of the specs) an Erson cam (back in the "Super Shops" days) that as I remember (hey that was the 80s, memory is fading) was a .429/.444 cam of I forget what duration, etc that was a total slug. Lots of noise no go.....

have also thought of sending that stock 360 cam that I have to Oregon Cams for a "touch up" and slight grind, as that one too, is used. when I did the one in the 83 D250, mentioned above, I bought a new Melling 360-2bbl "stock replacement" and used the magnum heads' 1.6 RR which won't be the case this time. Found one new in box for like $80, but that was 10 years ago.....
I only got thru 1/2 of this thread previous to adding my post as I have to let my head stop spinning from all the numbers presented to that point....

so to recap/// want to warm up a 53k original mile 318 in a 78 2 dr Fury (B body) and want to know which cam to use with that short block + 302 heads+ one of the intakes I have on hand+ one of the carbs I have on hand...
May eventually consider a gear swap from the 2.76 (I don't think 2.94 would be enough of a noticeable change) so looking to go 3.08 (yes these are available for the 8-1/4 since the square body Cherokee days) or (at most) 3.21. But that's a ways down the road, will stay with the original 2.76s "for now"

right now the car is a bit more doggy than I like but it loves cruising the highway at 70 and is great on gas in doing so.... I don't mind sacrificing "a little bit" of the "good on gas" to get what I want.
 
can a mod here do me a favor? Break off that last post into its own thread? I mistakenly thought "tagging it along" with a sticky that is relevant was the way to go but Ive had PMs asking me to split it off....
and let mw say that looking at the numbers in the past posts in this sticky trying to figure out the "right cam for me" is making my head spin
 
can a mod here do me a favor? Break off that last post into its own thread? I mistakenly thought "tagging it along" with a sticky that is relevant was the way to go but Ive had PMs asking me to split it off....
and let mw say that looking at the numbers in the past posts in this sticky trying to figure out the "right cam for me" is making my head spin
I will leave it for now. There is 6 pages of information and thoughts about the subject. Your post is more information.
 
From the cam reveal thread
here are some similar duration cams to his fine for him choice of Engle K52

HM2103219A .483. .322 257 210 130@20 Howard-quite a bit faster ramps This is a bigger cam but I think shortest Howard shelf .904 cam
Hughes .473 .320 206 hug rejected cuz they push the envelope too hard I will not buy a cam with no seat durations too many variables
Voodoo.....454. 302 253 208 Voodoo 700 bout the same LCA different?
K-52HYD .458" .305" 254° 209° (did no one notice that Engle is at .008 like MP and Factory and Racer Brown- gotta adjust folks more like a 260 cam but a good one)
Jones........ 461 .305 256@ 202 128@ 200 actual seat is quite a bit shorter - see duration at .004 below .002 duration is shortest of everything on this page except MAYBE the Crane)
.842 ..........458 .305 272@ 216 with same lift note the extra duration it takes to get similar lobe (anyone think that 6 degrees does not make a difference)
.842 ..........434 .289 256@ 200 with same duration much less area
xe 256H ......447 .299 256 212 intake close 54 ABDC w/ 110LCA all the 256@.006 w/110 lca are going to close about the same for DCA use (Jones and Crane are shorter actual seat to seat)
Summit 6400.444 ,296 280 214 Edelbrock 288SAE .004 For comparison Jones is 264 @.004 24 degrees longer seat and less lift what's not to like
Crane H202 .432 .288 260@.004 202 113@200 Shortest Crane .904 H2 series also good wearing cam shorter than the Engle or Jones
Bullet..........432 .288 254 206 120@.050

some notes
Me personaly only use the fast ramp cames
the Howard, Hughes, Comp with lighter 11/32 valves and beehive springs
I know for a fact that the Mike Jones " motorhome" cam was designed for the even heavier than stock BBM Motorhome valves and it wears extremely well even with these
Youu can pick up some rpm with lighter valves and springs and alonger exhaust-peronal observation
Engle also has a big nose and wears well
 
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FYI, I have ran a dozen or so cams on the dyno program and although they aren't the most accurite, The mild cams were all about the same as far as HP and torque on a basic stock teen.
 
The biggest cam I tested (staying below 230° duration) is the Hughes Whiplash #SMC1326AL 213/226° .480/.516 cl 109°. It produced good numbers but it is on the ragged edge for a stock converter.
 
Charles @ Camcraft cams offers some good grinds for early A engines as well as a 340 cam.

Great guy to deal with...he offers a wealth of knowledge and is a racer himself.

camcraftcams.com
 
Earlier in this thread there was mention of a Mike Jones cam for 318's.
 
Well, I'm late to this conversation, but have spent the last two days reading through all of it. My question is: what does everyone think of the stock 360 2bbl cam in a 318? I didn't see anyone mention it on here. It has a little more duration and lift than the stock 318 cam. The overlap is a little more too. Looks like the intake closes 6 degrees later than the 318 cam per my 1973 Plymouth and Chrysler service manual. It seems that if it worked that great then Chrysler would have put the same cam in both engines. I have a 1986 318 2bbl in a D150 that has a flat lobe on the cam. It has the 302 heads so it has a little more compression than the earlier models. If I can get a little more performance from that 360 cam I would buy it vs. buying a stock 318 cam. I like the spec's on the Lunati 10200700 and Howards CL711381-10 cams though replacing the valve springs is out of my budget. I'm hoping that someone here has already done this and can tell me if they like it or not.
20201203_234910.jpg
 
@Old vc

You hit the X on me for stating a fact that a factory magnum rocker ratio is 1.6.

You're wrong.

A message to all those who hit the X ..
If you hit the x.... YOU BETTER KNOW WHAT YOU ARE TALKING ABOUT and you basically suck imo.
If you hit the x AND don't even have a rebuttal ... you double suck and really..what are you doing here.

People who hit the X with no rebuttal are pussies.
 
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