Good Cam for 318

-
X

xactorocker

Member
Joined
Dec 31, 2022
Messages
10
Reaction score
3
Location
Georgia
Hey, I have a 318 74 Gold Duster that I have a Holley 650 classic Edelbrock intake and then I have a set of hooker headers and a 2.5in exhaust. so next I'm looking for what is a good cam that I can easily street but has a good lope and a little more power. But one that does not have a high enough lift to where I need to pull the heads to check valves.
 
Last edited by a moderator:
Are you using the word "solid" as a term of "good cam for a 318" ? Or does it mean you want a "solid lifter cam"? If "solid" is a term word, and you want the rough idle but good street driver, then get a whiplash cam for the 318. If you want a solid lifter cam, then you know you'll need adjustable rockers and pushrods to match.
 
318willrun said:
Are you using the word "solid" as a term of "good cam for a 318" ? Or does it mean you want a "solid lifter cam"? If "solid" is a term word, and you want the rough idle but good street driver, then get a whiplash cam for the 318. If you want a solid lifter cam, then you know you'll need adjustable rockers and pushrods to match.
Click to expand...
no, i just meant it as in good I'm looking for something just to liven it up a bit I know options are limited for 318s cause 340s are much better but yes thank you for the recommendation!
 
Like anything it depends on your budget. I have run Summit brand SUM-6901 and their SUM-1789
in a 273 and 318 and was happy with how well the engines performed.
Of course if budget is on the high side the cams from Howards and Hughes are very good.
The Whiplash cam is designed for a stock lower compression engine such as the 318.It is a good one.
Also remember there are many variables as what the plan is for the cars usage.Meaning Street/Drag,Autocross or a daily driver.
Do you know the rear axle ratio ? That also is a variable when you choose.
EDIT; I just went back and re-read your post. If any cam change is happening,you will have to pull the heads
You "can" change valve springs while the heads are still on but.. A cam change without matching valve springs is a moot point.
 
Last edited:
Then there’s also the issue of if it has exhaust rotators… those will limit exhaust lift quite a bit. Then the valve lock grooves are lower on the exhaust valve stems which makes for another complication to work around.
 
anytime that you install a cam into a low-compression 318, that has a later than stock Intake valve closing event, with no other changes, the engine will lose power at low-rpm.
The usual band-aids for that are a higher than stock stall and bigger number rear gears.
The convertor is to insure that the engine never has to work in the soft zone.
And the gears; because without them, them, the power-peak in Second gear ends up waaay too far up the Speed-O-meter to be useful.
As I recall, the stock cam is 248/256/112 and it peaks around 4400. With an Ica near 52*, it makes already crappy cranking cylinder pressure of around 131psi @ sealevel. By the time you get to 600ft, the CCP is down to 128, and she will lose roughly 3>4psi per cam size. By the time you get to a 220*/110 cam, which may have an Ica of 60*, the CCP is down to 120psi which is pretty low. By this time the low rpm/sub-3000 is feeling almost like a good 225.
So you don't want your engine to ever have to work hard down there. So the very next thing you need, to go with that new cam, is a performance convertor with a higher than stock stall.
Now, that 220/110 cam will power-peak close to 5000, and the power with stock heads is gonna drop like a stone almost right away, so think about shifting at 5300.
Let's say your Gold Duster has 2.45 rear-gears in it, and you are running 27" tires,then; 5300 will be 64 mph in first/108 in Second; you see the problem?
But say somebody ditched the 2.45s years ago in favor of say 2.94s. Again at 5300, the speeds are 53 in First, and 90 in Second. At 65 in Second gear, the rpm will be ~3800; you see the problem?
To hit 75 say, at 5300, in Second, you will need 3.55s, and 65 in Second will be just 4600, some 400 rpm below peak power.
I heard you say:
That I can easily street but has a good lope and a little more power.
Click to expand...
but-um, IMO, you will get way more satisfaction with a higher stall and gears, than you ever will with a lopy low-lift cam. and
in the case of the low-compression 318, I have to say; forget about a wannabe-idle lope.
If it was me, looking for a lil more take-off and two-gear power, my first install would be a 2800TC, followed very shortly by gears of 3.73s +/- one gear size, and I would leave the stock cam in there, until I could afford to re-engineer that lowly smog engine, into a fire-breathing dragon.
Happy HotRodding
 
Last edited:
318willrun said:
Are you using the word "solid" as a term of "good cam for a 318" ? Or does it mean you want a "solid lifter cam"? If "solid" is a term word, and you want the rough idle but good street driver, then get a whiplash cam for the 318. If you want a solid lifter cam, then you know you'll need adjustable rockers and pushrods to match.
Click to expand...
I edited the title and the first post to stop the confusion. :BangHead::BangHead::lol:
 
xactorocker said:
Hey, I have a 318 74 Gold Duster that I have a Holley 650 classic Edelbrock intake and then I have a set of hooker headers and a 2.5in exhaust. so next I'm looking for what is a good cam that I can easily street but has a good lope and a little more power. But one that does not have a high enough lift to where I need to pull the heads to check valves.
Click to expand...
There have been novels written here about 318 cams. Use the search function and study. I see 17 pages of threads. Search results for query: 318 cam
 
I like going a tad big on camshafts when headers and decent induction systems are used. It pays off in spades in the mid range and top end pull. You can make up the slight loss in bottom end torque by advancing the camshaft a little further than the cam card recommends. To that end, I like this one.
www.summitracing.com

Summit Racing SUM-1798 Summit Racing™ Camshafts | Summit Racing

Free Shipping - Summit Racing™ Camshafts with qualifying orders of $109. Shop Camshafts at Summit Racing.
www.summitracing.com www.summitracing.com
It's the age old ".480 lift" grind that most everybody made. Not the fastest rate of lift, so it's easy on the valve train. Also it's not a name brand, but Summit's own in house brand, so you don't have to pay for someone's name brand or stupid snappy name like "Xtreme" or some such. This will also rattle it up with a good lopey idle. As long as you advance it say 2-4 extra degrees, you'll be fine. Opinions vary, but that's mine.

Here is this cam in a 318.
 
Last edited:
Yet another 318 cam thread that has the OP going from a .400 lift cam to a .500 lift on the first page.

...and all the other stuff.

I didn't even have time to get the popcorn smiley out.

I'd look at those Summit 6900/6901 cams, or for a more modern grind, the Comp XE 256 or Lunati equivalent.
 
RustyRatRod said:
I like going a tad big on camshafts when headers and decent induction systems are used. It pays off in spades in the mid range and top end pull. You can make up the slight loss in bottom end torque by advancing the camshaft a little further than the cam card recommends. To that end, I like this one.
www.summitracing.com

Summit Racing SUM-1798 Summit Racing™ Camshafts | Summit Racing

Free Shipping - Summit Racing™ Camshafts with qualifying orders of $109. Shop Camshafts at Summit Racing.
www.summitracing.com www.summitracing.com
It's the age old ".480 lift" grind that most everybody made. Not the fastest rate of lift, so it's easy on the valve train. Also it's not a name brand, but Summit's own in house brand, so you don't have to pay for someone's name brand or stupid snappy name like "Xtreme" or some such. This will also rattle it up with a good lopey idle. As long as you advance it say 2-4 extra degrees, you'll be fine. Opinions vary, but that's mine.

Here is this cam in a 318.
Click to expand...

That sounds pretty snappy. That's one of those old school grinds that worked well for years. Easy on the valve train and you don't have to have exotic pieces to make it work.
 
273 said:
Here's an stock low cr 318 with 4bbl xe262h cam and headers mod 1&2 base is stock 2bbl with headers.

TORQUE SUPERFLOW 901 DYNO-TESTED AT WESTECH
RPMBASEMOD 1MOD 2
2,000292
2,500287
3,000287338336
3,500272335340
4,000248326330
4500218309319
5,000188285296
5,500250258


318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine
Click to expand...
Thanks for the link. That's a decent gain over stock for sure. More than enough to keep a Teen owner smiling.
 
273 said:
Here's an stock low cr 318 with 4bbl xe262h cam and headers mod 1&2 base is stock 2bbl with headers.

TORQUE SUPERFLOW 901 DYNO-TESTED AT WESTECH
RPMBASEMOD 1MOD 2
2,000292
2,500287
3,000287338336
3,500272335340
4,000248326330
4500218309319
5,000188285296
5,500250258


318 Long Block Bolt Ons - Tech Articles - Mopar Muscle Magazine
Click to expand...
If you look at 3000 rpms and above the engine is making 50 to 100 lbs-ft more than stock. Even though it don't show under 3000 rpm for modified is't more than likely making over stock or at least stock torque numbers and under 2000 rpm even a factory stall will cover.

@318willrun has shown at the track a cam will work on low cr with stock stall and gears and picks up e.t., check his stuff on here and youtube.

https://www.youtube.com/@318willrun/videos

Plus torque makes less hp at lower rpms. so it's less sensitive to loss/gain of tq. hp % of torque at 2500 rpm is 47.5% and 2000 rpm is 38% and 1500 rpm is 28.5%. so 3-5hp for every 10lbs-ft.
 
273 said:
Problem is when it comes to 273/318 performance, most think you shouldn't touch them ever 360/408 only way to go, then there's the cr and velocity doomsayers.
Click to expand...
Facts and true word there.
 
I really wish those small displacement, small-ish cam dyno tests would start MUCH lower in the RPM range....

...because that's where people drive.

Obviously they had the capacity to show 2000 RPM numbers but for some reason, chose not to.

You can't "assume" the numbers below 3K were also higher.

If it were my car, I'd want off idle numbers.

Especially for a cam upgrade with an advertised power band starting at "idle" or "1500".

That's kinda the whole point of "data".
 
This! ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
YY1 said:
I really wish those small displacement, small-ish cam dyno tests would start MUCH lower in the RPM range....

...because that's where people drive.

Obviously they had the capacity to show 2000 RPM numbers but for some reason, chose not to.

You can't "assume" the numbers below 3K were also higher.

If it were my car, I'd want off idle numbers.

Especially for a cam upgrade with an advertised power band starting at "idle" or "1500".

That's kinda the whole point of "data".
Click to expand...

You sure about that? I seriously doubt you drive around at 2000 RPM at WOT on a regular basis.

Thats exactly why most people don‘t start the pull that low. It’s exactly like being in high gear, WOT and 2000 RPM. There is no reason to do that to an engine. Ever.

So when you are cruising around at part throttle and 2k RPM, exactly how do you measure that without multi-million dollar test equipment?

That’s why they don’t get pulled down like that. You are almost certainly running into trace detonation (at the least) doing things like that.

Of course, I’ve heard it argued that if you foot brake your car you start out that low at WOT. That’s true. BUT…at the beginning of the run you are not at WOT. You only go to WOT right before the green light comes on (unless you wait for the green and then you are first round fodder) and you aren’t just holding it there at WOT. You are at part throttle.

Dyno operators aren’t stupid. There is no reason to test for WOT at that low an RPM.
 
You must log in or register to reply here.
-

Back
Top