318 cam shaft selection/upgrade for stock engine

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MObarracuda

MObarracuda

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Let's start by saying I don't know cam shaft selections.....i have a bad lifter or a wiped line on my current cam shaft. I need to replace but want the most from the cam shaft but I want to maintain the good vacuum (18+). The. Edwlbrock 318 streetmaster with its single plane design and narrow runners seems to make very good vacuum. I have read a lot of posts about recommendations for cams but none that I have found state the vacuum that maintained or lost after the cam swap.

Please see the three cams listed at the bottom after reading about my car and components. Does anyone have experience and been happy with the performance of their power brakes after using these Summit cams that would work in my car?

-engine has stock
-340 exhaust manifolds
-dual exhaust with H pipe
-8 3/4 with 3.23 gears
-904 transmission with stock tourqe converter
-318 Edelbrock streetmaster intake (yuk on the top end, but makes 20 inches of vacuum and it was the only square bore intake i had)
-original power brakes (need alot of vacuum to work)
-stock cylinder heads

hydraulic Flat Tappet, Advertised Duration 272/272, Lift .454/.454, Chrysler, Small Block
https://m.summitracing.com/parts/sum-k50052

Hydraulic Flat Tappet, Advertised Duration 278/288, Lift .421/.444, Chrysler, Small Block
https://m.summitracing.com/parts/sum-k6900

Hydraulic Flat Tappet, Advertised Duration 276/288, Lift .441/.441, Chrysler, Small Block
https://m.summitracing.com/parts/sum-k6901

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None of the above.
318's had wimpy cams from the factory. Look up their specs.
Replace it with a modern grind that makes some more cylinderpressure while keeping the duration say well under 265 degrees advertised.
 
None of the listed cams will come close to 18 inches of vacuum.

You are looking at a cam with duration at .050" lift in the 190' to low 200's range, and with an LSA of 112 or even 114. The specs above keep the overlap down, which keeps the vacuum up.
Racer Brown EH-4
Crane H248-2
Or maybe a step up from these 2 at the MOST like the Crane 693902 or Comp XE CL20-220-3 in the Summit catalog.

No knarly idle with these cams.

FYI, I have run a cam like the first 2 above and had 19-20"of vacuum.
 
Those last 2 Summit cams (6900/6901) are really good value items for a mostly stock 318.

I'd also include the Comp XE256.

WAY better than stock .399-.400 lift, and no mods really needed to anything else.
 
YY1 said:
Those last 2 Summit cams (6900/6901) are really good value items for a mostly stock 318.

I'd also include the Comp XE256.

WAY better than stock .399-.400 lift, and no mods really needed to anything else.
Click to expand...

I put a Summit 6901 in my son's stock 318 and it works great. Cheap cam kit and good quality.
 
the 421/444 lift cam is best for an engine with manifolds, the 441/441 works best with headers.
 
my 323 with a Mopar Performance P4452757AE cam Kit with milled 360 heads, Eddy RPM intake 7176 and a 625 Street Demon carb with 3.55 rear gears. It works great, idles nice, good vacuum, lots of low end grunt and goes like hell for a 318 .30 over.
Purple Shaft Hydraulic Camshaft & Lifter Kit
Chrysler 273, 318, 340, 360
Advertised Duration: 248°/256°
Centerline: 110°
Lift: .410"/.425"
RPM Range: 1000 to 5000
Duration at .050'': 211°/218°
 
Last edited:
d1970 said:
my 323 with a Mopar Performance P4452757AE cam Kit with milled 360 heads, Eddy RPM intake 7176 and a 625 Street Demon carb with 3.55 rear gears. It works great, idles nice, good vacuum, lots of low end grunt and goes like hell for a 318 .30 over.
Purple Shaft Hydraulic Camshaft & Lifter Kit
Chrysler 273, 318, 340, 360
Advertised Duration: 248°/256°
Centerline: 110°
Lift: .410"/.425"
RPM Range: 1000 to 5000
Duration at .050'': 221°/218°
Click to expand...


As recommended by many here for a "teen" that is basically stock, keep the duration below 220° @ .050. Low to mid .400 lift is easy on valve train.
 
d1970 said:
my 323 with a Mopar Performance P4452757AE cam Kit with milled 360 heads, Eddy RPM intake 7176 and a 625 Street Demon carb with 3.55 rear gears. It works great, idles nice, good vacuum, lots of low end grunt and goes like hell for a 318 .30 over.
Purple Shaft Hydraulic Camshaft & Lifter Kit
Chrysler 273, 318, 340, 360
Advertised Duration: 248°/256°
Centerline: 110°
Lift: .410"/.425"
RPM Range: 1000 to 5000
Duration at .050'': 221°/218°
Click to expand...

Wait!
221@050 and 248 advertised? that's 27* from seated to .050. That is the fastest FTH I have ever seen. What's the PN?
I just gotta have one of those.
Every teener should have one of those.
 
AJ/FormS said:
Wait!
221@050 and 248 advertised? that's 27* from seated to .050. That is the fastest FTH I have ever seen. What's the PN?
I just gotta have one of those.
Every teener should have one of those.
Click to expand...
Roller? Lol
 
Naw, you CAN get more lift and keep the duration low and will be waaaaaaay ahead of the stock cam. I wish there was still data somewhere on the 70's Crane HE cams.... hydraulic efficiency cams. (Any one have a late 70's Crane catalog?) They cam out in the wake of the 1st Arab oil embargo. High lift, low duration, wide LSA. Not at all like a stock cam in terms of performance. Good economy, good idle, excellent torque, good HP if you had good breathing parts in the rest of the system. EASY to get 1 ft-lb and maybe .85-.9 HP per CI with a cam like that.

Guys who have never run such a cam just don't know....shoot for just under 1 HP per CI rather than 1.1 or 1.2 HP per CI and it is a whole new world. Torque, economy and wide torque range is all there to be had. No foolin'....
 
nm9stheham said:
Naw, you CAN get more lift and keep the duration low and will be waaaaaaay ahead of the stock cam. I wish there was still data somewhere on the 70's Crane HE cams.... hydraulic efficiency cams. (Any one have a late 70's Crane catalog?) They cam out in the wake of the 1st Arab oil embargo. High lift, low duration, wide LSA. Not at all like a stock cam in terms of performance. Good economy, good idle, excellent torque, good HP if you had good breathing parts in the rest of the system. EASY to get 1 ft-lb and maybe .85-.9 HP per CI with a cam like that.

Guys who have never run such a cam just don't know....shoot for just under 1 HP per CI rather than 1.1 or 1.2 HP per CI and it is a whole new world. Torque, economy and wide torque range is all there to be had. No foolin'....
Click to expand...
No one around has a old Crane book. Too bad. We could have some old numbers reground and make a fortune. I hope someone comes up with some old info. I managed a speed shop in the 70's and don't remember many Crane cams with that combo. Many cams back then were heavy on the duration side and low lift.
 
So will a regular 213/226/109cam
The whiplash just adds the raunchy idle.That's all it does.
Notice the hype "scares Mustangs,Camaros and rice-burners.

I call it a poser-cam. It poses as a 292/292/108 type cam when idling, but when you get on it, it's really a pussy. Well, it has a strong bottom end for sure, just like any other 213/226/109 , and with 3.55s and like the hype says stock or mild stall, will make a strong show on the street.
But a 213 is about a 259 in regular FTH cam-speak, so the power peaks at the same rpm as a regular 259cam. No surprise, a streeter might never miss the high-rpm power, cuz first gear is good to over 50mph@5500. I think it's a great cam for some guys.
But for me, if it sounds like it might be an 11 second car, it should go like it; namely power to 5800 and a shift rpm of 6800, or more; at least zero to 63mph in first with 3.55s.(63 is about the speed-limit here where I live.)
That's my opinion
 
One of the smaller Lunati Voodoo grinds would be a good choice.
 
RustyRatRod said:
One of the smaller Lunati Voodoo grinds would be a good choice.
Click to expand...
Something like this

Cam and Lifters, Hydraulic Flat Tappet, Advertised Duration 265/265, Lift .454/.454, Mopar, 273-360, Kit

https://m.summitracing.com/parts/lun-80360lk

Basic Operating RPM Range:1,200-5,000

Intake Duration at 050 inch Lift:216

Exhaust Duration at 050 inch Lift:216

Duration at 050 inch Lift:216 int./216 exh.

Advertised Intake Duration:265

Advertised Exhaust Duration:265

Advertised Duration:265 int./265 exh.

Intake Valve Lift with Factory Rocker Arm Ratio:0.454 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio:0.454 in.

Valve Lift with Factory Rocker Arm Ratio:0.454 int./0.454 exh.

Lobe Separation (degrees):110
 
No, That's not a VooDoo grind. The VooDoo grinds are split pattern cams, which I believe will work better.

MObarracuda said:
Something like this

Cam and Lifters, Hydraulic Flat Tappet, Advertised Duration 265/265, Lift .454/.454, Mopar, 273-360, Kit

https://m.summitracing.com/parts/lun-80360lk

Basic Operating RPM Range:1,200-5,000

Intake Duration at 050 inch Lift:216

Exhaust Duration at 050 inch Lift:216

Duration at 050 inch Lift:216 int./216 exh.

Advertised Intake Duration:265

Advertised Exhaust Duration:265

Advertised Duration:265 int./265 exh.

Intake Valve Lift with Factory Rocker Arm Ratio:0.454 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio:0.454 in.

Valve Lift with Factory Rocker Arm Ratio:0.454 int./0.454 exh.

Lobe Separation (degrees):110
Click to expand...
 
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