A quick cam comparison

[scott657]

Are these a tossup for a 360, between 8 and 9 to 1 CR
Cam1
Engine Family: Chrysler 273-360 c.i. 8 Cylinder (1964-2002)
RPM Operating Range: 1,500-5,500
Grind Number:
Cam Type: Hydraulic Flat Tappet
Lifter Style: Hydraulic Flat Tappet
Camshaft Series: High Energy
Camshaft Gear Attachment: 1-Bolt
Usage: Street/Performance
Valve Springs Required: Yes
Camshaft Material: Cast Iron
California Proposition 65: WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov
Advertised Intake Duration: 268
Advertised Exhaust Duration: 268
Intake Duration at .050 Inch Lift: 218
Exhaust Duration at .050 Inch Lift: 218
Intake Valve Lift: 0.454
Exhaust Valve Lift: 0.454
Lobe Lift Intake: 0.302
Lobe Lift Exhaust: 0.302
Lobe Separation: 110
Intake Centerline: 106
Assembly Lubricant Included: Yes
Valve Timing @ 0.006 Lift:
Exhaust Close ATDC: 20
Exhaust Open BBDC: 68
spec-card-valve-timing
Intake Open BTDC: 28
Intake Close ABDC: 60

Cam2

 

[273]

Got decent gears like 3.55 or deeper and is it stock stall?

 

[scott657]

they will be 3.40 gears and probably 2500 stall

 

[273]

If it's between those two I'd go with the 1st, but I would look for dual pattern cam similar to the 1st.

 

[RustyRatRod]

I don't like either.

 

[273]

Lunati Voodoo Camshafts 10200700 Something like that or 701

 

[PRH]

The first cam looks like the Comp 268H, which I really like for these mild builds and sell pretty often.

I had a customer stop in yesterday with a fresh build.
Stock rebuild of a 70 340, but with later model 1.88 valve heads.
Stock 70 intake manifold, small Ede carb, shorty headers.
It’s in a 72 Scamp with auto and 3.23’s.

He’s had some other cars before, but I’m not sure how “hot” any of them were....... but he’s also got a 68 Charger that has a low cr 440 in it with a small cam and headers...... to use as a reference point.

The 340 in the Scamp got the 268H cam. Barely noticeable lope at idle, stock valve train was nice and quiet.
He was saying that he was surprised at how strong the motor felt, and that he was super happy with it.

 

[scott657]

The first is the comp HE268, the second is the Howards 710931, they look very close.
I'm wondering what would make one better than the other, is it valve events, duration , LSA, ICL?

 

[RustyRatRod]

The first is the comp HE268, the second is the Howards 710931, they look very close.
I'm wondering what would make one better than the other, is it valve events, duration , LSA, ICL?

Nothing. They both suck. A split pattern camshaft is far superior, IMO, especially for a mild build with factory heads. The exhaust needs the extra help of more lift and duration on the exhaust lobe. JMO.

 

[scott657]

OK, let me add something to the mix which will lead to something else. Edelbrock performer rpm heads OOTB 5767 valve springs.

 

[RustyRatRod]

OK, let me add something to the mix which will lead to something else. Edelbrock performer rpm heads OOTB 5767 valves.

Still needs exhaust help. Ported AND with headers, then you might could benefit from a single pattern......but the two you are speaking of now suddenly become incredibly SMALL. Like throwin a hot dog down a hallway small.

 

[scott657]

I love your quotes Rusty
"First, they choose a camshaft that's too "large" for their application. Second, they don't degree the camshaft. Make these two mistakes together, and you will have an engine that might sound good, but it won't pull a greasy string out of a cat's ***.

This is why you err on the small side. Have a stock 318 and want to re cam? Then it's probably best not to go over 220 degrees @ .050" lift. Considering that stock camshafts have a good bit less then 200* @ .050", going over .200 is an upgrade."
What duration @050 shouln't I go over for the 360

 

[RustyRatRod]

I love your quotes Rusty
"First, they choose a camshaft that's too "large" for their application. Second, they don't degree the camshaft. Make these two mistakes together, and you will have an engine that might sound good, but it won't pull a greasy string out of a cat's ***.

This is why you err on the small side. Have a stock 318 and want to re cam? Then it's probably best not to go over 220 degrees @ .050" lift. Considering that stock camshafts have a good bit less then 200* @ .050", going over .200 is an upgrade."
What duration @050 shouln't I go over for the 360

I don't know. "What all else" are you gonna have on it? You can make "a lot" of things "just work" simply by tuning this or that. For instance for a camshaft a bit "big" for a given combo, you can advance it down further. What's your whole recipe?

 

[scott657]

@PRH I know you like the xe268 and Have suggessted it wth my combo. that is what I am leaning toward. Just getting ready to hit the buy button. Also because I can use the components I already have. springs etc.

 

[scott657]

This will be my last cam post for this engine. I appreciate all the input.
1976 360 dont know how much in the hole
eddy performer rpm heads 63cc and intake
.039 head gasket
dougs 453 headers and full 2-1/2 exhaust
chrysler electronic ign with jeg 7500 box. I WILL recurve the ignition
stock 904, will add correct stall tc, ford 8"rear 3.40 posi.
3200# car.
Based on previous threads and questions the XE268 looks like my cam.
I'm not changing springs the

 

[PRH]

I’d say the XE268 is the better choice if you’ll be using the RPM heads.

 

[scott657]

Thank You.

 

[RustyRatRod]

I would go with one of the smaller VooDoo grinds. But......you've made your mind up so have at it!

 

[Wyrmrider]

I vote with rusty
If a choice between the two I'd go with howard but a size shorter
I never sold comp cams, why leave torqe on the table unless you just want the custoer to go nd not come back with warranty problems, as with all old school cams
and op
if you think those cams are anywhere near the same you need to ...

 

[AJ/FormS]

My 2cents.
At 2350ft elevation, you don't have nearly enough compression for either of those, and the gears and stall are gonna make you miserable.
From 268 advertised to 213/218 is a stinking long way, with 120psi cylinder pressure. Yur bottom end will come in like a stock 2bbl 273. and the 3.40 gears will keep the engine in the soft zone for what seems like an impossibly long time.
And the worse part for me is that the motor drinks gas like a 440.
My 2 cents
You know when those heads are gonna start working? Ima thinking ~50 mph in second gear.

If you really want to have some fun with 3.40 gears and a 2500TC, aluminum heads, and a 268 cam, then Ima thinking you need about 11/1 Scr, you know, like 340 territory, except higher because of your near 2350 foot altitude..

If you have to stick with the unverified 8.5Scr, then yur gonna need to close that intake a whole bunch sooner. Ima thinking Ica of 48*, and you will need it to be a solid lifter type

There is NO WAY I would put that together as outlined.
my 2 cents

Your engine is a prime candidate for KB-107s and an easy ~10.7Scr @.040 quench. And that combo with aluminum heads is good for 185psi on 87E10 gas@ 930ft(my combo,lol).

At 10.7 yer good for up to 64* Ica but better at 58/60. That is doable with a hydro, but I recommend a SFT. Now you can keep that 2500 and the 3.40s

 

[PRH]

I missed the elevation the OP lives at.

XE268 is gonna be a bit big for that combo at that elevation.

Drop down a size.

 

[volaredon]

both of those cams seem too close for me to decide between.... flip a coin, which is priced better, one has better warranty faster availability, things like that. I'm trying to figure out a good cam for a 318 myself right now.... my exp with that (at least here) seems like those responding want to put me into what seems like "way too big of a cam" for my combo and my expectations, Ive had bad experiences with cam swaps before.... cams that weren't supposed to be that "big" that wound up being all noise and no go. which has scared me on picking cams.

 

[PRH]

In most cases, when you’re undecided between two cams, and the overall theme of the build is on the mild side....... the safer choice is the smaller of the two.

 

[volaredon]

which again the 2 presented seem too close to pick either over the other unless someone can explain the numbers on each and break it down to me as to where the big difference between them lies/

 

[Wyrmrider]

whats the duration .006
what's the duration @.200
then compre the timig 2.006
smple as that
you can do it
area under the curve