318 driver - cam change or not?

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That’s making me think of a crane solid a friend has in his stash last night. It’s a cam for a “someday” build, but only if “someday” includes a tunnel ram, heads that flow like a sewer, and e98 at the pump.
Crane Mechanical Flat Tappet Camshafts 690931 We I.D.’d it after I told him “We need the biggest cam you can find in your collection of stuff” for the 340 super trucker build. I had to eat those words!
 
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440 "six pack" cam - Page 2 - Don Terrill’s Speed-Talk 2015
some great quotes from Walter R. Malik
but you geta link to
Mopar stroker cam selection? Please help! - Don Terrill’s Speed-Talk 2007
with posts by UBHarold
Harold covers the waterfront on cams one size larger that...
The Short Voodoo or Jones work then a little longer on the seat is the Howard
One observation is that the 256 jones intake is larger at .200 than the 440 Magnum cam
so short seat - big at 200
anyone else find anything that meets YY1's repeated quest
move on
 
I've brought this up a couple of times here, but just because it may help the OP, I'll bring it up again. I don't have small-block Mopar experience, but my '65 Mustang with a 289 is probably similar to what the OP is trying to do. It's got 9:1 compression or so (I had a chamber CC'd at the machine shop). It might be 8.8 or 9.2. It has an Edelbrock 500 and a Weiand aluminum intake (the smaller one). It has 2.79 gears and a stock converter. It has dual 2.25 exhaust and stock manifolds. I run 15* initial, about 36* total (by 2300 or so), and about 8* vacuum advance.

I've tried both a Performer cam (204/214* @ .050, 280/290* advertised) and a Comp 252H (206* @ .050, 252* advertised). I could not tell the difference between the two. Idle was the same, low end torque felt the same, upper end pull felt the same, gas mileage was the same, idle vacuum was the same (18.5 in. in neutral, 14.5 in gear), and cranking compression was roughly the same (145-150 on a quick, one plug out test for both).

I'm running the Performer right now (probably a Melling grind...it has an "Engine Pro" label). I know this is anecdotal, but I haven't noticed that the long advertised duration has made any difference at all compared to the shorter advertised duration of the Comp cam. I think either cam would benefit from a slightly looser converter; mine drops 200-300 RPM from neutral to drive, but it did that with a stock cam and a worn out engine. Heck, it's done that for the 25 years and 85,000 miles I've been driving it.

Sorry to drone on about a Ford, but I can't imagine a 318 would be much different. Heck, it would probably be better because it has an extra 30 cubes. Mine never feels underpowered for a stockish engine, although I almost wish I would have stayed with a stock cam for gas mileage. Out on the highway all day, it will do 17 MPG, but any time I have to stop and go at all, it drops to 13 or 14. Once again, both cams were the same in that regard. Good luck to the OP!
 
Just FYI
My first Hughes cam was their 223@.050 that was advertised at 270/276/110; .008 tappet rise. They said it was a fast rate...... but at 47*/2 @ from advertised to .050, I don't know what's fast about that part. In any case, I sprung that cam with enough pressure to run 7000/7200 . It lasted over 40,000 miles and only puked because I changed oil one day with a brand that had the ZDDP reduced. It only ran for a few hours after that.
The next cam is a Hughes again, the next size bigger, and I put more spring on it. This time a 230@.050 advertised at 276/286/110. so 46*/2 this time. That cam now has over 60,000miles on it, and has been in there since fall of 2004.
The point is, too long.
I have been waiting several years for it to puke so I can change to a solid.
Ima thinking longevity of the cam is not gonna be an issue
PS; I use whatever oil is on sale, just adding a can of GM's version of ZDDP......Why GM?; just cuz I drive past the dealer once a week.
 
204-214 would be a big step backward with those gears- look at the seat duration
advance it or the 360 cam 4 degrees to get cyl pressure back and your gas mileage gets worse
op
take a look at the 318 cam thread stickie and find one with shorter seat duration and more lift
ps the 360 cam is also a step backwards
i'll t
post up your cranking compresson and let AJ run the numbers for you
273 at what checking height
lot of difference between a 260 crane and a 260 Mopar performnce
he's going to loose off the line with even a 256 comp
where he would also loose a little with a 256 lunati voodoo or the short howard he would make it up with the extra area
the 248 MP cam would be worth a look or find a later equilivant
still a lot of bucks
some say the best cam for a stock 318 is a stock 318 cam
here we are talking about stock gears and converter and compression
let's see if we can beat it all the way across OP's power band
Wouldn’t a whiplash camshaft bump up dynamic compression if you are concerned a 256 cam would lose energy?

No one mentioned milling the heads & intake to bump up compression either.

If he wants an upgrade, this has got to be better than a stock 318 camshaft.

A stock 318 from the mid 70’s was vey disappointing in a b body for me-4 cylinder cars were quicker.
 
Like most Teen owners we want more. A 4 barrel, some free flowing exhaust, and a recurved distributor will really make a difference. If you want more performance yet, a bigger cam is usually the next step. Because Teens are easy to over cam, you will probably have to add a high stall converter and/or a steeper rear gears to make it work. You spend most of your time driving around town between idle and say 3000 rpm. A bigger cam can make that Teen a dog, often worse than the stock cam. It depends on how far you want to go. Often times it makes more sense to keep the stock cam in there.
 
Like most Teen owners we want more. A 4 barrel, some free flowing exhaust, and a recurved distributor will really make a difference. If you want more performance yet, a bigger cam is usually the next step. Because Teens are easy to over cam, you will probably have to add a high stall converter and/or a steeper rear gears to make it work. You spend most of your time driving around town between idle and say 3000 rpm. A bigger cam can make that Teen a dog, often worse than the stock cam. It depends on how far you want to go. Often times it makes more sense to keep the stock cam in there.


Every time we talk about cam changes in low cr, high gear, stock stall etc... you got to choose conservatively, but don’t mean you can’t upgrade. There’s a ton of mild cam choices out there.
 
For comparison, here's an Elgin nearly stock heavy towing 318 regrind. Cam # RPM Range Valve Lift Adv. Dur. Dur. @ .050 OverLap LashHot Lobe Center Lifter #/ Cam Lifter Kit Smooth Stock Idle. Best Fuel Economy Cam. Good Choice for Heavy Towing. Spring Pressures - 95 lbs. On Seat - 240 lbs. Open E-983-P 1000-3200 Int .398 260 194 45 Hyd. 105 HL-2011 Exh .420 270 204 115 CL-983PK
And here's a stock replacement 318 Sealed Power camshaft.
Sealed Power Replacement Hydraulic Camshafts CS645
If your looking for the first baby step foot shuffle past the stock cam, the Elgin would probably be it. But I like the 204 cam installed at 4 degrees advanced better.
 
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Aaron
thanks for posting
The 204-214 is specced at .004 whearas the comp is at .006
so the 204-214 grind looks longer
there is some difference in the lca
they are both "universal" grinds"
both give up much area under the lift curve

On a thumper style cam
here the idea is to squeeze the lca to get the intake closed resonably early with a large intake lobe
however I do not know of one of these with an intake that closes at low 50 degrees at .006
most are larger- if you find one let us know
with a 256 @.006 lobe you really do not have to squeeze the lca that much to work
and as I posted above a modern 256 lobe can have the duration at .200 greater than a 220 Magnum lobe
.200 is what you want to watch for power - much better than .050

Garrett is that melling for a AMC-6?
anyway problem with advancing the 204-214 cam is that it opens the already early exhaust way early
AS UDHarlod posted 12 years ago the wide lca of the HP cam and the 204-214 was used to convert performance cams to smog cams - the wide lca - low overlap- reduces oxides of nitrogen
I think I posted the seat timing above or maybe in another tread
did you read the 318 cam stickie at the top of the forum
chers
 
It is and thank you for the heads up! Duly corrected, and the AMC grind is even more performance oriented than the grind posted.
 
For comparison, here's an Elgin nearly stock heavy towing 318 regrind. Cam # RPM Range Valve Lift Adv. Dur. Dur. @ .050 OverLap LashHot Lobe Center Lifter #/ Cam Lifter Kit Smooth Stock Idle. Best Fuel Economy Cam. Good Choice for Heavy Towing. Spring Pressures - 95 lbs. On Seat - 240 lbs. Open E-983-P 1000-3200 Int .398 260 194 45 Hyd. 105 HL-2011 Exh .420 270 204 115 CL-983PK
And here's a stock replacement 318 Sealed Power camshaft.
Sealed Power Replacement Hydraulic Camshafts CS645
If your looking for the first baby step foot shuffle past the stock cam, the Elgin would probably be it. But I like the 204 cam installed at 4 degrees advanced better.
I don't have stock cam specs handy but it's a lot of work to switch cams if the new cam isn't much bigger than stock.
 
The new link shows the specs for the stock replacement cam, it is .351/181 intake-.400/192 exhaust 109CL. Compare to an Elgin .398/194 Intake and a .420/204 exhaust on a 115 LSA. The base Edelbrock Performer camshaft is a .420/204 I/E on a 110 LSA on a 106 ICL. It works very well as package along with Performer Intake manifold, an Edelbrock 500 CFM, and Magnum manifolds on an otherwise bone stock 318 mid eighties 4X4 with 3.21 gears with 31X10.50 tires. If it makes a driveability and off idle torque improvement in that, I'm pretty sure it's good for a '73 duster, too.
 
...and now we're swapping in an entirely different valvetrain...


There has GOT to be a .42x-.44x hydraulic lift cam that doesn't have 300 degrees of duration that won't kill the low end, but will provide a decent boost in low and midrange power, and without killing MPG.

Yeah. I recommended one. And got trashed. lol
 
Like most Teen owners we want more. A 4 barrel, some free flowing exhaust, and a recurved distributor will really make a difference. If you want more performance yet, a bigger cam is usually the next step. Because Teens are easy to over cam, you will probably have to add a high stall converter and/or a steeper rear gears to make it work. You spend most of your time driving around town between idle and say 3000 rpm. A bigger cam can make that Teen a dog, often worse than the stock cam. It depends on how far you want to go. Often times it makes more sense to keep the stock cam in there.

I agree a lot of times. You'd be slap surprised what you can add by "supertuning". That's what we called it when I was in school. Spent many a night with friends' cars lined up in the driveway makin um faster and not addin any parts on some of um. lol
 
At this level of power, area under the curve...... how much horsepower, torque? 5-10-15-100?? Area under the curve may mean little to many in a case like this. Lets talk how much hp/tq in a case like this. Let’s speak English for the guy. Mile long burnouts or a baby chirp?

Under 3000 rpm power is hard to gain in a NA engine, adding displacement would be one of the main ways adding power down low. The trick is to add parts the don’t overly effect under 3000 rpm while gaining 3000-5500 rpm.

Don’t need tons of power to have a fun car 5.0 mustangs proved that. Adding a small cam should give the OP similar results.
 
I agree a lot of times. You'd be slap surprised what you can add by "supertuning". That's what we called it when I was in school. Spent many a night with friends' cars lined up in the driveway makin um faster and not addin any parts on some of um. lol
Flipping the air cleaner lid and call it good!
 
Under 3000 rpm power is hard to gain in a NA engine, adding displacement would be one of the main ways adding power down low. The trick is to add parts the don’t overly effect under 3000 rpm while gaining 3000-5500 rpm.

Don’t need tons of power to have a fun car 5.0 mustangs proved that. Adding a small cam should give the OP similar results.

Not if it's a stock smog era engine with crappy ignition and camshaft timing. If someone was just dead set against a cam change, but would yank the front cover, between advancing the cam and a hot ignition curve, I wouldn't be surprised at a 35HP change. That's power you can feel.
 
Not if it's a stock smog era engine with crappy ignition and camshaft timing. If someone was just dead set against a cam change, but would yank the front cover, between advancing the cam and a hot ignition curve, I wouldn't be surprised at a 35HP change. That's power you can feel.

True, but I think that should be the 1st step it to tune to get the best out of your combo, a good tune can be worth a bunch of hp.

But other than that it’s hard to build 30-50 plus hp over stock under 3000 rpm NA.

CR is another way but you can’t go to high before detention.
 
True, but I think that should be the 1st step it to tune to get the best out of your combo, a good tune can be worth a bunch of hp.

But other than that it’s hard to build 30-50 plus hp over stock under 3000 rpm NA.

CR is another way but you can’t go to high before detention.

I agree, which is why I lean towards the OP doing a cam change. He's already done all the rest.
 
I agree, which is why I lean towards the OP doing a cam change. He's already done all the rest.

true some people here are making a big deal over something that should be a pretty simple mod.
 
true some people here are making a big deal over something that should be a pretty simple mod.

Don't they always? Never seen anything like it.
 
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