Cams How do you choose one?

[rumblefish360]

I think the best answer is, it depends on what you're doing.

I'm not interested in getting every ounce of power out of it. Honestly, that's the way most people building street cars should look at it. If you try to pick a camshaft based on getting the last little bit of power per a given combo, you'll be forever chasing your tail.

More additional words of wisdom that should be included in your “Guide to Hot Rod Bliss” thread.

Oh so true.

 

[toolmanmike]

The problem with cams is everydoby has there own idea on what would be good. And as you have seen, so do the cam companies. Call them all back and re ask your question just so you’ll see that you’ll more than likely get different answers again even from the same companies.

This is not a scientific way of picking a cam but it will get you really close to what you want without racking your brain out.

Be honest in what you want from your car.

How do you want it to sound rhythm wise?
The lobe separation angle can largely be viewed like this.
116, smooth like melted butter
114 smooth
112 mild idle chop
110 typical muscle car
108 radical muscle car
106 racer
Anything lower, way radical

Pick the rpm you travel in. This is the duration of the cam. As a general guide, the cam companies have listed there basic rpm range. Though this Varys with many other factors that come into play, it is still generally an OK guide line. The cam companies generally list the ranges with the popular engine of what ever make they are. In our case, the 340 is the popular engine. You can raise the rpm band a few hundred RPMs because the engine is smaller. If it were a stroker, you can lower the rpm band down a few hundred because it is a bigger engine. For a driver, error on the smaller one, usually the next one down.

Lift. It helps to know how much the head flows at given lifts. For a street car, yield before max flow and lift.

Rate of lift of the cam lobe. Faster is better but also harder on valve springs. With that said, there is no crime in choosing a cam that doesn’t have the fast ramp rate. You’ll never feel the difference. Long life street cars have slow ramp rates.
Don’t fall for the old cliché bullshit of “That cam has Chevy lobes.”
The engine doesn’t know, you’ll never know, they’ll never know.
The car is a cruiser with fun every once in a while. Worry not!

Many people here will roast you for not following there thoughts and choosing a fast ramp, high lift, low centerline cam because your going to loose power. While they are correct, just what is it your building for YOURSELF!

To this end, if you asked me what you would like after reading your guide that you posted.....

A Hyd. cam from Crane;
1:
Crane Hydraulic Flat Tappet Camshafts 693511
2: (IIRC, I’ll check my cam card, the rpm band doesn’t start where Summit listed it at 2K but at 1500.)
Crane Hydraulic Flat Tappet Camshafts 693941

You'll never go wrong with the common sense approach to cam choice. Nicely done.

 

[rumblefish360]

Thanks Mike. I have used a verity of cams from super mild to hair raising wild from no name outfits to cam guru gods leading the way in technologies edge. The right cam for the right application is truly critical when racing. As you go down the pecking speed order, the less critical it becomes when you look to just ramp up the car for fun.

You can use science if ya like but it is to exact for a driver with just added pep to it. My basic approach is just simple common sense when you have working knowledge of how cams work, though I’ll never state I’m a guru at it. I’m just a backyard hot rodder who has read a bunch of articles from the fore front men in the field and has done a few things with a few buddies. ;)

 

[1965barr]

Thanks it should be simple to a point .yes a cruiser out of this I got a better set of heads more comp and now a cam. My problem is I never had to bye a cam even younger ,when I raced I had an engine builder , but this is fun learning , I took the day off today to go blow bubbles ran into a guy that still can’t figure out what cam to use lol.

 

[moper]

If you were dropping the engine off to me I'd say either the XE256 or XE 262. If you want to spend more order a custom unit, and I'd trust Jones or call Porter Racing Heads for Duane. He's only a stone's throw from the Canadian boarder.
IMO you can (and are almost to the point) of overthinking this. With the new heads, the compression will still be low for 3200' altitude life. Smaller will be better for you.

 

[Wyrmrider]

Great Thread
First reread post 14 and 19
then
"Seems like the recommended Bullet cam specs are very similar to the Summit 1789 , but with a hair more exhaust duration." post 71 Bullet is a much bigger cam- way too much duration for a low compression build- see my post above
BULLET, COMP, HOWARD, LUNATI measure their seat duration (.006) different than SUMMIT, CRANE, ELGIN (.004)
MOPAR Stock and MOPAR PERFORMANCE (and ENGLE) are different again somewhere around .008
Perhaps Crower could say where Crower measures theirs but I guarantee that a 267 Crower is bigger than a 276 Summit or Crane
and much bigger than the suggested 268 or 272 Cranes
Bullet and Howard (and Crower) need to know that you need a cam from their .904 list
why- to get a decent area under the curve while keeping great dynamic compression
BTW these are not Bracket Racer grinds you get more area due to the bigger lifter not because of a more radical grind
Have the machine shop cut the guides for a half inch lift will give you much more flexability also for Viton seals at the same time
Summit Cams were ground by Crane's detroit subsidiary- Even Crane Cams were mostly not ground in florida (same with all the big camgrinders)
let us know if you are going to change the heads/ compression- whole new ball game
No comp cams smaller than XE275HL you leave torque on the table The duration suggested are fine- it's the area under the lift curve that sucks

 

[1965barr]

Yes I’m going to use the Indy heads and thin gasket that’s what I meant by more comp. I think that will help a little . Damm elevation hurts .

 

[moper]

The boost in static, while measurable will not be of significant amount. But that's ok. The key is don't over cam it, and IMO the discussion of a few degrees and some idea that you're going to feel a huge difference between any of them is laughable. It's a mild street car. Put something designed after the 90s in it and go enjoy it.

 

[rumblefish360]

The boost in static, while measurable will not be of significant amount. But that's ok. The key is don't over cam it, and IMO the discussion of a few degrees and some idea that you're going to feel a huge difference between any of them is laughable. It's a mild street car. Put something designed after the 90s in it and go enjoy it.

That makes Two of us.

 

[Wyrmrider]

On comparing duration I just posted in the 65 Barracuda thread- worth a read
the stock 252 (in MOPAR degrees) 360 cam is 278 in Crane, Summit, Elgin degrees (.004) but a lot of that is in the super long closing ramps (which kills DCR- 340 cam is worse)

 

[nm9stheham]

I took the day off today to go blow bubbles ran into a guy that still can’t figure out what cam to use lol.

View attachment 1715238092

Made me really laugh at that one LOL

 

[Wyrmrider]

Really cracks me up Bubbles was Michael Jackson's chimp

 

[1965barr]

Just for fun I thought what the hell Ill phone in stead of texting,fun talking to the people at the cam company’s. Here are the results-
Comp. 262/270 ,110/106 ,218/224, .462/.470 porter racing if custom he would put it on 112 ICA 57. Overlap 46
“. 256/268, 110/106, 212/218, .447/.455. Comp. ICA 54 Ol 42
Howard255/261, 110/106, 208/214, .479/.494 Phone. ICA 51.5 Ol 38 .904
“. 265/273, 110/106, 218/226, .502/.525. 2nd choice phone. ICA 58.5 Ol49
“. 267/267, 110/106, 213/213, .450/.450. Text. ICA 59.5. Ol 47
Crane. 260/272 , 112/108, 204/216, .427/.454. Phoned ICA 58. Ol 42
VooDoo253/258, 112/108, 208/213, .454/.454. Text. ICA 54.5. Ol 31.5
“. 256/262, 112/108, 213/220, .454/.475 Phoned. ICA 56. Ol 35
Bullet. 267/270, 112/108, 214/220, .480/.489. Phoned. ICA 61.5 Ol 44.5on.904
“. 260/267, 112/108, 212/218, .444/455. Text. ICA 58 Ol 39.5 Same
Hughes 255/260, 113/109, 206/210, .473/.480. Phoned. ICA 56.5 Ol31.5 .904 for both
“. 260/268, 110/106, 210/216, .480/.495. Text. ICA 58 Ol 39.5. Both said they would like to see more compression for Hughes . Jones is on holidays till Monday
This is the Wallace results for my engine. Comp. 8.58-1. 3000’
ICA 49.5. Dcr 7.58. Dcp 136.5. VP. 128
50. 7.56. 136.12. 127
51.5. 7.50. 134.6. 125
54. 7.39. 132. 120
56. 7.29. 129. 116
58. 7.20. 126.5. 112
61.5. 7.03. 122.5. 105
47.5. 7.65. 138.46. 131. The best the motor will get.
That’s a sample ,I know this is a cruiser but trying to learn with this low compression motor to be ready for a high performance cruiser lol . Still trying to figure out under the lobe lol? I know this is figures and everything can be different in the real world . So if it was your motor what cam and why I ask so I can learn. Thanks g. Yes some of you picked really close that have said .

 

[nm9stheham]

I can tell you that you will feel/notice .25 point in DCR right off. It will show up in throttle response driving around. But won't go from doggie to blazing. More and more DCR will make it go more and more torquier at low RPM's.

All the DCR's above are at least higher than stock 318 so that is all good.

I personally like the Howard's 3rd on the list. Darned good lift for the duration. That all relates to the area under the curve.... you can have long duration and lower lift (but the later ICA hurts low RPM torque.....i.e., low DCR) or have high lift and low duration and less/no ill effects on the DCR.

I still laugh at that guy you ran into with the cam selection problem in post #79 LOL

BTW, the term you need to use is ICA (not ICL) which is the intake closing angle. ICL IS pertinent.... as is works into ICA. All of the numbers that you are getting from the manufacturers are probably with the cam installed 'straight up'.... i.e., with the timing chain sprockets installed 'dot-to-dot'. ICL (Intake center line) is the 2nd number in the number pair like '112/108' wiht the cam installed 'straight up'.

You can advance the cam's timing to something less for ICL, and that reduces the ICA by the same amount. I.e., advance the cam's ICL timing at installation by 4 degrees, like from 108 to 104 and then the ICA goes down by 4. Low RPM torque goes up (as does DCR) and the top end RPM peak HP goes to a lower RPM, and typically a bit lower peak HP. So playing with the installed ICL by advancing the cam is another thing to play with.

 

[dart19666]

Are those ground for Mopar lifters?

Yes

 

[1965barr]

Thanks for the reply nm9stheham it was very interesting to find all this new info out ,wow yes that Howard cam is probably the best for ICA That 49.5 is with 2 degrees advance,sorry for miss spelled I know it’s good to say the right thing and not confuse people or myself lol. But after reading the 360 motor articles lol, you know when you get a song in your head ,dam AJ I got his formula for ICA in my brain and can,t shake it lol. By the way really good information on cams.

 

[1965barr]

Hi talked to jones cams really good gentlemen and he said to run this for his cam-
256/264. 110/106, 202/208, .461/.499. ICA 54 overlap 40. @200/120. 256@.004
ICA 54. Dcr. 7.39. Dcp. 131.7. VP 120
50. 7.56. 136.12. 127
The Howard cam is
255/261. 110/106, 208/214, .479/.494. ICA 51.5. Overlap 38. @.200/128 255@.006
51.5. 7.50. 134.6. 125
49.5. 7.58. 136.5. 128
47.5. 7.65. 138.46. 131
These two cams are close questions when you install them 4 degrees advance do you lose rpms on top ? Does the overlap affect the idle (like lump)it’s when the valves are open right. And at @200 the bigger is that under the curve or degrees it at when at @200? Not trying to get technical or squeeze ever ounce out lol just trying to figure two cams out lol maybe I haven’t ask the right question,if I haven’t please fill me in Thanks. Added or should I ask which is better and why lol? When your at 106 do you want to advance to 104 or 102 or is that to low?

 

[dartgarth]

You are really splitting hairs between the cams. Usually they will tell you where to install the cam. Jones told me to install mine on 107 (or 2 degrease retarded from straight up as it is ground with 4 degrees advance already in it)

Some good reading here..

Camshaft Timing - Camshaft Theory - Circle Track Magazine

From the article.

"Advancing the cam timing moves the valve opening and closing events earlier in the cycle. Since the relationship between the intake and exhaust lobes cannot be changed, advancing or retarding a cam affects both the intake and exhaust valve equally. Also, the most important thing advancing or retarding a camshaft affects for engine power is when it closes the intake valve. For example, if the camshaft is advanced, the intake valve closes sooner. This typically increases cranking compression on a high-duration race cam. The result is more torque and power in the lower rpm ranges. But as the rpms increase, the velocity of the air/fuel charge in the intake ports also increases dramatically and the early intake valve closing hurts power.

On the other hand, if the camshaft is retarded, the intake valve will close later (usually sometime during the compression stroke). As you might expect, this drops cranking compression and hurts low-rpm power. But as rpm increases and cylinder filling is aided by the extreme velocity of the air/fuel charge in the ports, a retarded camshaft will help power. Usually, the change-either advancing or retarding-should be less than eight degrees. If you need to go more than that you should consider using a different cam."

Both those cams have 4 degrees of timing advance ground in from the numbers BTW (110/106).

Garth

 

[1965barr]

Thanks Dartgarth, Thanks for the article answer some of my questions and how to degree a cam. Jones did not tell me how to install ,not trying to split hairs lol just using these cams as a learning tool so when I put together a higher compression motor I can pick a cam for it or any other motor I have 3 motors to redo. Again thanks for your support g

 

[66fs]

Call Jim at Racer Brown. You have a 360 with aftermarket heads in a 65 Barracuda. The wheel wells are not wide so you are limited with traction. Anything around .450 to .500 lift and will do. The faster the ramps the greater the chance of wiping the cam, especially with light oil. It should easily go sideways when floored, even with the old 340 cam.

 

[furrystump]

I leave the cam choice to the really smart people, but I will not put a hyd cam in anything. Hyd lifters are such a crap shoot and the maintenance is over stated. Also if you are somewhat new to engine work. Adjusting the valves is a learning experience and a good opportunity to check the health of the valvetrain.

I always forget that people still run nonadjustable rockers. The cost to convert is definitely a factor to consider.

 

[j par]

(Edit to add: Oh yeah, I am just getting into the snowmobile thing at age 65 LOL)

Good gravy I had to erase a bunch to just quote this much LOL
I'd love to hear about your getting into snowmobiles? I have a thread on the general discussion snowmobile Blues...
Or maybe I'm brain dead and you've already made a comment.

 

[j par]

Just for fun I thought what the hell Ill phone in stead of texting,fun talking to the people at the cam company’s. Here are the results-
Comp. 262/270 ,110/106 ,218/224, .462/.470 porter racing if custom he would put it on 112 ICA 57. Overlap 46
“. 256/268, 110/106, 212/218, .447/.455. Comp. ICA 54 Ol 42
Howard255/261, 110/106, 208/214, .479/.494 Phone. ICA 51.5 Ol 38 .904
“. 265/273, 110/106, 218/226, .502/.525. 2nd choice phone. ICA 58.5 Ol49
“. 267/267, 110/106, 213/213, .450/.450. Text. ICA 59.5. Ol 47
Crane. 260/272 , 112/108, 204/216, .427/.454. Phoned ICA 58. Ol 42
VooDoo253/258, 112/108, 208/213, .454/.454. Text. ICA 54.5. Ol 31.5
“. 256/262, 112/108, 213/220, .454/.475 Phoned. ICA 56. Ol 35
Bullet. 267/270, 112/108, 214/220, .480/.489. Phoned. ICA 61.5 Ol 44.5on.904
“. 260/267, 112/108, 212/218, .444/455. Text. ICA 58 Ol 39.5 Same
Hughes 255/260, 113/109, 206/210, .473/.480. Phoned. ICA 56.5 Ol31.5 .904 for both
“. 260/268, 110/106, 210/216, .480/.495. Text. ICA 58 Ol 39.5. Both said they would like to see more compression for Hughes . Jones is on holidays till Monday
This is the Wallace results for my engine. Comp. 8.58-1. 3000’
ICA 49.5. Dcr 7.58. Dcp 136.5. VP. 128
50. 7.56. 136.12. 127
51.5. 7.50. 134.6. 125
54. 7.39. 132. 120
56. 7.29. 129. 116
58. 7.20. 126.5. 112
61.5. 7.03. 122.5. 105
47.5. 7.65. 138.46. 131. The best the motor will get.
That’s a sample ,I know this is a cruiser but trying to learn with this low compression motor to be ready for a high performance cruiser lol . Still trying to figure out under the lobe lol? I know this is figures and everything can be different in the real world . So if it was your motor what cam and why I ask so I can learn. Thanks g. Yes some of you picked really close that have said .

I had a purple performance cam that came in my first 318. I've had it reground twice into a solid lifter cam. Both times it was reground by Oregon cam grinding. As we get educated and more aware of lift, lobeseparation and duration it's these people we talked to that kind of fine tune our thinking of exactly where we want to be. I talked to Ken the owner of Oregon cam grinding based in Washington LOL. I recommended him a few times out here on the farm and lo and behold that's where people have got their cams from after that conversation with him. I'm saying all this so you definitely give him a call if you're given all these big names a call. You'll be talking to the man himself that grinds them and races them. My 2.

 

[famous bob]

I had a purple performance cam that came in my first 318. I've had it reground twice into a solid lifter cam. Both times it was reground by Oregon cam grinding. As we get educated and more aware of lift, lobeseparation and duration it's these people we talked to that kind of fine tune our thinking of exactly where we want to be. I talked to Ken the owner of Oregon cam grinding based in Washington LOL. I recommended him a few times out here on the farm and lo and behold that's where people have got their cams from after that conversation with him. I'm saying all this so you definitely give him a call if you're given all these big names a call. You'll be talking to the man himself that grinds them and races them. My 2.

I didn`t read all these posts, useless to know or wonder what someone else has bought or running in "their" car. Just match the cams power range or torque curve to your convertor, and what u want to do w/ it . Enough said already !

 

[j par]

I didn`t read all these posts, useless to know or wonder what someone else has bought or running in "their" car. Just match the cams power range or torque curve to your convertor, and what u want to do w/ it . Enough said already !

Enough said? Are you shutting me down ?