Please help with cam selection

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seventyswinger

seventyswinger

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Good day hopefully y’all can help me with my cam selection I have enough knowledge on what to buy but am not sure and don’t want to make the wrong selection. I was thinking of a hot street engine not daily driven raced occasionally.
360 bored .60 over zero deck height stock bottom end
Ootb Edelbrock heads 6077
Air gap intake
273 rockers
Holley 750 vacuum secondary
Factory distributor
904 trans 3500 stall converter
8 3/4 3.23 sure grip
This is what I have so far, hoping for 400-420ish hp. Please help been looking at so many numbers that now I’m lost. Thanks for any help.
 
Depending on the year 360 block you have, watch the .060 over. On the early blocks thru 74 I believe, It was the 340 with a 4.00 bore and you could do .060. Just my .02

Tim
 
As far as cam selection, your probably looking something in .500 lift and 280+ duration. There are smarter people than me better at calculating that. Im doing a 360 this spring for my 66 barracuda.
 
Never buy a cam based on advertised duration. Duration at .050, and if comparing 2 cams with the same duration at .050, look at the cams duration at other lifts to compare lobes.
 
ok
is the block already bored? if not bore as little as possible- strong trumps a few cu in
hows the crank
if you need crank grind and rods done and pistons get a stroker kit- keep the bore small
do you know the flow numbers for those heads- do not expect us to look them up
verify the heads cc's pistons cc for the valve notches, gasket cc and calculate your compression ratio what will your quenc distence turn out to be (quiz at 11)
what gas do you plan to use
whose pistons?
since you have the adjustble rockers and stock iron rockers are a good choice in your anticipated lift and rpm range I's put in a solid lifter cam for sure
roller tip rockers would buy you nothing and you would need to buy a B3 kit to make them follow any cam profile correctly
post back
what rev range do you want to drive
raising the cam duration can make more HP but can loose driveability, since you are not building a saturday night only or trailer queen
are you going to use the otb edelbrock springs- what are the ratings? I'm going to look them up
 
Wyrmrider said:
ok
is the block already bored? if not bore as little as possible- strong trumps a few cu in
hows the crank
if you need crank grind and rods done and pistons get a stroker kit- keep the bore small
do you know the flow numbers for those heads- do not expect us to look them up
verify the heads cc's pistons cc for the valve notches, gasket cc and calculate your compression ratio what will your quenc distence turn out to be (quiz at 11)
what gas do you plan to use
whose pistons?
since you have the adjustble rockers and stock iron rockers are a good choice in your anticipated lift and rpm range I's put in a solid lifter cam for sure
roller tip rockers would buy you nothing and you would need to buy a B3 kit to make them follow any cam profile correctly
post back
what rev range do you want to drive
raising the cam duration can make more HP but can loose driveability, since you are not building a saturday night only or trailer queen
are you going to use the otb edelbrock springs- what are the ratings? I'm going to look them up
Click to expand...
63cc chamber, up to .580 lift cam pump gas premium I also have access to 100 octane if needed the plan is to drive the car to local car shows and the occasional 1/8 mile run the valves on the head are stainless 202/160 with Hughes springs rev range 1800-5000ish

539928C9-A06F-487F-BE03-402AACD590E0.jpeg
 
Nothing magical just wanted a decent driver that’s not a dedicated race car. I think those number for me are realistic with the parts and budget I had in mind? I’m always open to opinions and suggestions I normally don’t post much on here but do value the knowledge of the people on this site , I live in south Florida so I get to also enjoy car shows year round.
 
A Seventy Swinger weighs about what? Say 3360 with you in in it . Maybe less.
At 420 hp, that is 8 pounds per hp and has the potential to go [email protected], in the quarter. That's pretty racy.
A zero-deck 360 with Eddies, comes in ,depending on the gasket at about 10.8 to 11.3Scr.
Any cam between 220* and 250* at .050 is fair game.
I have the samish engine and have run cams with 223,230,and 248 @.050s
My favorite was the 223.
With your stall and the 3.23s ,a 230 is about the biggest I'd go. Really, that 230 wants 3.73s with an auto, but 3.23s will work with that 3500.
The thing I see is that your combo will hit 60 mph at 6200 with 27s, still in first gear, spinning most of the way......, so a 248* cam would be a better choice...... if you had traction. But you could do the same thing with 300hp.Spin to 60 I mean, which is like the 220* cam. But then you wouldn't need the 3500TC.
Since it's not daily driven; and you do have the 3500, I might try a fast-rate, built for the 904 lifter, 230 to 235, Intake duration. That will make a pretty hot streeter. It's more than you need, but ........ it will be a lotta fun
And maybe not the best kind of fun;
I spent 5 years in a 70Swinger, with just a 340,and I got to know her nasty personality all too well. Changing lanes at peak torque in second gear with a 4-speed... could be risky business. I learned to be gentle on the throttle, which at age 17 to 22, was a real challenge,lol. You're going to need a lotta tire,both ends, else she'll be stepping out sideways on every turn, with just the slightest too much pedal. Thing is, the stock tubs IIRC can only accept 255s, and even that's a trick.
With your combo, any typical performance cam will run well. So I don't really see a wrong choice
For Eighth-Mile; my samish engine hit 93mph . If you get to that with 3.23s , that will be about 5600 at the top of second. A 232* cam is close to perfect for that.

Point and shoot, keep it straight, and Good luck
 
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AJ/FormS said:
A Seventy Swinger weighs about what? Say 3360 with you in in it . Maybe less.
At 420 hp, that is 8 pounds per hp and has the potential to go [email protected], in the quarter. That's pretty racy.
A zero-deck 360 with Eddies, comes in ,depending on the gasket at about 10.8 to 11.3Scr.
Any cam between 220* and 250* at .050 is fair game.
I have the samish engine and have run cams with 223,230,and 248 @.050s
My favorite was the 223.
With your stall and the 3.23s ,a 230 is about the biggest I'd go. Really, that 230 wants 3.73s with an auto, but 3.23s will work with that 3500.
The thing I see is that your combo will hit 60 mph at 6200 with 27s, still in first gear, spinning most of the way......, so a 248* cam would be a better choice...... if you had traction. But you could do the same thing with 300hp.Spin to 60 I mean, which is like the 220* cam. But then you wouldn't need the 3500TC.
Since it's not daily driven; and you do have the 3500, I might try a fast-rate, built for the 904 lifter, 230 to 235, Intake duration. That will make a pretty hot streeter. It's more than you need, but ........ it will be a lotta fun
And maybe not the best kind of fun;
I spent 5 years in a 70Swinger, with just a 340,and I got to know her nasty personality all too well. Changing lanes at peak torque in second gear with a 4-speed... could be risky business. I learned to be gentle on the throttle, which at age 17 to 22, was a real challenge,lol. You're going to need a lotta tire,both ends, else she'll be stepping out sideways on every turn, with just the slightest too much pedal. Thing is, the stock tubs IIRC can only accept 255s, and even that's a trick.
With your combo, any typical performance cam will run well. So I don't really see a wrong choice
For Eighth-Mile; my samish engine hit 93mph . If you get to that with 3.23s , that will be about 5600 at the top of second. A 232* cam is close to perfect for that.

Point and shoot, keep it straight, and Good luck
Click to expand...
Thank you very much for the assistance I forgot to mention it’s on a 73 duster 340 car didn’t wanna mess with the #’s matching motor , I also have installed the offset shackle kit and it’s got 275/60/15 under the rear. Was thinking about using the comp cam xe274h cam?
 
That should be the xe275hl should work or similar voodoo or Howards with 15 in the catalog notes column
still since you have the adjustable rockers I'd go solid lifters
fill this out and specify solid .904 lifter cam and emd lifters and spell out your spring specs, closed and open heights and pressures include the flows do not make people guess you can point to Aj's post which should be read yet again
you can send the details to other grinders such as lunati and racer brown or ultradyne, Engle, Crower (PM dart rep here on this forum)
It's luck of the draw on cam selection help from the big companies, Jones is good as is Crower and Engle and racer brown
,
 
seventyswinger said:
63cc chamber, up to .580 lift cam pump gas premium I also have access to 100 octane if needed the plan is to drive the car to local car shows and the occasional 1/8 mile run the valves on the head are stainless 202/160 with Hughes springs rev range 1800-5000ish

View attachment 1715438863
Click to expand...
Trying to ID those pistons.. got a PN?
 
AJ/FormS said:
What's magic about these numbers, for you?
Click to expand...

I'll tell you what is magical about them in my opinion. Modern V8 muscle cars make 425hp OOTB. So if you are running old school iron, I'd prefer to be in that ballpark.
 
nm9stheham said:
Trying to ID those pistons.. got a PN?
Click to expand...
Ditto! Not to be a jerk but I do not think your at a 11-1 ratio with those slugs. I run KB-107’s, a flattop with 5cc valve reliefs at zero deck, .039 head gasket (I forget the diameter) with an Edelbrock 63cc head and technically I’m not at 11-1. Close, but no actual cigar.

You have the same size, double mirror reliefs in those slugs. I see a much lower compression ratio. Sorry. I’m not trying to be a dick about this. But that is what I see.

With a 3500 stall, and 3.23’s on that tire, well, that’s a weird combo for me to see. I’d like to see some gear for torque release. At least 3.91’s.

The high stall allows a bigger cam but the 3.23’s kill any quick acceleration. It'll be a slug out of the hole. But it’ll have a bangin top end over a 100 mph. That’s for sure!

This makes cam size and choice a compromise. To that end, if it were I doing this, I myself would look at a Cams intake duration at around 230@050 at the largest until you come up with the actual static compression ratio.

Also, if you go with a off the shelf cam, I’d run a 1.6 rocker to get the cams action up and moving quicker. Most shelf cams are slow ramps even though they advertise them as quick.
 
A agree the 3.23's might be a bit tall.

The @.050 isn't the whole story. You can take a [email protected] cam and cut it with a tight LSA and it will build cranking compression and sound and act like a big cam. Or cut it on a wide LSA and it dociles out, but also drops CC. He wants a mild idle, but may not have the cranking compression to go big with a wide LSA. I also don't think you need crazy cranking compression. While it isn't necessarily ideal or text book perfect. My last combo was 160psi and ran just fine and was super street friendly. In contrast, my new engine has smaller chambers but a bigger cam. Still put out some big numbers with a decent idle and didn't have to be wound to the moon either.

I'd prefer a 1.5 rocker and get a cam with the lift I wanted but agree the 1.6 has it's place.
 
Like I said, if it were I doing this in the less than perfect/ideal set up, 230@050 is as big as I would go.The high stall is a potential problem for smaller cams. The same engines diltion above in the wife’s Cuda runs a 225@050 Hyd. roller and a 2500 stall converter with 3.55’s in a 26 inch tire. Designed to be a driver, not a street strip car. The combo works well.

The cam has mid .500’s for lift and I’m awaiting funds for a 1.6 rocker to take advantage of the ported heads which will show itself well on the top end. Most shelf cams could use a 1.6 rocker and IMO, even most street mills can use them. Is it needed? No.
roccodart440 said:
A agree the 3.23's might be a bit tall.

The @.050 isn't the whole story. You can take a [email protected] cam and cut it with a tight LSA and it will build cranking compression and sound and act like a big cam. Or cut it on a wide LSA and it dociles out, but also drops CC. He wants a mild idle, but may not have the cranking compression to go big with a wide LSA. I also don't think you need crazy cranking compression. While it isn't necessarily ideal or text book perfect. My last combo was 160psi and ran just fine and was super street friendly. In contrast, my new engine has smaller chambers but a bigger cam. Still put out some big numbers with a decent idle and didn't have to be wound to the moon either.

I'd prefer a 1.5 rocker and get a cam with the lift I wanted but agree the 1.6 has it's place.
Click to expand...
 
The biggest problem is that many people buy an off the shelf converter. Even if you buy a custom one, you really need a dyno sheet and the specs on the car to make it work properly. A convertor that actually flash stalls to 3500 behind a mild cammed car, is as you said, no good. You've most likely over shot the torque number, but maybe not, without a dyno sheet you are merely guessing and pissing the wind anyway.

Many people assume ported heads means more top end power or a higher RPM curve. This couldn't be farther from the truth. I just went from OOTB eddy rpms to max ported oversized valved eddy rpms, a ported single plane intake and a bigger roller cam. Peak power went up a whopping 100 (yes one hundred RPM). Power went up over 100 hp, tq went up 60ft/lbs. Another thing that surprised me is the carb, which was dialed for the engine prior to changes using an AFR didn't need to be changed at all jetting wise. Air bleeds needed some messing, but jetting didn't change.
 
roccodart440 said:
The biggest problem is that many people buy an off the shelf converter. Even if you buy a custom one, you really need a dyno sheet and the specs on the car to make it work properly. A convertor that actually flash stalls to 3500 behind a mild cammed car, is as you said, no good. You've most likely over shot the torque number, but maybe not, without a dyno sheet you are merely guessing and pissing the wind anyway.
Click to expand...
Very true!
Many people assume ported heads means more top end power or a higher RPM curve. This couldn't be farther from the truth. I just went from OOTB eddy rpms to max ported oversized valved eddy rpms, a ported single plane intake and a bigger roller cam. Peak power went up a whopping 100 (yes one hundred RPM). Power went up over 100 hp, tq went up 60ft/lbs. Another thing that surprised me is the carb, which was dialed for the engine prior to changes using an AFR didn't need to be changed at all jetting wise. Air bleeds needed some messing, but jetting didn't change.
Click to expand...
I’m not to surprised. I noticed a lot that perhaps you go up 1-2 jets sizes on a big change. As it is now, I’m starting to think a little differently as of late and think once the carb is dialed in, it’s kind of dialed into the CID more so than the components being used.
Still learning!
 
roccodart440 said:
The biggest problem is that many people buy an off the shelf converter. Even if you buy a custom one, you really need a dyno sheet and the specs on the car to make it work properly. A convertor that actually flash stalls to 3500 behind a mild cammed car, is as you said, no good. You've most likely over shot the torque number, but maybe not, without a dyno sheet you are merely guessing and pissing the wind anyway.

Many people assume ported heads means more top end power or a higher RPM curve. This couldn't be farther from the truth. I just went from OOTB eddy rpms to max ported oversized valved eddy rpms, a ported single plane intake and a bigger roller cam. Peak power went up a whopping 100 (yes one hundred RPM). Power went up over 100 hp, tq went up 60ft/lbs. Another thing that surprised me is the carb, which was dialed for the engine prior to changes using an AFR didn't need to be changed at all jetting wise. Air bleeds needed some messing, but jetting didn't change.
Click to expand...

On the money. Same with the carburetor needing almost no changes. Up the compression a point or 2 and see what happens...and what rpm did it peak?
What lsa?
 
Those pistons look like my sealed power hyp. 405cp. Mine are down .050 in the hole and have 10cc valve releifs. If so you at about 9 to 1 comp with a .039 gasket.
 
aaronk785 said:
Those pistons look like my sealed power hyp. 405cp. Mine are down .050 in the hole and have 10cc valve releifs. If so you at about 9 to 1 comp with a .039 gasket.
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And how big of combustion chamber?
 
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