Proposed cam specs

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bighammer

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Please tell me what you think about this cam.

I contacted a cam grinding company and gave them a description of my car ( 1970 Dart, 360 roller cam, Holley 600, Wieland intake, stock bottom end, stock Torque converter, 2 1/4 dual exhaust w/ turbo's) and its intended use (weekend cruiser with some muscle, street only)

They suggest 224/232 @ .050", 274/282 adv, .519"/.528" lift, 112 sep

I did not get to talk to them, this was done in an email, but I don't know how much different this cam is from the stock one. Any feedback?

Thanks
 
It's a bunch bigger than a stock cam, right on the edge of needing a looser torque converter. Should work good for what your wanting to do IMO... What company was it?
 
That's real close to my Crane roller. I'll be running a 2800 stall converter with it.
 
with those wide lobes it amost could be a good turbo cam....
 
A stock Hyd. cam is in the low 200's and rollers can be even lower than that due to less friction and up'd Efficentcy of it. You declined to give a gear ratio and tire size to use. This would be important!

Without that info, I'd have to still say it is a nice grind. Though IMO the missing info may change what MY opinion would be.
(AMA what I would choose for a cam.)
 
Interesting, thanks. The gears I have are 2.76, with 14 inch rubber. This is sounding like too much cam for me.
 
Do you have headers? With what you list, if you have headers I think it would be fine. A 360 is a longer stroke. 224° is nothing in one and after the pushrod angles given it'sa roller you're goign to lose .020 or more of lift on it.
 
I think anything above a .500 final lift sounds too high on a flat tappet, but as stated above, because of the roller tappet lifters, your pushrod geometry changes from the lifter to the rocker and you will shave something like .023" from the final lift.

If it were a flat tappet, I'd go with a 489 501 or something like that, but it sounds like it's a good lift number for a roller 360.

The duration of open to close on the lobes being in the 220 degree crank rotation should be ok with a 360 stroke, the lobe sep should help some from overlap of intake/ exhaust valves being open at the same time in the cycle some, but that's why headers are suggested above. Header's individual runner tubes will help scavenge the unburnt fuel back into the cylinder.

Sort of a double edged sword there. You can gain a little HP there, but you lose drivability and most good fitting headers that don't hang incredibly low are not cheap. I sort of leave them alone.

If you have manual steering and you aren't afraid of changing the exhaust up front, a pair of 360 Truck manifolds with rear dump are nice and they are inexpensive. Magnum manifolds well, too. I'm running truck manifolds with power steering, but I had to modify the bottom rear end of the manifold near the exit and shave a small amount from the cast iron on the steering box to give it a little more room, comfortably, but they work well and nothing touches. When the engine moves under stall, it moves further away from it and keeps it's distance.

I'm with Moper on this. Though I myself would like more gear. 3.21/3.23

I agree. No matter what, I think you should eventually plan on a 3.21 or 3.23 gear set for what you're going for. Don't bother spending cash on a sure-grip. Just find a good, used open carrier for an 8 1/4 with 3.21's or an 8 3/4 with 3.23's. Whichever axle you have. If you have a 7 1/4, just look for a complete 8 1/4 with 3.21's.

I think this cam is a good buy for you and will give you the opportunity to move up in gears to help your cruising/ acceleration. The gears down in the 2's help highway, but actually hurt MPG in town as well as power, due to the added throttle position needed and converter slipping to get the car moving.

I think you are on the right track here. I don't know what the primary size is on a 600 holley, but I wouldn't be surprised if you got more response and higher HP and TQ from something in the 625 range with smaller primaries for the street, but if you've already got the carb, run it.

Does the cam have any initial advance built into it? That can help some, too.
 
It will work well. Converter always helps, get the base idle tune up right and it will run well.

Not apples... Here's a build using some brodix, like ede's, and a comp XR268HR cam
http://www.forabodiesonly.com/mopar/showthread.php?t=225372

Pay attention to valve to piston clearance if sticking with stock slugs. It's not the dish that's an issue, it's the raised edges that will get you. Depending on static compression, I'd be putting that cam in around 106 ICL or even cut it on a tighter LSA to get the intake valve closed sooner.
 
Hmm, no headers, but I have purchased a pair of 340 manifolds... one side is 2 1/4 outlet, the other side is only 1 7/8. :-( Gonna have to find me another side (I forget which one i need) I wonder what size outlet is on the 360 truck manifolds? Sounds like it may be do-able with a little grinding, I have power steering, 8 3/4 rear.

The company is Oregon Cam Grinding, located in Vancouver, WA across the river from Portland.
 
the cam is a little overkill for the stock drivetrain, but it will work. it's costly for a roller lifter setup but if the engine is already set up for that it will work fine :D
 
Sell the smalll outlet manifold and find an earlier larger outlet one that matches. If it's the drivers side, they are not hard to find and fairly reasonable in cost. You might be able swap out at little or no cost.
 
As for too big on the converter,I have a Crower roller with 112 lobe centers,224@.050. 15 initial,34@3000 , on the distributor curve.Holley d.p./ air gap ,up top. Cold,idles like a stock 340 cam.Warmed up in drive.Smooth idle,21" of vacuum a 800.Don't worry about drivability on a stock converter.Set the dist .curve right.
 
Good info all around.

Hmm, no headers, but I have purchased a pair of 340 manifolds... one side is 2 1/4 outlet, the other side is only 1 7/8. :-( Gonna have to find me another side (I forget which one i need) I wonder what size outlet is on the 360 truck manifolds? Sounds like it may be do-able with a little grinding, I have power steering, 8 3/4 rear.

The company is Oregon Cam Grinding, located in Vancouver, WA across the river from Portland.

The truck manifolds that I'm running are '72 360, which are the same up through the late '70's, maybe '80's, before Magnum.

I'm seeing 2 1/4" outlets on both sides. The thing that I really like about the manifolds is that they do not raise on the driver's side, so they don't nuke spark plug wires, even without any heat shield and are easy to change plugs on, even warm.

I'll get some pictures (and numbers) of what I've done on mine, but I really like them for the street. The best thing you can do is get a set from a truck and cut the pipes where they start to go back, to use what you need for your exhaust. I managed to modify the clamp to clear the trans brace, but you could modify the brace as well to get it to clear.

It's just basic cutting and material grinding to gain clearances on the driver's side. The passenger's side was drop in.
 
Thanks all for the replies on my cam question. Very helpful. Cams are still pretty allusive to me.

DaveBonds, do you have pictures you could post? I think you should start a new thread as this topic has come up before, and if there are other 2 1/4 inch manifolds (other than the 340 ones) available, this would be good to know about.

On mine, it is the passenger side that I need to acquire to replace the 1 7/8" mis-matched one.
 
It'll be fine, the 112 lobe separation will definitely help keep it streetable.
 
Here you go-

Truck%20Manifold%20on%20A%20body%201.JPG


Truck%20Manifold%20on%20A%20body%202.JPG


The grinding that I did was initially experemental as I was looking for something to start a dual exhaust system with. I had two sets, one cracked so I started messing with it until I blew through it to see how far I could safely go. You can take a bit out of it, but I opted to modify the corner of the power steering case and manifold, as not to encroach on wall thickness on either one too much.

They have about 1/2" clearance between each other on crappy old spool type mounts. If I got new mounts, I'm sure they would sit even further apart, but they don't hit anywhere. The rust is from pressure washing and where I ground the cast colored paint from the steering box. Never mind the oil on the intake bolts, the entire upper half of the engine is coming apart soon for some mods (that I will be taking pics of for that thread) this weekend.

One thing you could do is shim your mounts a touch, as you have the early style mount, if it contacts. You can cut about 1/4" deep on the ridge of the manifold in a crescent and it should clear with plenty of wall left in the manifold. I also had to to take some superficial material from the bolt ears on the manifold to exhaust collar. For some reason, it wouldn't clear something. I think maybe the block, for some reason, but it was really minimal.

What I did to find out where to clearance the manifold and steering was take some colored grease paint, like a pastel or something that will transfer and coated the areas that I thought or knew looked close, then just removed material until I saw that the manifold wasn't marking anymore and had clearance for movement.

The engine rocks over to the right, away from the steering, so it doesn't hit.

The other modification that you can see is that I pulled the front and rear exhaust mount studs with some vice grips and replaced them with bolts. This was because I couldn't get the manifold over the studs with the engine in place around the steering box at the rear, so I had to slip it down in to place to put the bolts in, but that's not a big deal. The trick is to use a one piece gasket, get the front in and swing the back of the manifold and gasket to align for the bolt, then you can get the rest easy.

I also heat shielded the battery cable for the starter with some reflective insulating sleeve, down low that you can sort of see. The rear dump gets close to the cable, but isn't a heat issue on the starter. The trucks have more room to the firewall, so the cable isn't an issue on them, because they come over, further back.

The passenger side was a no-brainer, but would obviously require relocating your pipes to accomodate the rear dump.

Truck%20Manifold%20on%20A%20body%20passenger.JPG


Man, I can't wait until I get the new stuff on this engine and clean it up a bit.

Anyway, I hope this helps. I really like having them on the car, because it makes maintenance easy and gives better exhaust flow, without making me cringe over speed bumps and dips.
 
Great tutorial DaveBonds. Thanks for the info filled post. The pictures help too. Good luck with your project / upgrades this weekend.
 
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