Cam selection for a 66 383

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I was thinking of using this cam CL21-224-4 with the stealth heads.
I dont want to have interference problems with the L2315 flat top pistons.
The shop said I'll be ok but I need to verify everything.
Comp says 68 and up because different lifters. I read here if I go with the matching push rods I'll be ok. Is that 100%?

2024005.jpg
2024012.jpg

Comp suggests these springs for the cam: COMP Cams Valve Springs 911-16

2024013.jpg


Stealth list their spring pretty close:

2024014.jpg

Anyone care to help me choose I'm starting to get a bit overwhelmed.
 
I am also thinking of paying the extra $299USD for the stealth head Competition Valve Job
Should I do this and is there anything else I should ask them to do while they are at it?

thanks!
 
Cam selection -- The part that might be an issue is the gross valve lift. Use the valve lift of the old, original Chrysler Purple Shaft 284/284 cam as a guide. Might back-down the lift a bit with similar duration. There's also a Lunati cam that some in here have used in there 383/325 engines with no problems. It's more like a modern version of the Chrysler 383/440 HP cam. No issues with piston clearance. It might be a good option, too. Summit sells it as "their brand" at a good price.

Cyl Heads -- I know the Stealth heads tend to be a favorite in here. My research has indicated they are pretty much an aluminum version of the Chry 906 head. Perhaps with ports that can be played with a bit more? BUT the combustion chamber is still the old 1960s design. Not that that was bad, just that things have gotten better since then. As to efficiency and combustion dynamics improvements. Certainly, the Stealth heads appear to be a good bargain, compared to the Trick Flow heard and AFRs, or even the Edelbrock heads. Your judgment call.

In any event, get them checked-out, inspected, cleaned and oiled for installation when they are received. Do NOT consider them ready for installation when received. A Mopar Joe YT video on such, in general.

Valve job? IF they did a good job on the valve job to start with, no need for anything extra past a good 3-angle valve job. Also a part of the inspection activities of the cyl head disassembly/look see when they are received, prior to installation.

ALSO get the head bolts and pushrods recommended by the head manufacturer/seller! Ensuring the valve lifters and pushrods all match. PLUS head gaskets that will work well with an aluminum head! Usually Teflon coated, at least.

Personally, I would add full-roller rocker arms into the mix to take some friction out of the engine. Which means more horses at the flywheel. Or at least roller-tip rocker arms, for the same reason.

In general, valve spring pressures need to be "just enough" to get things done for the lift of the cam and rpm range. Heavier is good, to a point, especially on a flat tappet lifter. Roller lifters, not so much. Like the insurance commercial touts, get only what you need.

I suspect you've already got a quality double-roller timing chain set?

CBODY67
 
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Comp says 68 and up because different lifters. I read here if I go with the matching push rods I'll be ok. Is that 100%?
'67 and down used a different lifter and a push rod to match. The push rods are smaller on one end.

Last I knew, the early lifters aren't readily available, so it's a moot point.

The later lifters will work as long as you use the correct, later push rods.
 
Cam selection -- The part that might be an issue is the gross valve lift. Use the valve lift of the old, original Chrysler Purple Shaft 284/284 cam as a guide. Might back-down the lift a bit with similar duration. There's also a Lunati cam that some in here have used in there 383/325 engines with no problems. It's more like a modern version of the Chrysler 383/440 HP cam. No issues with piston clearance. It might be a good option, too. Summit sells it as "their brand" at a good price.

Cyl Heads -- I know the Stealth heads tend to be a favorite in here. My research has indicated they are pretty much an aluminum version of the Chry 906 head. Perhaps with ports that can be played with a bit more? BUT the combustion chamber is still the old 1960s design. Not that that was bad, just that things have gotten better since then. As to efficiency and combustion dynamics improvements. Certainly, the Stealth heads appear to be a good bargain, compared to the Trick Flow heard and AFRs, or even the Edelbrock heads. Your judgment call.

In any event, get them checked-out, inspected, cleaned and oiled for installation when they are received. Do NOT consider them ready for installation when received. A Mopar Joe YT video on such, in general.

Valve job? IF they did a good job on the valve job to start with, no need for anything extra past a good 3-angle valve job. Also a part of the inspection activities of the cyl head disassembly/look see when they are received, prior to installation.

ALSO get the head bolts and pushrods recommended by the head manufacturer/seller! Ensuring the valve lifters and pushrods all match. PLUS head gaskets that will work well with an aluminum head! Usually Teflon coated, at least.

Personally, I would add full-roller rocker arms into the mix to take some friction out of the engine. Which means more horses at the flywheel. Or at least roller-tip rocker arms, for the same reason.

In general, valve spring pressures need to be "just enough" to get things done for the lift of the cam and rpm range. Heavier is good, to a point, especially on a flat tappet lifter. Roller lifters, not so much. Like the insurance commercial touts, get only what you need.

I suspect you've already got a quality double-roller timing chain set?

CBODY67

Yes I agree the heads should be ready to go out of the box but I figure since everyone says they are not, I should use the service they have and get it done I'd guess.
I was hoping I tell them the cam and they would shim the seated height and such for that. I hope...
Detailed Description

While the typical "production" valve job work done on any mass produced head is fine for most applications, for those that want super accurate, very high precision work, we offer our competition valve job for our Stealth Aluminum cylinder heads. As you can see in the picture, we use only the best equipment, a genuine USA Made SUNNEN VGS-20 seat and guide machine. The tooling we use is the SGM series tooling, which is the strongest, most stable tooling offered, which assures the highest quality, most accurate and consistent results. For most applications, we cut a 30 degree top cut, a 45 degree seat, and a 60 degree throat cut. We keep a seat width of .060" for the intake seats and .080" for the exhaust seats, which works well for performance applications but is also very durable for street driving. After doing the work, we also hand lap each seat. This does two things, it allows us to visually verify with 100% certainty that the valve to seat contact has the correct position on the valve, width and concentricity, and most importantly it verifies the valve is making a good, tight seal to the cylinder head. AND, because we have to fully disassemble the cylinder head in order to do all this work, if you are upgrading to double valve springs and/or 10 degree locks and retainers, we will re-assemble the head with the upgraded components at no extra charge! That's a $100 savings. And, all the work is done right here at our shop in Carson City by Terry, who has had many years of machine shop experience under his belt. This allows us to keep all QC processes in house and and under our direct supervision and control. If you are ordering Steath heads (regular or CNC ported), simply add this part to your order and we will perform the work on the heads before they ship. In most cases, please allow 2-3 days time to complete the work.


I'm looking at these rockers.

2024015.jpg



I looks like I need to spend more on the spacers, hold down blocks, bolts and pedestal shims and the end caps.
The stock style look more convenient because the come with everything
 
I was thinking of using this cam CL21-224-4 with the stealth heads. I dont want to have interference problems with the L2315 flat top pistons. The shop said I'll be ok but I need to verify everything. Comp says 68 and up because different lifters. I read here if I go with the matching push rods I'll be ok. Is that 100%? View attachment 684650 View attachment 684649 Comp suggests these springs for the cam: COMP Cams Valve Springs 911-16 View attachment 684648 Stealth list their spring pretty close: View attachment 684647 Anyone care to help me choose I'm starting to get a bit overwhelmed.
Cam selection -- The part that might be an issue is the gross valve lift. Use the valve lift of the old, original Chrysler Purple Shaft 284/284 cam as a guide. Might back-down the lift a bit with similar duration. There's also a Lunati cam that some in here have used in there 383/325 engines with no problems. It's more like a modern version of the Chrysler 383/440 HP cam. No issues with piston clearance. It might be a good option, too. Summit sells it as "their brand" at a good price. Cyl Heads -- I know the Stealth heads tend to be a favorite in here. My research has indicated they are pretty much an aluminum version of the Chry 906 head. Perhaps with ports that can be played with a bit more? BUT the combustion chamber is still the old 1960s design. Not that that was bad, just that things have gotten better since then. As to efficiency and combustion dynamics improvements. Certainly, the Stealth heads appear to be a good bargain, compared to the Trick Flow heard and AFRs, or even the Edelbrock heads. Your judgment call. In any event, get them checked-out, inspected, cleaned and oiled for installation when they are received. Do NOT consider them ready for installation when received. A Mopar Joe YT video on such, in general. Valve job? IF they did a good job on the valve job to start with, no need for anything extra past a good 3-angle valve job. Also a part of the inspection activities of the cyl head disassembly/look see when they are received, prior to installation. ALSO get the head bolts and pushrods recommended by the head manufacturer/seller! Ensuring the valve lifters and pushrods all match. PLUS head gaskets that will work well with an aluminum head! Usually Teflon coated, at least. Personally, I would add full-roller rocker arms into the mix to take some friction out of the engine. Which means more horses at the flywheel. Or at least roller-tip rocker arms, for the same reason. In general, valve spring pressures need to be "just enough" to get things done for the lift of the cam and rpm range. Heavier is good, to a point, especially on a flat tappet lifter. Roller lifters, not so much. Like the insurance commercial touts, get only what you need. I suspect you've already got a quality double-roller timing chain set? CBODY67
 
I was thinking of using this cam CL21-224-4 with the stealth heads.
I dont want to have interference problems with the L2315 flat top pistons.
The shop said I'll be ok but I need to verify everything.
Comp says 68 and up because different lifters. I read here if I go with the matching push rods I'll be ok. Is that 100%?

View attachment 684650
View attachment 684649

Comp suggests these springs for the cam: COMP Cams Valve Springs 911-16

View attachment 684648


Stealth list their spring pretty close:

View attachment 684647

Anyone care to help me choose I'm starting to get a bit overwhelmed.

I am just final assembling an expensive build to one of my hotrods and I am using an aggressive flat tappet cam. This time, I decided to send the cam and lifters to Cam-King to break in the new cam on their machine. I received it back with the lifters numbered by cylinder and the break-in looks great. I will still do a standard 20 minute / 2,500 RPM break in just to be sure.

Here is the website: Cam-King: Reliable Camshaft Break-In Solution

Those of you with little to no experience installing a flat tappet cam would be wise to get help with break-in, pushrod and rocker arm geometry because bad things can happen if you don't do it right. Plus, using Chinesium rockers is risky. The valvetrain is not the place to save money!
 
I am also thinking of paying the extra $299USD for the stealth head Competition Valve Job
Should I do this and is there anything else I should ask them to do while they are at it?

thanks!
go with the promaxx heads if you are in the budget of the 440 source, better machine work and more valve spring options to fit your cam if you contact them
 
comp says 1.90 height.I bet the springs are 911 on the alum heads too. I am using the 911 springs and at 1.87 height they come in at 127 seat and 309 at .500 lift.
 
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I am leaning heavily towards building the 516 heads.
If places would broker this stuff it wouldn't be so bad but leaving it up to fedex I'm gonna get my a$$ handed to me. As much as I want some hot heads, I dont think in my case I'm gonna get to see the benefit. Its a tough decision. If it was 30-40 years ago I could see it but I'm having second thoughts.
are 516 with 1.74 exhaust that bad? I'm having a real hard time on this part of the build
 
The 1967 GTX 440/375 had closed chamber heads with 1.74" exhaust valves (the first year for 1.74 exh valves). Go for it.
 
I am leaning heavily towards building the 516 heads.
If places would broker this stuff it wouldn't be so bad but leaving it up to fedex I'm gonna get my a$$ handed to me. As much as I want some hot heads, I dont think in my case I'm gonna get to see the benefit. Its a tough decision. If it was 30-40 years ago I could see it but I'm having second thoughts.
are 516 with 1.74 exhaust that bad? I'm having a real hard time on this part of the build

Here is the cam setup I'm running in my '66 300 440 with 516 heads. Fantastic throttle response and really good power:

1728048131729.png
 
I am leaning heavily towards building the 516 heads.
If places would broker this stuff it wouldn't be so bad but leaving it up to fedex I'm gonna get my a$$ handed to me. As much as I want some hot heads, I dont think in my case I'm gonna get to see the benefit. Its a tough decision. If it was 30-40 years ago I could see it but I'm having second thoughts.
are 516 with 1.74 exhaust that bad? I'm having a real hard time on this part of the build
I am running 915 heads with the 1.60 exhaust valves pulls to 5200 rpms with no problem. and with a smaller 217-221 cam and 2.94 gears goes side ways off the line or even going 10 mph.
 
I am leaning heavily towards building the 516 heads.
If places would broker this stuff it wouldn't be so bad but leaving it up to fedex I'm gonna get my a$$ handed to me. As much as I want some hot heads, I dont think in my case I'm gonna get to see the benefit. Its a tough decision. If it was 30-40 years ago I could see it but I'm having second thoughts.
are 516 with 1.74 exhaust that bad? I'm having a real hard time on this part of the build
i would not put in the 1.74 valve unless your going to do some port work. get the best valve job you can and the right valve springs it will run good with the right cam. am running the 1.6 valve with a 446 engine you will only have 388.
 
I don't know. The picture isn't clear enough to discern the part number. Except for the cam specified by me, my machinist selected the rest of the valve train components.
i tried to read it could not. your cam i looked up 218-224 at .050
 
I don't know. The picture isn't clear enough to discern the part number. Except for the cam specified by me, my machinist selected the rest of the valve train components.
yes 218-224 on 110 LSA. 462-477 lift. extreme energy series. great street cam.
 
I am leaning heavily towards building the 516 heads.
If places would broker this stuff it wouldn't be so bad but leaving it up to fedex I'm gonna get my a$$ handed to me. As much as I want some hot heads, I dont think in my case I'm gonna get to see the benefit. Its a tough decision. If it was 30-40 years ago I could see it but I'm having second thoughts.
are 516 with 1.74 exhaust that bad? I'm having a real hard time on this part of the build
I think the cam you mentioned earlier is a bit big for a 383 and esp so with -516 heads.
But I'm not an expert, only a reader.

The 1967 GTX 440/375 had closed chamber heads with 1.74" exhaust valves (the first year for 1.74 exh valves). Go for it.
The -915 and -516 heads aren't comparable in terms of port flow, putting a 1.74 in a -516 won't make magic without port work.
 
I think the cam you mentioned earlier is a bit big for a 383 and esp so with -516 heads.
But I'm not an expert, only a reader.


The -915 and -516 heads aren't comparable in terms of port flow, putting a 1.74 in a -516 won't make magic without port work.
AGREED!, thats a decent size cam for your motor so if you dont get the heads, intake, exhaust, and carb to match the flow & fuel needs of that cam it's pointless to put one that size in. That's why the name brand companies started selling "power packs" back in the day with properly matched heads, intake, & cam to take the guess work out of it for the novice that wanted to get their money's worth on a basic power increase from their short block.
 
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