Cam upgrade for my truck, '72 D200 with a 360

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MopaR&D

MopaR&D

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So I've had my 1972 D200 pickup for a couple years now and have been doing repairs and upgrades here and there. It has a 360 which so far I've replaced the heads with rebuilt late-70s pieces (stock heads were severely worn) and when the heads were off, the cylinders were in fantastic shape, no ridge to speak of and still some visible crosshatch. Forgot to measure the bores to check if it's been rebuilt though darn.

Anyway it's originally a 2-bbl engine I've upgraded with a Performer intake and 600-cfm Edelbrock carb, Hedman 1-5/8" longtube headers into 2-1/4" true dual exhaust and a simple Pertronix Ignitor I module so I don't have to deal with points (yes I know how to maintain them but the replacement parts are junk OOTB). It runs great as-is, the truck isn't light at around 4600 lbs with me in it so it's clearly no "muscle truck" but being a power fiend I'm considering doing a cam swap. I also get the feeling this stock cam with almost 130k miles on it has some wear as the engine doesn't run quite as smooth as other SBMs I've had even after going through the entire top end and super-tuning it getting the timing and jetting dialed in.

I'm wondering if it's possible to go to a slightly bigger cam without losing that crucial off-idle grunt to get this truck moving? I've used a Lunati Voodoo cam in the past with great results and thought about going with this one: Voodoo Hydraulic Flat Tappet Cam - Chrysler 273-360 253/258 Advertised Duration (Int/Exh): 253/258 ;Duration @ .050 (Int/Exh): 208/213 ;Gross Valve Lift (Int/Exh): .454/.454 ;LSA/ICL: 112/108 ;Valve Lash (Int/Exh): Hyd/Hyd ;RPM Range: idle-5000

My thinking is the advertised duration (not really a standard to go off, I know) is about the same as the stock 2-bbl cam but with more duration at .050" lift and much higher overall lift with undoubtedly better lobe profile. I really just want to at least retain (or increase if I'm lucky) the off-idle grunt but have more mid-range torque and not run out of breath at 4000 RPM. The truck has a HD 727 trans with stock converter (I assume the larger 12" unit by how tight it is and how low the stall speed is) and 3.55 gears with 33" tires so it needs as much grunt as it can get. Also not keen on using a factory 4-bbl cam, I'd like to take advantage of modern cam technology not just go up in size on the same lobe design.
 
I can't remember the PN but when I went through my '72 W200 360 years ago I put a DC RV cam in it. Never again. The engine has gobs of bottom end torque. On a warm day, with a warm engine, on level ground I can put it in 4th and pull away from a stop sign without a problem. But by about 4,000 rpm, it's all over. I'm going through the engine again this year and that is one of the first things to be changed. To what, I don't know, but it's getting changed.
 
FBO carries Racer Brown. A better cam for mopars. They will steer you in a better direction for the cam you need.
 
That first post I shared for a cam plays well with the stock converter. This is another choice that is very similar to the comp 268 high energy we installed in the low compression 360. It would work well for more mid power in your truck.
Howards Cams, Hydraulic Flat Tappet Camshaft & Lifter Set, Chrysler SB, 215/215 @ .050, .455/.455, 112 LS-Competition Products
But if you’re able to find a custom grinder with cores in stock, that is the better way to go. Don at FBO would definitely get you into something that would be much better than all the options I listed.
 
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Summit 6900 in 204 @.050 lift 421 ex 214 @.050 lift 444
summit 1789 in and ex 216 @.050 lift 454
 
I had a '87 D250 with 16"x 31" tires and 3.55 gears (9.25" 8 lug) with a 360 and I ran the MoPar 260/268* .430/.450" 110*LSA cam in it and it was very strong from idle to highway towing. This was in the mid-90s and at a free Snap-On Tools drag day at Commerce, Ga. NHRA strip I weighed the truck (5400lbs with me aboard) and I soundly trounced a early-90s Ford Lightning SVO 5.8L sport truck that same day. Got a best of 15mpg like all my 360s-lol-on the highway, about 10-11 around town, with a 625 Carter CS AFB. I have used the 272 Crane (Cam Dynamics) Energizer, .454" lift 110*LSA with similar results and a choppier idle, as posted you can get this same grind "white box" from Summit/Jegs/Elgin/etc. for less $$$.
 
Garrett Ellison said:
That is a good grind for your application if you can find it in stock anywhere at the present. What is your cranking compression at the present?
Personally, I would look into running this setup based on my present experiences with a cam upgrade in a very heavy truck with a low compression 360.
DODGE COMP Cams K20-221-3 COMP Cams Xtreme Energy Cam and Lifter Kits | Summit Racing
Click to expand...

I ran the Voodoo cam with the same advertised duration as this it's basically one "step" above the smallest which is the one I linked. That was first in a tired 1970 318 which was the original engine in my Duster then in a 10.5:1 360 Magnum in the same car, bad combo in the latter case gave too much cylinder pressure (pinged a lot/ran hot when pushed). One important consideration is that I'm at 5000' elevation so cylinder pressure is a luxury, so to speak. I did check the cranking compression a while back but I don't remember the numbers I'll have to do it again.

What was the performance change like in your truck when you changed to that Comp cam? Would you say there's any benefit to the stock cam or was it pretty much an improvement across the board?
 
Many here mention calling a cam company, but depending on the company you call you best have some names of people there and ask to speak to them. Don't just spill your guts to whoever picks up the phone, unless it’s one of the smaller operations. Of all the places I called and talked to someone I have to say the most enlightening person, where I knew I was getting the best insight, advice and education was from calling Bullet, speaking to Tim Goolsby. Many here mention talking to such and such at whatever company. Call and ask for that person. It’s sorta like going to the hospital. Don’t want no intern, don’t want no trainee or newbie learning or practice on me, give me Grandma, someone who’s been at it forever. Not saying it’s like that everywhere, but have some control, as much as possible, over who recommends you a cam
 
Flat out your cam lobe peaks have worn down and your lifters are also cupped because of it too. So getting back to your stock grind numbers will be a big improvement and it will run nice again too.

Melling SPD-22
Lift 430 / 444
Duration 276 /279

Good Replacement Cam.

☆☆☆☆☆

Worn 360 original cam,
lobes are wearing down.
Can expand up this picture to view.
20210610_125741.jpg


Replaced with the Melling SPD-22 cam
Running Very Nice, all around.

20210629_184634.jpg


Best to use the Melling lifters with the new Melling SPD-22 cam so you don't have a lifter failure at cam break in.
20210702_140822.jpg
 
Hi R D , I believe you got a cam from Jim D. I would phone him again . I got one for the low comp 360 it was EH -71 grind 262 ,214 lift 108 in at 105 ,.450 lift used.027 gaskets worked good for what it was . Buddy put in his tow rig excellent gas mileage and good torque till around 5000 rpm I got the same results but car was a lot lighter haha
 
1965barr said:
Hi R D , I believe you got a cam from Jim D. I would phone him again . I got one for the low comp 360 it was EH -71 grind 262 ,214 lift 108 in at 105 ,.450 lift used.027 gaskets worked good for what it was . Buddy put in his tow rig excellent gas mileage and good torque till around 5000 rpm I got the same results but car was a lot lighter haha
Click to expand...

That's true I did, it did cross my mind to hit him up again he ground the hydraulic roller cam for the 5.9L Magnum in my Duster which runs excellent. Thought about the longer lead times and slightly higher cost but might still be worth it...
 
12many said:
Many here mention calling a cam company, but depending on the company you call you best have some names of people there and ask to speak to them. Don't just spill your guts to whoever picks up the phone, unless it’s one of the smaller operations. Of all the places I called and talked to someone I have to say the most enlightening person, where I knew I was getting the best insight, advice and education was from calling Bullet, speaking to Tim Goolsby. Many here mention talking to such and such at whatever company. Call and ask for that person. It’s sorta like going to the hospital. Don’t want no intern, don’t want no trainee or newbie learning or practice on me, give me Grandma, someone who’s been at it forever. Not saying it’s like that everywhere, but have some control, as much as possible, over who recommends you a cam
Click to expand...

Yeah if I call a cam company for a recommendation or custom grind it'll be one of the smaller operations like Racer Brown, Oregon or a couple others I can't remember off the top of my head. You can call a big company with the same question multiple times and get multiple different recommendations because you aren't talking to the same person or at least someone with consistent knowledge each time.
 
Several of the ones listed would do fine.I would say something along the lines of the comp 260 HE grind or the 252 if they still make it.
 
I have to agree I really like the 260 HE grind here. That would have probably been a better choice for the fresh 360 in the W300 had it not been for the 4.88 gears with 33 inch tires. But look no farther than the spec page for what it's designed for. The 56 degree intake closing event helps maintain low rpm cylinder pressure, which is where the typical 360 truck engine needs the most help.
DODGE COMP Cams CL20-210-2 COMP Cams High Energy Cam and Lifter Kits | Summit Racing
High Energy 212/212 Hydraulic Flat Cam for Chrysler 273-360
 
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So plugging in some numbers in online calculators, it looks like the Lunati cam I linked actually has slightly earlier IVC point than the stock 2-bbl cam just based on advertised duration numbers I could find (and assuming LSA and ICL of 112???). I do understand the importance of keeping that number low to maximize cylinder pressure with stock low compression.

My other question is regarding lifters, I watched Uncle Tony's video about flat tappet lifters and how to check the face for having the correct crown. From what I can tell, all the lifters sold by the bigger cam companies come from the same supplier and it can be hit-or-miss on quality. Has anyone bought a flat-tappet cam and lifters recently and had any issues? What brand(s) did you go with? I'm leaning towards just getting lifters that come in a cam & lifter kit from the same company and check them carefully with a mic and a flat pane of glass, usually it's part of their warranty to use their specified lifters in case a lobe/lifter gets boogered during break-in. If any are out of spec I'll take pics and either send back for replacement or look at other options. Not really trying to spend $400 on a set of Hylift-Johnsons for a truck engine.

FWIW the Voodoo cam I ran previously I installed and broke-in in 2009 with Lunati hydraulic lifters from a kit, lasted 25,000-odd miles in 2 engines with no failures. It was still even in decent shape when I pulled it from the last engine but decided to toss it due to mileage and it did have slight visible wear on the lobes.
 
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Yup, hit & miss with today's FT lifters, made from pure crapanium. If you want reliable lifters, have a factory set re-faced & they are then as good as new. We have been doing that here for DECADES because of the high cost of new lifters.
 
So far, we've been lucky on the 268 H comp cam and lifter kit, about 3 months in and no problems with heavy duty tow and haul truck use. But we did also have a set of fresh heads with new valve springs set at the same specs as the comp 901-16 valve springs.
 
Wiki says Ft.Collins is at 1525m/ 5000ft elevation.
If that is true, then;
IMO,
That's a really big problem right there. A bigger cam will with a later than stock ICA, and Stock compression ratio, will be a HUGE disappointment. 8/1 Scr is not gonna cut it.
The next biggest problems,
IMO,
are the; 3.55s/33s/ and stock stall.
Those are a really big problem. The bigger cam with the later closing intake, will just make things worse; IMO forget the cam swap. Your cylinder pressure is already sadly lacking, why make it even worse.

Your new cam, with no other changes, will START to wake up in the range of 3200 to 3600. That maths out to 36 to 41 mph.
A lil below that range the power is likely to be LESS than it currently is. At the stock stall to say 2800, the power WILL be less, not may be.

Your first go-to for this sad situation, is stall. Yur gonna have to do it anyway with a bigger cam so just do it first.
Your Second go-to is gears; Yur gonna have to change them anyway after the new cam is in, so you might as well just do it first.
With those 33" tires, you need 15 to 20% more rear gear, say 4.30s; and at least a 2800 stall.
This will get you something like 30% more torque multiplication at zero mph, something no cam, can ever make happen, with no other changes. The stall will keep working for you out to about the torque peak, and the gears will never quit working for you.
But
A 110LSA HFTcam, in the range you are shopping in, will only work for you over a very narrow rpm range, maybe 1500 to 1800 rpm. And when you pull the 1-2 shift, with the factory TC/3.55s, the rpm will fall right off the cam, and there you are stuck in la-la land again, until the cam wakes up at say 4000 rpm/Second gear/70mph. But with your very low cylinder pressure, she'll just make a lotta noise.
Your 33s are making the 3.55s feel like 2.85s with 26.5 tires Those gears are keeping your engine at low rpm forever...... and your stock stall is just not pulling.
Until you fix your pressure-shortage, I recommend 4.30s for 33s; 65mph~2850 at zero-slip, perhaps 2960 on the tach. Those 4.30s with 33s will feel like 3.45s with 26.5s would.

If you have to keep the 33s/3.55s, then you have to fix your pressure problem first, and yur still gonna need a higher-stall TC.

Or you could just go BB, which at 5000ft, is what I would do.

Sorry but at 5000ft elevation, these are my opinions.

I know you only asked for an opinion on a cam upgrade, but I call it like I see it.
 
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AJ/FormS said:
Wiki says Ft.Collins is at 1525m/ 5000ft elevation.
If that is true, then;
IMO,
That's a really big problem right there. A bigger cam will with a later than stock ICA, and Stock compression ratio, will be a HUGE disappointment. 8/1 Scr is not gonna cut it.
The next biggest problems,
IMO,
are the; 3.55s/33s/ and stock stall.
Those are a really big problem. The bigger cam with the later closing intake, will just make things worse; IMO forget the cam swap. Your cylinder pressure is already sadly lacking, why make it even worse.

Your new cam, with no other changes, will START to wake up in the range of 3200 to 3600. That maths out to 36 to 41 mph.
A lil below that range the power is likely to be LESS than it currently is. At the stock stall to say 2800, the power WILL be less, not may be.

Your first go-to for this sad situation, is stall. Yur gonna have to do it anyway with a bigger cam so just do it first.
Your Second go-to is gears; Yur gonna have to change them anyway after the new cam is in, so you might as well just do it first.
With those 33" tires, you need 15 to 20% more rear gear, say 4.30s; and at least a 2800 stall.
This will get you something like 30% more torque multiplication at zero mph, something no cam, can ever make happen, with no other changes. The stall will keep working for you out to about the torque peak, and the gears will never quit working for you.
But
A 110LSA HFTcam, in the range you are shopping in, will only work for you over a very narrow rpm range, maybe 1500 to 1800 rpm. And when you pull the 1-2 shift, with the factory TC/3.55s, the rpm will fall right off the cam, and there you are stuck in la-la land again, until the cam wakes up at say 4000 rpm/Second gear/70mph. But with your very low cylinder pressure, she'll just make a lotta noise.
Your 33s are making the 3.55s feel like 2.85s with 26.5 tires Those gears are keeping your engine at low rpm forever...... and your stock stall is just not pulling.
Until you fix your pressure-shortage, I recommend 4.30s for 33s; 65mph~2850 at zero-slip, perhaps 2960 on the tach. Those 4.30s with 33s will feel like 3.45s with 26.5s would.

If you have to keep the 33s/3.55s, then you have to fix your pressure problem first, and yur still gonna need a higher-stall TC.

Or you could just go BB, which at 5000ft, is what I would do.

Sorry but at 5000ft elevation, these are my opinions.

I know you only asked for an opinion on a cam upgrade, but I call it like I see it.
Click to expand...

It runs surprisingly well for the altitude and low compression in a 4600-lb truck with tall-ish gearing; really gets up and goes from a stop, 0-60 is under 10 seconds. So you're saying there's no possible modern cam profile that can retain any level of bottom-end torque the way a 50+ year old economy cam profile can? Like I said in post #18, the cam I have my eye on has basically the same advertised duration as a 360 2-bbl and since it's ground advanced 4* it has an even earlier IVC event than stock.

I want to swap the cam and lifters as a maintenance job since this is the original engine to the truck from 1972 with 128,000 miles but I feel like just putting in another factory replacement 2-bbl or 4-bbl 360 cam would be a waste of time. If I'm going to go through the trouble I want it to be better, and not just a few HP from having not-worn cam lobes.
 
Well if your factory cam is worn out, (not likely at 128,000 miles in a big heavy4400# truck that goes zero to 60 in under 10 seconds,at 5000ft, strapped with the equivalent of 2.85 gears/6.98 starter gear);
then sure, you can better your power without loosing bottom end. But like I said, the power will be further up the rpm-band which is further up in roadspeed. To maintain the low-end power, your replacement cam only needs to close the intakes at or about the same time as the factory cam.
The best way to do this, is to start with a SOLID lifter cam, with which you can control the closing point by valvelash adjustment. Usually, the solid will have more .050 duration from valve closed, than a Hydro.
Typically, a hydro will have ramps from .006/.008 (usually called the advertised) lifter rise, to .050, of about 46 degrees. Few are less than .044. Many are more than 46*.
Furthermore, many hydros from .006/.008 to actually closed can be many many many more degrees. This has very little effect once the revs are up. But ........... with the equivalent of 2.81 gears and a stock stall, at what roadspeed does your engine come out of this? IDK.
Furthermore, many hydros are lazy on the .050 to .200.. With your combo, and your desire for power, you cannot afford to give anything up.

Now, A solid does not suffer from those limitations, because you set the opening and closing points with the adjustable valve lash. And since there is no hydraulic chamber to worry about, and the solid lifter is so much lighter, the rate of lift can be increased and so can the actual lift.
Normally, this type of cam can increase your power over the nose, without stealing pressure from the bottom-end. But in your case, at 5000 ft, if you're sharp, you have realized that this type of cam can be used to make the same power over the nose as the current cam does, but you can use it to increase your cylinder pressure and thus pick up power at low rpm.
Unfortunately, I don't think you will find an off-the-shelf, small-enough, solid lifter cam, to meet your needs. The theory is good, but I think that you will need a custom cam. by the time you get that done AND purchased/installed the adjustable gear, you could be close to the price of just installing hi-compression pistons, which is what your combo needs, and the which, will annihilate the weiner solid cam, with the 2bbl factory cam. At 5000 ft, pressure is or should be, your primary concern.
The Wallace calculator predicts your 2bbl cam (Ica of 56*) equipped 360 to currently make about 107psi@5000ft elevation. And the low-rpm power (below 3000/3500) is barely better than a factory stock 225 slanty at sealevel.
Performance starts at 130psi but doesn't really wake up until 140/145, and the best power will be achieved after 155psi. So as you can see, at 107 you cannot afford to give any pressure away.
If you had a 3400 stall or something, your pressure would be less of a concern, but 107psi is still pitiful.
Lets say the solid lifter cam has a 4 degree earlier closing intake, (now 52*); that will bring the pressure up to only 111psi.
But lets say you keep the 2-bbl cam and increase the compression ratio to 10.3. That would jump the pressure to 156psi@5000ft; A far greater power gain because it starts at idle/ zero mph.

As for me; I would not waste my time/money with camming this combo, with no other changes. So what! if you pick up 15 hp at 4600rpm; with your gears that doesn't show up until , ......... wait for it............. 48 mph. If the power march begins at 2hp@3400 rpm, that would be 34mph.

If anything, I would put a 3000TC on it and pick up say 40 ftlbs at 3000=23hp at ZERO mph; now that's what your combo needs. Ok well besides more compression,lol.
But to answer your question;
yes, it is possible to make more power over the nose without giving pressure/much pressure, away at the bottom-end.
But for less money spent, the TC will make you way happier.
Compare the cost of a solid-lifter cam and kit, plus adjustable valve gear, delivered and installed;
to the cost of a TC, delivered and installed.
Then compare guessing 12/15hp at 4600/48mph (one cam size bigger);
to guessing 23hp at zero-mph; (3000stall compared to 2200).
I know what I would do.
 
AJ/FormS said:
Well if your factory cam is worn out, (not likely at 128,000 miles in a big heavy4400# truck that goes zero to 60 in under 10 seconds,at 5000ft, strapped with the equivalent of 2.85 gears/6.98 starter gear);
then sure, you can better your power without loosing bottom end. But like I said, the power will be further up the rpm-band which is further up in roadspeed. To maintain the low-end power, your replacement cam only needs to close the intakes at or about the same time as the factory cam.
The best way to do this, is to start with a SOLID lifter cam, with which you can control the closing point by valvelash adjustment. Usually, the solid will have more .050 duration from valve closed, than a Hydro.
Typically, a hydro will have ramps from .006/.008 (usually called the advertised) lifter rise, to .050, of about 46 degrees. Few are less than .044. Many are more than 46*.
Furthermore, many hydros from .006/.008 to actually closed can be many many many more degrees. This has very little effect once the revs are up. But ........... with the equivalent of 2.81 gears and a stock stall, at what roadspeed does your engine come out of this? IDK.
Furthermore, many hydros are lazy on the .050 to .200.. With your combo, and your desire for power, you cannot afford to give anything up.

Now, A solid does not suffer from those limitations, because you set the opening and closing points with the adjustable valve lash. And since there is no hydraulic chamber to worry about, and the solid lifter is so much lighter, the rate of lift can be increased and so can the actual lift.
Normally, this type of cam can increase your power over the nose, without stealing pressure from the bottom-end. But in your case, at 5000 ft, if you're sharp, you have realized that this type of cam can be used to make the same power over the nose as the current cam does, but you can use it to increase your cylinder pressure and thus pick up power at low rpm.
Unfortunately, I don't think you will find an off-the-shelf, small-enough, solid lifter cam, to meet your needs. The theory is good, but I think that you will need a custom cam. by the time you get that done AND purchased/installed the adjustable gear, you could be close to the price of just installing hi-compression pistons, which is what your combo needs, and the which, will annihilate the weiner solid cam, with the 2bbl factory cam. At 5000 ft, pressure is or should be, your primary concern.
The Wallace calculator predicts your 2bbl cam (Ica of 56*) equipped 360 to currently make about 107psi@5000ft elevation. And the low-rpm power (below 3000/3500) is barely better than a factory stock 225 slanty at sealevel.
Performance starts at 130psi but doesn't really wake up until 140/145, and the best power will be achieved after 155psi. So as you can see, at 107 you cannot afford to give any pressure away.
If you had a 3400 stall or something, your pressure would be less of a concern, but 107psi is still pitiful.
Lets say the solid lifter cam has a 4 degree earlier closing intake, (now 52*); that will bring the pressure up to only 111psi.
But lets say you keep the 2-bbl cam and increase the compression ratio to 10.3. That would jump the pressure to 156psi@5000ft; A far greater power gain because it starts at idle/ zero mph.

As for me; I would not waste my time/money with camming this combo, with no other changes. So what! if you pick up 15 hp at 4600rpm; with your gears that doesn't show up until , ......... wait for it............. 48 mph. If the power march begins at 2hp@3400 rpm, that would be 34mph.

If anything, I would put a 3000TC on it and pick up say 40 ftlbs at 3000=23hp at ZERO mph; now that's what your combo needs. Ok well besides more compression,lol.
But to answer your question;
yes, it is possible to make more power over the nose without giving pressure/much pressure, away at the bottom-end.
But for less money spent, the TC will make you way happier.
Compare the cost of a solid-lifter cam and kit, plus adjustable valve gear, delivered and installed;
to the cost of a TC, delivered and installed.
Then compare guessing 12/15hp at 4600/48mph (one cam size bigger);
to guessing 23hp at zero-mph; (3000stall compared to 2200).
I know what I would do.
Click to expand...

I appreciate the input but I get the feeling you aren't too familiar messing with trucks (for towing and hauling, not "hot rod/muscle" trucks) as opposed to cars. First big point, you can't put a high-stall converter in a pickup truck that sees towing/hauling usage; you're just asking to overheat and frag your transmission and it will actually make pulling from a stop with a heavy load more difficult due to slippage. Kind of similar deal with increasing static compression ratio; with these old-style open-chamber heads, going much over 9:1 is asking for overheating and pinging issues when pulling heavy loads which would then require premium gas which I don't want to do when this truck averages 10 MPG. If I could build a 360/5.9 Mag with closed-chamber heads and decent quench that would be a different story but again, I'm not doing that lol there's no point.

Second, your entire argument is based on theory. I've found the hard way over the years (pinged a 10.5:1 360 to death due to too-small of a cam, yes I tried everything including timing/jetting adjustments, cold air intake, premium gas with octane booster) that the online cylinder pressure calculators are not very accurate; there's more to air density than just elevation above sea level. I'm going to run a cranking compression test today to confirm but I'm pretty sure last time I checked it was around 130 psi on this stock truck 360, not 107 like the Wallace calculator predicts. The way this thing moves when you step on the gas from a stop, there's no way it's making the same power as a 225 slant 6 at sea level and if I can just retain that same level of off-idle torque but with increased mid-range power and a wider RPM operating range I'll be very very happy.

Third, the point of increasing power with a *slightly* larger (same adv duration but more duration at .050" and more lift) cam isn't to give better acceleration from a stop over a set distance (1/4-mile, etc) like you would in a car with extra gear and converter. It's to give more mid-range power for merging and passing on the freeway and pulling heavy loads up steep hills at speed. Same reason I converted it to 4-bbl carb and added longtube headers; sure the acceleration from a stop is a bit better as I can wind it out to 4000 RPM holding it in 1st gear but the real benefit is when already moving at speed and needing to accelerate quickly to pass someone or pull onto a road with fast-moving traffic. Kickdown to 2nd and this thing moves.

Now with that said, I completely agree regarding gearing. Since this truck is a 3/4-ton it has a full-floating Dana 60 rear end and it would overall run much better with ~4.10 or ~3.91 gears but I'd need an overdrive transmission to drive on the freeway; speed limit on most parts of I-25 in Colorado is 75 mph with traffic often moving at 80-90 mph. Currently it turns about 3000 RPM at 80 mph which is already on the high side thinking in the context of fuel economy and heat load on the cooling system. I have considered swapping transmissions either to an A-518 or a 5 or 6-speed manual but I'm going to save that for the ultimate long-term plan: 5.9L Cummins diesel swap. Actually to be precise probably swap my cab and bed onto a later Cummins Dodge frame.

And you know what, most of this is a "what-if". The truck runs great as-is and I can't say for sure when I'd actually look at swapping the cam. But I wanted to get confirmation of the effects IF I decide to go that route, which is pretty likely.
 
And an added note about the cam's intended usage from the manufacturer: Very strong torque and increased HP for 273-360 c.i. motors. Compatible with stock type EFI. Works well for pleasure/ ski boats and mild towing applications. Advertised Duration (Int/Exh): 253/258 ;Duration @ .050 (Int/Exh): 208/213 ;Gross Valve Lift (Int/Exh): .454/.454 ;LSA/ICL: 112/108 ;Valve Lash (Int/Exh): Hyd/Hyd ;RPM Range: idle-5000

Somewhat ironically, the next-larger cam is actually advertised as being for heavy towing applications.
"Best mild performance cam. Works well in EFI applications with performance chip. Makes approximately 19" vacuum at idle. Great for performance marine and heavy towing applications. Great street rod cam. Slightly noticeable idle, works with stock converter, A/C, power brakes and stock springs in most cases.; Advertised Duration (Int/Exh): 256/262; Duration @ .050 (Int/Exh): 213/220; Gross Valve Lift (Int/Exh): .454/.475; LSA/ICL: 112/108; Valve Lash (Int/Exh): Hyd/Hyd; RPM Range: 1000-5500"

This larger 256/262 unit is the same cam I ran in a stock worn-out 318 and it was soggy on the low-end but put the same cam in that 10.5:1 360 I broke and the cylinder pressure was sky-high and pinged all the damn time.
 
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