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

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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.

That VooDoo works nice in a LOW compression (dished cast rebuilder pistons) 360, in my experience, but I did have the pinging you describe with a KB107 (10ish:1) pistoned 360 with the MoPar 260/268* .430/.450" cam. Took some tuning and still couldn't run peak advance (vacuum) when heavy towing.
 
Summit 6900 in 204 @.050 lift 421 ex 214 @.050 lift 444
summit 1789 in and ex 216 @.050 lift 454

Using a Erson cam that is identical to those specs in my 88 D250 with Eddy Performer inake, 600 Eddy carb, Headers. Electronic Ignition. Removed the old TBI and went with the carb and all, The truck runs great, it is an old Forest Service truck that had a 318. Now it runs great ,,,,pulls trailer with ease
 
Im currently running the luniti voodoo 702 my 360 its basically stock except the pistons and cam. The heads intake carb exhaust etc are all stock. I don't have alot of miles in it yet but so far it runs really well. Tons of power on the bottom end
 
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.
I guess I missed the towing/hauling part ......
on a sidenote;
I've never had a vehicle in over 50 years that was prone to "pinging". Almost every carburated car I have ever had was a Mopar tho; including my 1975 D100/318 ........... and almost every one of those was an SBM. I say almost every one, because there was this one exception, lol, a 1984Hyundai-Pony; but it burned anything, I mean absolutely anything, including several years old stale gas with a high percentage of diesel in it.
But you are right; I know nothing about towing/hauling, and had no idea that 33s were used for that with 3.55s.
Sorry I cluttered up your thread.
 
I guess I missed the towing/hauling part ......
on a sidenote;
I've never had a vehicle in over 50 years that was prone to "pinging". Almost every carburated car I have ever had was a Mopar tho; including my 1975 D100/318 ........... and almost every one of those was an SBM. I say almost every one, because there was this one exception, lol, a 1984Hyundai-Pony; but it burned anything, I mean absolutely anything, including several years old stale gas with a high percentage of diesel in it.
But you are right; I know nothing about towing/hauling, and had no idea that 33s were used for that with 3.55s.
Sorry I cluttered up your thread.

I'm sorry my tone was arrogant I shouldn't have worded my response that way, just the recommendation to run a higher-stall TC was a 'red flag' in my head, that's a big no-no with trucks so I ASSumed your knowledge was less than it is; also my fault for not mentioning the towing/hauling part initially. Like I said I agree regarding gearing, 3.54s (not 3.55, I just remembered since it's a Dana 60) and 33" tires isn't the setup for towing. You didn't clutter up my thread, you raised some valid points I just think the concerns about losing cylinder pressure and having my truck turn into a turd with anything but a stock cam are a bit over-exaggerated. I will look more seriously into re-gearing and perhaps swapping transmissions depending on how it performs.

@Bighead440 @70aarcuda what kind of weight were you towing? I intend to tow an open car-hauler trailer with my Duster on it so maybe 5000-6000 lbs. Really not that much for a 3/4-ton.
 
I'm sorry my tone was arrogant I shouldn't have worded my response that way, just the recommendation to run a higher-stall TC was a 'red flag' in my head, that's a big no-no with trucks so I ASSumed your knowledge was less than it is; also my fault for not mentioning the towing/hauling part initially. Like I said I agree regarding gearing, 3.54s (not 3.55, I just remembered since it's a Dana 60) and 33" tires isn't the setup for towing. You didn't clutter up my thread, you raised some valid points I just think the concerns about losing cylinder pressure and having my truck turn into a turd with anything but a stock cam are a bit over-exaggerated. I will look more seriously into re-gearing and perhaps swapping transmissions depending on how it performs.

@Bighead440 @70aarcuda what kind of weight were you towing? I intend to tow an open car-hauler trailer with my Duster on it so maybe 5000-6000 lbs. Really not that much for a 3/4-ton.

I had 31" tires and 3.55" gears with a 727, so it was spinning a few RPM at 65mph. I have towed a 16ft steel trailer with my 5000lb (NHRA scales) '76 GranFury wagon on it, but normally no more than a 4000lb car and trailer. I towed a 4000lb (car and parts) 1961 Plymouth Belvedere 2dr htp from past Windsor, Ontario Canada to central Georgia on I-75 back in 2004 with it, but it was mid December and very cold. Towing around Georgia in 100* heat wasn't ever really a problem though.
 
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.

We have similar vehicles
Smog era under powered heavy vehicles !!
My 886 is pretty heavy #7 Exh lobe was wipped out on this when I got it so after Isky cam and Dual port intake & lite weight fan installed its actually a capable vehicle now and wearing its original 4.10 gears it tows very well !!!

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