Camshaft recommendation for my specific Slanty build?

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hellfirechrome

hellfirechrome

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Howdy! Looking for an experienced recommendation for my build. First, the hardware;

1965 Plymouth Barracuda

Stock reman Slant six 225:
-Cliffy (not Offy!) Hyper-Pak
-Edelbrock 1403 with small jets & fat rods (live at 6200ft so leaned out)
-Stock exhaust manifold
-2.5" mandrel exhaust/glasspack muffler
-No PS or AC
-Electronic ignition (Mopar chrome box)

Driveline:
-904 Automatic Stock
-8 3/4" rear with 2.93/LSD
-4 wheel disc brakes, manual Wilwood style master

I'm looking for a midrange-RPM torque-centric cam, I have a vintage 13' camper trailer I'll be towing on occasion. Driving-wise, I prefer road course style driving power, not really drag/off the line. I plan on keeping the 2.93 for now, might go 3.55/3.73 down the line.

Whose cam & what grind(s?) should I lean toward for my build? What's going to give the most CFM flow improvement with that Hyper-Pak and still be streetable? I don't run Power brakes so a drop in vacuum/lopey idle is fine. I'm hoping someone will be speaking from experience running a Hyper Pak and similar 4bbl on a stock block. I've got NO interest in grinding heads, porting, polishing or anything too involved right now. Cams are an afternoon project, wanna keep it that way :)

Thanks in advance! Here's my baby, she's coming along nicely...

Cuda.jpeg
Slant.jpeg
 
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Actually your going the wrong way. Everything you are doing hurts torque. Wouldn't be so bad at a lower altitude. You really need to increase the compression ratio as the first mod. Almost any cam you install, will lower the effective (dynamic) compression ratio.
PS: That is NOT an Offie intake manifold. Looks like a Clifford.
PPS: Nice looking ride
 
Charrlie_S said:
Actually your going the wrong way. Everything you are doing hurts torque. Wouldn't be so bad at a lower altitude. You really need to increase the compression ratio as the first mod. Almost any cam you install, will lower the effective (dynamic) compression ratio.
PS: That is NOT an Offie intake manifold. Looks like a Clifford.
PPS: Nice looking ride
Click to expand...

Maybe I need a Torqstorm... ;)
 
I've never had a slant six nearly as fast as Charrlie_S's, but my 67 Barracuda used to have a slant six. Stock except for a four barrel carb, Offy intake, stock exhaust manifold with 2.25 inch pipe, automatic and 3.23 gears, it ran low 18's in the quarter. Milled the head a hundred thousandths and swapped in a 264/.440 Comp Cam (220 @ .050) - that dropped a full second off the quarter mile ET. Could have used more torque converter as my 60 foot time was only 2.50 (same as with the stock cam and CR), but I never bothered changing it or gears or anything else (until I swapped in a 360). Compared to the stock cam, the Comp Cam really woke it up from about 25 mph on up. It made for a nice daily driver, in town or on the interstate (could easily cruise at 80-85), with good passing power and a decent top end (110-115).
 
65 Cuda 340 said:
I've never had a slant six nearly as fast as Charrlie_S's, but my 67 Barracuda used to have a slant six. Stock except for a four barrel carb, Offy intake, stock exhaust manifold with 2.25 inch pipe, automatic and 3.23 gears, it ran low 18's in the quarter. Milled the head a hundred thousandths and swapped in a 264/.440 Comp Cam (220 @ .050) - that dropped a full second off the quarter mile ET. Could have used more torque converter as my 60 foot time was only 2.50 (same as with the stock cam and CR), but I never bothered changing it or gears or anything else (until I swapped in a 360). Compared to the stock cam, the Comp Cam really woke it up from about 25 mph on up. It made for a nice daily driver, in town or on the interstate (could easily cruise at 80-85), with good passing power and a decent top end (110-115).
Click to expand...

Yeah I'm new to living at elevation, looks like either a blower or shaving the heads is the only way I'm gonna get her to wake up. Looking forward to my trip to Sacramento in a few days, 50ft above sea level and SO many nice cruising spots... but I know I'll be able to feel the difference at sea level. Even my jeep V8 5.2 just wheezes up here LOL
 
hellfirechrome said:
Yeah I'm new to living at elevation, looks like either a blower or shaving the heads is the only way I'm gonna get her to wake up. Looking forward to my trip to Sacramento in a few days, 50ft above sea level and SO many nice cruising spots... but I know I'll be able to feel the difference at sea level. Even my jeep V8 5.2 just wheezes up here LOL
Click to expand...

Have you considered one of the throttle body EFI units available now? I just put one on my slant (Holley Sniper 4 bbl) and it made a huge difference. I had the Eddy 500 and a Holley 390 which were good but the closed loop control of the EFI just makes everything a lot easier, especially if you want to drive down the hill without changing out your fuel rods. There are 2bbl version as well from a few of the makers of these EFI units (Fitec, Edelbrock, MSD, etc.). The biggest improvement I noticed is Idle smoothness and part throttle power. Just a game changer for my car. They ain’t cheap, but probably the best bang for the buck.
I have an old MPP purple slant cam, similar to the Comp Cams that 65 Cuda 340 has and it really needs higher compression to work at lower rpms. You could shave off .080” and still run regular gas with that cam. Erson Cams has some really nice grinds too for the slant thou I don’t know if they still make them.
Best of luck on your project and keep us posted!
 
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Well, gentlemen, I've come to a good point! Since installing the Edelbrock and intake, finally finding a good tune (.83 jets, 6552-ish needles, I'd have to double check, and 8hg silver springs with the accelerator pump on the top hole), she was running pretty good but stumbly. Finally went back to address the timing, since I hadn't done her timing yet since the 4bbl install. Gave the dizzy a gentle twist to the left, and VIOLA! She picked up a smoother idle, I knew I hit the jackpot (I shoulda looked here first!). We took her for a spin and BAM! Power returned.

Just got back from a drive over hwy 88, Kit Carson pass at about 9,000ft elevation... she ran like a gem! Slightly rich up there, but plenty of power and hillclimbing in 2nd.

I think I'm pretty happy with the power output for now, but I'll look into thin head gaskets or a head shave soon. Still, that old saying applied in changed her road habits entirely; "timing is everything!"
 
hellfirechrome said:
... looks like either a blower ...
Click to expand...
Have you looked at the new Chinese electric superchargers? I've seen some youtubes. The cheap ones are worthless and even restrict airflow, but the $500+ ones actually work. I think that is the future, and certainly simpler and more elegant than the plumbing chore of a turbocharger or mounting a giant and expensive belt-driven supercharger. I understand there are current production cars with one (M-B). As one guy here promoted (Bill Dedman I recall), the slant six is a perfect candidate for boost. The small valves with manifolds on one side don't matter if you force the air in. Ditto for a high-lift camshaft.
 
Did you actually put a light on it? It's important you actually know where the initial and total timing is.
 
hellfirechrome said:
Well, gentlemen, I've come to a good point! Since installing the Edelbrock and intake, finally finding a good tune (.83 jets, 6552-ish needles, I'd have to double check, and 8hg silver springs with the accelerator pump on the top hole), she was running pretty good but stumbly. Finally went back to address the timing, since I hadn't done her timing yet since the 4bbl install. Gave the dizzy a gentle twist to the left, and VIOLA! She picked up a smoother idle, I knew I hit the jackpot (I shoulda looked here first!). We took her for a spin and BAM! Power returned.

Just got back from a drive over hwy 88, Kit Carson pass at about 9,000ft elevation... she ran like a gem! Slightly rich up there, but plenty of power and hillclimbing in 2nd.

I think I'm pretty happy with the power output for now, but I'll look into thin head gaskets or a head shave soon. Still, that old saying applied in changed her road habits entirely; "timing is everything!"
Click to expand...

Thats crazy my 500cfm eddy was lean out the box, actually had to jet up to .89 with with stock
rods secondaries where 1 stage leaner, i have the avs version. but my motors no stock probably how did you tune your carb with an Air fuel ratio sensor?
 
Yeah for a stock motor there's no way she was going to use all of that gas, I went through multiple jets and needles to get it idling smooth and using all the fuel under acceleration, not to mention timing. It was all centered around that damn bog. Now that I have the timing where it needs to be, I'm gonna play with needles and accelerator pump again to dial it in. I'm old school, I tune by driving and exhaust rich/lean smell. Learned from the best as a teen working on dad's Studebakers. I'll get an AFR soon, but she's driving so well (even at altitude!) that I don't care about an extra 10hp here or there. Just happy with smooth power (feels like a 273!) and cold running. I run a 160 thermostat, step up to a 180 in winter. Will also put an electric heat pad under the hyper-pak intake/carb plenum for the winter.
 
hellfirechrome said:
Yeah for a stock motor there's no way she was going to use all of that gas, I went through multiple jets and needles to get it idling smooth and using all the fuel under acceleration, not to mention timing. It was all centered around that damn bog. Now that I have the timing where it needs to be, I'm gonna play with needles and accelerator pump again to dial it in. I'm old school, I tune by driving and exhaust rich/lean smell. Learned from the best as a teen working on dad's Studebakers. I'll get an AFR soon, but she's driving so well (even at altitude!) that I don't care about an extra 10hp here or there. Just happy with smooth power (feels like a 273!) and cold running. I run a 160 thermostat, step up to a 180 in winter. Will also put an electric heat pad under the hyper-pak intake/carb plenum for the winter.
Click to expand...
Still waiting for that fuel pump to turn up and I see you are still out here acting like a good trusted member......
 
BARNEY'S CAR said:
Still waiting for that fuel pump to turn up and I see you are still out here acting like a good trusted member......
Click to expand...

****, it's been forever man! I reshipped the box by UPS, had to repack after they stopped the package for a little fuel leak. I had no idea you never got it? I was basically homeless for almost a year, a lot of stuff slipped by. I'll see if I can fond any old UPS shipping info.
 
green72 said:
Well that got awkward.
Click to expand...
It should get awkward. He was selling a Distributor ,in tank fuel pump and Fitech system. Asked x amount ,talked on phone requested F/F seemed ok as I usually did not dot that, sent the money and NEVER saw the pump and he ignored me after that. My fault I guess for trusting him but really my worst encounter here in 10+ years. I have a warning in the appropriate section here but who knows if people read them...although it looks like some do not.
 
BARNEY'S CAR said:
It should get awkward. He was selling a Distributor ,in tank fuel pump and Fitech system. Asked x amount ,talked on phone requested F/F seemed ok as I usually did not dot that, sent the money and NEVER saw the pump and he ignored me after that. My fault I guess for trusting him but really my worst encounter here in 10+ years. I have a warning in the appropriate section here but who knows if people read them...although it looks like some do not.
Click to expand...

Well I haven't heard from you in ages and thought you must have got it. It's been... what, over two years? I can't seem to find anything in my old box of receipts and UPS says it's way too out of date to figure out. Should I mail you a fuel pump? Still want the in-tank? Or is inline better?
 
hellfirechrome said:
Howdy! Looking for an experienced recommendation for my build. First, the hardware;

1965 Plymouth Barracuda

Stock reman Slant six 225:
-Cliffy (not Offy!) Hyper-Pak
-Edelbrock 1403 with small jets & fat rods (live at 6200ft so leaned out)
-Stock exhaust manifold
-2.5" mandrel exhaust/glasspack muffler
-No PS or AC
-Electronic ignition (Mopar chrome box)

Driveline:
-904 Automatic Stock
-8 3/4" rear with 2.93/LSD
-4 wheel disc brakes, manual Wilwood style master

I'm looking for a midrange-RPM torque-centric cam, I have a vintage 13' camper trailer I'll be towing on occasion. Driving-wise, I prefer road course style driving power, not really drag/off the line. I plan on keeping the 2.93 for now, might go 3.55/3.73 down the line.

Whose cam & what grind(s?) should I lean toward for my build? What's going to give the most CFM flow improvement with that Hyper-Pak and still be streetable? I don't run Power brakes so a drop in vacuum/lopey idle is fine. I'm hoping someone will be speaking from experience running a Hyper Pak and similar 4bbl on a stock block. I've got NO interest in grinding heads, porting, polishing or anything too involved right now. Cams are an afternoon project, wanna keep it that way :)

Thanks in advance! Here's my baby, she's coming along nicely...

View attachment 1715589032 View attachment 1715589033
Click to expand...

Spent months with Doug Dutra with a simulator and selecting parts for my 225 looking for the exact same thing. I just got mine running last weekend and have not dialed it in for real yet but wow does it run great for a fun grocery getter. It will die off over 4000 RPM but I never drive it there.

Here is what I did.

225 Torque Build is Alive....

for what you want the hyper pack long runners are for a 170 running 7000 RPM on the track. Not useful in a 225 with high gears. For 4000 RPM max builds the key ingredients are

1) up the compression by milling the block.
2) Dutra Duals with the Y connecting them 45” to 50” from the flange any closer and it only helps above 4000 RPM
3) a cam with no more 108 LCA. And short duration. Yes you heard me right. The 268 comp cams are too much duration and you loose a lot under 4000 RPM (but you do gain a lot over) use a Oregon Cam 2106 or a Dutra RV10. Don’t get in the RVP discussion. It really does not matter for under 4000 RPM builds. You just want short duration for street torque. The Dutra RV15 is between these and the Comp cam.
4) don’t go too big on the CFM of the carbs. For 4000 RPM and less engines 400 is all you need and if you can do it in a way that can be progressive so you have less than that at lower RPM the better. You take my build and throw 500 CFM carb on it and it tanks the low end torque for gains at high RPM (if you have the oversized valves to use the more flow)

I did oversized valves as that does help keep the power up at higher RPM with the short duration. Would I do it again? Maybe. I need to get some peddle time on this build to answer that.

Jim.
 
hellfirechrome said:
Well I haven't heard from you in ages and thought you must have got it. It's been... what, over two years? I can't seem to find anything in my old box of receipts and UPS says it's way too out of date to figure out. Should I mail you a fuel pump? Still want the in-tank? Or is inline better?
Click to expand...
The fuel pump was a Fitech 40102 I would take one of those since I have paid you for it
 
BARNEY'S CAR said:
The fuel pump was a Fitech 40102 I would take one of those since I have paid you for it
Click to expand...

Cool. I'll cobble some $ together and send one along. Not working due to COVID shutdowns but I have some parts to sell. PM me your mailing address.
 
BillGrissom said:
Have you looked at the new Chinese electric superchargers? I've seen some youtubes. The cheap ones are worthless and even restrict airflow, but the $500+ ones actually work. I think that is the future, and certainly simpler and more elegant than the plumbing chore of a turbocharger or mounting a giant and expensive belt-driven supercharger. I understand there are current production cars with one (M-B). As one guy here promoted (Bill Dedman I recall), the slant six is a perfect candidate for boost. The small valves with manifolds on one side don't matter if you force the air in. Ditto for a high-lift camshaft.
Click to expand...
@BillGrissom
Which supercharger are you talking about? The only ones I’ve been able to find that look like they might actually work cost more than a TorqStorm and need 48 volts to run.
 
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