440 cam selection question

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1967BarracudaGeorge

1967BarracudaGeorge

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So far this is the one area that I'm having difficulty with.

I will describe the parameters of my build and hopefully someone can help me find the closest cam that will work.

440 block, stock rods, forged crank and forged TRW flattop pistons.
Ported 915 heads, stainless valves, 1.81 exhaust, 2.14 intake, springs rated for .500 lift, stock 1.5 rocker arms.
Offenhauser 2×4 intake, matching AFB primary and secondary carbs.
Mancini tri y headers
3:55 gear, 14" tires

It will be a street car, rare if any track time.

I'd like around .286 duration and .485 lift at .50 if possible. I want to have as much power as possible, without having to worry about smashing a piston into a valve.

I want to run hydraulic flat tappet, American made, absolutely no Compcams, or low-end cams..

Thanks
 
I have a Summit 4601 I believe is the number. I believe Crane was the maker. Good all around power smooth idle
 
Ported heads but springs for only .500 lift? The heads could handle that life totally unported. What was the point of the porting if not to take advantage of it? I'm baffled by that. But a decent cam for that combination with those springs limiting the heck out of it would be Comp's version of the Road Runner cam. It at least has Mopar specific lobes for the .903 lifter. I sure wouldn't run some generic cam with Chevy style lobes when you're already cutting your own throat with those valve springs.

I see you said "no Comp" but you can easily get Schneider or another cam grinder to grind one with Mopar lobes. Any of them can do it.
 
RustyRatRod said:
Ported heads but springs for only .500 lift? The heads could handle that life totally unported. What was the point of the porting if not to take advantage of it? I'm baffled by that. But a decent cam for that combination with those springs limiting the heck out of it would be Comp's version of the Road Runner cam. It at least has Mopar specific lobes for the .903 lifter. I sure wouldn't run some generic cam with Chevy style lobes when you're already cutting your own throat with those valve springs.

I see you said "no Comp" but you can easily get Schneider or another cam grinder to grind one with Mopar lobes. Any of them can do it.
Click to expand...
I don't have valve springs yet. The reason why I'm looking at .500 lift capability is because I wasn't looking for a cam with more than that much lift.
The ported heads are some that my cousin used on his old 440. I'm a novice, so alot of this is not set in stone.
 
1967BarracudaGeorge said:
I don't have valve springs yet. The reason why I'm looking at .500 lift capability is because I wasn't looking for a cam with more than that much lift.
The ported heads are some that my cousin used on his old 440. I'm a novice, so alot of this is not set in stone.
Click to expand...
I understand now. But in limiting yourself to .500 lift, you completely REMOVE any advantage your porting gives you....in other words, you're effectively wasting whatever money you spent on porting. If that makes sense. Porting the heads was the superhighway to choosing a cam with greater lift than .500, since the stock heads can handle that much flow at that lift. Is this an engine you plan to run headers on? Forgive me if you said and I overlooked it. If you plan on headers, then that even negates further your port work if you stick with a cam under .500 lift. At least, that one old dumbass's opinion. I would be looking into cams with .550-.575 lift.....that is of course using the flow sheets as a guide. Is a solid lifter cam out of the question?
 
1967BarracudaGeorge said:
I don't have valve springs yet. The reason why I'm looking at .500 lift capability is because I wasn't looking for a cam with more than that much lift.
The ported heads are some that my cousin used on his old 440. I'm a novice, so alot of this is not set in stone.
Click to expand...
I see......does your cousin happen to have flow information on the heads?
 
RustyRatRod said:
I understand now. But in limiting yourself to .500 lift, you completely REMOVE any advantage your porting gives you....in other words, you're effectively wasting whatever money you spent on porting. If that makes sense. Porting the heads was the superhighway to choosing a cam with greater lift than .500, since the stock heads can handle that much flow at that lift. Is this an engine you plan to run headers on? Forgive me if you said and I overlooked it. If you plan on headers, then that even negates further your port work if you stick with a cam under .500 lift. At least, that one old dumbass's opinion. I would be looking into cams with .550-.575 lift.....that is of course using the flow sheets as a guide. Is a solid lifter cam out of the question?
Click to expand...
My reason for wanting to stay below .500 lift was so I would be safe with flattop pistons. I have 2 sets of TRW forged flattop pistons and didn't want to spend $600+ to get some with valve reliefs.

The porting that had been done was to gasket match the intake and exhaust.
 
Have a look at the Mopar purple shafts on the Mancini website.
Mopar Performance ''Purple Shaft'' Camshaft Kit

I agree with everything RustyRatRod already said. With that 2X4 intake manifold and heads combination indicates this is clearly a throwback street showcar. More show than go as compared to current engine technology standards. No disrespect intended. A fun car that will attract a lot of attention from onlookers, but won't be an incentive for the driver to be foolish and to attract the attention of the local police. A fun car with 350 honest hp which is plently to keep anyone entertained on an evening cruise with the spouse and kids.

The most important thing to keep any flat tappet camshaft alive with be doing a proper break in procedure. After that you can reasonably expect it to last as long as you have the car.

FYI, the pistons you have are almost certainly clearanced for valve lifts of .550 at least. So you could go a little bit bigger on the cam, if you put in different valve springs. Though that would just hurt the driveability of the car, with only a relatively small gain in HP at the RPM redline.

Lastly, I'll comment on the stock connecting rods. They were built strong enough to easily rev to 6,500 rpm and live. But they are also at least 50 years old, and undoubtedly have many millions of cycles on them. There is no way to know how fatigued they are and how much abuse they will take today. So it is better for the engine to use a small cam, with a big torque curve down low and keep the RPM under 5,500. Do that and it will be great fun and last forever.

Post some pics, everyone would love to see the project as it progresses.
 
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MinnesotaMopar said:
Have a look at the Mopar purple shafts on the Mancini website.
Mopar Performance ''Purple Shaft'' Camshaft Kit

I agree with everything RustyRatRod already said. With that 2X4 intake manifold and heads combination indicates this is clearly a throwback street showcar. More show than go as compared to current engine technology standards. No disrespect intended. A fun car that will attract a lot of attention from onlookers, but won't be an incentive for the driver to be foolish and to attract the attention of the local police. A fun car with 350 honest hp which is plently to keep anyone entertained on an evening cruise with the spouse and kids.

The most important thing to keep any flat tappet camshaft alive with be doing a proper break in procedure. After that you can reasonably expect it to last as long as you have the car.

FYI, the pistons you have are almost certainly clearanced for valve lifts of .550 at least. So you could go a little bit bigger on the cam, if you put in different valve springs. Though that would just hurt the driveability of the car, with only a relatively small gain in HP at the RPM redline.

Lastly, I'll comment on the stock connecting rods. They were built strong enough to easily rev to 6,500 rpm and live. But they are also at least 50 years old, and undoubtedly have many millions of cycles on them. There is no way to know how fatigued they are and how much abuse they will take today. So it is better for the engine to use a small cam, with a big torque curve down low and keep the RPM under 5,500. Do that and it will be great fun and last forever.

Post some pics, everyone would love to see the project as it progresses.
Click to expand...
I like the specs on the purple shaft cam.
I'll magnaflux the rods and get my machinist to resize them.
I can get my cousin to fine tune the carburetors for maximum performance.
I'll even have valve reliefs cut into the pistons if necessary.
I'm planning on a mild 500hp build. My cousin had that much in the early 70s in his '68 Coronet. I'm building virtually the same engine in a car that's 1,000 lbs lighter.
Also, I'll be using a 4 speed with A/C. It's a must have in Texas.
 
1967BarracudaGeorge said:
My reason for wanting to stay below .500 lift was so I would be safe with flattop pistons. I have 2 sets of TRW forged flattop pistons and didn't want to spend $600+ to get some with valve reliefs.

The porting that had been done was to gasket match the intake and exhaust.
Click to expand...
I get it. But the duration is much more important to watch than lift. It's not the how much that gets you in trouble, it's the when the valve opens and how long it stays open. It's a big block. It's gonna make power either way.
 
RustyRatRod said:
I think so, yeah. But you'll want to make SURE to check spring retainer to guide clearance at full lift. Some have tons of room, while others can make contact before .500 lift, so be careful. It's a very simple procedure to shorten the guide, especially since the heads are not assembled yet. Just keep an eye on it.
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Thanks, I appreciate it!
 
[1] The max valve lift has nothing to do with valves contacting pistons. Duration & overlap is what affects P to V clearance.
[2] There is nothing wrong with Comp Cams cams per se. They sell more cams than anybody else, so more failures. The problem is todays junk flat tappet lifters; there are only 1-3 companies making them & they supply ALL the cam companies. If you do not want a cam failure, get some NOS 25+ yr old lifters......or have an old stock set of lifters re-faced.
[3] You have a good parts combo for what you want to do. Could it be better? Maybe, but you already have everything.
[4] Look at using beehive v/springs. These require less spring tension to control the valve train & your cam/lifters/valve train will last longer.
[5] I would use the Isky 280 Mega Hyd cam with Comp #26986 b/hive springs
 
Bewy said:
[1] The max valve lift has nothing to do with valves contacting pistons. Duration & overlap is what affects P to V clearance.
[2] There is nothing wrong with Comp Cams cams per se. They sell more cams than anybody else, so more failures. The problem is todays junk flat tappet lifters; there are only 1-3 companies making them & they supply ALL the cam companies. If you do not want a cam failure, get some NOS 25+ yr old lifters......or have an old stock set of lifters re-faced.
[3] You have a good parts combo for what you want to do. Could it be better? Maybe, but you already have everything.
[4] Look at using beehive v/springs. These require less spring tension to control the valve train & your cam/lifters/valve train will last longer.
[5] I would use the Isky 280 Mega Hyd cam with Comp #26986 b/hive springs
Click to expand...
I'm looking at some Mopar performance valve springs with an inner spiral "thing" (lol). I forgot what they called it.
I wish I could find some 25 year old lifters.
I still have to buy a few things, like headers in particular.
I'm feeling pretty good about the purple cam. Plus being a cam/lifter combo is a big factor.
One of my 440 blocks has the old lifters stuck in.it, but I seriously doubt that they would be serviceable.
 
1967BarracudaGeorge said:
I'm looking at some Mopar performance valve springs with an inner spiral "thing" (lol). I forgot what they called it.
I wish I could find some 25 year old lifters.
I still have to buy a few things, like headers in particular.
I'm feeling pretty good about the purple cam. Plus being a cam/lifter combo is a big factor.
One of my 440 blocks has the old lifters stuck in.it, but I seriously doubt that they would be serviceable.
Click to expand...
Those are called dampers. It's sill a single spring, though. Here's a tip for decent lifters, even if they are new ones. As long as you get lifters with a heavy duty snap ring holding the plungers in, instead of the puny wire retainers, you've probably found a good lifter.
 
1967BarracudaGeorge said:
My reason for wanting to stay below .500 lift was so I would be safe with flattop pistons. I have 2 sets of TRW forged flattop pistons and didn't want to spend $600+ to get some with valve reliefs.

The porting that had been done was to gasket match the intake and exhaust.
Click to expand...
Are your pistons at .0000 deck ?
Have your heads been milled ?
If I remember correctly at .500 the valve hasn't even left the chamber off the seat.
Also flat top trw pistons are usually.090 in the hole.
This combo if the decks are stock is probably around 9.4:1 compression fyi.
No offense Your combo sounds more like mid 400 horse, I've seen many 500 HP 440s and they have a bit more than what you have planned out but you can do it, just need that cam to be right, CALL HUGHES ON MONDAY
 
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In my opinion, just look at Hughes engines for a cam, they'll tell you exactly what you need for any cam they have.
 
RustyRatRod said:
Those are called dampers. It's sill a single spring, though. Here's a tip for decent lifters, even if they are new ones. As long as you get lifters with a heavy duty snap ring holding the plungers in, instead of the puny wire retainers, you've probably found a good lifter.
Click to expand...
Thanks, I'll keep that in mind when looking at lifters.
 
MOPARMAGA said:
Are your pistons at .0000 deck ?
Have your heads been milled ?
If I remember correctly at .500 the valve hasn't even left the chamber off the seat.
Also flat top trw pistons are usually.090 in the hole.
This combo if the decks are stock is probably around 9.4:1 compression fyi
Click to expand...
The heads have been milled. I will have to use a medium thickness head gasket to get the compression down.
I don't have anything assembled, so I don't know any of the measurements as far as deck height.
 
1967BarracudaGeorge said:
The heads have been milled. I will have to use a medium thickness head gasket to get the compression down.
I don't have anything assembled, so I don't know any of the measurements as far as deck height.
Click to expand...
Better clean up some stuff and mock it up, guessing on parts gets expensive....just ask ME LOL
 
valve clearance is important during the overlap period when the piston is near top dead center.
Allways remember the piston is running away from the intake and chasing the exhaust.
 
MOPARMAGA said:
Better clean up some stuff and mock it up, guessing on parts
Click to expand...

MOPARMAGA said:
Are your pistons at .0000 deck ?
Have your heads been milled ?
If I remember correctly at .500 the valve hasn't even left the chamber off the seat.
Also flat top trw pistons are usually.090 in the hole.
This combo if the decks are stock is probably around 9.4:1 compression fyi.
No offense Your combo sounds more like mid 400 horse, I've seen many 500 HP 440s and they have a bit more than what you have planned out but you can do it, just need that cam to be right, CALL HUGHES ON MONDAY
Click to expand...
I'll call them next week and in the meantime I'll look at their website.
I want as much power as possible and still be able to use my pistons.

Thanks
 
1967BarracudaGeorge said:
I'll call them next week and in the meantime I'll look at their website.
I want as much power as possible and still be able to use my pistons.

Thanks
Click to expand...
Most of the time you will find you have a mile of clearance. Mopar's are known for that, chevy not so much.
Hughes will get you going for sure, they know camshafts.
 
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