The intellectual post,about old school camshafts,the newer ramp cams.. and what's needed ,in modifi

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Abodybomber

Abodybomber

Breaking street machines , since 1983.....:)
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Doesn't matter what engine:....: I ran a Crower solid flat flat tappet,with the "hardened lobes, against basic stock solid lifters... the spring pressures were 130 ,on the seat...340 on the nose... Was using ,the old school Kendall zinc green oil.was never informed 9f ConocoPhillips,buying them out... It died ,cam is fine,lifters damn dead.... I like the older cam profiles ,if you know how to manage it... This is a combination of real history posted by you,and theory by you... I actually like slower camshaft profiles, at the moment. Share your concepts, comments,and negatively ....
 
My theory is to let someone who knows more about it than I do theorize on the subject.:D
I know about enough on cams to get myself in trouble.
So you are saying the oil did you in or the hardened lobes, or the pressures?
 
What I've been finding over and over again is that there is "Nothing new under the sun" The old grinds make excellent power AND last. The latest flavour of the week fast rate grind may make slightly more power but you can bet it won't last unless you have a very sciencend out valvetrain. The old tried and true lobes actually produce a much nicer power curve as well IME. J.Rob
 
RAMM said:
What I've been finding over and over again is that there is "Nothing new under the sun" The old grinds make excellent power AND last. The latest flavour of the week fast rate grind may make slightly more power but you can bet it won't last unless you have a very sciencend out valvetrain. The old tried and true lobes actually produce a much nicer power curve as well IME. J.Rob
Click to expand...

That is a question I asked awhile back.
"How many ways to grind a lobe could there possibly be?"
Except maybe for roller ramps and stuff like that maybe, it seems it all has to have been done before.
 
Abodybomber said:
Doesn't matter what engine:....: I ran a Crower solid rat flat tappet,with the "hardened lobes, against basic stock solid lifters... the spring pressures were 130 ,on the seat...340 on the nose... Was using ,the old school Kendall zinc green oil.was never informed 9f ConocoPhillips,buying them out... It died ,cam is fine,lifters damn dead.... I like the older cam profiles ,if you know how to manage it... This is a combination of real history posted by you,and theory by you... I actually like slower camshaft profiles, at the moment. Share your concepts, comments,and negatively ....
Click to expand...
So you went high tech and it didn't work out, all the lifter bits went the through the bearings and you're kinda pissed about it...though in the back of your mind you wondered if it would work and or how long it would last.....right?

The learning curve, isn't always free, but it is totally worth it when not too far out there in left field. The Kendall gt, haven't seen it around for 8 or 10 yrs. 340 open is edgy or a bit much, depending on the lobe in some cases. You would be better off with finding a lil spring and bounce than lobe destruction...both suck.
The newer lobe gives you a few more tq outside the power band, just keep the open around 310-315 on the average .520-.570 lift fast rate or youll start gradually wiping the top of the lobe off.
You must remember...Rpms and open pressure dance close together, don't raise one over the other or you'll pay the price.
You won't be the first or the last...and no one is 100% immune to this.
Next time try a composite lifter...lol ...or solid roller ;)
 
I thought about going roller on my Barracuda engine a few yeara ago but I just couldnt bring myself to spend the wxtra bucks.

2 cams and a shitload of my free time later
I have a magnum 5.9 roller motor in the works....
And the 408 W2 motor for the Swinger gets a solid roller from the start.
 
MPOffical; They (who?) still make a composite lifter?

ABBomber; Cam broken in with outer springs only? Old (sealed) oil? Lifter incompatibility?

As far as slow rate/ramp cams go, there not the end of the world. Fine for general useage. Many will state if the stock cost $200 for ether, why wouldn't you....

Engine build/target dependent, the cam chosen will suite, engine build or drivers peace of mind or both.
 
For what I'm doing, high 11s good air, low 12s crap air 1/4 mile a .500 lift solid FT (Comp Cam XS274S) with Howards EDM lifter works fine. The MP magnum roller cam single spring/damper installed at 1.70 spring height with OEM LA retainer on J heads handles the 6K shift no problem. I also run tighter lash .012/.014 cold vs .016/.018 hot that cam card recommends. I use Valvoline VR1 30W high zinc for break in and then switch to AMS Oil 30W.
 
It depends on the situation.

But for a street friendly engine I think it better to build power with cylinder heads over cam.

There's a guy on here dyno his 340 and made 400 hp with stock 340 cam but used edlebrock heads.

To make 400hp with stock x heads you need to run around xe285h cam. Which would obviously be less streetable and harder on valvetrain. The stock cam is about par with comps xe250h so that's quite a few step ups in the cam department.
 
273 said:
It depends on the situation.

But for a street friendly engine I think it better to build power with cylinder heads over cam.

There's a guy on here dyno his 340 and made 400 hp with stock 340 cam but used edlebrock heads.

To make 400hp with stock x heads you need to run around xe285h cam. Which would obviously be less streetable and harder on valvetrain. The stock cam is about par with comps xe250h so that's quite a few step ups in the cam department.
Click to expand...


Very true. It's always better to use the head/intake to make power than the cam.
 
yellow rose said:
Very true. It's always better to use the head/intake to make power than the cam.
Click to expand...

The cam is there to take advantage of the heads to maximize,realize and expliot their power potential.

Same everything else, engine with the better grind wins. It's all relative.
I like the old MP cams, all solids .490, .528, .557 , .590...all great.
Then the grinder changed or the stock and they started going to ****, like MP, comp, some crane as well, plus crane liked to call for a little higher than others pressure. Hughes is what got me, never seen a cam go flat so fast.
Never even drove it, in fact a leaking intake gasket lead me to it where no.7 was just starting to flat near full lift.

Point of this thread from reading into the opening post is 'gamble if you can afford it, always appreciate the lesson, but know the rules and bend them at your own risk.'

Fast rate flat cams better have the right spring pressures and use the right oil.
All conventional grinds can play around some with pressures, though higher you go so better the rpm and then the oil quality is my thinking...in other words run as little spring as you can get away with=the recommended, then realize that the higher pressures mean higher rpms, as in you can't let them idle low like a street car and they aren't endurance pieces in the first place.lol

Aint learning fun...
 
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MOPAROFFICIAL said:
The cam is there to take advantage of the heads to maximize,realize and expliot their power potential.

Same everything else, engine with the better grind wins. It's all relative.
I like the old MP cams, all solids .490, .528, .557 , .590...all great.
Then the grinder changed or the stock and they started going to ****, like MP, comp, some crane as well, plus crane liked to call for a little higher than others pressure. Hughes is what got me, never seen a cam go flat so fast.
Never even drove it, in fact a leaking intake gasket lead me to it where no.7 was just starting to flat near full lift.

Point of this thread from reading into the opening post is 'gamble if you can afford it, always appreciate the lesson, but know the rules and bend them at your own risk.'

Fast rate flat cams better have the right spring pressures and use the right oil.
All conventional grinds can play around some with pressures, though higher you go so better the rpm and then the oil quality is my thinking...in other words run as little spring as you can get away with=the recommended, then realize that the higher pressures mean higher rpms, as in you can't let them idle low like a street car and they aren't endurance pieces in the first place.lol

Aint learning fun...
Click to expand...
MOPAROFFICIAL said:
The cam is there to take advantage of the heads to maximize,realize and expliot their power potential.

Same everything else, engine with the better grind wins. It's all relative.
I like the old MP cams, all solids .490, .528, .557 , .590...all great.
Then the grinder changed or the stock and they started going to ****, like MP, comp, some crane as well, plus crane liked to call for a little higher than others pressure. Hughes is what got me, never seen a cam go flat so fast.
Never even drove it, in fact a leaking intake gasket lead me to it where no.7 was just starting to flat near full lift.

Point of this thread from reading into the opening post is 'gamble if you can afford it, always appreciate the lesson, but know the rules and bend them at your own risk.'

Fast rate flat cams better have the right spring pressures and use the right oil.
All conventional grinds can play around some with pressures, though higher you go so better the rpm and then the oil quality is my thinking...in other words run as little spring as you can get away with=the recommended, then realize that the higher pressures mean higher rpms, as in you can't let them idle low like a street car and they aren't endurance pieces in the first place.lol

Aint learning fun...
Click to expand...
NAILED IT!!!!! Nice interpretation ,of my mild rant....
 
MOPAROFFICIAL said:
The cam is there to take advantage of the heads to maximize,realize and expliot their power potential.
Click to expand...

I totally agree.
I look at it this way, like a piece of marble you chip away at to reveal the statue.
Same with hp the head it raw material and everything else is to reveal it's potential.

The rule of thumb is 2 hp per cfm but most engines fall short and to reveal that amount you'd need a serious amount of cam and cr.

Most hot or street strip engine is gonna run around a 285 ish cam with 10:1-11:1 cr. Which usually makes around 1.8-1.9 hp per cfm.

For a more street friendly engine your gonna want to be more 1.6-1.7 hp per cfm and around 1 hp per cid.

I agree that when pushing cam choice you should do everything you can afford to run less spring pressure. Even for a street engine beehives with a light retainer will allow less spring and give more engine life.
 
How many decades were there where all we had was considered "slow and lazy" ramps by today's standards? How many records were broken in how many classes by those slow and lazy ramps? How many of those back in the day racers would still be faster and quicker than what anyone here has today?

That's all I got.
 
Allways but allways get the best/most cylinder head you afford dollar wise and for the engine at hand.

Build power with a cam. I never thought that way. Cam is 2 things to me. On the simple.

Duration = RPM band
Lift = How much air it is allowing the engine to breath in. Hence, that wonderful word again, HEADS! And everything above it and attached to it.
Breath in, breath out peoples.

For the beginner or new guy.
On a streeter/budget racer level, that's all you need to know.
There really is no reason to over think it.
 
mderoy340 said:
For what I'm doing, high 11s good air, low 12s crap air 1/4 mile a .500 lift solid FT (Comp Cam XS274S) with Howards EDM lifter works fine. The MP magnum roller cam single spring/damper installed at 1.70 spring height with OEM LA retainer on J heads handles the 6K shift no problem. I also run tighter lash .012/.014 cold vs .016/.018 hot that cam card recommends. I use Valvoline VR1 30W high zinc for break in and then switch to AMS Oil 30W.
Click to expand...
I do the same thing as far as valve settings (cold), but go about .006/.007 tighter than recommendations, because of my alum. heads. If u have iron heads-not so much.
 
I like the idea of an old school grind , lifters with the lube hole in the lifter base, combined with a slightly higher rocker ratio and beehive springs that would match the recomended spring recomendations. If you want, add in some lighter valves or retainers. Most important is MAKE SURE THE LIFTERS ROTATE BEFORE YOU FIRE IT.
The idea is to not exceed the loads on the cam and lifters as originally designed, just put to use the new things available to us. This is my idea of day in day out reliability in a performance engine. Just don't try and force an engine to have a wider torque band with fast rate lobes, unless you know what you are getting into.
Best of all, just start with a roller motor like a magnum, and sleep very well.
 
True. A Hyd. roller has the best, widest street friendly workings.
 
I should have stopped reading at intellectual!!

images-1.jpeg
 
Abodybomber said:
Doesn't matter what engine:....: I ran a Crower solid flat flat tappet,with the "hardened lobes, against basic stock solid lifters... the spring pressures were 130 ,on the seat...340 on the nose... Was using ,the old school Kendall zinc green oil.was never informed 9f ConocoPhillips,buying them out... It died ,cam is fine,lifters damn dead.... I like the older cam profiles ,if you know how to manage it... This is a combination of real history posted by you,and theory by you... I actually like slower camshaft profiles, at the moment. Share your concepts, comments,and negatively ....
Click to expand...

How fast can you go with a white box 204/214 cam on 112* lsa .420/.454 lift with 1.5 rockers?
 
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