[bullheimer]

so everybody loves this 068 except a couple of you, and it comes in at 116 lsa, the 744 is at 119, and the 041 is a 114. i am thinking mostly of the 068 because it is recommended a LOT but my question is this, didn't the large lsa's counteract the high c.r.'s those engines had? bleeding some of it off? and if that is the case, wouldn't i be better off, if i had to have an 068, and i have a c.r. of only 9:1, to get the same grind, but with an lsa of only 112 or even 110? just curious. read the 10+page post on ultradynes in a 455, i have a 400 so i still don't know the answer. just like i read cam posts for like a year and still bought the wrong one. i am going to get an 068, mainly cause of the lower lift for my pressed in studs, but if i do that, i just want to know if my 9:1 cr would be too low for a 116 lsa. thx.

[Blued and Painted]

wider lsa's can make long advertised duration cams easer to live with like the 068
-- http://www.pontiacpower.org/PontiacCams.htm --

wider lsa cams tend to have a broad power range but triad off some peak HP.

[Will]

bullheimer - It's not the LSA so much as it is the intake closing point that determines dynamic compression. Of course, cams with wider LSAs typically have later intake closing points, all else being equal.

So your intuition that a cam with a little narrower LSA might work better in a lower compression motor has merit. Personally, I'd run something like a Crower 60918 or Summit 2801 in a 9:1 400 over the 068 if you want a mild cam with a lot of low end grunt.

IMO, the 068 has it's place but there are plenty of other good cams out there and in general I tend towards wanting to see more modern lobe profiles with more lift and a little narrower LSA.

The 068 was designed to be the HO cam when HO motors had 10.5:1 CRs and leaded premium was readily available. It still saw use in 455s in the early '70s because a 455 can soak up a lot of duration and still be very mild and the 068 really doesn't have a lot of .050" duration anyway.

In other words, I'd tend to stick with using the 068 the way the factory did - for higher compression motors or big low compression motors.

[Cliff R]

The long duration factory cams and many early high performance cams, like the Blue Racer, Melling and Speed Pro grinds, are also very easy on the valve train. They have gently opening and closing events, which doesn't require as much spring pressure to keep things in check, nor does it tend to create harmonics at high rpms that can lead to power loss.

It may also help reduce lobe failure, or not contribute to it, but that's just a guess on my part.

Some engine builders call the high rpm thing "lifter crash". I've witnessed this myself right on the dyno with several flat cams (all of them were Comp XE grinds), and have also observed fast ramp HR cams go "dead" as well, just like you cut out the voltage to the distributor.

The first HR cam I used in my last 455 would rip your head off to exactly 5800rpm's, and would not rev one rpm past that point.

I topped the current HR cam with Crower HIPPO solid roller lifters and it will rev right past 6000rpm's so quick you can't move the shifter quick enough, and no indication it's going to quit pulling even to 6500rpm's....FWIW.....Cliff

[ponyakr]

According to the Wallace site, an 067 cam was used in some 400's, after they were down to 7.6 CR. So, it looks to me like the 068 should be fine for a 400 with 9:1.

I've got some questions along these lines. When using the 068, because of press-in studs, would using Rhoads lifters be similar to running a low lift, steep ramp cam, up to about 3000rpm or so. In other words, would this be a decent combo, for a low budget, low compression, press-in stud engine.

My next question is: about what is the aprox max lift and spring pressure that is SAFE to run, with press-in studs. Don't know what the biggest cam and spring pressure that Pontiac used with press-in studs was ? Anybody know ? What is the min pressure that is safe to run, with an 068 and press-in studs ?

[Tim Corcoran]

For an 068 with press in studs I would not run over 90lb. on the seat. From the factory they had about 80lb on the seat. I would not run Rhoads but would run Hy-Lift Johnson 951-R lifters.

[tom s]

What did 63 421 HOs run for seat pressure?I know they had dual valve springs with the pressedin studs?Tom

[Burningbird]

I had the 068 cam in my previous 350 with only 8.6:1 SCR. It actually run pretty decent. Now I have that same cam in my 406 with 10.1:1 SCR, 1.65 rockers and ported #16 heads, wish I had gone with a little bigger cam. I believe that in a 400 with 9:1 compression that cam will work just fine if you don't want to convert to screw in rocker studs.

[dadsformula]

I have used the 068 in 2, 400's and my current 455, I have always been one of those
believers that Pontiacs engineers (and in particular their Cam designers) knew what they
were doing. It's a great street Cam, and my engines ranged from 9:1 to 9:6 in
compression. Very easy on the valve train, and designed to allow a warranty on the
engine and Vehicle. 40 years of evolution I am sure provides better alternatives
and can produce more Power, but for a reliable street engine with a good sound and
great low and mid range power, pretty tuff to beet the 068. I will also admit that
I have never been a fan of any part forcing the replacement of others as many modern
grinds can do. So some of this response should be viewed with my bias in this area
as lots of guys correctly view this as a challenge and not a pain in the ass as I do.

None of this will matter if they keep changing the Oil formula's as we are already forced
to use crazy methods to insure breakin and even normal use with these Flat Tappit designs. We will all be faced with using Roller designs if any more changes are made.
Most TV shows just go right to the LS motor, and don't even bother with the original
power plants.

[Pontiac Derek]

066 cam 111 LSA
067 Cam 113.5 LSA
068 Cam 116 LSA
744 Cam 115.5 LSA
041 Cam 113.5 LSA

Thats the correct LSA specs for those cams, they all worked well for their designed application!
068 cam is a Great Street Cam in almost anything with 8.5:1 on up
People get Wayyy too caught up on the LSA its just a number
The Valve Events are what you need to be looking at!
First you need to know what engine, what it will be used for, how much power do you want to make?
Then what car,drivetrain,stall converter, Gear Ratio?
Cams with Fast Aggressive Lobes Will Make More Power BUT the Valvetrain Must be set up for them ie- Beehive Springs, Titanium Retainers, light weight valves, all of that is needed Plus the Correct Size of Lobes are needed to Maximize power and rpm output
If you just stab in an XE or Voodoo cam with regular old valvetrain parts they will fall on their face at high rpm!
Yes the Voodoo cams are much better than the XE cams But you still must put some real attention into the valvetrain in my Experience
Then if you choose one based on @ .050 numbers chances are it will be too small for the application.
This is Partly Why a certain type of cams work better in Pontiacs
If you don't want to build a custom deal you are better off Using Factory type cams or as some say Old tech cams, don't let that fool you though! A properly setup Old tech cam Will Eat a Wrongly setup New tech cam all day long!
This is where i say if you want new tech go roller its not much more money, especially if you burn up a new tech cam on break in!
I have heard somewhere that Engineers know best and don't change that LSA or Else, LOL Thats Total you know what! If you're builder cant design you a better cam than the catalog grinds you probably should go elsewhere!!!
JMHO

[Stan Weiss]

Opening or closing the LSA will increase or decrease overlap. If because of CR you want to adjust IVC. You can degree the ICL to something other than the same as LSA.

Stan

[johnta1]

Adding to Derek's chart:

___________________ ADV Dur___Overlap
066 cam 111 LSA ____ 273/282 __ 55
067 Cam 113.5 LSA __ 273/289 __ 54
068 Cam 116 LSA ____ 288/302 __ 63
744 Cam 115.5 LSA ___ 301/313 __ 76
041 Cam 113.5 LSA ___ 308/320 __ 87

The overlap/duration play into it.

The intake closing point would be what makes it 'think' the cr is higher.
As Stan said, degree it with a sooner closing point would make it seem higher, but may make every other cam points way off.

[Ben M.]

Originally Posted by ponyakr

So, it looks to me like the 068 should be fine for a 400 with 9:1.

I used an 068 in a 400 at 8.5:1 with Melling made in USA lifters and it ran great, perfect street manners and plenty of get up and go. Was done around 4500RPM, and only found that out after missing a shift in a 3.55 rear end setup car. With a 2.56 rear end it was a great driver on 87 octane.

I'm putting one in a 455 I have now because I don't want to upgrade to screw in studs as we're on a budget trying to get the car back on the road.

I don't think you can beat a 068 cam in most applications that aren't pushing the envelope while still using known-good factory parts.

[mgarblik]

The 068 cam was a great factory camshaft for it's day, no argument there. Excellent balance of driveability, valve train life, quiet operation. That's why it has been the staple of Pontiac street performance for decades. They are also very inexpensive. I think you will give up a little low end power at 9.0 CR as stated. All that being said, this is 2016 and there are literally dozens of camshafts from most aftermarket companies that will out perform the 068. After all, they have continued to develop the camshaft the past 50 years. One I really like and have used is the Ultradyne 276-284 on a 112 LCA. It made right at 20 more HP peak than the 068, 16 more average HP, 2000-5800 in a 400. Very smooth, lots of vacuum, 20" @ 1000 RPM. This is just one example, there are many, many others that would produce similar results. If I had an 068 laying around and wanted about 330-350 HP out of a stock 400, I would throw it in there. Better choices are available.

[ponyakr]

"... i am going to get an 068, mainly cause of the lower lift for my pressed in studs..."

This is a quote from the OP. So, which of the modern cam grinds will work, SAFELY, with press-in studs ?

I think that is the question. I don't think anybody doubts that there are LOTS of cams that will make more power than the 068. BUT, if you use enuff spring pressure for these newer grind cams, will a stud be in danger of pulling out ?

Can you get by with 100lbs + installed and near 300 open ?

And, some guys here recommend using a stronger spring than you really need, because they will lose some pressure, with use. A pulled stud, on a running engine is no fun.

[Will]

Originally Posted by mgarblik

The 068 cam was a great factory camshaft for it's day, no argument there. Excellent balance of driveability, valve train life, quiet operation. That's why it has been the staple of Pontiac street performance for decades. They are also very inexpensive. I think you will give up a little low end power at 9.0 CR as stated. All that being said, this is 2016 and there are literally dozens of camshafts from most aftermarket companies that will out perform the 068. After all, they have continued to develop the camshaft the past 50 years. One I really like and have used is the Ultradyne 276-284 on a 112 LCA. It made right at 20 more HP peak than the 068, 16 more average HP, 2000-5800 in a 400. Very smooth, lots of vacuum, 20" @ 1000 RPM. This is just one example, there are many, many others that would produce similar results. If I had an 068 laying around and wanted about 330-350 HP out of a stock 400, I would throw it in there. Better choices are available.

QFT

A cam like the Crower 60918 I mentioned will produce more power overall than the 068 in a low-medium compression 400 while still having a very mild idle and plenty of vacuum. You do need something other than stock springs though. If you don't mind upgrading valvesprings all other stock valvetrain parts will still work with it.

If you have pressed studs, stick with the 068.

[mgarblik]

I understand your concern about the studs. My experience may differ from many others here but I have rarely had studs pull out of Pontiac heads with cams under .500 lift and 130 lbs. on the seat. But that doesn't mean they can't. During the cleaning process of a head where the oven and blasting process is used, those studs become almost impossible to remove! Have broken quite a few just trying to pull them out. I have also successfully drilled and pinned pressed-in studs in Chevy and Pontiac heads. Heads have to be removed of course. There is nothing wrong with an 068 cam. Has to be one of the best factory cams from any manufacturer.

[PAUL K]

Originally Posted by mgarblik

I understand your concern about the studs. My experience may differ from many others here but I have rarely had studs pull out of Pontiac heads with cams under .500 lift and 130 lbs. on the seat. But that doesn't mean they can't. During the cleaning process of a head where the oven and blasting process is used, those studs become almost impossible to remove! Have broken quite a few just trying to pull them out. I have also successfully drilled and pinned pressed-in studs in Chevy and Pontiac heads. Heads have to be removed of course. There is nothing wrong with an 068 cam. Has to be one of the best factory cams from any manufacturer.

X 2 !

[ponyakr]

"...I have also successfully drilled and pinned pressed-in studs in Chevy..."


Yeah, I pulled a stud on a 350 sbc, in a '74 2-ton truck. Drilled it with a hand drill, and pinned it, still in the truck. Hey, I had clabber to haul. Didn't have time to pull the engine.

Below is a pic of the 1st refer truck I drove, at age 6. It was a '53 model. Finally sold it for scrap iron just a few years ago.

[bullheimer]

that's kind of funny, because the whole reason i posted is because i bought this cam:
"Ultradyne - 280 288 223 231 .460 .490 110 Great street performance"
and i don't want to have to put screw in studs in.
it has that 110 lobe sep and i have stinkin 8 brow pistons that everybody says are detno bombs. however, i do have 061 open chamber heads, too. cr is 9.1 maybe even 8.9:1 i think also that this cam's 110 ls would like a higher c.r.