Z-11 Cam Profile?

[RCE1962]

Well guys.....

I've investigated this to some degree. However, I've received conflicting information.

The Z-11 appears to reflect the best that a factory 409 can be, not including any mystery motor stuff.

Well..so-be-it. I like to hear the sound of that engine, and experience the HP and torque of that engine that was built over 40 years ago.

Did that engine really produce enough vacuum? with 2X4's and spark advance ETC. with that kind of "cam"? I would like to know actual lift and duration numbers and where to get such a grind if not available anymore on a factory level.

Any Z-11 specs would be appreciated.

Please Advise...

RCE1962

[models916]

560/560 290/290 110 Lobe Sep

[CDNpontiac409guy]

Original cam was:

.556" lift intake and exhaust... 250 duration @ .050" ( HUGE for a factory cam )
Ground on a torque destroying 113.5 lobe centre separation angle. This wide angle DOES provide better idle vacuum, and I know for a fact that the cam was used with power brakes in the 1964 & 65 cars.

ABSOLTELY no need to resort to this archaic cam profile, when there are so many superior modern profiles to choose from ( unless of course you are re-assembling a genuine Z11 engine ).

This profile was regular equipment in all 400 & 425 HP 409's built after mid November 1963.

[models916]

I think the one i listed previously is the Isky version of the z cam

[CDNpontiac409guy]

Ah yes, Model, a better configuration indeed :deal
That one I just posted is the actual Z11 / Late 64-65 high horse. Factory cam is always a compromise.

[Ronnie Russell]

Aubrey, I think " Canadian Praries" must be an accurate discription of your locale. Is it true , letters and packages are still delivered by horseback up there?

[CDNpontiac409guy]

I don't know about horseback, Ronnie....
but does this answer your question about the "Canadian Prairies ? ;)
( having a break, parked on the side of a secondary highway, about 45 miles from my house )

[Ronnie Russell]

Aubrey, Hope you know that was said " in good fun". That definitely looks like prarie!!!! Sorry for getting off the subject. It is too hot to go outside.

[RCE1962]

Aubrey.

That 35' Ford, with that flathead, is a jewell.

My Brother had a 1950 Mercury Coupe (acquired in the mid 1970's) with a 255 flathead with a column 3-speed with overdrive. It was like (Hi-Lo) 1-3 and 4-6 gears. It already looked "chopped". Crank the window down about 3½ to 4½ turns. Big/Heavy guage metal exterior sheet metal. Very Nice ride.

I find that I like most, if not all, cars in their original state, if possible. That said...I Like that coupe. Awesome!!

Ron

[RCE1962]

Back to cam profiles that are superior to the original Z-11 factory cam.

Opinions? Is the Isky version, mentioned by "models916" and which concurs with Aubrey's opinion on this, the last word? Any other opinons would be appreciated.

RCE1962

[Nuts]

Original cam was:

.556" lift intake and exhaust... 250 duration @ .050" ( HUGE for a factory cam )
Ground on a torque destroying 113.5 lobe centre separation angle. This wide angle DOES provide better idle vacuum, and I know for a fact that the cam was used with power brakes in the 1964 & 65 cars.



I wish I had enough technical knowledge to translate all this valuable information !! I have the Iscky (Z33) cam which I was told was the same as the Z11 cam. First off I don't have enough vacumm to run the power brakes, which is causing me some problems. Second I can't seem to get the idle set where it is both responsive to the throttle and will idle without help... What should the advance be set at ? What should the idle speed be ?

The car heats up very fast, from a cold start to 180* in less than 2 blocks. My over strenght cooling system will keep it at 180-190 while moving but she heats up to over 200* at lights or in traffic..

Any thoughts and advice is appreciate !!!!! :bow

[region rat]

I always thought the lift was only .525 with advertised duration around 290. Aubrey is correct about newer profiles. Technology has come a long way. I ran this cam years ago and ran 11.85, 118 @3900# and the cam was put in @ 110. It ran out of gas around 6200.If I wasn't so lazy, I;d mike one and let you know. The 550-560 lift might be with 0 lash. Memory is not my strong point. Bob

[Ronnie Russell]

region rat, I always check cam lift while I am indexing. Very simple procedure. Then multiply by rocker arm ratio to get advertised valve lift. Check cam card. Checks out on the money. Sadly however, measuring "true" valve lift with dial indicator on valve retainer, the measurment always comes up short. Even at 0 lash. Then measure with correct lash and measurment is really short. Some are probably thinking, pushrod length is wrong. Nope, The actual length always comes up short. Of course , you would never know unless you measure. Most buy a .550 lift cam and assume they get 550 lift. Sorry, it dont work that way.. Nuts, I hate to keep repeating myself , but it sounds to me that you dont have enough advance. or a carb "out of whack" Wished I could be more help.

[Nuts]

Ronnie,

I'm on the road and haven't had any obortunity to check the carbs. Just trying to get some things to check so that I can get them fixed when I get back to the house.

[CDNpontiac409guy]

Just SCREAM'N, Rat :beerbang :beerbang ... THAT's FAST :beerbang

Yes, you're absolutely right, that measurement is at zero lash... you lose .020"-.030".

NHRA / IHRA Stock spec checks the lifter at retainer movement with zero lash. My custom grind Stocker cam is "supposed to" provide .506" / .516" lift at the retainer. .... I get between .470" - .485". I'll be freshening this engine over the winter, installing a new cam with an "extra" .025" or so lift.


Sorry Nut.... I get spewing out these numbers, and I end up confusing myself most of the time :doh

[CHEV601234]

CDN,
I degreed an NOS Z-11 cam and it came out 4deg retarded. From your experience, was that ground into the factory cam or was it my timing gear set?

[CDNpontiac409guy]

I don't think the factory did that, Chev... but if you were using a factory double roller timing set, then yes, it would be about 4 degrees retarded.
The truck thing, ya'know :dunno

[CHEV601234]

Thanks CDN. Yeah, I know, but I'm using a new "true roller" with the crank gear installed on zero. Probably a bum gear set.... :dunno

[Ronnie Russell]

Chev601234, It is not unusual to come up with 4 deg. retard. Most likely the crank key-way is off a little. As you know, by reinstalling crank gear, you should get close to "dead on".

[SteveD409]

Running stock type wide lobe seperation in my car. Is this the reason it respondes slowly when I 'goose' it from idle and, also, doesn't have any power until over 3K? It screams after about 3K but under that I'd think the original 283/2 barrel would have stayed with it.

SteveD

[SS425HP]

Had the same thing with a Cloyes set. Put it in straight up, numbers were off. Retarded it 4 degrees, and numbers were right on. That's the value of checking cam timing. Had me going in circles for a while. Kept thinking I was doing something wrong. After checking it enough times, and doing an intake center line, I decided I was right and put it in on the retard keyway. Seems to work fine, now.

Fred

[jim_ss409]

Nuts, Your Z-33 cam has the same duration at .050 as the Z-11 cam but it has a much narrower lobe separation angle. It's LSA is 110 degrees while ths Z-11 cam has a 113.5 deg. LSA. The narower LSA means that there is more overlap time. The overlap time is the time when the intake and exhaust valve are both open at the same time. The exhaust isn't done shutting when the intake is starting to open. This overlap time works especially well on cars with headers because the outgoing exhaust will actually suck on the incoming air-fuel mixture during the overlap period and boost power. But, at an idle, when the exhaust isn't moving well the exhaust fumes tend to get pushed back through the intake valve into the intake manifold. So, cams with narrow LSA's tend to give you a rough idle and low vacuume. The Z-33 cam is a pretty big cam for 409 cubic inches. It will of course work but your carb. and ignition tuning will have to be right on and even then I doubt you'll ever have enough vacuume to comfortably run power brakes. I think Curt Harvey used to recomend the Z-33 for strokers and the Z-45 for stock displacement 409's. The Z-45 also has a 110deg. LSA but it only has 240deg. duration where the Z-33 has 250deg. I can't remember if you are running the stock displacement, 409ci. If you are it'll be hard to get the car to run well on the street with that cam.

[Nuts]

Jim,

Thanks for the excellent information and description of the cam and performance. I'm kind of dumb on how all this stuff works to make it go fast. What do you recommend for initial timing with the Z33 cam ?

[jim_ss409]

Without knowing how much centrifical advance is built into your distributor that's a hard question to answer. With a big cam you want lots of initial timing but if you go much beyond 16 degrees of initial advance it might be hard to start. I think that 15 degrees initial advance with another 20-21 degrees of centrifical advance would be about right. That would give you about 35 or 36 degrees total. You would also want all of the centrifical advance in by about 3,000 rpm. If you've got a dial back timing light I'd set the total timing at about 35 degrees. Depending on what springs are in the advance mechanism you might have to rev it pretty high to check the total advance. If the timing hasn't stoped advancing by the time you hit 3,200 you'll want to install lighter springs (they're under the rotor) so that the advance is all in by about 2,800 to 3,000rpm. Set it at about 35deg. Then let it idle and see what you've got for initial timing. If it falls between about 12 to 17 degrees that should do it. If it comes out at less you'll want to limit the amout of centrifical advance and if it's more than about 18 degrees it might be hard to crank over, especially on a hot day. A distributor with vacuume advance also helps smooth out the idle, if you've got enough vacuume to make it operate. You should always check the timing with the vacuume hose disconected and pluged. When you hook it back up the idle will speed up and smooth out. That's because the engine really needs lots of timing advance at an idle to run it's best. Aparently an engine with big heads and a big cam needs lots of initial timing because the air-fuel mixture is moving slowly, is not well mixed and is contaminated by exhaust gasses that get pushed back up the intake ports. This poorly mixed and contaminated mixture needs to be ignited sooner. Therefore more initial advance. By the way more initial timing will raise you vacuume just a bit.

[Nuts]

Jim,

Thanks for the detailed and helpful information. I checked the advance out today and it appears I've got 34 degrees of total advance. I didn't have a tach, but picked one up today and will install and check out the rest of your thoughts. The RPMs seemed pretty high, but without the tach it's hard to say when the advance was reached. I'll get back with an update ASAP.

I also set the initial advance at 13-14, it seemed to help the motor run alittle smoother at idale. Don't know if has helped the "running hot" issue, because I didn't drive it vary far, just around the block. Still have an oil leak from the pan area I've not sorted out and I hate to drive it very far. Just makes a mess of the whole underside of the car.

Thanks again for your detailed post, it was very helpful.... :bow

[Skip FIx]

My old Crane F-Nitro 310/320 .580/.590 was a pretty good thumper in my old 409. Not much bottom end but at 2500 came on hard and propelled my 64 to 12.20s @ 108 in Dallas in 1972 with 425 top end on a stock 340 hp short block.

I had another 09 with the Z11 cam that sounded pretty darn lumpy also.

I think looking at the Ultradyne(handled by Lunati or Bullet now) or new Comp XE lobes have the best technology for a flat tappet street/strip out there now.

[Wild Bill Burge]

Hey guys...reading some of your Z-11 cam numbers jogged my memory, just a little, as I'm 62 and well...Anyway, in '63 at age 19, I bought for my bench seat Impala an over the counter Z-11 cam. aluminum fan shroud at $9.00 a side, aluminum water pump that leaked and front bumper. But of course my parts counter and use to be good friend got fired for his efferts. And maybe selling me it all at wholesale! The only options besides the 425 engine was power brakes and an AM radio. About that vacumn with the Z-11 cam... yeah, not a whole lot and a
lot less then with the 425 cam. No low end torque so had to spin the engine with 456's....about 7 sets to be exact. I still have that original cam and Oh yeah, a #7 piston with intake valve stuck through it...somewhere! Wonder where that $18 shroud is?

Wild Bill Burge
"The Living Legend Z-11

[skipxt4]

I still have my Z-11 cam from the sixties. (not using it though) I agree with all comments regarding no, low end torque.:clap But after the engine hit 3000, hang on. I installed a power brake booster, but the brake pedal was always hard. I can still recall my engine burning my eye's, while idleing and fouling the plugs, if I didn't pound the crap out of it, everyday. It definately wasn't a street friendly cam.:doh If I didn't burn Sunoco 260, my car would buck me around, like I was on a buckin bronco.:rofl Like Jim and Aubrey said, cam technology has come a long way, since the sixties. This time around, I'll be using an Isky. The Z-11 cam will just be a memory, from my previous life. Skip:)