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-   -   068 cam versus 067 versus 744 (https://forums.maxperformanceinc.com/forums/showthread.php?t=583158)

fredjchavez 12-16-2008 12:54 AM

068 cam versus 067 versus 744
 
Wondering what people think regarding 068 cam with my setup:

68 vert, 16 heard, thd 400, 2.93 gearing, power brakes, etc...

067 cam is done at 4600, and i've got more torque that i know what to do with. Does anyone know if the vacuum brakes will still be 100%?

Any suggestions would be welcome. BTW, I like the setup and the only plan might be a convertor change since this is driven at hwy speeds most of the time. Thanks.

Will 12-16-2008 01:50 AM

Of those three, 068 for sure.

66GTO Jim 12-16-2008 11:04 AM

Lot's of vacuum, with an 068 in that engine combo. Jim

Ron H 12-16-2008 11:10 AM

If you are changing converters, buy a good one.
You could stretch the 744 out if you wanted. But the 068 is the sure bet performer. Still done by 5200, but if all is stock, it is safe.

OINK 1 12-16-2008 01:26 PM

744 cam/ Pontiac Gregg
 
The old McKeller cam is a nice unit. The lobes look like they're for a roller cam! Really long fully open duration #'s. BUT, I'd get an Ultra-Dyne 280/288, it will give 30 more horse !

Pontiac Gregg
1-303-776-0877

Region Warrior 12-16-2008 05:01 PM

On that 30 more horse, is that peak?
Or over a broad rpm range, like 3000?

fredjchavez 12-17-2008 12:14 AM

Thanks guys. I am open to suggestions but wanna keep my power brakes. Years ago, I had a w30 cam in a 455 and slow and cold were very scary stopping events (there was this delay as I pushed the brakes). I had thought the 068 to be low on vacuum and potentionally marginal for me, but will probably give it a try. I look at ultradyne 280/288 and probably do full circle again before ordering.

If I need more cam from whatever I select (leaning toward 068), I probably will plan for 1.6+ rockers which will make the cam events look 4-5 degrees longer.

PITTSBURGH 64 12-17-2008 06:00 AM

Checkout the Nunzi 2041 or the Crower 60918...
http://www.nunzi-pontiac-expert.com/camshafts.htm

scott mills 12-17-2008 09:08 AM

1 Attachment(s)
I am by no means a expert, but I did plug the cam numbers into DD200. You may want to look at the summit 2801. At $59 dollars it is hard to beat. In the picture the 067 is first, 068 second and the 2801 last. From what I see on the charts is that the summit cam will move your horsepower higher in the rpm's. Just a thought.

fredjchavez 12-17-2008 10:32 AM

Thanks for the crunching. Looks like the 067 is really great if you want lots of low end torque and power fast!

I do like the torque curve of the 2801. Thats one that I have come to several times. That is certainly a good option providing the intake valve closes after that of the 067 thereby offering less dynamic compression in the highway driving rpm range.

Given the sad state of oil/flat lobes, a cheap cam is value in itself!

Overkillphil 12-17-2008 11:10 AM

Been down this road with 400's and these cams in the past. The 067 is great in the 350 Pontiac, but too mild in the 400, as you have discovered. The 068 is fine (still mild but not as mild as 067) and your brakes will have no problem either.

I like the Nunzi 2041 cam much more than the 068. It is a better version of the 068 but with higher lift and tighter 110 lc. If you tune it right, your brakes will be fine with this one as well.

I never liked the 744 personally.

BTW, Nunzi once told me the 067 in a 400 is like putting a "broomstick" in there! :D That man has such a way with words!

getmygoat 12-17-2008 03:34 PM

60916
 
The crower 60916 could also work, although your rear gear is a little low (numerically) for it. If you had a lose converter you'd be ok. Plenty of vacuum for power brakes.

PITTSBURGH 64 12-17-2008 06:30 PM

BTW, Nunzi once told me the 067 in a 400 is like putting a "broomstick" in there! :D That man has such a way with words![/quote]


Phil, back in the seventees we use to pester the hell out of him. One time he said over the phone, "your car will go faster if you quit smoking that stuff"...:D

se428bandit 12-18-2008 01:10 AM

I have always liked the 744 cam but with a 2:93 gear it would be a pig out of the gate.I use it with a 3:42 gear [400 6x "4"] and adv the cam 4 degrees [1.65 rockers on the exhaust/1.5 on the intake] and a 2600 stall and it ran very well.Driving it 110 miles[1 way] to the track it ran an 8:68 @ 82 MPH on P275-60 radial tires with a WAY to small elderbrock 600 cfm carb.

69Customs 12-18-2008 12:14 PM

Hey Scott Mills,

Could you plug in the 2800, 2802 cam numbers into that same combo into the DD200 to compair. I would like to see where they fall in comparison.
Thanks

scott mills 12-18-2008 02:50 PM

1 Attachment(s)
Here you go. The first chart says 068, but it is the Summit 2800 numbers.

69Customs 12-19-2008 03:07 PM

Hey Thanks for the info Scott. That is interesting. looks like the 2800 acts just like the 067 but the 2801 is a little stronger that the 068 in that perticular set-up.

95ramairformula 12-19-2008 05:08 PM

Scott
Real curious on how the XE 256 cam would fair against the 067, 068 and 2801.
Alot of people are using the XE's and swear by them. I figure the torque would possibly outshine the other cams, not sure about the hp.

If you get time could you run the cam and see what the XE 256 cam would do in a low compression 400. ... 8.1.1

Specs are 212 intake/218 exhaust at .050
Valve timing: at .006
Intake 22 BTDC 54
Exh: 68 BBDC 20
LSA is 110

valve lift is .447 intake and .455 exhaust
Lobe lift @ .050 is intake .2980 and exhaust .3030

Thanks a bunch if you could do this.

fredjchavez 12-19-2008 06:15 PM

For the combination above, 252 probably would not work well.

Looks like the 2801 and 068 are keepers along with anything else that has similar duration and intake closing events.

Thanks guys for the conversation!

scott mills 12-19-2008 06:30 PM

1 Attachment(s)
Here is the XE256 with the summit 2800 and 2801. All at 8.1 compression ratio.


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