[n20ta2]

My 461 is in the final stages of assembly at my local machine shop and the cam I had purchased used here a couple yrs back is bent and can't be used. It must have come out of a engine that kicked a rod or somthing.
I had built my whole combination around it so looking for a recommendation based on what I have. Cam was a custom HR butler grind specs are:
571 571 lift
110 lobe separation
266/ 270 .050 duration
No rockers yet was going to use 1.65 ratio.
This will be an aggressive street car with some track use.
1969 gto 461 forged internals, 10.75:1, compression 0 decked, kauffman highports as cast (kauffman matched the springs to my cam specs) Northwind intake with either a 950 hp or a 1050 dominator.
I have a continental convertor that stalls around 3800-4000 and I'm going to use a 12 bolt with 3.55 or 3.73 gears with a th400. My rear tire is a 295 drag radial. I have howards roller lifters that came with the cam. They seem fine. Any advice is appreciated.

[tom s]

Just me,I would hate that cam in much street driving at all.Power brakes?Tom

[n20ta2]

Yes power breaks.
I don't ming going milder if I can still use my combo, I had already considered going milder as this will see some street use. I'm also worried about the rash of roller lifter failures as of late, don't know who makes these howards lifters but they are at least 4 yrs old with supposedly not much use.

[Steve C.]

If necessary use a electric vacuum pump for the power brakes.

Example here, and only one of many out there....

https://leedbrakes.com/i-23439165-el...it-series.html

Years ago when I had power brakes I used a unit from Master Power Brakes. It was hidden in the fender. With my exhaust system I couldn't hear it when the car was driven.


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[Stan Weiss]

With the limited specs and goals. It is hard to say. But a guess would be something like the SD road paver.

Stan

[Steve C.]

Dave Bisschop's Road Paver has 306/314 rated duration and 246/252 at .050".
It has quite a bit of lobe lift with 0.4000", and ground with a 112 LSA.

Cliff Ruggles helped Ray Klemm build his '69 Firebird with the Road Paver Hydraulic roller cam, but using solid roller lifters with it. And if memory serves me right Ray and Cliff touted it as a street car. It was featured many years ago in HPP magazine Pavement Pounders Shootout. It was a 455 based combo (462 cid) and had 260 or 270 cfm iron heads with quite a bit of compression at the time and running race gas. He used a modified factory intake and headers, after time it went low 11's with the combo at a 3,555 lb race weight, TH400 and 3.70 gears.

Later Cliff was weaning it off of race gas, and tuning it for pump gas with some changes.

https://www.motortrend.com/news/hppp...9-pontiac-gto/


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[n20ta2]

Just got off the phone with Jeff Kauffman and he recommended somthing similar in duration to the road paver at around 250 255 duration on a 110 lobe separation with lift a little higher at around 600. He had somthing on the shelf he is sending me with somthing close to those numbers. I think the 600 lift is with 1.65 rockers, think the extra lift is to take advantage of the highports?

[leeklm]

I would look into Dave's Old Faithful 2.0, which Dave mentioned made as much or more power as the Roadpaver in his combo with 310cfm heads.

I forget exactly what my vacuum readings are, but it should operate brakes just fine. I can check again later if you like...

With the combo in my signature I just turned a personal best last week of 10.25 @ 130.xx mph with a foot brake and excellent street manners. The car is truly a sleeper! Time slip attached...

On the dyno this combo was turning out 600/600

Sent from my SM-G965U using Tapatalk

[pastry_chef]

Originally Posted by leeklm

made as much or more power

Sounds pretty vague..
I also wonder what the intake and head flowed bolted together. If they went 310 in tandem it would like the larger cam, peak HP should be north of 6000 RPM.

High ports will want a big stick, much more than the d-ports.

[tom s]

A road Paver with solids for sure would be a good 455-461 street cam.Take 8 degrees of the 50 number because of the solids and your near a OF with hyd rollers.Tom

[Steve C.]

Keep in mind those High Port heads flow right up thru 0.700" valve lift. They will thrive on as much valve lift as mechanically possible.

Side note- Duration on the OF 2.0 cam is 236/246 and the lobe lift is 0.3910" / 0.4000"

If you dig deep enough you can determine the lobe numbers used.

[Steve C.]

"Just got off the phone with Jeff Kauffman and he recommended something similar in duration to the road paver at around 250 255..."

With that in mind, for conversation.....

For the intake side, the lobe used on the Road Pavers exhaust.

Comp Lobe 3116B
314
252
169
0.4000" lobe lift

Then pick a exhaust lobe that suits the cylinder heads exhaust-to-intake flow ratio and also taking into consideration the complete exhaust system on the car, and the use.


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[JUDGE3]

Tom Wilhite picked this cam for me. at first I was bugged thinking to big. its perfect. I love it. will go with it again should i need to build again. 455/round port e heads.

SERIAL # Y 7369 SPEC CARD # 032494 SPEC CARD INQUIRY BY SERIAL #

PART # 51-000-9 CAMSHAFT, P8 PONTIAC V8 265-455 1955-81

CORE C51-9B CAMSHAFT BLANK, P8 PONTIAC ROLLER, 8620 Special Grind

GRIND # P8 3317S /3318S HR110.0

DURATION @ .050 INTAKE 242 ROCKER ARM RATIO

VALVE ADJ INTAKE .000 DURATION @ .050 EXHAUST 248 INTAKE 1.50

VALVE ADJ EXHAUST .000 LOBE LIFT INTAKE .3600 EXHAUST 1.50

VALVE LIFT INTAKE .540 LOBE LIFT EXHAUST .3750

VALVE LIFT EXHAUST .562 LOBE SEPARATION 110.0

DURATION .006 INTAKE C/L 106.0

TAPPET LIFT INTAKE 293 CAM ADVANCE 0

TAPPET LIFT EXHAUST 300 HYDRAULIC Y

VALVE TIMING .050 OVERHEAD CAM N

VALVE OPEN INTAKE 15 JOURNAL DIAMETER STD 1.899

VALVE OPEN EXHAUST 58 RECOMMEND VALVE SPRINGS

VALVE CLOSED INTAKE 47 DEPARTMENT R

VALVE CLOSED EXHAUST 10 SPC INSTR FOR CUSTOMER

[grivera]

Originally Posted by leeklm

I would look into Dave's Old Faithful 2.0, which Dave mentioned made as much or more power as the Roadpaver in his combo with 310cfm heads.

I forget exactly what my vacuum readings are, but it should operate brakes just fine. I can check again later if you like...

With the combo in my signature I just turned a personal best last week of 10.25 @ 130.xx mph with a foot brake and excellent street manners. The car is truly a sleeper! Time slip attached...

On the dyno this combo was turning out 600/600

Sent from my SM-G965U using Tapatalk

Wow! That is really impressive. Is the OF2 on Xtreme Energy lobes?

[slowbird]

We made 610hp/640tq with 243-249 .630lift. Im a fan of modest duration and as much lift as possible.

[ta man]

Originally Posted by slowbird

We made 610hp/640tq with 243-249 .630lift. Im a fan of modest duration and as much lift as possible.

X2 Especially for a street build that wants to run the numbers at the track. Use that available flow at higher lifts..that's why Lee's car runs so well for a mild street engine..flow and lift..plus it's light!

[tom s]

From Joe Sherman(RIP)The better the head the less cam you need to reach a target HP.FWIW,Tom

[Steve C.]

"If you want to build a street motor with the most power without a sacrifice of idle and low speed qualities, then lift is the most important factor to maximize, not duration. The best street cams are those that seek to maximize lift while only adding a minimal amount of duration."

David Vizard


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[1968GTO421]

Originally Posted by slowbird

We made 610hp/640tq with 243-249 .630lift. Im a fan of modest duration and as much lift as possible.

Agreed. A local race engine bulder told me that it's lift that produces power and duration sets the power range RPM's. He showed me the rule book for the local circle track where certain classes limit lift to .420-.450" with no restriction on duration. He said this was to keep speeds down by limiiting power.

(Please, no debates about how Pontiac factory cams produce good power with very little lift, Thanks)

[n20ta2]

Originally Posted by slowbird

We made 610hp/640tq with 243-249 .630lift. Im a fan of modest duration and as much lift as possible.

Makes sense, guess that's why Jeff wanted to see around 650 lift and the duration isn't to crazy. Interested to see what he is sending me, I will post up the cam card when it arrives.