You are correct. The first one is a little more street friendly, due to the lesser duration, as well as a wider lobe separation angle, which decreases the amount of overlap between the valves. It also has a split pattern, with slightly more lift and duration on the exhaust lobes, which aids in increasing the exhaust flow and cylinder scavenging.

 

+1

Both cams are not very far apart, not a huge jump in either direction.

I agree with the first cam being the choice for two reasons,
1) Mainly used for street driving and you want as much vacuum as possible
2) You are running the smaller of the CID BBC's

If you were building a bigger CID BBC you could get away with the bigger grind and be just as happy. Big cubes make big cams seem smaller.

 

So I'll be happy with the first cam? I'd imagine it has a pretty good lope at idle. I just don't want to wish I went bigger. Thanks guys

 

I honestly don't think you'd be unhappy with either one, they are not radical cams. For the way they sound, the second one should be somewhat noticable, the first not as much.
But based on your statements about wanting the most vacuum the first cam makes more sense. Everything is a trade-off.

I've driven 292 and 305 versions (Comp Cams hydraulics) on the street before and they were more towards the radical side of things. But by todays standards, what's too radical for the street, LOL?

 

It will have considerable lope and bottom end grunt. The only thing you'll wish you went bigger on is rear tires.

 

Ok so either one will work. With the second one, will I have enough vacuum to run my power brakes and power steering as well as my vacuum secondary on the carb. I am for sure leaning toward the first option as you guys have suggested. I don't know much about cams so I'm trying to learn as much as possible.

Thanks guys, Mike

 

Call the tech dept for the cam company, they should be able to give you an idea of what range the vacuum should fall for your engine, it is their cam. They'll give you a round about range as a good assumption based on their experience with it. They' also tell you what I'm gonna tell you, it really depends on how you time the cam (advacned 4 deg, straight up, retarded 4 deg), how well it's tuned, how loose the converter is at idle, what accessories will be run that work the engine and alternator at idle (a/c, big stereo, etc), what you set the idle rpm to (650, 700 ,750, etc), where you set the ignition timing, temps (air and engine), oil pressure, engine oil weight (thickness), and so on. All these have some affect on idle load.

The '72 El Camino I sold years ago had a 396 cid bbc in it with 10.25:1 compression with a mechanical cam along the lines of this in it (see attached pic). I don't remember if this is the exact part number as it was 20 years ago. But the specs look like it. I ran this cam on the streets with no probelms on a vacuum boosted brake system and all accessories. Had no problems what so ever. While you're driving the vacuum is much higher and gets stronger on deceleration when you need the brakes anyway. You could always just add a vacuum reservior if it really bothers you.

What are your plans after the the cam? What is the end game for the car? Will it move into more of a dual purpose street/strip vehicle? Reason I ask is it's easy to get caught up in the incremental parts climb which cost more money in the long run. Trust me, I've been there.

 

I really can only see myself taking the car to car shows. It's never going to be a race car. I just want a fun street driver and something that has plenty of get up and go. I had to fill out the form for all of those accessories that you listed above and they suggested both of those cams. I could see later down the road putting heads on it. It's a llong-term project. I just ordered Lakewood traction babareven tho it has nothing to do with the cam haha

 

If you go with the first cam listed (which I think is the better of the two most likely) be aware that cam is already advanced four degrees.

One thing that many people don’t understand is a technique used by most manufacturers to grind-in advance into the camshaft. A quick way you can tell if the cam has been advanced is to compare the lobe separation angle (LSA) to the intake centerline. If the cam is ground “straight up”, then these two numbers will be identical. you can see the LSA and ICL are four degrees apart, in this cam the advance is actually ground in.

I would install it using the recommended 106 degree intake centerline I would not advance it any further.

 

X2

 

I love all the advice guys! Another cam suggestion came up as this one. It's a non voodoo cam
http://api.viglink.com/api/click?fo...w.chevelles.com&txt=http://www.lunatipower.com/Product.aspx?id=2116&gid=278

 

Sorry here is the linkhttp://www.lunatipower.com/Product.aspx?id=2116&gid=278

 

Sorry here is the link http://www.lunatipower.com/Product.aspx?id=2116&gid=278

I recognize those specs. I'm pretty sure that is a Harold Brookshire design, one that he brought over to Lunati after the IRS shut down his UltraDyne Cams.

A good friend of mine ran that in a 455 Pontiac, in a '65 GTO with a Doug Nash 5spd., with ported factory iron heads. It was a daily driver car for him, and he ran lower-12s with that cam.

Maybe install it on a 108 or 109 ILC, and pick up a few hp on the top end.

 

Comp Cams considers their 280 adv duration ( 230/230 @ .050) to be the most duration for vacuum on brakes etc.

 

The Voodoo cams are a newer design. The Bracket Master and Street Master lines have been around for a long time and use older lobe designs. The Voodoo cams will normally run better as long as you match everything correctly.