How much cam is too much?

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rdkonkel
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How much cam is too much?

Post by rdkonkel » Tue Jun 19, 2018 11:41 am

Building a 9.5:1 sbc 406, afr 220 heads, edelbrock dual plane intake, 1-3/4 headers, 750 holley, in a street el camino, (no racing just street bashing)
I want to get the most driveability and still have good horse power. Will limit it to 6,000 rpms (so it lasts longer)
Question: how much cam can i use? I know most will recommend a 1,000$ roller but is it that mych better than a good hydraulic flat tappet?
Or have the rollers evolved so much that you can use a high lift and still be streetable?
(No gears/stall in this car. But 4 speed auto with low first gear)

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Re: How much cam is too much?

Post by mag2555 » Tue Jun 19, 2018 12:07 pm

For a all around fun street drivable car with your cid and heads I would not go over 225 duration @.050", with a lift of .500" with 1.5 rockers.
With a Cam like this if you find you can deal with more Cam for more power then you can then step up to higher ratio rockers for more lift and duration.

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Re: How much cam is too much?

Post by rdkonkel » Tue Jun 19, 2018 12:54 pm

It’s been along time since I’ve had a Street motor that wasn’t an LS. I built a 355 with a 488 lift thst was a dog 20 years ago, and currently have 6.0 in my truck with a 617 lift
Cam with great low end power. Can that be accomplished on a small block Chevy ?

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Re: How much cam is too much?

Post by lefty o » Tue Jun 19, 2018 1:17 pm

you can definately make low end power, imo your looking at something in the 230degr range and about .525" lift with a flat tappet on about a 108lc,but honestly id consult with whomever is your favorite cam guy. id consider a hyd roller for what you want, then you can run quite a bit more lift and actually use the heads you have.

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Re: How much cam is too much?

Post by 67RS502 » Tue Jun 19, 2018 2:15 pm

Sounds like a larger version of my 383.
I'd bump the comp some tho.
My cam is 224/224, made 483hp/495tq with a dual plane, daily driver streetable.
With that low a comp I would go over 230s duration.
67 camaro
girly rollers on pumpgas:
420 - 641hp BretBauerCam, 1.39, 9.79 @ 137.5
383 - 490hp 224/224, 1.56, 10.77 @ 124.6
502 - 626hp 252/263, 049s 1.44, 10.08 @ 132.7
62 Nova cruiser
383/200-4R/12-bolt w 373s
224/224 HR cam
1.57 10.97 @ 121.2

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Re: How much cam is too much?

Post by 67RS502 » Tue Jun 19, 2018 2:17 pm

lefty o wrote:
Tue Jun 19, 2018 1:17 pm
you can definately make low end power, imo your looking at something in the 230degr range and about .525" lift with a flat tappet on about a 108lc,but honestly id consult with whomever is your favorite cam guy. id consider a hyd roller for what you want, then you can run quite a bit more lift and actually use the heads you have.
More lift? ... and I thought you cant run more then .525" on the street :lol:
Sorry couldn't help myself :wink:
67 camaro
girly rollers on pumpgas:
420 - 641hp BretBauerCam, 1.39, 9.79 @ 137.5
383 - 490hp 224/224, 1.56, 10.77 @ 124.6
502 - 626hp 252/263, 049s 1.44, 10.08 @ 132.7
62 Nova cruiser
383/200-4R/12-bolt w 373s
224/224 HR cam
1.57 10.97 @ 121.2

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Re: How much cam is too much?

Post by lefty o » Tue Jun 19, 2018 2:29 pm

67RS502 wrote:
Tue Jun 19, 2018 2:17 pm
lefty o wrote:
Tue Jun 19, 2018 1:17 pm
you can definately make low end power, imo your looking at something in the 230degr range and about .525" lift with a flat tappet on about a 108lc,but honestly id consult with whomever is your favorite cam guy. id consider a hyd roller for what you want, then you can run quite a bit more lift and actually use the heads you have.
More lift? ... and I thought you cant run more then .525" on the street :lol:
Sorry couldn't help myself :wink:
i know, some people just cant help themselves, but he was asking about a flat tappet, so i based a recommendation on that!

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Re: How much cam is too much?

Post by cstraub » Tue Jun 19, 2018 4:54 pm

Based on the max of 6000 rpm, your better off with a 195 head for greater and broader power under the curve.
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Re: How much cam is too much?

Post by cstraub » Tue Jun 19, 2018 4:56 pm

The semi custom hyd roller cam I do for most 3.75 Stroke SBC with AFR 195 heads is :

.548/520 with 1.5 Recommend 1.6
233/235 .050
108 LSA
Last edited by cstraub on Tue Jun 19, 2018 4:59 pm, edited 1 time in total.
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Re: How much cam is too much?

Post by rdkonkel » Tue Jun 19, 2018 4:59 pm

Is that hydr roller?

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Re: How much cam is too much?

Post by cstraub » Tue Jun 19, 2018 5:10 pm

383 pump gas with that camshaft and AFR195's OTB
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Re: How much cam is too much?

Post by PackardV8 » Tue Jun 19, 2018 5:27 pm

In a strictly street car, torque you can use all the time; top end horsepower, seldom-to-never. Too much cam takes away more in driveability, low fuel economy, low vacuum, short guide and spring life than it gives back in usable performance. Stay away from the ragged edge of lift and duration. You'll be glad you did.

And yes, agree with Chris; for strictly street, consider the 195 heads. Again, more of everything you can actually use.

Just an hour ago, I was creeping through stop-and-go traffic alongside a '39 Chevy coupe with a BBC tunnel ram, too much fairgrounds cam and some type automatic transmission. He was lurching along dragging the brakes, smelling rich, bucking against the converter when stopped. Didn't look like a fun ride to me.
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Re: How much cam is too much?

Post by bigblockmopar » Tue Jun 19, 2018 5:30 pm

I'm reading stock stall convertor right? Any power brakes?

Mopar Performance used mention that their 284 adv. dur. Purple cam was roughly the largest cam that could be used with a stock torque convertor.
I think they were fairly right at the time.

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Re: How much cam is too much?

Post by Headguy » Tue Jun 19, 2018 8:31 pm

cstraub wrote:
Tue Jun 19, 2018 5:10 pm
383 pump gas with that camshaft and AFR195's OTB
That should be great on fuel economy ;)

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Re: How much cam is too much?

Post by Headguy » Tue Jun 19, 2018 8:37 pm

Yes, those 220 cc heads are just WAAAY to big, it will lose so much down low power you won't be able to drive it. Even with the 23 extra cubes.

If I were you I would get some 195 and full them in till they're about 160cc.

Then when you want to go faster you can grind them out to 230cc

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