426 Street Hemi stock camshaft

Richard Cranium

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The cam in my 66 Belvedere is the infamous "3/4 race cam", whatever that is. Being an automatic, the idle is about 1,200 & when you drop it in gear, it drops down to about 600 & barely wants to run. Not to mention that it produces no vacuum at 600 rpm for the power brakes. So. my intention is to get a stock street Hemi camshaft & it appears that this one is the only one available. It has the same lift as a stock cam, but the duration is down from the stock 278 to 241. Thoughts?

https://www.summitracing.com/parts/dcc-p4529316ae/make/dodge#overview
 

ruffcut

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That's a pretty tame cam. Should be very streetable. I'm wondering what's in there now? Back in the day, I remember the term "3/4 race" I believe there was a full race also? ruffcut
 

Runcharger

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I've run it. Nothing deballs a Hemi like running a camshaft like that. It will do what you want though.
 

69 GeeTeeX

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Call comp cams and have them do a custom grind to match what your looking for. Doesn’t cost much more than the one you’re looking at Summit. That’s what I did on the last stock Hemi I built. Received the cam in 3-4 weeks.

If the cam was changed does it still have the stock torque converter?
 
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toolmanmike

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That's 241° @ .050. Advertised is 300 or better I bet. No wonder why it's such a pig and 106° is going to be choppy.
 

Richard Cranium

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Nobody’s got the stock cam. They are all on back order and this is the only one available that I can find.
 

Hemirunner

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The cam in my 66 Belvedere is the infamous "3/4 race cam", whatever that is. Being an automatic, the idle is about 1,200 & when you drop it in gear, it drops down to about 600 & barely wants to run. Not to mention that it produces no vacuum at 600 rpm for the power brakes. So. my intention is to get a stock street Hemi camshaft & it appears that this one is the only one available. It has the same lift as a stock cam, but the duration is down from the stock 278 to 241. Thoughts?

https://www.summitracing.com/parts/dcc-p4529316ae/make/dodge#overview
The 241 duration given is at .050 lift. The 278 figure quoted is most likely a seat to seat duration. It’s like comparing apples with oranges. I would think 241@050 is larger than a stock hemi cam.
 

Hemirunner

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From an old post on here, stock hemi was 226@050 and a 112LSA. Seems reasonable.
 

w.Hudson

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I used Cam Motion in Baton Rouge, La. They grind camshaft for Ray Barton and are a bunch really sharp guys.

They cut a cam for my Hemi - solid lifter .541 on the intake .573 on the exhaust 252 duration @ .050 110 Centerline.
The car had big headers and 3 inch exhaust. Auto transmission
and the stock Hemi Street converter. I set the base ignition timing at 16 degrees and 34 total.
It idled very well and sounded great.
Cam Motion also cut a cam for another Hemi with exhaust manifolds and a 4 speed. It had more lift that the other cam and it
ran just as good or better.

Neither one of these two cars had power brakes. Make sure to tell them that.

I bet they can grind you something that will out perform the stock cam but be very docile.
 

Cliff Ramsdell

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Well, what about a looser converter? The job to swap either a cam or a converter is probably a bit quicker to swap the converter. If you like the way the car drives other than the low idle that could be an idea.

Just a thought.

Cliff Ramsdell
 

AR67GTX

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I think the stock cam had an advertised duration of around 284, .474 lift and later at .484. But not sure about rated lobe separation - what I found mentioned was around 110. Sounds like 106 would hurt idle vacuum that you’re interested in.
 

F4R/T

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Reach out to Mr Six Pack and get one of his cams... or at least check him out. Tom Hoover was a very good friend/ neighbor of his...
 

diesel_lv

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While you have the cam you currently have, check your timing. 16° advance can make a huge difference on idle in gear. May increase vacuum also.
 

Runcharger

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I've also run that Comp cams 270-S8, also very mild but it performed better than the first one listed. I think you would be happier with that one.
 

Nate S

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Classic Industries claims to have the hydraulic version in stock.
 

INTMD8

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Agreed on possibly bumping up initial timing (then limit total of course) and loosen the converter.
 

Jerry Hall

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781317-57551771862402dd01f447429fc1e7ca.jpg

They did exist. Ofcourse I'm not much help in your search.
 
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