Lunati 30200741 idle vacuum

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VF69HARDTOP

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Hi guys
I'm looking to fit a Lunati 30200741 solid flat tappet cam in my 360 and wanted to know if any has one fitted and if it has sufficient idle vacuum for power brakes.

Solid Flat Tappet. High performance street/mild bracket cam with good mid range to high end torque and HP. Needs 3000 RPM stall converter, headers, 10.5:1+ compression, 3.73-3.90 gearing. Lopey idle. ;Advertised Duration (Int/Exh): 272/280 ;Duration @ .050 (Int/Exh): 243/251 ;Gross Valve Lift (Int/Exh): .546/.566 ;LSA/ICL: 110/106 ;Valve Lash (Int/Exh): .016/.016 ;RPM Range: 2600-6800

Thanks
 
I have not used one but I highly doubt that would pull enough vacuum for power brakes...

If it's an A-body you could just convert to manual brakes, these cars are light enough they really don't need power assist. My '70 Duster has always had manual front discs and I never felt the need for power brakes, I prefer the much better pedal feel and control.
 
MopaR&D said:
I have not used one but I highly doubt that would pull enough vacuum for power brakes...

If it's an A-body you could just convert to manual brakes, these cars are light enough they really don't need power assist. My '70 Duster has always had manual front discs and I never felt the need for power brakes, I prefer the much better pedal feel and control.
Click to expand...
Ditch the booster and enjoy the lopey idle and the easier access to the left side plugs
 
Listen to the the first two replies. My newest vehicle is a 98 Durango, and the two things I HATE about it are doors that lock themselves, and mushy power brakes. Best stopping cars I ever had were manual disc a bodies, even my wife liked them.
 
I have that exact same cam in my 426 lowdeck big block, and it makes 10" vacuum. Love the cam, very responsive, makes good power has good manors when driving.
 
I ran a booster on my 292/292/108 hydraulic; it worked fine.
If the booster is already on, try it, it cost's you nothing to find out. Stop worrying.

There are only two conditions that will affect it;
1) first start with no throttle blipping. As soon as you blip the throttle the vacuum will "go into" the booster and for as long as the check-valve holds and you are not pumping the pedal, you are all set.
2) sitting at a light for an extended period, in gear, with a leaky atmospheric valve or playing on the brake pedal; I suggest a line-loc/ hill-holder and the problem is solved. You know you wanted a line-loc right. Put two switches on it; a momentary for tricky business and a toggle for full-time on. Oh yeah, and a lil redLED to tell you it's on, so you don't look like a fool when the light turns green,lol.

EDIT;
the only caveat is that the dual-diaphragm is more sensitive to low vacuum. While the bigger singles are not.... in my experience. That 292* cam and dual-D did not play all that nice together; I swapped in a 15/16 M/C , but was still not happy. Next I swapped in a single from later Dart or F-body,(4-bolt so Ima thinking Dart) but don't remember which; and that together with the 15/16, did the trick.
I have a manual trans tho,and downshifting keeps the vacuum up, all the way to a stop. And on level ground, I don't need the brakes when stopped at a light...... So perhaps my answer is unfair to you if you have an automatic.... but you will figure out a work around.
And besides; a 15/16 M/C and a failed booster, requires similar leg power to a good booster and a 1.125 M/C, so if you can climb stairs you should still be OK.
 
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I used 73 c body brakes on my 68 polara with manual drum master cylinder - worked fine- no power
had to change the rear wheel cylinders (smaller) to minimize rear lock up
make it work
could have used an adjustable proportion valve if I had had to
 
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