440 camshaft

[Don Frelier]

I have a .484 in my 383 with power brakes, no issues.
It idles pretty well too.

 

[diesel_lv]

I'm running 0.541/0.537 lift 230/236° duration at 0.050 on my 496, w 16° base timing, I idle at 850 in gear at 14" vacuum.

 

[4mulas]

Comp 21-305-4.
2000 miles since rebuild. Great so far.

Sure! This one would be just fine

 

[451Mopar]

It does sound like there are other issues with the vacuum being that low?
What year type power brakes? Drum or disk?
My '71 Charger Power Disc brakes seem to work fine with 12"+ vacuum.
Just using a vacuum resvoir/can with a check valve.
A few blips of the throttle builds up the vacuum after startup.
The engine has very low vacuum, maybe 4-5" at idle, 270+ duration @ 0.050" cam, 0.726" lift

 

[Wietse]

Seems there are more mystery cams around that seem to pull less vacuum than expected.
I am running an "oldie" Hughes engines 3844BL cam (238/244* @ .050") that only pulls about 7" vacuum at idle of 850 rpm.
Believe me, i've tried everything to ensure i have no vacuum leak, it does the same with the old carbs i used and with the current Holly Sniper EFI.
My power brakes do work, although during idle there is some more effort required to brake but it is managable.

My future plan is to swap to a 2832BL cam to get a little more vacuum and better drivability.

 

[lewtot184]

from my experience the comp 21-305-4 was pretty miserable in my 440. the mopar 272-.455 went 3mph faster in the 1/4 mile than the 21-305-4. i have no experience with the crower 271. the summit 6401 has good mid-range and reasonable vacuum at a low cost. i liked that summit cam using cast manifolds. but, i'd look at at a comp xs268.

 

[junkpile]

idle quality is fine, I did fix a vacuum leak at the carb base a few months ago. At idle in gear I am at 900 rpm, any lower and the thing just does not behave well in traffic and in Atlanta its all traffic. Base timing is 12 degrees in at at total of 37. The car seems to like it right there and will run on pump gas if i need to. All in all it runs fantastic, I just want to have vacuum for the brakes without the aftermarket pump. So I will have to look into a cam that will give street performance with a minimum lobe seperation of 110-115 in order to get 20" vacuum back out of the motor for the brakes. I hope that is correct.

thanks for the advice, any cam suggestions will be looked at and I now have a few to call on.

 

[junkpile]

Since that is not a "big" cam, can't see how that's the low vacuum problem. Better look for other issues.

No leaks, everything checked. I have 7" vacuum at idle in gear. I tested with a vacuum gauge at the intake manifold connection point. that is with 12 degree base timing 37 total.

 

[66Satellite47]

No leaks, everything checked. I have 7" vacuum at idle in gear. I tested with a vacuum gauge at the intake manifold connection point. that is with 12 degree base timing 37 total.

Well good luck, no advice from me.

 

[strokie]

You just said you liked it way better when it was stock, I think the solution for you is a stock magnum camshaft ?

Or better mr 6 pack cam..

 

[1STMP]

You could switch to hydroboost and keep your
existing cam.
https://www.powerbrakeservice.net/n...lymouth-charger-hydroboost-brake-booster.html.

 

[440 Charger]

Hey guys, looking for some advice/info. have a 440 that I have been running for years with a 484/284 cam. I love the performance but hate some other things. Looking to replace it with a cam that will retain engine vacuum for power brakes but still have some performance above stock. are there any recommendations.

history: I have worked hard to get the timing and carb set for this cam, i can drive it anywhere without issue. I recently installed a Leed vacuum pump to compensate for the power brakes. The system works great but at night with the headlights on the electrical system is always charging whenever the brakes are applied due to pump power draw. I liked this motor much better when it was stock, it was fast and fun to drive and had no external issure, now its just a pain in the butt. I am running a 2800 stall converter, 737 with 3:23 rear gears. the motor is .030 over. What is a good cam number like used in a 440HP motor that I can install to gain back my vacuum accessories off the motor and put this car more back to how its supposed to be without all the modifications.

thanks in advance.

That will be interesting for you.

 

[Curiousyellow71]

The 484 mopar cam is available w 108 lsa(probably what you have) and 114...big difference in the two. It also matters what static compression your engine has, the more compression, the more vacuum. A narrow lsa like 108 less vacuum and a rougher idle. When guys say their car runs vacuum brakes with a particular cam that doesn't translate well unless yours is built identical.

 

[forphorty]

I would imagine that shortening the mech advance in the dist so that you can run about 20 initial might help quite a bit.

 

[oldkimmer]

451mopar thank you.
o.k. let me clarify something. the wiring is all new with electronic ignition. I was and am still running a vacuum resvoir/can with a check valve and guage. the engine will only make 8" of vacuum at idle in gear off the manifold. The can will hold 21" of vacuum but after a few pumps of the pedal in traffic its vacuum is so low i have a hard pedal and no feel with the brakes. The can will hold the 21" vacuum without bleeding out even after walking away for an hour. I installed a Leed "bandit" pump that now makes 25" vacuum, still no leaks and great breaks every time in need them. Im pulling the power source from the battery thru a keyed on relay to operate the pump. they system works very well the pump kicks on when the vacuum get below 17" and within seconds i have 25" again. its just at night with the headlights and the brakes the amp meter is always running high in the charge range until the pump gets to 25" vacuum and shuts off. I would like to put the system back to more of a stock set up running off the manifold vacuum to the can then to the booster. In order to do this I need to change the camshaft to gain vacuum. This should make the car more street friendly, tax the electrical system less.

I had a similar problem years ago. I bought a good battery and all the symptoms went away. I couldn’t believe that’s what fixed my problems. I had changed the voltage regulator the summer b4. It never helped at all. Kim