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Re-Rebuilding the 440-493 in a 1970 Charger

Not sure if this helps but my Hydro boost experience goes like this. Replaced the pump on my 3500HD. The swap was uneventful and a direct swap. I put new hoses on at the same time, majority of the fluid was out.
Filled the pump up with standard power steering fluid I had on the shelf. Went to test drive, brakes hardly had any assist, steering wheel would turn but choppy. Checked and the belt was tight.

I thought 100% I had a bad pump. I forget where on the web I ran across info that, if you use cheap fluid in a HB system, it causes issues like this. I drained as much as i could back out, got some Lucas PS fluid from the store, replaced the fluid, bled it out, sure as ****, it worked perfectly. Continued to work another 100,000 miles and 4 years later till truck was sold.
 
Thanks.
I was given no advice or suggestions as to the type of fluid to use. I used the fluid that was suggested for use when I swapped in the Borgeson steering box.

Borg 99.jpg
 
Greg, maybe with the front port getting going first was intended for the rear being drum since there was more slack to take up with the cylinders pushing the shoes out? Disc pistons don't pull back very much once the pressure is off. The inner seal on some, by design, help pull the piston back a smidge. I'm glad you are getting this stuff figured out but man, what a pisser for you.
 
The front brakes normally have light contact with the rotor at all times... Like ckessel mentioned rear drum brakes are pulled back by return springs.. Applying pressure to the rear brakes first allows the rear brakes to apply at virtually the same time as the front.. Also in a corner if the rears should apply slightly sooner it tends to pull the car straight but if the front applies first it can cause the rear to pitch out...
 
The front brakes normally have light contact with the rotor at all times... Like ckessel mentioned rear drum brakes are pulled back by return springs.. Applying pressure to the rear brakes first allows the rear brakes to apply at virtually the same time as the front.. Also in a corner if the rears should apply slightly sooner it tends to pull the car straight but if the front applies first it can cause the rear to pitch out...
I bench bled several master cylinders today. 3 cast iron and 4 aluminum ones.
The cast iron may have residual pressure valves in them. They all pushed fluid in equal time.
The aluminum ones though....two pushed equally, two pushed the front ports (Rear brakes) first.
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I think the brakes are right. Yes, I may have finally reached the point where they are as good as I can get them.
First up, I made new brake lines. I had brake lines formed to fit a power brake application before I started this project but they were cut apart so I could use the fittings on the first change, the 15/16" manual master cylinder setup that I installed on page 7, post #129 of this thread.

New brake lines in place, then I bled the system.
1 1/8" master cylinder.....was too big. Yes, I know....I thought it would give a shorter stroke but in doing so, the pedal effort was HUGE. It almost felt as if the power assist was barely working.
I swapped in the 15/16" unit that I previously had in manual mode.
This seems to be the best setup so far. Low speed braking is excellent. Higher speed braking is better than it was before I started all of this and it may get better as the pads bed in more.
I am not in awe of the brakes but they are better than ever. I was able to get the left front tire to skid. The right may have as well but I only had the left window down.
I don't recall ever skidding any tire on the road before. Burnouts...Sure, but no brake skids.

I'll continue to monitor the feel of the brakes while I drive the car.
The engine runs great. Idle quality is better than I expected for the cam I'm using.
I have a standard volume oil pump and the pressure shows that. In the past I've had cold pressures around 70 which drop to 30 at low speeds. Cold pressure is around 50 now, warm pressure while rolling on at 40-50 mph around 2000 rpms is 40. I never liked the 10 lbs per 1000 rpm minimum with Mopar engines. I'm at double that but seeing a lower number is an eye opener since I'm used to seeing the higher ones. The current pressures should be more than adequate.
The transmission needs an oil change but the clutch and transmission feel great. Shifts are as smooth as when I installed the kit early last year.
I keep forgetting to tighten the lower control arm shaft nuts!
I'll see about getting a front end alignment next week.
The engine bay and exterior of the car need a good cleaning. P/S pump leak (fixed), Rear main leak, (fixed) Brake fluid leaks and spills (DOT-5 so no risk to paint...fixed)
@beanhead sent me an FBO ignition module and Flamethrower coil to put in.
After that.....I am not sure.
Maybe put some miles on the car and tire marks on the road?

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I know that some other members here have suggested it but just tonight, Dr Diff sent me an email with a link to a site with suggestions on "bedding in" new rotors and pads.
My rotors are "zinc coated" so this applies:

When following these instructions, avoid other vehicles. Bedding is best done when traffic is light, as other drivers will have no idea what you are up to and may respond in a variety of ways ranging from fear to curiosity to aggression. A police officer will probably not sympathize when you try to explain why you were driving erratically! Zeckhausen Racing does not endorse speeding on public roads and takes no responsibility for injuries or tickets you may receive while following these instructions. Use common sense!​

  1. From 60mph, gently apply the brakes a couple times to bring them up to operating temperature. This prevents you from thermally shocking the rotors and pads in the next steps.​
  2. Make eight to ten near-stops from 60mph to about 20 mph. Do it HARD by pressing the brakes firmly, but do not lock the wheels or engage ABS. At the end of each slowdown, immediately accelerate back to 60mph, then apply the brakes again. DO NOT COME TO A COMPLETE STOP! If you stop completely, with your foot on the brake pedal, pad material will be imprinted onto the hot rotors, which could lead to vibration and uneven braking.​
  3. The brakes may begin to fade after the 7th or 8th near-stop. This fade will stabilize, but not completely go away until the brakes have fully cooled. A strong smell from the brakes, and even some smoke, is normal.​
  4. After the last near-stop, accelerate back up to speed and cruise for a few minutes, using the brakes as little as possible to allow them to cool down. Try not to become trapped in traffic or come to a complete stop while the brakes are still hot.​
 
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This is exactly how I bedded in my pads except I slowed to about 5 mph, but then back up to 60 mph with no cooling in between. After about 8 stops the Brembos were definitely getting hot and I could smell the brakes for awhile afterwards.
And yes, find a quiet road. It was a Sunday afternoon when I did mine and a reasonably quiet dual carriageway, but there was a car a few hundred yards behind me that didn't know what was going on. They went to overtake and then I sped up again...and then braked and then sped up...in the end they just hung back until I finished. I waved out the window while I was doing it to let them know I wasn't a psycho...
 
This is weird. I have never done this in all of my years.
I have well over 1,000,000 miles driven since 1982 when I got my license.
Have I been leaving "performance on the table" all this time?
 
Potentially...but if you're not a heavy braker then you probably won't notice.
Some people are very heavy on the brakes on the street. Personally, I'm a very light braker and prefer to anticipate the road ahead and drive smoothly.
You can get more squeeling if they aren't bedded in properly but that has a lot to do with pad material as well.
 
I know the hydro boost system in my 95 3500 truck with rear drums won't apply good pressure to the fronts if the rears are loose!The whole system has to work together or it's like stepping on a baked potato!
 
Whatever you do, don't attribute your success to her suggestion. You'll never live it down.
My cousin gets aggravated with his wife because no matter what he is doing, she asks "why are you doing it that way?"
 
Hey, Greg. I was at a cruise-in in September and looked at a Road Runner with a hydro-boost. Owner said he was thrilled with it. He didn’t seem like the type that did his own work, I’m sorry I didn’t talk with him further.
 
Dude, you're so fast I can't keep up!
Remind me - final install - is this 4 wheel disc or Front Disc/Rear Drum?
I'm surprised with the 1-1/8" MC and the Vac Pump that it was such a hard pedal.
 
To recap:
Fronts are the 13" Cobra rotors with twin 1.59" piston calipers, rears are 11.7" with single 1.50" piston calipers, 15/16" master cylinder with 1975 Dart power booster, Cadillac vacuum pump. Brake pedal pushrod hole moved UP 3/8" but with the reduction linkage in the booster, it has less effect than it would in a manual application.

Awhile back, I was totaling up the costs of this project and was surprised that it didn't add up to more. The Tremec swap last year went over $7000 including some tools that I bought to make it all happen. So far, I am around $5000 with this including the brakes. I intend to compile a list to make it as close to accurate as possible. This includes dead ends like hydraulic fluid and hoses for the hydroboost effort, power steering pumps, etc.
This project included a short block rebuild. The heads were gone through a few years back and checked out fine this time. The front suspension was cleaned up but didn't need bushings or ball joints. I did install new tie rod ends and sleeves. The brake kits went a bit close to $1400. I reused some good parts to save money including the cam and lifters, (saved and stored from my previous engine combination in 2014) The vacuum pump, power booster and various bits of hardware.
I'll state again....The car feels smoother than I recall from when I ran this cam before. I was a bit apprehensive about using the cam for the way the car felt with it. An idea occurred to me. This time, because of the heavier pistons, I had the rotating assembly balanced again. Maybe this balance job was better than it was with the Ross pistons I had before? Seriously....it feels like I added sound deadener to a car that previously had just carpet on the floors. Power is great. Even 1/2 throttle in second gear gets the back end creeping sideways. This is fun when you expect it and unnerving when you don't. I expected this combination to be faster than the car has been before and I may be right. I've never drag raced it much to know what it really could do. I did have it on a chassis dyno in 2005 or 2006 with a combination a bit different than it has now. It registered 369 HP to the wheels then with 10.8 compression, the MP '509 cam, stock Edelbrock heads, 2" headers and a 727 with a slippy 3000 stall converter.

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KD, nice work and thanks for the re-cap so I didn't have to go back and re-read 797 posts:)

Thanks also for that aluminum MC link. I'm going to look into that (I wonder if there's a reason they didn't make an aluminum offering before?)

The motor re-balance is a good point. I'm glad the motor feels smoother than before and you got it all fixed and sorted just before the holidays! Remember also, back then you were running the Auto trans. In my experience as a manual trans enthusiast, a manual trans makes everything better, allowing the motor to sit in the RPM sweet spot with better transitions. Even if it's not faster in a straight line, most manual trans always feel better to drive when speeding up and slowing down and then when you go back to the auto trans it feels like there's a headwind in front of you holding you back until you really put your foot in it. Low to mid throttle feels crisper (vs auto trans for the same car/engine).

Sounds like after I get a few things completed on my car, we may be in for an Infinion Raceway 1/4 mile matchup next spring.
 
Today I had planned on bedding in the pads and rotors.
AS I left the house and made it down the road, the Voltmeter was reading in the 15+ range. I've seen this before when I've drained the battery a bit by working on stuff with the doors open, dome lights on, etc. I drove a bit, maybe 10 minutes and it stayed there. I turned on the headlights to create a little load to see if the gauge would drop. It did at idle but it worried me enough to think that maybe I needed another voltage regulator. I picked through my stash and tried another...and the car wouldn't start. I tried another and still, no spark. I put the original black one back in and it fired right up. I'm confused as to how a voltage regulator can cause this.


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I did find another VR that allowed the car to start but it was getting the same readings. I used my multi-meter and was met with similar numbers at the battery when it was running. After a few minutes, the numbers came down into the 14 range.
I did go out and start bedding the pads but the car kept wanting to stall on hard acceleration. I started a thread about this a short time back...

It wants to stall upon fast braking and on downhill slopes...

I will have to look for the cause with all this free time that I have now.

I didn't fully bed in the brakes because I'm also a bit curious about the oil pressure.
This is the first time I have used a standard volume oil pump in a big block. I read that most street engines do not need the higher output that the HV pumps provide and that the HV just wastes HP.
I'm running Driven oil....

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The oil level is full, the oil is clean. I'm getting around 20-25 lbs at hot idle. During cold start, it is around 50 lbs. Once it is hot, even slowly running up to 5500, the oil pressure stops climbing and stays around 45-48 lbs.
Before the rebuild, it would run close to 75 lbs at cold fast idle.
It does rise with rpm but not as fast as before when I ran the HV pump and this oil:

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I have a NAPA or WIX 1515 filter. It isn't some POS but could it be responsible for the lower numbers due to some restriction?
My old crappy 75 Power Wagon 440 runs a cold # over 60 with a hot idle around 30-35.
I recall having well over 40 lbs going down the road in this engine before with the thinner oil but the high volume pump. Now it is around 30-35 @ 2000 rpms. Maybe I am worrying for nothing but it has me curious.
My bearing tolerances were on the tight side. Each rod was .0015 and I had between .0015 and .002 on the mains. There are no leaks. It does not clatter other than the clickety clack of the solid lifters and even that is a bunch quieter than it was with the MP '528 cam with the wide lash that cam calls for.
I'm thinking of swapping in another filter of another brand.

I swapped in the FBO ignition box today:

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This required bridging the terminals and bypassing the ballast resistor so I did and taped them up.

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Flamethrower coil.....

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It seemed to start easier. It idles the same. I set timing but didn't drive it. I'm concerned about the oil pressure.
I used this pump....
Melling M-63HP Melling Performance Oil Pumps | Summit Racing


mel-m63hp_rn_ml.jpg

Melling Performance Oil Pumps M-63HP

Oil Pump, Standard-Volume, Chrysler, Big Block, B/RB, Each
Part Number: MEL-M63HP
4.0 out of 5 stars ( 1 )
In Stock (more than 10 available)

Estimated Ship Date: Today
$118.08




Oddly, the high volume one from Melling is actually cheaper!

mel-m63hv_nm_ml.jpg

Melling High-Volume Oil Pumps M63HV

Oil Pump, High-Volume, Standard Pressure, Chrysler, Big Block, B/RB, Each
Part Number: MEL-M63HV
4.67 out of 5 stars ( 15 )
In Stock (more than 10 available)

Estimated Ship Date: Today
$105.80

Did I pick a bad brand? There are others listed for well over $200.
 
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