Vacuum pump for power brakes

I plan to run a 455 with around 7" of vacuum, which is not enough for power brakes. Diesel powered cars run vacuum pumps for the brakes. Can I use the same setup?

Royden

 

Yes Royden,

The ones found on cars with the late 70's/early 80's Oldsmobile diesel engines bolt right in.

 

Actually, the diesel cars did not use a vacuum pump , but a hydraulic boost using the power steering pump. It is a direct bolt in the 80's regals, cutlass and similar GM bodies, but takes modification to fit the earlier GM a-bodies. You will need to cut another hole in the firewall and modify the pedal assembly. You may even want to use part of the pedal assembly from the donor car. Use a new master cylinder for the donor car, and your current proportining valve. This will work even if you have drum brakes in the front while the donor cars used disc brakes in the front. Be prepared for about 40 extra pounds and the ability to stop on a dime with a big lopy cam.

Cheryl

 

I have a booster and master cylinder out of an Isuzu 3ton truck with 300mm rotors on front and drums on rear. Do I hook up the vacuum line from the booster directly to the pump? My booster/cylinder ass. sits up under the front cowl above the steering column. Its a 1928 car so I have a lot of room under the cowl.

Royden

 

You might need a vacuum canister. I used a pump from a Volvo diesel and after pumping the pedal 3 times it got hard.
Also be careful about rpm's I would think most stock pumps can't take more than 6-7000 rpm @ the pump

 

Electric pump.

I have an electric vaccum pump that I can send you a pic of if you would be interested in using it. I believe it was made by Powermaster.

It will provide the needed vaccum to run the brakes. That is what I used it for with too big of a cam.

 

Yes pls Jimmy, if you could send a pic.

Royden

 

I just got back from the beach and will get you a pic. tomorrow.

I need to send y'all a picture of the shark that my 6 year old caught. We had a blast.

 

I just changed the vacuum pump on my Powerstroke diesel today. A buddy of mine that runs the body shop at a Buick dealer in the city told me that it's the same exact pump run on '81 Cutlass w/Olds 307. He said that when in O/D, the 307 couldn't produce enough vacuum so it needed a pump. It's small and looks like a tiny p/s pump. It pulls 21" of vacuum.

 

pics.

It is made by powermaster. I will pm you the details.

 

Thanks for your input guys. Reynold, that I would probably prefer as I will not be running a belt driven water pump(electric) so I will have the room. 21" would be awesome. Where could I get one from?
Jimmy, what vacuum does it produce?

Royden

 

Royden, it came on '81 Olds Cutlass with a 307ci. I think several GM cars used it though. Mine is on a Ford F350 Diesel, but it has a serpentine belt pulley on it. It has a tube for 11/32 vacuum line connection which is the same size as the check valve on the booster. Do an online search for vacuum pumps for Ford diesels. My '91 F350 had the same pump but V belt pulley. I think my '94 had serpentine so check the earlier models.

 

I am not sure of the inches of vaccum but I will hook it up to a battery and a vaccum gauge this afternoon.

 

Here's the pump off my truck.

 

Here's the back

 

I checked the vaccum pump and it cuts on at 17" and cuts out at 24". It also have exacellant volume.

I'll send you a PM with more details.

 

http://victorylibrary.com/mopar/pump-tech-c.htm