CB 2 stage oil pump mods

[3literboy]

Well I pulled out the CB 2 stage pump and installed a melling. The melling put out 80 psi cold and 35 to 50 at idle hot. When the oil temp reached over 180, the oil pressure stayed above 25 psi at 1000 rpm. This pretty much eliminates bearing wear tec.

I then detailed the CB pump. I added a 5/8 ID oil supply hose and tapped the pump inlet for 1/2 NPT. I also opened the supply side up to the gears. I then zero decked the pump gears, and opened up all passages and return galleys.

I then pulled the melling 32mm, and reinstalled the CB pump. I may have netted about a 5psi at hot idle. The CB pump will not work for this application, as far as, I am concerned. So, it will be a Bugpack 2 stage dry sump set up. I will tap the case for external devices for later, but I think I will use the stock oil filter setup and internal regulator. I will just bypass the case galley at the pump housing, tap it and plug it, and run the pressure side from the pump outlet to a external galley location.

[Piledriver]

...I then detailed the CB pump. I added a 5/8 ID oil supply hose and tapped the pump inlet for 1/2 NPT. I also opened the supply side up to the gears. I then zero decked the pump gears, and opened up all passages and return galleys.

How'd the modded CB do at higher revs?

I wouldn't expect too much better at idle, its a 21mm pressure stage, and there is no seal to the scavenge stage, other than the gears and shaft clearances.
The trick of any DS setup is the oil has a lot less air in it, so as long as you read SOMETHING at idle, it's probably fine.

Wetsump at high revs, you have mousse faster than you can blink.

I ran the outlet of the pressure stage out a full flow cover and plugged the passage to the case... Much easier.

Glad to hear the Melling worked for you.

[3literboy]

Ok, I ordered a Bugpack 2 stage pump from Doghouse and have it in my hands. 3 sets of 30mm gears with the stock scavange location. I also oredered a Jaycee oil pressure and filter system and exhaust mount. next a set of Empu racing stacks, and a cam from DRD. I am pulling the motor and pulling it apart. I need to tap the case for the external regulator.

I saw a pic of the oil pressure line going to the inside oil filter boss. I f I tap there, will the oil back flow to the stock regulator, or will it be completely bypassed?

Also, i am ordering a .060 copper shim and cutting .060 off the heads. The cam is a DRD 328 advertised 286 effective at .050 with .419 lift. I should have 14 to 1 compression and at least get into the 10s. I am thinking of either EPC 51.5s or have Jaycee do my throttle bores.

[Piledriver]

IIRC Jaycee sells an insert/feeder that bypasses the stock setup.

The stock bypass is easy to plug off anyway if the case it apart.
(plug the return hole at the base via the external plug hole with a setscrew and some green locktite)