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Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Sun Mar 05, 2017 2:36 am
by Bruce.m
Not getting your plan. I'm Confused.

You want to use the tank like a large pot of oil in the middle of the pressure line?
In that case, the oil must be at full pressure or the bearings will be getting low or zero pressure.
So the oil tank must be 100% sealed or it will fill to the top and leak away oil / oil pressure from any opening.
Because the oil in the tank is under pressure, any gas or bubbles will be compressed and remain in suspension (like a sealed bottle of coke).
The oil will have to be de-gassed in the sump as a wet sump (which it has to be or the pressure pump will be sucking in air).

I thought you were maybe trying to have a sort of remote deep sump but that's not the case (deep dump isn't pressurised).

Just can't get my head around what you are looking to do.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Sun Mar 05, 2017 2:43 am
by Bruce.m
Also.., why is the 2 stage pump not a proper dry sump?

Yes, the oil is still collected in the sump as it is sprayed around the crankcase and drains to the bottom but the scavenge stage is hoovering up as much as it can to keep the case oil level very low. The oil is then stored in the oil tank at ~zero pressure allowing it to de-gas (the scavenging stage draws foamy oil).

This is exactly the same as the 911 system.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Tue Mar 07, 2017 6:37 pm
by Matt Mariani
Thanks you two ^^ you're 100% correct. I do have to use the CB pump otherwise no degassing in the tank will take place. This came to me as well.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Wed Mar 08, 2017 11:26 am
by Bigbee87
I've ran the cb dry dump pump on my dune buggy with 1968cc turbo and it has operated excellent. 7 quarts total of straight 30w. Doghouse shroud and front oil cooler with thermostat. Temperature stays constant and fixed all my oil overheating issues that I fought for a couple years until doing it right!

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Fri Mar 10, 2017 12:46 am
by Passatman
Does anyone see a problem if the tank is placed at the front of the car. I have a dive tank that i want to convert to a dry sump tank.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Fri Mar 10, 2017 2:49 am
by Piledriver
It's been done, and you do realize that aluminum air tank is about an inch thick, right?

...Does make installing fittings easier... and rocks or a tossed axle wont really hurt it.

I would keep it as close to the pressure stage inlet as physically possible, with a short, fat hose.

Hmmm... Its round, and machinable... can make a flat lid... baffles etc.
Not a bad plan under the luggage tray on the R side just ahead of #1.

I know where one is... :twisted:

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Sat Mar 11, 2017 12:16 pm
by Matt Mariani
My existing layout will work well bipassing the sump tank.

But.. it occured to me i could use an electric self priming oil pump designed for continuous use right after the sump tank. This would prime before start up (and after oil changes) as well. I think i actually prefer this to the CB setup now.

They can make better pressure than the mechanical VW oil pump and as said I could prime before start up. Pressure varies with engine speed. I'll always be watching oil pressure anyway..probably install a big warning light in the old clock location on dash facia.

heres the pump: https://www.summitracing.com/parts/til-40-527

Here's a couple customer reviews: "I purchased this pump to prime my big-block's dry-sump oil system before each start-up. This pump works a treat and does the job quickly via a "momentary" switch I use inside the cabin. I get 40psi in about 5 seconds. It's quieter than I expected which is a bonus too. The only downside I can think of is that it's reasonably heavy"

Here's a review of a smaller one:
"I bought this exact pump about six years ago for my remote mounted turbo. I use it to return my oil from the turbo back to the engine. It handles heat well and has proven its self to me. It is still going strong and the truck gets driven over an hour every day. Very happy would definitely recommend."

Me again:-) :
this way no fiddling with modding the CB pump and or mounts. This could work well if dialed in right and with a bigger tank probaly a better set up pressure wise than the CB pump. Less HP draw too (a little anyway)

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Sat Mar 11, 2017 3:12 pm
by Piledriver
We have discussed using a similar pump as a scavenge pump before start-up in case the engine sits awhile and fills up with oil, or as an alternative to an Accusump. Its still not a dry sump system by itself, they can't move oil fast enough.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Sun Mar 12, 2017 4:06 am
by Matt Mariani
I'm thinking on the pressure side and less than a few feet away from my pressure inlet and directly between it and my ds tank. If it moved oil a little slower than the stock oil pump but makes 40-60 psi that would be about right to keep the amount of oil in the engine sump low, like the CB pump.
Now this layout, I see no difference..
I looked at the internal oil passages on the CB pump and they are too small imo. I also bought an oil cooler adapter plate from CB before I made my own seen in the pic. I returned it as I saw no use for it. The oil passages were tiny and because of their complicated path looked very restrictive.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Sun Mar 12, 2017 4:30 am
by Piledriver
Matt Mariani wrote: Sun Mar 12, 2017 4:06 am I looked at the internal oil passages on the CB pump and they are too small imo. I also bought an oil cooler adapter plate from CB before I made my own seen in the pic. I returned it as I saw no use for it. The oil passages were tiny and because of their complicated path looked very restrictive.
That's why I did the flow path modifications, the resulting passages are not restrictive, and are in the right place for a type4./
Good luck with whatever you do.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Sun Mar 12, 2017 2:46 pm
by Matt Mariani
Thanks Piledriver for all your help

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Sun Mar 12, 2017 4:17 pm
by Piledriver
Consider the size of the passages in the block, none are larger than 9mm, most are much smaller.
The multiple 90 degree bends are more of a flow issue than the passage size.

On your electric pump---the ability to make "40 PSI" while pre-oiling has little relation to actual flow capacity.
If you measure the gears I suspect they are nowhere near 21mm or 26mm, and the RPM is ~fixed, so its use is quite limited to either pre-oiling, scavenging a turbo, or pre-scavenging excess oil out of a sump to the tank after long periods of being parked, if the tank is mounted too high and fills the engine with oil.

Its good for those uses, or an oil pump on the transmission as Porsche did on race versions.

I'm really just trying to encourage you to use a proven setup, think of the poor bearings...

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Mon Mar 13, 2017 7:29 am
by Matt Mariani
The electric pump doesn't have the flow rate at 1-2 GPM. I like the idea of priming before start up either way though.

Here is the flow rate of a VW 26MM pump (Ken) :

It can be figured out using this formula:
MA is the major dia. of the pump gear
MIN is the minor dia. of the pump gear (dia. between the stars)
GW is gear width.
GPM is gallons per minute

MA=__________ divided by 2 =________squared x 3.14 = (Y)
MIN=__________divided by 2 =________squared x 3.14 =(Z)
(Y)________ - (Z)_______= __________ (X)
(X)_____ x (GW)______=_______(A) Area cu. in.
(A)_____ x _______RPM = _______ divided by 231 =_______GPM
GPM_______ x .85 = _________ GPM Actual Flow.

This is what a Schadek 26mm pump should put out at 4000 rpm's. All measurement are in inches.
Remember the pump turns at half of the engine rpm's
MA 1.29
Min 0.793
GW 1.025

MA= 1.29 divided by 2 = 0.645 x 0.645 x 3.14 = 1.306 (Y)
MIN= 0.793 divided by 2 = 0.3965 x 0.3965 x 3.14 = 0.494 (Z)
(Y) 1.306 - (Z) 0.494= 0.812 (X)
(X) 0.812 x (GW) 1.025 = 0.832 (A) Area cu. in.
(A) 0.832 x 2000 RPM = 1664 divided by 231 = 7.203 GPM,
The pump would put out 7.203 gpm if it was 100 percent efficient but, most pump are only about 85 percent efficient.
GPM 7.203 x .85 = 6.122 GPM Actual Flow.
So a engine running at 4000 rpm's should put out about 6.1 gpm if it had a Schadek 26mm oil pump.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Mon May 08, 2017 6:55 pm
by Matt Mariani
The motor runs great guys.

Re: CB PERFORMANCE DRY SUMP PUMP.

Posted: Mon May 08, 2017 9:37 pm
by Piledriver
What did you end up doing?
And pictures, we all love more pictures...