Dry Sump Question

[Super_Dude]

Hey, I've picked up a second hand dry sump kit for a Gtr but wanted the opinion of some guys who already have dry sumps installed.

The seller told me ue was running a vacuum regulator off one of the valve cover breathers. It is a 4 stage peterson pump running all three pick ups to the sump and a head drain to the pan. He said if you dont have a regualtor it will pull too much vacuum and the pistons wont get any oil (rb30, no squirters) This seems odd to me and you wouldnt think it would matter.

So, is anyone running vacuum regulators? How much vacuum do you run? If you dont then what did you do with the valve cover breathers?

[BMYHOE]

from what i understand about my motor there has been no vacuum regulators installed, and have know idea about vacuum as the motor has not been started yet.

also what do you mean by vavle cover breathers?

[BMYHOE]

This is how i plumbed my dry sump set up, i am using a moroso stage 4

[bigmikespec]

I have seen the cam cover breathers just blocked off. It would make sense to run a regulator so you can set it to what you want.

BMYHOE are you using the Moroso dry sump tank and breather unit as well? It looks pretty compact.

[BMYHOE]

Bigmikespec- im using the peterson 3 gal tank & peterson breather tank.

hers some pics of the motor;

so mike why do people block the cam cover breathers for? i got dash 12 welded on my covers?

thanks

Dan.

[Beer Baron]

if you are scavaging from the covers it's probably not a bad idea to regulate the vacuum. they can suck pretty hard. hopefully a few others running dry sump RBs will chime in with their experience. but with it all set-up correctly blow-by will be practically zero.

[r33_racer]

4 stage pump wont pull enough vacuum to create any dramas with wrist pin lubrication. I would be suprised if you pulled more then 10in/Hg with a totally sealed motor. Typically need atleast 15+ to have any small end lubrication issues. Which usually requires 5, 6 stage or higher pumps to pull that amount.

Weve run ours with and without a regulator and its made no difference.

Best way to check how much is to hook up a vacuum gauge whilst on the dyno and read what it pulls.

[BMYHOE]

if you are scavaging from the covers it's probably not a bad idea to regulate the vacuum. they can suck pretty hard. hopefully a few others running dry sump RBs will chime in with their experience. but with it all set-up correctly blow-by will be practically zero.

so with no blowby does this mean a catch can is not needed? - i would still like to run the catch can cause i got everything to plumb it up. but if it will make more vaccum i obviously wont run it..

[Super_Dude]

No catch can with a dry sump.

My setup is scavanging 3x from the pan. I might just try running without a regulator and keep an eye on crankcase vacuum.

[Beer Baron]

r33 racer has given the answer. it's as simple as hooking up a vacuum gauge on the dyno and see what it's pulling from the head. and he's given some figures to go by.

and yeah no need for catch tank. the oil system is working properly and scavenging oil and vapour from the crankcase which comes out the 'breather' with the oil returning to the system.

[r33_racer]

You still run a breather can from your oil tank otherwise you may have some oil vapour spitting out of the breather line. If you do overfill the oil tank and system you will definitely get some oil spitting out that breather until it finds an equilibrium.

[Super_Dude]

Thanks a lot for the input. Do you have any tips for sealing up the motor better?

[BMYHOE]

Thanks a lot for the input. Do you have any tips for sealing up the motor better?

+1 thanks guys for the sharing this.

Also R33 is there a need for acummulators or is that not nessesary?

Dan

[T04GTR]

the whole point of a dry sump is to eliminate oil surge issues. so if plumbed up normally its a set and forget affair.

the only extra thing i would install is an electric gear pump plumbed into the oil feed so it cuts in if the belt breaks or for pre-oiling before start up.

[r33_racer]

You can run an accumulator if you want. It shouldnt be needed, but it does work well for pre oiling and incase something does go wrong you have some limited back up.

In terms of sealing the motor up, its just a matter of making sure any holes are bunged off and everything is siliconed up well with a good sealant.

The only other trick I would recommend is to get two machined discs to go either side of the pump pulley so the belt cant slip off. Also ensure there is something similiar on the crank drive side too. We lost a motor due to the belt coming off at the track when I ran off and some small twigs and stones got up and decided to lodge themselves between the pulley and belt.

[bigmikespec]

The only other trick I would recommend is to get two machined discs to go either side of the pump pulley so the belt cant slip off. Also ensure there is something similiar on the crank drive side too. We lost a motor due to the belt coming off at the track when I ran off and some small twigs and stones got up and decided to lodge themselves between the pulley and belt.

Do you ever use an "auto-shut down" or a limp mode when you get no oil pressure?

[r33_racer]

We have a limp home setup with the autronic if oil pressure isnt within certain parameters it will limit revs to idle only but no shut down. A shut down would be better as it might even save the motor if those conditions come about.

[BMYHOE]

ok good to know R33, will look into this accumulator set up if there is enough room

[Walk510]

at the moment i'm talking to dailey engineering about building dry sump pan system for rb30 RWD with the pump attached so there's only 3 lines coming off it scavange to tank pressure to pump and pressure to engine and the pan is billet have a look at the vq35 pans also had a chat to ati about building a balancer with a 60 minus 2 crank trigger in it too

http://www.daileyengineering.com/vq_35.htm

and the regulators you were talking about i believe the race v8's run as much vacuum as possible for more HP

http://www.petersonfluidsys.com/engine_breath.html

on my mate's 25/30 we run a 3 stage peterson pump and plumb the cam covers back to the tank with no restriction

in 3 years only problem we had was when the turbo died and we had no screens on the scavenge and the pump ate the ball bearings destroying the rotors $160 later and all fixed

[zebra]

^^ Thats the same style of sump the Nascar/Supercar guys run.

Much neater and simpler/reliable with less lines.