High capacity oil pump? - PeachParts Mercedes-Benz Forum

ConnClark · #1 03-02-2006, 02:11 PM

Is there a high capacity oil pump availible for the OM617 engine? I'm thinking about compound turbos....

boneheaddoctor · #2 03-02-2006, 03:15 PM

Quote:

Originally Posted by ConnClark

Is there a high capacity oil pump availible for the OM617 engine? I'm thinking about compound turbos....

don't have a clue , on the other hand I am curious about where you are going to get a better head gasket. I know exactly where you are going with this.

#3 03-02-2006, 05:45 PM

hey Conn,

Sorry that I never got around to replying to your PM...its been a very busy day/night for school stuff.

Here is the deal,

If you ran an external pump, you would either have to figure out a way to hook it up to the timing chain or live with the fact that it may fail sometime if belt driven (V-belts not such a good idea...would probably need dual row)

On a VW engine that some friends of mine built recently, the used the toothed timing belt to drive an external HUGE oil pump and also dry sumped the engine.

There isn't an "easy" connect to the engine unless you belted it or something like that.

I like the idea...just tricky figuring out where you could put the "larger" oil pump.

The tube that feeds the turbo on these engines moves a LOT of oil to them, even at idle. I BET if you used watercooled turbos with oil lubrication, you could cut down the flow to the turbos a little (they need less than oil cooled/lubricated ones) and probably make it a whole lot easier.

Of course water is a whole nother bag of beans but atlesat your engine would be happy.

Thats my thought...I'll be watching.

BTW the 617 seems to be able to handle 25psi+ of boost okay even in its "high mile" form...such as mine.

Wastegate hose blew off one night coming home...and coming off a stop sign or something I floored it. Woah nelly look at that boost. you could hear the engine sound totally different and the thing was screaming. And for the skeptics (like myself) the boost overprotection device was doing its job but when you have the fuel turned up and a modified compressor, it makes boost even with non-max fuel

I like my little modded turbo

RUinNC · #4 03-02-2006, 07:27 PM

There are many side effects to an increased oil volume.
Off the top of my head, I'm thinking....larger sump (pan) & larger drain jounals in the head & oil filter to keep up with the flow...pressure regulation...etc....etc

Diesel Giant · #5 03-02-2006, 08:34 PM

Hmmm... sounds like some block machine work is in your future on this project. Would be a neat set up if you can get it to work. How will you address the fueling reqirements?

OMEGAMAN · #6 03-02-2006, 09:10 PM

On the Porsche 930 (I have experience with 1) there is a scavenge pump from the oil return on the turbo. It is driven off of the left/driverside camshaft. I wonder if you could use one of these to lube an extra turbo maybe belt or electric drive.

#7 03-03-2006, 03:01 AM

Here is what you need.

http://cgi.ebay.com/ebaymotors/SCP-SBC-External-Drag-Racing-Oil-Pump-Stock-Car-Product_W0QQitemZ8042227544QQcategoryZ6778QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

imdavid28 · #8 03-03-2006, 03:33 AM

Quote:

Originally Posted by Brandon314159

BTW the 617 seems to be able to handle 25psi+ of boost okay even in its "high mile" form...such as mine.

Can you get 25 pounds by simply messing with the pressure sent to the wastegate? Does it help/hurt fuel consumption?

ConnClark · #9 03-03-2006, 01:16 PM

What I'm after is more than just more boost. I want boost over a larger range as well. Short of a VNT this seems to be the best option. I figure I can install a turbo with a smaller turbine housing as the first stage and set an external wastegate to something like 8 psi. I was thinking changing the compressor on my stock turbo like Brandon did to his and using that as a second stage and set its waste gate to 18 psi. The first turbo will spool fast and provide boost in the lower RPM range. As the first turbo falls off at the higher RPMs the second will take up its slack. Intercooling after each stage should boost efficiency more.

I got the idea from looking at my oxidizer cat and noticing that it was about the same size as a turbo.

boneheaddoctor · #10 03-03-2006, 01:21 PM

How about a PIC type microcontroller used to control vacuum switches based on measured boost to control a VNT type turbo without a computer?

ConnClark · #11 03-03-2006, 02:54 PM

Quote:

Originally Posted by boneheaddoctor

How about a PIC type microcontroller used to control vacuum switches based on measured boost to control a VNT type turbo without a computer?

That would work. The trick is measuring the boost. You will need two pressure switch sensors, one for an upper level and one for a lower level. The PIC would have to try and hold it in the range. When the low pressure switch is asserting its condition the PIC would have to close up the vanes to increase the gasses velocity in the turbine. When the high pressure switch is asserting its condition the PIC would have to open up the vanes to slow the gasses to the turbine. You might be able to do it with one sensor but the PIC would be hunting for the correct setting level all of the time

An FPGA would be better because you could take into account RPMS and map the boost accordingly.

boneheaddoctor · #12 03-03-2006, 03:09 PM

Quote:

Originally Posted by ConnClark

That would work. The trick is measuring the boost. You will need two pressure switch sensors, one for an upper level and one for a lower level. The PIC would have to try and hold it in the range. When the low pressure switch is asserting its condition the PIC would have to close up the vanes to increase the gasses velocity in the turbine. When the high pressure switch is asserting its condition the PIC would have to open up the vanes to slow the gasses to the turbine. You might be able to do it with one sensor but the PIC would be hunting for the correct setting level all of the time

An FPGA would be better because you could take into account RPMS and map the boost accordingly.

Or using a GM map sensor that is typically good to 5 bar....and use the hardware to convert that from Analog to digital for a more accurate and flexible reading. Its common for the Honda tuners to use the GM map sensors as the Honda ones won't work in a boost situation.

OMEGAMAN · #13 03-03-2006, 04:41 PM

EMD uses that exact same map sensor on their locomotives. Its funny looking at a 16 cyl 4400 hp engine with the same engine managment sensors as a GM car. I dont know for sure but I thing they get somewhere in the neighbourhood 30 psi boost

boneheaddoctor · #14 03-03-2006, 08:34 PM

Quote:

Originally Posted by OMEGAMAN

EMD uses that exact same map sensor on their locomotives. Its funny looking at a 16 cyl 4400 hp engine with the same engine managment sensors as a GM car. I dont know for sure but I thing they get somewhere in the neighbourhood 30 psi boost

30 psi is roughly 2 bar....the GM sensor is good for 5 bar which is more than it will ever see. good linear way to reference boost electronicly.