DEEPSEA70

I'm hoping to use my stock 70 oil pressure gauge from the Ls sender. Has anyone swapped an LS and used the LS sender to the original gauge? Is there an adapter to replace the LS to the oil pressure tubing?

Thanks.

oldalaskaman

you may need to adapt your 70 o/p fitting to the LS block. most plumbing supplies would have the fitting/s you may need. home depot, lowes, also Earls

Garys 68

The ls ecu monitors a 5 volt reference signal through the oil pressure dender. The ecu then controls the gauge which is a stepper motor. No way that will work with any mechanical or old electric guage.
You can remove the ls sender and replace with a 16mm to 1/8" NPT adapter and use a mechanical gauge or an electronic sender for an electric.
http://www.speedwaymotors.com/LS-Ser...ter,20928.html

ignatz

DEEPSEA

There is an easy solution to your dilemma. You can either drill and tap into the fitting down by your oil filter or locate the fitting pictured from your GM parts guy.



You would probably like to know the part number. Well so would I. I looked through my receipts and didn't find it. You might try the LS1Tech forum. What I've pictured is a temporary setup for startup. I plan to run a line down in there eventually.

ignatz

A clarification. I use both locations. You can unscrew the original sender and screw in a brass fitting as recommended above, and as I did to "send" to the original gauge, with a new SS line. I will be using the pictured location to "send" to a low pressure switch to shut off the fuel pump if the engine oil pressure goes to zero for any reason. Worst case a crash with fuel spurting everywhere. I always liked that the mechanical pump stops pumping gas when the engine stops.

Garys 68

If you're using the LS ecu to turn on the fuel pump, the Hobbs switch for low oil pressure cutoff is unnecessary. The ecu shuts off the pump when it senses the engine has stopped (crank sensor?).
In addition, the ecu pressurizes the fuel system at startup, before cranking. You wont get that with the Hobbs switch.

ignatz

Gary: My LS3 is carburetted. No such sophistication! Don't know what DEEPSEA is using.

74modified

You could use your original sender - with an adapter
You can buy a brass adapter on flea bay or Nook & Tranny - ~$15.00
Here is the oil cooler by-pass and the original LS sender (with tap still in) both drilled and tapped for 1/8"npt. The original was cracked anyway, and not needed by the ECU.

DEEPSEA70

Thanks for the ideas. I'll look at all options. S and P also has a 16mm adaptor that might work as well. I may look into bypassing the oil cooler line. Room is tight to run the lines forward. I have the LS3 Dry sump in now and every step as been an adventure in fabrimodification. I want to keep as much an original look as possible. Obviously, an LS 3 dry sump in a 70 is far from original.