screaminchicken had told me a great way to make the 3rd gen oil pressure sensor work on an LSX swap by getting a block plug and having a shop drill out a hole in it and thread it to match the threads on a 3rd gen sensor. Does anyone have a part number for a block plug that would fit in the hole on a Gen III block? I'm wanting to have a shop thread the hole for me, and I just picked up a 3rd gen sensor today, so I'm looking to get this done soon. Any help would be greatly appreciated.

look for M16X1.5. u wont find it in a autoparts store. try ibt i send you.

if ur going to have a shop do it get the biggest block plug u can find. and drill and tap the inside and tap the outside....might cost u a little bit more.

if u have the lsx oil psi sending unit......ask the shop if they can work with that after cutting the plastic housing off

if not this is a hit and miss....at orilleys look for the company called equiis they have a bag of sending unit adapters in a bag. one of them in 3/8 npt F to M16X1.5 . its about 8 bucks and usually at the place where they havbe all the gauges on display hanging up collecting dust.

u may have to go to a few different ones.

I suppose I'm just content using something that shows I have pressure - a 2002 LS1 oil pressure sensor. My original 87 sensor wasn't that accurate, so perhaps I don't know what I'm missing.

Why use the thirdgen sensor? Is it that much better?

I doubt it - it seems more likely that it's just something that works with the stock gauge... Me, I'm keeping it simple & using a mechanical gauge (& since I'm keeping the VVT, I'm going to have to sell the 0-100 psi unit I bought so that I can get a 0-150 psi gauge)...

what gauge are you using ?

Oh yea I forgot about that place you gave me the link to. I will call them today and see if they have what I need, if not I will hit up O'Reilly's right down the street from me. Thanks Melvin.

Perhaps drill and tap this location:

I was actually wondering what that spot was for on the oil pan? I have a hole with two threaded holes next to it down there on the side of the oil pan. Is that for an oil cooler or something? If it is an oil cooler, I wouldn't be doing any harm by simply plugging it right?

It's for an oil cooler if there are two ports on it. Plugging it will prevent any oil from getting to the engine.

The one in the pic I posted is the f-body "turn-around" that routes the oil from the filter to the engine. What looks like a port comes plugged - undrilled and untapped. Here's the "before" picture.

I'm using my original 1987 0-60?psi gauge. Firebirds had the electronic clusters then. With the old TPI - the gauge just pegged out normally and would lower to 3/4-full at a stop-light depending on rpm. I know the needle is moving to the same general location with the ls1 sender, haven't paid enough attention to it to know where it normally reads though.

i used a '02 LS1 Z28 sensor for my LS3 swap. It of course has the right threading and it drives the stock dash gauge fine. it's accuracy i think is close enough for what you use the gauge for

That's plugged? heh I thought it wasn't. Good to know!

Ok so mine has two holes in it, I'm not sure what to do with it though. How will it prevent oil from getting to the engine if I block it off? I thought that's what the oil pickup tube and oil pump were for, explain it to me in dummy terms

after u confirm that those holes are not needed for oil passage. can u have ur machine shop tap and thread that part for some NPT pipe threads.

once its NPT pipethread ur options for adapter are endless.

hell u could probabaly put a custom oil cooler later down the road. for now block one off and use the other with a 90* elbow and use correct sender for ur gauge like five7kid did

OK, what you're showing in your post (above) are the passages in the block itself. Obviously, if you leave it uncapped, you'll have oil squirting out of one of those holes. If you just cap it off, like with a flat piece of metal or similar, then the oil won't get from one of those passages to the other. That's the reason for the piece in the picture below - it's basically just a "U" that directs oil from one of the passages to the other.

What five7kid & I have each done is to just drill into that piece & utilize it as an easy way to get an oil pressure reading from the engine...

Ahh ok that makes sense now. Do you have a part number for that piece by any chance?

so can you just leave the ls1, or truck lq4 in my case, sender there and it will read on the stock electronic gauges? cause mine used to be pegged all the time anyway with the 305. if i can just leave it though, that'd be good. does the lsx or lq4 one go to the pcm, or direct to the gauge in the harness?

I apparently didn't explain it well enough. As V8 said, one passage in your photo is the output from the oil filter. The other is the feed to the engine. The piece I posted the picture of is the f-body non-oil-cooler method of getting the oil from the oil filter to the engine. The factory put a blocked-off, untapped boss on it for some unknown reason, but whatever the reason it makes it a handy place to tap for another oil pressure measurement device.

It came on my f-body engine. I don't have the p/n, but it should be available at the dealer.

From all the disscussions here, I understood that the LS1 sender does not work with a stock 3rd gen gauge.

1st time, alan91z28 and 3.1EyeCandy has confirmed that this is not true

When I cranked my ls1 couple months ago, i was getting no reading at all at the gauge (91 gta gauge) but was getting some reading using a dmm but nothing at the gauge.

I wonder why everyone else is drill and tapping the oil bypass or trying to find a NPT to metric adapter .

I already sourced an adapter and tpi connector and got it wired in.

Nick,
based on this info, try using the LS1 sender and see if ur stock 91 gauge works. report back too.

I don't mind having to get ahold of a fitting that will go from standard to metric if it makes the wiring easier. Does the sender go straight to the dash? If so, then I assume the 3rd gen sender will be easier to mate to the 3rd gen wire for that sender. If you use an LS1 sender, are the connectors different?

I believe it's just 1 wire either way (straight from the sender to the dash). I have an ls1 harness so have no idea if the connection to the sender is different.

i am using an '02 LS1 Z28 stock gauge. it is one wire and goes right to the gauge, on my '85 iroc it goes to C100-E5

with my stock 0 - 60 PSI gauge it is normally in the 40-50 PSI range when running... i have been using this set-up ever since i got my car running this spring

i was going to make an adapter for a stock 3rd gen pressure switch but when i found this worked i figured this was much better and the accuracy is good enough for what you are looking for... ie do you have decent oil pressure

thanks

Hmm, maybe I'll just return the 3rd gen unit and buy one for an LS1 and see how it works.

Guys, you are making this way too hard. As stated by V8 & five7, you can simply drill and tap the oil transfer adapter, above the oil pan, but it MUST be in place. OR as screemingchicken said, you can get the plug,that goes where the stock LS1 oil sending unit is, drill and tap this. I actually made the one for him. The plug can be found at Advance Auto Parts. Its a replacement oil drain plug M16-1.5,cost less than $2. Take this to your machinist, have him tap it 1/8 npt. Or better yet, get yourself a 1/8 pipe tap, a letter R drill bit, and do it yourself. It,s not that hard. Oh if you can't find a letter R drill, a 11/32 will work. Do it yourself and you will have gained a new skill. Total cost should be $10 to $12 and you will have some more tools for later use. Later< Dean.

Blue Z, oil is picked up by the pump,via the pickup tube . It is then pumped to one of the holes shown. If the transfer adapter was left off the oil would be pumped onto the ground.If the hole was pluged, flow would stop here and never reach the filter. The adapter simply links the two holes together. Hope this helps explain, Dean.

Simplest route:

http://www.autometer.com/cat_accesso...il.aspx?vid=58

Hey, does that piece fit the "low oil level" sender location in the F-body oil pan? Anyone know?

No, it does not fit the pan, I will check that size later today and post back.

Sheldon solved that problem, didn't he ,Later, Dean.

Thanks Dean, I appreciate it.

Low oil level sender thread size is M20-1.5, hope this helps, Dean

I'm bumping this thread back from the dead lol.

But I have a question about this fitting. If I already have an Autometer mechanical oil pressure gauge, would I just use this fitting above in place of the ls1 sending unit? I would rather keep my Autometer gauge so if I just have to buy this piece that would be nice. Anyone done this or know?

Oil pressure is oil pressure, the guage doesn't know what kind of engine is making it. So yes, this will work to adapt your gauge fitting to the engine.

I just bought a "Y" connector and some adapters, so I´m running both my stock LS2 sensor to feed the computer some info, and the stock -89 Iroc sensor to drive the gauge. They are located at the stock location by the firewall.

I'm bringing this thread back from the dead again. Does the ECU use oil pressure info for anything, or is this strictly for the gauge? I'm having a hell of a time figuring out whether I should be tapping the oil cooler plug for a thirdgen sender, using an adapter for a sender in the existing location, or just using the existing sender!

Just use the existing sender Jim

don't make things complicated.

its just for the gauge, so just splice it in if yours works. while trying to install the truck sender i had, i broke it in half. i ended plugging the spot on the rear of the block because i couldn't the room i needed to get the 3rd gen sender to fit. from there, i tapped the plug that's above the oil filter and used that spot for the factory 3rd gen sender.

Thanks guys. I'll plan on using the LS sensor until that becomes a problem.

I just bought an adapter that the 3rdgen sender screws into then screws into the plug behind the intake manifold. Everything works perfect...

Bought my adapter for my oil pressure and my coolant guage sender here. http://hotrodlane.cc

Jim, if your using the LS1 pcm it does NOT use any oil pressure info. I used my thirdgen sender so my thirdgen gauge would read correctly. I posted a cheap way to do the sender hookup in a earlier post.