24 replies to this topic

[Sacslider]

Has anyone checked the stock oil pressure sender to see if it is accurate enough to use with a data system? I know the stock gauge is not accurate but dont know if it is a function of the gauge or the sender. I was hoping to use the stock sender and custom map the voltage to the appropriate psi. I am hoping someone has tried this and will tell me if it worth the trouble or not before I invest the time.

Thanks

[Johnny D]

Just looking at Miata.net.

on/off type sender.
J~

[Tom Hampton]

Depends on the year. Through 1992 (at least) they have a real sender and guage that reads real pressure. I don't know exactly when they changed to the switch. But, I have a 1992, and it reads actual pressure.

I'm sure Dave W (who knows all) will eventually chime in and site chapter and verse.

[Johnny D]

Looks like he has a 92 in SCCA, my bad.
91 on his profile?
J~

[davew]

I would not use the stock sender in a data system. For what you are spending on data, whats an extra $80 for the correct plug-n-play sender.

Dave

[dstevens]

I've been using a regular VDO 80 psi with an AIM system, no problems. Under 30 bucks out the door at NAPA.

[Sacslider]

Do you have a model or part number for the VDO unit? The counter dweebs around here cant help ya without a make model and vin number. Sigh. I miss the real parts guys...not these high school kid swith an attitude.

Thanks

[dstevens]

Summit and Jegs have them as well, I don't have the part number handy. Google it and you'll get the right one. Our local NAPAs are all owned by the same company, they aren't corporate stores and they cater to service pros so they have things that a consumer NAPA may not have. It's the same VDO sensor that AIM sells in the kit with the cabling for 80 bucks. I have a bunch of cable that I used to make the leads.

[davecarama]

Depends on the year. Through 1992 (at least) they have a real sender and guage that reads real pressure. I don't know exactly when they changed to the switch. But, I have a 1992, and it reads actual pressure.

I'm sure Dave W (who knows all) will eventually chime in and site chapter and verse.

All of the 1.6 cars have the real pressure sender. I think they switched at '95 actually (so I think the '94 cars had them too).

If you swap the sender into your 1.8 car, you need to swap the gage too. VERY simple mod and what the Miata.netters do all the time.

Dave

[Sacslider]

Will the VDO unit work for fual also?

[davew]

Please remember that the engine block is threaded British Standard Pipe Thread (BSPT) and not National Pipe Thread (NPT) that the aftermarket senders use.

I don't know if the aftermarket units would be compatible with gasoline. Electricly, they would work. Who wants to be the guinea pig and test if gas will damage a VDO sender????????

Dave

[dstevens]

It will work with gas, the issue would be in the scaling. There are 2 units used for oil, one is a 5 bar (80 psi), the other is a 10 bar (150 psi). They have a few others too including M10 threads. They do have a fuel pressure unit that is a 2 bar (29 psi). VDO's site is long on style, short on substance, here is a link from Summit http://www.summitrac...rts/VDO-360043/

For the oil sensor adapter there a several places to get a bspt/npt adapter and most of the shops have a relocation kit, I'm pretty sure Wheeler has one as well. I got the info to fab mine from Roger Caddell's site before they closed. Good to see he got a gig with AIM, he's now the trainer and a track support guy. It's easy to do, some hose, adapters and something for the firewall to hold the sender. Or you just pay someone that has them already.

[schmoo]

I'm getting ready to mount an MXL in place of my stock IC and will be changing the oil pressure sender to a VDO unit. Since I got the VDO unit used, it's threaded ended isn't compatible with most relocation kits I've seen. Therefore, I'm having to make a custom AN3 line to go from the block to the pressure sensor. Can anyone tell me the spec of male fitting I'll need to thread into the block? I know it's bspt threading, but what is the diameter of the fitting?

Thanks in advance for your assistance.

[dstevens]

The VDO sensors come in at least M10 or 1/8" npt. The block connection is 1/8" bspt also called bsp. You can get the fittings at either your local industrial supply or at Pegasus. I used AN fittings in the stock car but haven't in the Miata. A bit tough to build at first but a quality fitting.

AN3 to male 1/8"-28 BSPT at Pegasus is about $7.50
http://www.pegasusau...sp?Product=3230

[schmoo]

AN3 to male 1/8"-28 BSPT at Pegasus is about $7.50

Thanks dstevens. In your quote, what does the -28 mean?

[Jim Boemler]

28 threads per inch. Beware that in pipe threads, the 1/8" is an inside dimension, so the threads are a lot larger.

[schmoo]

Thanks everyone!

[schmoo]

Very frustrated. Local shop made a line for me, so I went to do the install this past weekend and discover they messed it up and used 1/8 NPT on the block end. Went to see them and they don't have BSP fittings. Then why did you say you could do it????

Anyway, I need to put the stock sender back and put oil back in the car for an autox this weekend. I've ordered pars from Pegasus Racing to do it myself.

Anyone know if I can pull the stock sender with oil in the motor and not have a deluge oil come out at me? If I can avoid loosing a fresh load of oil, it would be nice.

[Jim Boemler]

Anyone know if I can pull the stock sender with oil in the motor and not have a deluge oil come out at me? If I can avoid loosing a fresh load of oil, it would be nice.

Is the sender above or below the level on your dipstick?

[schmoo]

Is the sender above or below the level on your dipstick?

It's above the bottom of the dipstick, but below it's handle.

Certainly, it's above the oil pan, but so is the filter and there's a good amount of flow when you pull that off. That said, it's above the filter, so probably less than the filter.

I can speculate all day, but hoping someone here might have tried it, for better or for worse, and can share the results.