I wanted to get some advice: I installed a 2004 vvt engine into my 1990 and will be swapping the vvt head out for a bp-4w. As far as I can see (with the engine in the car and shining a flash light) the VVT oil feed comes off the block and the oil pressure sender threads into that oil line. The question is, can I just remove the oil feed that extends from the side of the block near the oil cooler and pressure sender and re-install the pressure sender or is there some BP-4W specific hardware that I need to buy?

thanks guys. Anyone want a 90k vvt head?

 

You should just be able to screw the oil pressure sender into the block where the line fits. I have also shot you a pm.

 

it looked simple but I have made bigger mistakes on simpler things....thanks for the reply!

 

The threads on the VVT block is BSPP (Parallel thread) whereas the pressure gauge is BSPT (tapered).

Just an FYI if you find that merely threading it in doesn't seal as well. Why not keep VVT out of curiosity. How much are you getting rid of the head for?

 

psyber 0ptix: I am more concerned with simplicity than gadgets. The miata is simple...and I feel the 4W head is more what I want for my car.

I would imagine there is an adapter that can solve the sealing issue, correct?

 

Adapters will be a bit convoluted. It's tough to find BSPP->BSPT adapter as it's more common to go fron NPT to BSP.

Just throw on some Teflon paste and see if it holds. Some folks report using the parallel thread in the tapered hole just fine, I don't know if this holds true the other way.

If you did go with adapters, you'd be adding more failure points going from male bsp/male npt + npt union + npt male/bspt female.

 

When did this change first occur on the block? 1994 when they switched to the 1.8?

 

As far as I know, all NB2 blocks are parallel thread (bspp) and sealed with a crush washer/banjo bolt to the hardline for VVT feed.

All other non-VVT blocks where BSPT since that location just held a pressure sender.

I have a 94 block and had to run a PP tap through for the banjo bolt.

 

There must be two style oil pressure senders in the early cars. My oil pressure sender from my 1990 threaded directly into the 2004 Block.

 

It will thread in I believe. But I think one is tapered and the other is not, same pitch, but could lead to sealing issues.

 

Both senders are the same thread, tapered. It will thread into the parallel hole because it's the same thread pitch, but the parallel threads are sealed with a crush washer...because parallel threads.

Tapered is supposed to be self sealing (with some thread treatment). Conical shape will cause the threads to bind tightly under torsion to help sealing.

 

Aofdiasfoinsfoinsfisdnfoisnfosindf.

Is this where my ******* oil leak is coming from!?!?!?

[utag=shuiend]shuiend[/utag] [utag=aidandj]aidandj[/utag] we may have found my leak.

 

Are you using a pressure gauge sender with tapered thread on a vvt block without the vvt hardline?

The vvt oil feed connects to the block with parallel thread, sealed with crush washers. The gauge location on that hardline is tapered. All gauges are 1/8bspt (tapered) on the miata.

Most aftermarket gauges are 1/8npt (tapered). The difference between the npt and bspt/bspp thread is one thread in its thread pitch