Johnyquest

I'm in the middle of my turbo-civ project here. I've talked to a lot of ppl and finally got my **** together (almost). I'm about ready to bolt my turbo up on the car, and I have a little question for you guys. I've read on some posts the the oil pressure sensor on the back of the block is 1/8th NPT, and some other people said its BSP or some ****. Now I have NO CLUE what either of these are (NPT = normal pipe thread?) but bsp no idea. I went to home depot and got a 1/8th brass T, and a short 1/8th npt brass nipple to put into the tee and into the block... But then I read that the block is indeed NOT NPT. SO, what is it? What screws into the block? I don't wanna wreck the threads, and even if I did, that'd still mean that the Oil sensor wouldn't screw into my 1/8th npt tee, either. What do I do? are the threads on the block 1/8th npt like I thought, or somthing special?

CzanSOHC

the oil pressure sensor is a 1/8 Bspt (british standard pipe thread), I bought an adapter kit that goes from 1/8 bspt to 1/8 ntp . go to jackmoves.com, in his turbo discussion forum gives the part numbers for these parts.


[Modified by CzanSOHC, 11:04 PM 1/2/2003]

0KStuned

Yes, the fitting on the back of the block for the oil pressure sender is BSPT but it is "British Standard Pipe Taper" you can use NPT as the threads are VERY close, it will even screw in and not leak, it just isn't perfect. The BEST way to do it is get a BSPT to NPT adapter from Z10eng.com and then get a readily available 1/8 NPT to -3 or -4 AN adapter (whichever size your feed line) to run your oil feed line to your turbo. EASY!

Johnyquest

Doesn't this mean that i'd need TWO of these adapters, since I need one to screw into the block and one to make the oil pressure sensor screw into the TEE? Is the Oil pressure sensor a male fitting or a female fitting? I'm assuming it's a male fitting and the block is the female side... So that'd mean that I need a 1/8th NPT --> BPT adapter from TEE to BLOCK; and another 1/8th BPT female --> 1/8th NPT male peice for the oil sensor to screw into the tee?

0KStuned

The oil pressure sensor is a male bspt fitting. As far as you needing 2 of these special adapters, I would say that it is unnecessary, the reason you really should use one of the on the back of the block is because the block is prone to crack when you hang a lot of weight on it like a brass tee with an oil pressure sensor on the end, and then screwing in an NPT fitting, simply adds more internal stress because it is crushing threads to thread itself in. It may not seem like a lot, but it is enough to contribute to possible cracking. Again, plenty of people are screwing in NPT fittings into bspt threads and it is working... But the "RIGHT" way to do it is to use the correct BSPT threaded adapter or if you can find bspt fittings (good luck!)

Here is how mine is set up and how I would recommend you do it:
1/8 bspt (female) to 1/8 npt (male) adapter from z10eng.com to screw into the block, then a 1/8 NPT to -3AN (or whatever size your oil feed line is) straight adapter, then approximately 1.5 feet of stainless line to a 1/8 NPT 3 way aluminum "T" remotely mounted on the firewall with some slack, so that there isn't a lot of weight hanging off the back of the block, get 2 more 1/8 NPT to -3AN adapters and screw them into the "T", and then screw in your oil pressure sender into this "T" (this is where the other BSPT-NPT adapter is optional), then run another 1 foot (approximately) to your turbo inlet (and buy the appropriate size adapter for whatever size your turbo oil inlet is.