slowmx5

I am about to re-locate my turbos oil supply line to this sandwich plate. It has four 1/8" NTP ports and I know that the FM oil supply line fitting is not 1/8" NPT so I need an adaptor. Before I can order it I need to know what the thread specs are of the FM supply line. Can anyone help? (I sort of recall it being something like 4AN).

TurboRoach

iTrader: (3)

Its something like M10x1.25 (I think) to -4 AN. If you're talking about the feed on the hot side of the block. I have an extra 1/8NPT to -4 AN if you want it.

Stephanie Turner

What year car? It could be a 1/8 BNPT.
Stephanie

mx5newbie

iTrader: (1)

subscribing... I need to know what size the fitting is for a 1.6L oil feed port on the drivers side as well

slowmx5

An update on this (thanks for the replies). My reason for moving the source was that I installed an oil pressure and temperature gauge - although I selected the white dial and blue LED version. Looks OK IMO, although I prefer analogue gauges (I'm running out of room and needed the dual nature of the gauge).

I have fitted the additional sandwich plate, but decided not to take the turbo's oil feed from it. My reasoning being that oil from that source is pre-filter. I also decided against taking the oil pressure feed from it as that point is again pre-filter and in my case also pre-oilcooler ('T'stat sandwich plate is on top of the new sandwich plate). So in summary the new gauges pressure sender is installed into a 'T' into the block with the turbo oil supply taken from the side port of the 'T'. The 'T' specs are 1/8 BSPP female (for the pressure sender), 1/8 NPT female (for the turbos line which is 1/8 NPT to -4AN) and 1/8 BSPT male to the block.

The new sandwhich plate ports (i.e. all female) are used for the new gauges oil temp sender (1/8 NPT) as this is representative of oil temp pre-cooler and the OEM gauge sender (1/8 BSPT).

The stock gauge is relatively accurate by the looks of it, although as soon as the oil warms up and the 'T' stat opens and oil is diverted through the oil-cooler I see a significant pressure drop across it with approx 42psi at 3000rpm on the new gauge vs the stock gauge reading of about 53p- 57si (at 1000rpm the difference is less 24psi vs about 27 to 28psi). I'm going to try and reduce that difference by removing the forged 90 deg fittings at the cooler end of the lines and replace them with swept 45 deg fittings. Hoping for a 2 or 3 psi improvement???

neogenesis2004

iTrader: (12)

I'm pretty positive that all sandwich plates provide filtered oil. The center threaded portion is what unfiltered oil comes into the filter through and the filtered oil goes to the motor through the outer portion. The outer portion is where the ports on the sandwich plate are.

slowmx5

Ah, OK - my understanding was the reverse, that the pump oil came up the outside, through the filter media and down the central pipe to the engine. Perhaps someone can confirm.

slowmx5

To be sure that my memory wasn't playing tricks on me I've just checked the oil pathway diagram in my FSM. The oil definitely flows from the pump into the outer portion of the filter and then back to the block via the central pathway. The pressure as read by a sender taped into the outer circumference of the sandwich plate will not be representative of the pressure within the block and feeding the cam and main bearings etc. Taping here to supply a turbo with oil will also be passing unfiltered oil through the turbos bearings (if that worries you).

Keith@FM

iTrader: (1)

The feed lines supplied by FM use an AN -4 fitting on each end. To plug that into the block on the exhaust side (1990-94), you'll need a 1.5x10 to -4 adapter, $6.95 from FM. To use the oil pressure sender hole (1995-05), the thread there is a BPT.

NPT to -4 fittings are pretty easy to find.