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I have a NB8B throttle body with original TPS. I've had a great deal of trouble finding a replacement NB8B TPS but I seem to be able to find bucket loads these off NA8's.

Could anybody confirm whether the NA8 TPS will fit onto a NB8B throttle body? I know the wiring is different, I'll just need to splice my wiring loom again.

Compared my '93 NA8 TPS to a '99 NB8A TPS & the former is larger both in width & length, so not a direct fit. Don't have a NB8B TPS, so can't say if it's the same as an NB8A TPS.

The early NA8s used the same connector on the ECU as the 1.6 (i'm guessing a 1.6 ecu remapped) ..

I wonder if early 1.8s had the same TPS (on/off) as the NA6's or if they had the same TPS as other NA8s.

Does anyone know?

Sorry doesn't answer original question but might help clarify 93_Clubman's investigations.

Okibi wrote:I wonder if early 1.8s had the same TPS (on/off) as the NA6's or if they had the same TPS as other NA8s. Does anyone know?

Oki, my understanding is all NA8 TPS were variable, even though they changed to a upgraded bit ECU chipset at the beginning of '96 in Australia (Aug '95 in Japan).

Had a look at a cannibalised (minus TPS) NA6 TB, & two of the mounting screws for the NA6 TPS are the same distance apart as the early NA8 TPS. The diameter of the circular part of the NA6 TPS mount on the TB is also the same as the early NA8. However, going by the shape of the mounting surface on the NA6 TB, there seems to be extremities on the NA6 TPS which aren't present on the early NA8 TPS.

Btw, just found a very old thread of one of Randy Stocker's interchange guides showing the NA6 TPS:
http://www.aus-cartalk.com/tech/MiataFu ... eGuide.htm

FWIW, the following indicates that 1998-2005 NB 1.6 & 1.8 manual TBs were the same at least in terms of the main body:
http://cgi.ebay.com.au/Throttle-Body-Ma ... 5ad525aaea