FD rx7 a-spec difference?
 

Hello,

So I've been researching into FDs, but I am not sure what exactly makes the a-spec/99spec different from the series 6 RX7.

I've heard from people saying that the 99spec is just superior in every way, but didn't give me any specifics.:scratch:

This should be interesting.I am an FC Guy.
My Fc is better than everyone else's..Because it is Mine!!
I am starting to like Fd's though.

Better in every way? Over-stated nonsense.
Typical of year to year changes, there were some re-designs that improved reliablity. Like changing the cross-over from using a rubber coupler at the top of the 'Y' pipe to securing it with a bolt-on flange. There was also some marginal improvement in flow, but mostly it was to remove that coupler as it tended to fail regularly with the heat. The 99 spec turbos were a little more efficient, but nothing that most would noticed in the butt-dyno. The 99 spec bumper had a larger opening for air to the radiator and oil coolers. AFAIK, all parts mentioned above are interchangable and can be purchased and added separately ( I run the 99 'Y' pipe and cross-over).
There was a change on the OMP and OMP injector. Later models (not sure what year) had a Mikuni OMP that was supposedly better in some way, but not certain. I know the oil injectors were changed supposedly for better dispersal. But I understand from the Aussies that problems developed with them plugging up because the orifices were so small. Many prefer our older ones.
Internally MAZDA went from 3 pc apex seals to 2 pc for less housing wear and better sealing. But I THINK that was done in 94 or 95.
JDM models had a 5th gear that was lower ratio. Some think that's better, I don't.
Suspension and brakes were unchanged, they did move to 17" wheels. Everything after 95 had the steering wheel on the funny side and didn't have alot of the emissions-related crap that was required for our cars in North America.
Trivia (misterstyx69 probably already knows this) but I'm told that S5 Verts were produced simultaneously with the S6 FD (see below).
http://i1126.photobucket.com/albums/...a_1280_960.jpg

All that I can think of off-hand.