Revving Miazda

[bikin' Ed]

Recently bought a '96 Mazda Miata (MIAZDA). It's a like an open air go cart and lots of fun. Right now it's averaging about 32 mpg--bone stock except tire pressure.

The 1.8L naturally aspirated, FI engine seems to have plenty of torque for it's tiny pay load. Unfortunately, it's geared really short. I'm running 3000 rpm at 60 mph in 5th.

I'm hoping someone with mazda expertise can tell me where is the best bet to get taller gears, manual trans? or rear end? or both?

Thanks, cuz I know someone out there will have great ideas.

[MazdaMatt]

you may be better off looking at the Miata club websites for a question like that.

[MetroMPG]

Probably right, MazdaMatt. Be prepared to be flamed or accused of heresy when you ask though.

A taller 5th would be a great mod. I'd be inclined to choose 5th vs. a taller final ratio, because I'd think you'd want to retain the sporty, close ratio character of the first four gears. I have a relative with a '90 Miata, and it's a hoot to drive.

[MazdaMatt]

I don't know about the miata, but my Protege's first gear is a little too short for any application, racing, dd or FE. A FD gear change in my car would fix first, but make the rest too tall for racing, not bad for DD and FE though.

[sohl]

MazdaMatt: I second that. I'd be nice to have a mode for the automatic trans to "skip first" and start in second instead.

[Will]

I love the "short throw shifting" of the Miata. I wish I could get a kit to make my Metro shift like that.

[Dust]

I know there is a rx7 turbo 2 rear end swap, but I dont know about the 5th gear. The 6 speed swap wasn't really considered a FM mod when I was on the forums last. Good to know they are getting in the 30 for mpg, always read they were gettin high 20's

[SmittyNC]

Hey bikin Ed! I believe the 6MT NB Miatas (1999-05) came with a 3.91 differential as opposed to the 4.30 that was standard on NA Miatas like yours. That would give you a reasonable reduction in highway RPM.

[bikin' Ed]

Originally Posted by SmittyNC

Hey bikin Ed! I believe the 6MT NB Miatas (1999-05) came with a 3.91 differential as opposed to the 4.30 that was standard on NA Miatas like yours. That would give you a reasonable reduction in highway RPM.

Thanks Smitty. I'll be loonikng into that before I bring her back out in the spring.

[MetroMPG]

Smitty - do you know of anyone else who has done that swap for efficiency?

Bikin' Ed - if you do it, be sure to document & post!