Miata issue (slow + high RPM)

[TheButcher]

Ok, so I need some help here. I am thinking of selling my na because of these 2 reasons.

1. If you cruise at 80mph your at over 4k and it sounds like your going to kill it if you do it for a long trip. I feel like I'm beating the crap out if it just driving home from work. (Speed limit is 75 so 80 is not crazy)

2. It's slow. I can afford to turbo it or do a s/c if I wanted to but then I am smack dab in problem ones ass.

I know there are different ring gears but that would make it lose the "pep" the car has. Also the trannies are glass and even the 6 speeds are iffy over 300whp.

So here's my problem. I love this car. I have 5k or so in just the suspension and it handles better than my old gt3. But I am sad about the beating it seems to take just driving home. If I was on a track I wouldn't feel so bad. So give me hope or ideas to remedy my situation that are not V8 swap or some other cray swap. I am looking at doing the k24/20 swap when that's ready and have contacted him showing interest. But, that's a last ditch plan.

Sad Miata owner.

[ibid]

Ouch

I hope the K-swap works out great for you. Sounds like it is the answer to your dilemma though from everything I heard about it. Our Friend Austin Cabot did the K-swap and was all smiles about it FWIW. He has since sold the car though.

[— kung fu jesus —]

S2K or C5 vette.

Unless you really like the car that much, a turbo + 6sp + 3.9 LSD. Probably looking at about $5-8k

[— Phatmiata —]

S2K or C5 vette.

Unless you really like the car that much, a turbo + 6sp + 3.9 LSD. Probably looking at about $5-8k

Start with a 6-Speed transmission and see if that helps the highway commute, its still a LOT cheaper than buying another car!!

[— kung fu jesus —]

If you are going to add power, go with the 6sp anyways. While I enjoy the shift feel on the 5sp more, the 6sp is more durable for added power.

[psulja]

do not start with a 6 speed. the 6th gear is not at that much of a different ratio than 5th in the 5speed. Start with a 3.9 or lower rear gear ratio while keeping the 5speed.

If you can afford to turbo, why not just turbo? You say 300whp, have you been in a miata with 200whp? 230whp? 250? My car is estimated to be making 230whp right now and its faster than what the average person needs on the street. Its faster than any of the cars I've come across so far, and that was on crappy all season street tires. These include an R32 GTR, IS350 that was spraying, e46 M3, e39 M5, and much more. It also ran 12's in the quarter.

If I was you, I would turbo it, swap in a 3.9 torsen, or 3.3 from miataroadster if you really want to drop your rpm's while cruising. If you do the 3.9, you could probably stick with a 5 speed below 250whp, anything more it would actually be worth swapping to the 6 speed and 3.3 or 3.6 rear end because you wouldn't notice the loss of acceleration over the added final drive. But start with 220-230 whp and I think you'll be pretty happy.

Also, you say 6 speeds are iffy over 300whp. No they're not. There are people running 400whp on a 6 speed without issues. 300whp should not be a problem for the 6speed, and I think you'll be happy with less than 300whp anyways. This is a street car, right? I don't see you blowing up a 6 speed with 300+whp. At ~230whp, and constant hard launches/shifts, I haven't had an issue with the 5 speed yet either.

[— kung fu jesus —]

Further on the 6sp, I know Andrew at Trackspeed highly recommends the 6er for any turbo Miata. Endurance race teams like 949 Racing ONLY use 6 speed trannys because of their longevity over the 5er. If want to go full-retard, there are a number of documented tranny swaps using the turbo FC RX7 manual transmissions (with or without the FC diff) with a turbo'd Miata.

[psulja]

Yes, the 6 speed is perfectly fine for making big power. Do not be worried about it.

But, do not only swap the 6 speed hoping for a drop in cruising rpm's without a change in your final drive.

Mind you, I did sell my 6 speed and have a TII rx7 transmission on the way, but that is because I am indeed going full-retard with my car.

[psulja]

[TheButcher]

So, if I do a 3.9 (or 3.3 not sure which you recommend) and a 6spd the car will be more of a cruiser? I would do a motor and turbo if I could really change the rpm issue. It is a street car. I have a gt3rs for the track car. I love 90's cars my wife thinks I'm crazy. Even my 87 GN does 2500+/- rpm on the freeway at 75. But my Miata is my baby.

Thank you for the help.

[— kung fu jesus —]

The 6sp will help some. Can't remember what my 10ae cruises at but this may help you:

http://www.flyinmiata.com/tech/gearing.php

[— Phatmiata —]

Check out this group buy ASAP!!! http://mazdaroadster.net/showthread....nion-group-buy


Looks like with a 6-speed would be the way to go!

[psulja]

6 speed with 3.3 if you are going to go turbo and actually make power.