superdan50

iTrader: (3)

i was wanting to know if there are any options other than the 6 SPEED DOG ENGAGEMENT GEARKIT, that will offer a 6 speed for the fd? something like a vette tranny or sumthing along those lines. mostly i want better mpg without paying $8k. mild modification to the bell housing is not too big of a deal.

Miata_mx5

Getrag V160 from a MKIV Supra/JZA80 i heard will fit with some modifications.

That gearbox is 4000 dollars new anyway.

NissanConvert

iTrader: (1)

i've never heard of a "cheap" 6 speed. If you want better mileage get a boost/vacuum gauge and use it to tune the loose nut behind the wheel.

oo7arkman

iTrader: (2)

^^^^

And 6 speed trannies have been discussed many many times on here. Conclusion to all those discussions: "sure it can be done but it is very expensive.." If you are needing better gas mileage why are you driving an FD anyway? The rotary is not exactly known for great gas mileage. If you need that, take the money you were going to spend on the 6speed tranny and buy a beater civic or something for a few grand. Problem solved...

RX-Heven

iTrader: (1)

pm'd you

superdan50

iTrader: (3)

i suppose cheap was not what i meant, i meant less expensive. why y dont i buy a beated civic more insurance (not the main reason), but most of all how often do you see a civic and have this reaction, WOW LOOK AT THAT CIVIC, MAN HOW I LONG TO OWN ONE... exactly you dont and unless ur full of it never will. and in addition to better mpg is the bad *** factor.

if i were to go the way of the supra tranny is there drive shaft modification? and how mild (or not mild) is the modification.

OTT

iTrader: (1)

^ I'm sure the length would change and you would need a new transmission yoke. Easily accomplished by a drive line specialist but im sure It would cost 100-200 bucks.... are Rx8's 6-speeds?

oo7arkman

iTrader: (2)

Of coarse you don't get the same reaction while driving a civic... And really gas mileage is not going to increase THAT significantly with only the addition of a 6speed tanny.. Sorry to burst your mpg bubble. If you need better hwy gas mileage out of a tranny you could always change the final drive gear but the us version of the FD already has a final drive gear with that in mind (differing from the non-US FD's with a more aggressive final drive). Driving a true sports car and wanting great gas mileage just don't go together... the only way that works is controlling your foot. Get a good DD, for gas mileage and drive the FD when you feel like being a badass...

And yes the RX8 does have a 6 speed, there are MANY discusions on here are to if that would work. IIRC, no it does not and even if it would it is FAR to weak to uphold the power delivered by a more than stock FD. But please look it up to make sure what I just said is correct if you are interested in that route. It was a long time ago when I read that.

MOBEONER

iTrader: (18)

hahahaha good one.

855m0n0

iTrader: (1)

You could always put an LS1/T56 and have a car that gets 35mpg on the hwy....

AnArKey

iTrader: (1)

LS1/T56 FDs really do that well?

Miata_mx5

Rx8 does have a 6 speed. Yes it does work with the 13B-REW.

It is a little difficult, but has been done before.

No, it's not good for higher power levels. Which is why the Getrag V160 is a much better option. I am sure a custom driveshaft needs to make. I know someone makes a bellhousing adapter of some sort for that gearbox (a search is probably in order). Either way it's some custom work, but it's a bulletproof 6 speed gearbox.

I guarantee an LS1 won't get 35 mpg with the way i drive.

rrw

iTrader: (2)

just having the civic as daily driver is where i think he was coming from. i would rather have starlet but a little hard to find cheap

BC-FD3S

iTrader: (2)

the cost of fabbing up a 6 speed also worth a lot of gas... think about it..

oo7arkman

iTrader: (2)

Thanks for the clarification on the RX8 tranny. I couldn't remember if it worked or not.

35mpg on an ls1??!!?! I don't think I have ever seen one get that good of mileage before. I am doubtful but that is kinda interesting....

cptpain

iTrader: (1)

I VERY HIGHLY doubt that. If it was in fact true, the resell price on one would not be just a tad under $20k for a C5 Z06, and there would be MORE of them than pesky little turbo civics

NO. Don't believe him. the BEST an LS1 vette will do is MAYBE 30mpg WITH mixed driving

dgeesaman

iTrader: (7)

Why do you think a 6th gear will help mpg?

Dave

Archie

iTrader: (-1)

36mpg ROFL...yeah, in a wet dream.

Sometimes I have to wonder where you guys pull information from (most likely that dark cavity between your crack).

A good tune along with cruise control does wonders for your MPG.

MOBEONER

iTrader: (18)

rx7= rotary
muscle car = v8
remember that.
regardless of how unreliable the rotary engine can be going v8 is like a cop out.
just my opinion.

gracer7-rx7

iTrader: (16)

You guys should spend some time reading the 2 tranny threads in the 20B section. Click on Search > Advanced Search.

There were a couple of good ones in this section also but they are buried within the redundant threads people create one a month about a 6 speed swap instead of searching for the info that was already posted about it.

Wargasm

Better MPG? Hah.

The factory 5th winds out to something like 205-210 mph at 8000. It's already a very "loafy" highway slowpoke gear.

If you want better mpg, run skinny tires (stock size - not some big ones), slow down, and don't accelerate quickly. Of course, you need to make sure the car is running perfectly.

Do all of this and you might get... I dunno... 25 mpg?

Sorry but FD + Fuel Economy = good luck.

Buy an old Civic to daily drive if you have fuel economy issues

AnthonyNYC

iTrader: (3)

Good advice, I get about 22-24mpg. As a test I wanted to see what the best mileage I could get. With no boost, all highway too and from work, with af's in the high 14s low 15s I would get anywhere from 22-24mpg.

That was short lived, I am back to 12mpg with normal driving and 11/12's Afs under cruise with E85 now.

Anthony

superdan50

iTrader: (3)

i was hoping that a 6 speed would have a longer final than the stock fd tranny, how ever if the best option is the v160/v161 than the fd's final is in fact better for mpg. and finally i dont know how much truth this holds but i also figure when driving on the lower engine speeds could also help w/ engine longevity.

ptrhahn

iTrader: (9)

Why would you want a much longer final than stock anyway, it's a pretty tall gear. Many people put in a SHORT 5th.

If you're really stuck on this, you could put a 3.99 diff in, but that and/or the Supra tranny are really not good ideas, and you're not likely to actually save money OR add any longevity over even a significant Period of time.

Stop over thinking it, and leave it alone.

Dudemaaanownsanrx7

iTrader: (23)

2 things, the amount you will spend will offset pretty much anything u will save. Say you spend 4k on a tranny swap. How much gas can you buy with $4000? at current prices you can buy like 2500 gallons, if it goes back up to $4 you can buy 1000 gallons. Now how much would you gain 1 or 2 mpg tops? that could save you maybe $5 each time you fill up at $4 a gallon. say you fill up once a week. that means your tranny swap will pay for itself in 13.3 years. Maybe less if gas goes higher then $4 a gallon in that time. But when you factor in inflation it would probably take even longer.

second if you only swap in the supra tranny and don't change out the rear end gears you will be turning higher RPMS then you are now. The supra tranny has shorter tranny gearing and a taller rear end gear. So now you're looking at even more hastle and cost. The idea of doing this swap to save money is MAJORLY flawed.