Does anybody know of somewhere that i can get stronger axles for a drum-brake rearend? I had a disc rearend but i'm putting together another racecar and so there went that whole deal. I've gone to the dragstrip twice now and both times i've broken an axle. If i launch easy then they don't break, but once it's time to launch hard i break the axle. I've launched hard at the dragstrip twice, and broken two axles, lol.

 

not sure what year you have, but if you don't use the 84-85 axles as they are bigger, if you need more, ganny's speed or something have the 8.8 conversion for a direct bolt in for our cars ... i also think they have the 9" too

 

I have the original '82 12A rearend in the car again. The 84-85 drum brake axles are bigger? But i dont need the whole housing right? Just the axles and carriers. I haven't really messed with the drum stuff too much.

And i definately don't need the ford rearend for a 12A, but once i get ahold of a 20B...........

 

Not interchangeable. What kind of hp/tq #s are you putting out?

 

https://www.rx7club.com/1st-generation-specific-1979-1985-18/dynoed-my-car-today-586486/

 

Thats not a lot of HP to break axles and stuff. I have abused both my RX-3 and FB's with welded rear end, puck clutches, slicks and hard shifting with no problem.

 

Just lucky i guess! lol What do you launch at? My car hooks north of 6 grand with a nice burnout with my falkens. 5500 if there cold

 

gte an 84-85 rearend. GSL or GSLSE. if im not mistaken the GSL has a stronger 3rd member, but the SE has stronger axles. you could also contact moroso for stronger axles built for the GSLSE rearend. also, you could wait as there are 5 lug axles being made by moroso to fit the GSLSE and GSL rearend.

i have an 84 drum rearend. the ring and pinion are bad, but you could have it for free if you came and got it

 

Check this out:

http://www.rx7.org/jes/axles.html

 

dude,
its a drag race...the fastest time, not who can make the most smoke.

 

5-bolt rear axles for GSL-SE rear ends? That means it'll be possible to do a big brake conversion on a GSL-SE and get 5-bolt wheels front and rear...

*plots*

 

^^ correct

theres also a brake upgrade for the rear coming also

 

You should not be breaking axles with that hp. Find another set and inspect them closely. I've noticed on axles that have been abused, they can have a twist through the lentgh of the axle. If you look at the casting/machining marks, there is sometimes ridge or line that runs the length of the axle shaft. If this line has a spiral to it, it is heading for failure.

I discovered this little tidbit on a high school friends 59 Impala after he broke 1 axle and 2 rear ends with his basically stock 348 cu. in. engine.

 

Per conversation with Driftalanta
"Dont know the part number. I called Newport exotic cars, talked to the guy. All i knew was 1.8L miata diff fit. So i bought the 1.5. Its not torsen its clutch type. If you call the guy he set you up w/ the correct diff. If you can wait till monday . I will look in my tool box at work, and see if the part number is one the manual.
I would also suggest the moser axles, I have bent probably 4 sets of stock ones. The moser are only 350 shipped. I have a invoice number you have them copy the order. All you need to have them do is make them 12mm shorter my order. I went longer so i could custom tailer the length w/ the diff out to get as much spline in the kaaz.
part number on manual
DBZ1810"
Moser axles are GSL-SE spec to match the Miata Kaaz splines.
This was the info I got from Adam on his Kaaz install.

 

Heres my stock 84-85 axles after years and years of 300HP and a dozen runs down the track.Never twisted or broken anything out back......


I drove my little V-6 GLC pretty hard with a small axle,small bearing 82 GSL rearend for 10 years, and I never broke anything there either.Sure your not launching too hard,or beating it too much on the streets?
You shouldnt be breaking things with what you got,unless the previous owner beat and twisted everything up, and drag racing just finished it off.Or perhaps you have too harsh a clutch.Remember,its not the power that breaks things, so much as how its applied......

There are 2 styles of rearend,big axle and small axle.
All 79-83 axles are the same size/strength,regardless of disc or drum. All 84-85 axles are the same as well,just bigger bearings and shafts than the previous years.You cannot mix early/late axles and housings with each other,but you can mix 3rd members from disc/drum/SE cars of the same style.

 

I understand that, just saying that the car hooks above 6000/6500 if the tires are warm and sticky, how do they get warm and sticky? Ooooooohhhh a burnout.

I can't see the clutch being to harsh (ACT heavy-duty pressure plate/ACT 4-puck unsprung hub clutch disc/ Velocity Powersports 8.3 lb flywheel) but i could be launching too hard for this rearend, the disc rearend i had was out of a 84 gsl. If i still had it in my car i bet i could get a 1.8 60' without breaking it, oh well, it went to a deserving project.... another ITA car!

I checked the axles for twist, or any other forms of fatigue when i broke the first one, they were both perfectly normal. I thought that the car might have been abused by the original owners grandsons, but everything looked great.

 

Hell,they dont get much more aggresive than that!!.....4 puck disc,unsprung hub,no marcels,hot sticky tires.......combined with a 6000rpm launch......theres the source of your shock loading.

High strung,N/A rotaries dont make much torque,and clutches are rated by their torque holding capacity.A more forgiving clutch will definately make your rearend last longer.
I still run a simple,organic disc, RB street/strip clutch with a sprung hub in my car.Never slips,never complains....and I garuantee I make more torque than you.

 

i was joking about that whole thing about the clutch not being too harsh, but, if i finally figure out how to get some fcking bills paid off that clutch will be perfect for the PP motor i have waiting for a home! But i first want to see just how far i can take this motor i have right now. Since i'm no pro shop with an unlimited budget for R&D stuff takes me a long time, but the knowledge will be useful once i do open my own car shop

 

For drag, I would stay away from organic, RB street/strip and C/F. They tend to slip at 3rd gear, and after a few runs, forget it. Thats the reason why I switched to puck disc and heavy pressure plates.

 

No arguement about the CF clutch,they suck which is why I went with the RB unit.My CF Dual Friction clutch blew apart on a simple 1-2 shift, on the streets no less.The RB unit has yet to give any problems,although Im not much of a drag race fan anyways.

If you want the ultimate in drag clutches,try an OS Giken or similar, dual plate unit.I paid about 400 for it used with flywheel,which was a deal.It had no measureable wear after about a year of hard use.I finally deciding that it was just too much for my streetcar and sold it for 400 bucks!
It was an unsprung hub unit,but since it had multiple plates,it took up the power smoothly,without being too harsh.I just got sick of the stiff pedal and rattley center plate,when sitting in traffic.....