jbherri2

iTrader: (1)

Hello All -
1985, S, 12a, 85,000 miles (ish, the car isn't at my house at the moment)
I've been having the suspension worked on, that thread here:
https://www.rx7club.com/1st-gen-gene...-need-1146014/
Thank you all for your input on that - I think I'm on the right track with the suspension work.

But ... while the car is down for service, it seems like a good time to go ahead and replace the clutch. Figure I'll have the transmission drained / filled, deal with the clutch, address an oil pan leak ... all in one go.

So, on to the question(s):
My car is not daily driven (a shame, I know). It's 12a, non-ported, factory Nikki. If I were to replace the clutch and related parts, am I ok with the Exedy "Stock" clutch kit? If I use this kit, do I need to get a replacement counter-weight? (All these years, still a noob). Is it really worth upgrading to the Exedy Stage One and buying the (what I think is pricey) counter-weight from Racing Beat?

Here's my shopping list, so far:

racing beat
1668-10-556A
Oil Seal Rear Stationary Gear

racing beat
12654
Clutch Master Cylinder - RX-7 1984-85 12A

racing beat
12655
Clutch Slave Cylinder - RX-7 1983-85 12A

MazdaTrix
0437-17-335A
71-85 Rear Transmission Seal

MazdaTrix
0603-16-103
69-91 Manual Transmission Front Cover Seal

MazdaTrix
10008
83-91 N/A Rx7 Exedy Stock Clutch Kit

I'd value your input.
Thanks!

Toruki

Don't know the part number but it might be worth getting the pilot bearing and seal directly from Mazda or Mazdatrix. The one in the Exedy kit can be incorrect so I've heard. I really like the stock clutch.

This thing worked really well pulling the old pilot bearing: https://www.harborfreight.com/slide-...-pc-62601.html

Are you doing it yourself? You should!

Edit: Forgot to add this: https://www.mazdatrix.com/product/to...ing-installer/

j9fd3s

iTrader: (3)

Daiken/Exedy is the original manufacturer, so yes you should be really happy with that.

and its the same clutch as the GSL-SE now, so no worries about overpowering it or anything

LEGALIZECHEY

iTrader: (1)

From what I’ve picked up, the counterweights only need to be changed if you are going to a lighter weight flywheel....

jbherri2

iTrader: (1)

Thanks all -
One more question (maybe one more) - what would be your preference for transmission and differential fluid?
I did order the stage 1 clutch and associated parts. I figure the original clutch lasted this long ....

tommyeflight89

iTrader: (4)

Exedy stage 1 is a good choice! I think only difference is a bit more pedal effort which I like.

Also can get a new OEM clutch flex line, it goes from your firewall hardline to the slave cylinder. Also, look out for the bolts that bolt the slave cylinder to the trans. They thread directly into the soft aluminum casting (M8 coarse thread I believe) and can be really easy to strip out . I ended up heli-coil repairing mine when I dropped the trans.

Redline is a good choice for trans and diff fluids. Grab the specs and volumes required from technical Data for your year (dont think it changes anyway). I run MT90 in the trans.
Foxed.ca - Mazda RX-7 Manuals

jbherri2

iTrader: (1)

I did order the braided clutch line.
Noob question - trans/diff fluids can by synthetic, correct? No debate like w/ the crankcase oil ...?
Also - just straight 90 weight - or 75/90, if I can't find 90?
thanks again!

Toruki

75W90 synthetic is fine in my experience. For the diff, if you have the LSD you need the gear oil with the "stuff for clutch packs" <---technical term.

jbherri2

iTrader: (1)

Very technical
I have the base model, so it's not LSD. Sadly.

j9fd3s

iTrader: (3)

synthetic is better here. its interesting i looked through the specs and they all want a 90 weight oil, except 1983 which is 80w90. i've been running 75w90 for years!
i picked redline as an example, feel free to buy whatever brand you like, but if you read the oil spec it says GL-4 which is what Mazda wants, and then it says 90 SAE, so you could use that . every oil company has a website like this with the specs, and its also usually on the bottle as well

TimNH

I put a Racing Beat Street/strip clutch in back in 1997. It is still going strong and has about 65K on it. I've had to replace the clutch hydraulics a number of times though. It used to be every 12 years, but the master cylinder I put in last year has failed already after one year and 300 miles. The seal was degrading and you could see it in the fluid. I'm convinced the same thing happened to my friend with his Cosmo. I noticed that I had used Dot3 fluid but it was synthetic. I'm not sure if this had anything to do with it, but I did use a non-synthetic fluid this time.

Ckforker

My synchros were grinding a bit from 1st to 2nd. I went 75% 75/90 and 25% automatic transmission fluid. Works great, especially in the cold weather.

Many late model manual trans run pure automatic transmission fluid. My last 626 did, maybe an 98? Hard to remember.