I have a '89 GTUs, and i had a few questions about my brake master cylinder. does my car have the s5 n/a brake master cylinder or does it have the s5 turbo master cylinder? Also i was wondering if my car does have the s5 n/a master cylinder can i install the s5 turbo master cylinder with little/no modifications? any information would be greatly appreciated.

Izzy

 

If your GTUs has the 4-piston front caliper system I believe you will need the Turbo master cylinder. The Turbo MC is different from the non-turbo equivalent. MC selection depends to some extent on whether or not the car has ABS and/or AAS. Give Mazdatrix a call (562-426-7960) to verify before ordering. See this page to see what I mean:
http://www.mazdatrix.com/j-3brake.htm

 

Thanks for the info, i'll post what i find after i call them

 

Well i just talked to Mazdatrix and they told me to use the s5 n/a brake master cylinder. so i guess thats what i'm gonna end up using. thanks Go48

 

Hmmm, I thought the GTUs had the Turbo brakes. Guess I was wrong. First time.

Edit: Well don't be surprised it you really do need the Turbo MC. See the sheet at the bottom of the following page:
https://www.rx7club.com/showpost.php...27&postcount=6

 

The gtus, vert and turbos have the same brake system. The only difference is ABS. As for the single piston calipers they use a different brake booster.
Thanks Robert

 

i know my car has 4 piston calipers up front just like the tII. i think the guy at Mazdatrix misinformed me. So should i be using a turbo master cylinder? Btw my car is non abs.

 

You'll use a na master cylinder ment for a 4 piston caliper.

 

ok, thank you

 

People forget that the GXL, 91 Coupe A Package and other NA cars also came with 4 piston calipers. 4 piston calipers do not represent Turbo brakes, I'm not sure where that started.

Use the NA Master Cylinder, but look at Mazdatrix's site and see if there's a difference in the MC between single piston front brakes and 4 piston front brakes for NA cars.

 

Thanks everyone for your input, i'm buying a n/a one.

 

I did a 5 lug Swap with 4 piston calipers up front.I used the N/A master cylinder and it Works Just Dandy!.I have done THREE swaps like this and No problems.I haven't however done anything with ABS crap on it.(old school.Abs wasn't invented when I got my Licence!).