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Dusterbd13
Dusterbd13 MegaDork
11/18/17 8:11 p.m.

So, next challenge car is even more of a mutant than the amc. 

1999 Nb miata with gm drivetrain. 

The trans is out of a 97 camaro with a 3800. Using the stock hydraulic throw out bearing that gm shipped them with.

Now, the fun part:

Clutch master cylinder. 

All i can find on the internet is one bore spec from some discount parts site. They claim the camaro is .75 bore.  Supposedly the miata clutch master cylinder is .75 as well. So heres the questions:

1. Can anyone confirm the sizes?

2. Is there more to the hydraulic stuff than making sure the bire sizes match?

Streetwiseguy
Streetwiseguy UltimaDork
11/18/17 8:17 p.m.

Not really.  As long as the travel of the piston is close, you will only have to figure out how to connect the two.  That might be a struggle, knowing how GM plumbs stuff.

tr8todd
tr8todd Dork
11/19/17 6:29 a.m.

The only other thing to consider is the mechanical leverage of the pedal.  5/8 and .75 are pretty standard bore sizes for clutches.  My LS3 driveline from the 2010 Camaro is .75.  Most of my Brit cars are 5/8".  

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/19/17 7:40 a.m.

I will try to confirm the gm bore size.  I know I have it written somewhere.  I also have the rx7 bore size that every body uses with this setup.

 

Lemme check Monday and I'll get you the info...

Dusterbd13
Dusterbd13 MegaDork
11/19/17 8:18 a.m.

Thanks!

 

So , just as clarification: you sid everyone uses the rx7 clutch master. Is there a Google search on this swap that i should be doing? Because it seems like theres very little information out there on this.....

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/19/17 8:22 a.m.

Sorry, let me clarify.

 

There is a clutch master that everybody running an lsx in an rx7 uses.  The throw out bearings are identical.  I used the lsx swap master for my 3400 swap.

 

I'll go Google it and get back to you.

Dusterbd13
Dusterbd13 MegaDork
11/19/17 8:25 a.m.

Ah! Ok. Thanks!

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/19/17 8:28 a.m.

Hinson supercars uses 7/8 inch bore

 

Hopefully this link works.  This is the master in my car right now.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
11/19/17 8:56 a.m.

You need the pedal ratios, as noted. If they’re out of whack, you can either change the ratio or change the piston sizes.

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/19/17 10:33 a.m.
Keith Tanner said:

You need the pedal ratios, as noted. If they’re out of whack, you can either change the ratio or change the piston sizes.

What do you guys do for v8 swaps in a 99 miata?  It is the same htob used on t56 trans.

Dusterbd13
Dusterbd13 MegaDork
11/19/17 2:27 p.m.

Thats a really good question.  New vein of research!

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
11/19/17 3:19 p.m.

We use a wilwood master with an adapter to mate it to the Miata pedal. I forget what size, iirc it's bigger than factory. We've actually played with a couple of different sizes depending on whether the customer wants a light pedal or a short throw. 

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/19/17 3:20 p.m.

Are you able to research and find that out, keith?  I know at least 2 people that will thank you!

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
11/19/17 8:46 p.m.

I’m pretty sure our standard size for the NA/NB is 7/8”. 

 

Edit: Confirmed

DeadSkunk
DeadSkunk UberDork
11/20/17 7:36 a.m.

I helped a friend put a new clutch in his V8 Miata. It's an old 215 Buick, mated to a T5. He switched to a RAM htob from a Wilwood and we had problems. A 3/4 Wilwood master wouldn't disengage the clutch. He eventually had to get the 7/8 to move enough fluid and we still barely made the gap spec. 

Dusterbd13
Dusterbd13 MegaDork
11/21/17 5:13 p.m.

so, what do we use to go from a 7/8 wilwood master to the GM hydraulic throwout bearing? line wise. id love to hard line it all, but this throwout has some really funky E36 M3 going on that i havent taken the time to understand yet 

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
11/21/17 6:34 p.m.

We use braided lines with the appropriate ends on them.

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/21/17 9:42 p.m.
Dusterbd13 said:

so, what do we use to go from a 7/8 lowilwood master to the GM hydraulic throwout bearing? line wise. id love to hard line it all, but this throwout has some really funky E36 M3 going on that i havent taken the time to understand yet 

I posted the part number for the clutch fittings in my thread on the most recent page.  Use an an3 or 4 line and a Russell adapter for exactly this purpose.  I can't remember the other fitting off hand for the clutch master, but it is just a flared fitting to an3 or 4.

 

 

bmw88rider
bmw88rider GRM+ Memberand SuperDork
11/21/17 10:15 p.m.

If you need it, I think I've got some left over AN4 line that should be perfect for your application. Let me know if you are interested and I'll try to dig it out of the garage over the days off. 

Dusterbd13
Dusterbd13 MegaDork
11/22/17 5:47 a.m.

In reply to bmw88rider :

I will take you up on the offer. I have nothing that small, and with it being challenge....

 

Wv: im going to call you one of these days.  You are a very helpful resource and i feel i owe you a beer 

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/22/17 6:08 a.m.

Thanks!

 

I'm just excited that all the info I gathered is being used by somebody else.

Not too many Mazda swapped with gm 60 v6...

 

Btw, our chumpcar (the rx7 we put the gm 3400 in) is pretty damn fast on track.  The torque that thing makes will make you a bad driver.  Instead of hitting every apex and carrying every tiny morsel of momentum, you just put your foot down...

 

Do you have a gear and speed ratio spreadsheet for the miata yet?  I have one that has the fbody trans numbers if you need it.

bmw88rider
bmw88rider GRM+ Memberand SuperDork
11/22/17 6:18 a.m.

I'll dig out what I've got over the long weekend. Shoot me a PM with your address and I'll get it going your way. Nothing fancy. They are are the speedway motors house brand. 

Dusterbd13
Dusterbd13 MegaDork
11/22/17 7:31 a.m.

In reply to bmw88rider :

You have mail!

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/22/17 10:16 a.m.

The russell part number is 640281 for AN3 line.

 

I got AN3 line from speedway motors.

 

The master cylinder fitting "should be" this one....

I will need to check to see if I used a sealing washer...

wvumtnbkr
wvumtnbkr GRM+ Memberand UltraDork
11/22/17 10:19 a.m.

I have a spare hydraulic AN 3 line that i nicked the stainless outer mesh.  It still holds pressure, I just didnt want it in my endurance race car.  I can send that and the russell fitting (they give you two in a package).

I also have some gaskets, a new water pump, some other stuff.

I am notoriously bad at getting items shipped out, so it might be awhile.....

 

Shoot me an email with your address.

 

Rob R.

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