QUICK QUESTION! NB8A gearbox to NA8!

Engines, Transmissions & Final Drive questions and answers

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Li7hium
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QUICK QUESTION! NB8A gearbox to NA8!

Postby Li7hium » Thu May 15, 2008 12:21 pm

Hey guys,

Have to get a new (second hand) gearbox for Lara.

So three questions:

1. Is the NB8A gearbox stronger than the NA8?

2. Does the NB8A gearbox have the same ratio gears at the NA8?

3. Will a NB8A gearbox marry up to a NA8 engine and driveshaft without modification?

Urgent responses required!

Much thanks!

Matt
NA8
Wakefield 1:14:78 28-6-09! Oran Park GP 1:27:73 30-03-08 Oran Park South 54:50 14-10-2007 Eastern Creek 2:02:44 6-8-07
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Postby Steampunk » Thu May 15, 2008 1:07 pm

How urgent is urgent?
Try calling Richard from MX5PLus: Ph (07) 3356 9457, but this may be the shop's number (only open Saturdays) but I think he checks his messages frequently.

Zoomzoom has fitted a 6-speed into his NA6 if that is any help.
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Li7hium
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Postby Li7hium » Thu May 15, 2008 1:10 pm

Thanks mate.

Can't be a 6spd. As a 6 spd g/box was not an option with my car, and the ratios are different, if I put a 6 spd box in the car, it would throw me out of Type 2 Class for Supersprinting. I don't want that.

I have to tell the mechanic today what gearbox to source. :frown:

Matt
NA8
Wakefield 1:14:78 28-6-09! Oran Park GP 1:27:73 30-03-08 Oran Park South 54:50 14-10-2007 Eastern Creek 2:02:44 6-8-07
BRZ
Pheasant Wood 1:05.4940
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Rotary
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Postby Rotary » Thu May 15, 2008 2:35 pm

answer to Q2

Yes ratios are identical

other questions, not sure,

I Know NB has a brace from box to diff

If the NA has that too, I would say their identical, otherwise thats prob the main difference
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Postby RG.net » Thu May 15, 2008 3:26 pm

the only thing mazda didnt change in the 2nd gen mx-5 from the first is the gearbox, they are identical
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Boags
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Re: QUICK QUESTION! NB8A gearbox to NA8!

Postby Boags » Thu May 15, 2008 3:49 pm

Li7hium wrote:1. Is the NB8A gearbox stronger than the NA8?

2. Does the NB8A gearbox have the same ratio gears at the NA8?

3. Will a NB8A gearbox marry up to a NA8 engine and driveshaft without modification?


1. No.

2. Yes.

3. Yes.

:D
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Li7hium
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Postby Li7hium » Thu May 15, 2008 4:04 pm

Thanks Boags.

FWIW, I have seen a cheap Grace Green NB8B on eBay that is dying to be turbo'ed!

So, not stronger, just newer. Oh well.

Matt
NA8
Wakefield 1:14:78 28-6-09! Oran Park GP 1:27:73 30-03-08 Oran Park South 54:50 14-10-2007 Eastern Creek 2:02:44 6-8-07
BRZ
Pheasant Wood 1:05.4940
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Postby Boags » Thu May 15, 2008 4:19 pm

It's an NB8A... :frown:

There's a nice looking Blue one though. Might have to make a call... 8)
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Li7hium
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Postby Li7hium » Thu May 15, 2008 4:27 pm

That's not Bevan's car is it? The blue one that is.
NA8
Wakefield 1:14:78 28-6-09! Oran Park GP 1:27:73 30-03-08 Oran Park South 54:50 14-10-2007 Eastern Creek 2:02:44 6-8-07
BRZ
Pheasant Wood 1:05.4940
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Re:

Postby Boags » Thu May 15, 2008 11:26 pm

Li7hium wrote:That's not Bevan's car is it? The blue one that is.


No, I don't think so; Bevan was asking drug money for his... :mrgreen: :lol: :P
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Li7hium
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Postby Li7hium » Fri May 16, 2008 10:38 am

OK, here is the difficult question.

Is there an easy way to distinguish between the NA6, NA8 and NB8A gearbox?

Local second hand parts mob can't find any markings on any of them to tell one from the other.

Matt
NA8
Wakefield 1:14:78 28-6-09! Oran Park GP 1:27:73 30-03-08 Oran Park South 54:50 14-10-2007 Eastern Creek 2:02:44 6-8-07
BRZ
Pheasant Wood 1:05.4940
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Spranga
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Re:

Postby Spranga » Fri May 16, 2008 6:19 pm

carsokay wrote:If they have left the speedometer drive gear unit (speed sensor) in the box, the NB ones should have an electrical sensor as opposed to a mechanical one on the NAs.


Will this cause problems with your speedo?
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