Jump to content

Photo

NA vs. NB subframe bracing

- - - - -

Best Answer davew , 05-17-2017 10:22 AM

The NB brace does not fit on an NA subframe and vice versa. So unless you allow subframe upgrades, you can not swap the braces. 

 

NA stays on an NA car

NB stays on an NB car

Go to the full post »


  • Please log in to reply
32 replies to this topic

#21
Brandon

Brandon

    Veteran Member

  • Members
  • PipPipPipPipPip
  • 718 posts
  • Location:North Jersey
  • Region:NNJR
  • Car Year:1996
  • Car Number:48SM

To my mind, and I'm not being a rules whore in this case, but if you have an NA6 and install an NA8 subframe (they are interchangeable), this would not be a non-compliant configuration.

Unlike a NB subframe in an NA, which requires the new rack and provides better suspension geometry, the improvements would probably be negligible.

Still, I'd be curious to know whether there's an improvement in lateral stability of the rear pick-up point of the LCA with that bracket between those mount points.

 

Would it be grounds for a potential protest? Perhaps, but then I"d say you'd have a case for an error/omission similar to the rear subframe bits (like what Dave W. references is missing in the GCR).

At this point in the rules progression, I'd say write a letter to the CRB asking for a rules clarification about both the front and rear subframes.


Bona fide - A bonafide Spec Miata driver

#22
Ron Alan

Ron Alan

    Veteran Member

  • Members
  • PipPipPipPipPip
  • 3,570 posts
  • Location:Northern CA
  • Car Year:1995

I just put a front bar on a 1.6 car...I had the bar laying around and the capture bolts were in the subframe! Champ car and I have no idea if the front subrame was original! But I have seen people slide in capture nuts and put on the oem bar...the hole is in the correct place if the nuts aren't already there. Spend time working on your car Alberto and stop typing :) You have a good local source a text away!!


  • Team Nitro likes this

Ron

RAmotorsports

2014 NASA SM Western States Champion(Car owner)

2015 NASA 25HR E3 Champion(Car owner)

2016 NASA 25HR E3 Champion(Car owner)

2017 NASA 25HR E3 Champion(Car owner)

2018 NASA 25HR E3 Champion(Car owner)

2017 NASA NORCAL SM Series Leader

2018 NASA NORCAL SM Series Leader

Donor - Made PayPal donation Bona fide - A bonafide Spec Miata driver

#23
Alberto

Alberto

    Veteran Member

  • Members
  • PipPipPipPipPip
  • 1,281 posts
  • Location:Mountain View, CA
  • Region:SFR
  • Car Year:1990

To my mind, and I'm not being a rules whore in this case, but if you have an NA6 and install an NA8 subframe (they are interchangeable), this would not be a non-compliant configuration.

Unlike a NB subframe in an NA, which requires the new rack and provides better suspension geometry, the improvements would probably be negligible.

Still, I'd be curious to know whether there's an improvement in lateral stability of the rear pick-up point of the LCA with that bracket between those mount points.

 

Would it be grounds for a potential protest? Perhaps, but then I"d say you'd have a case for an error/omission similar to the rear subframe bits (like what Dave W. references is missing in the GCR).

At this point in the rules progression, I'd say write a letter to the CRB asking for a rules clarification about both the front and rear subframes.

 

I don't see how.  The clause in the rule as stated clearly allows it and has for decades.  Doesn't make sense to allow the rear bracing from the 1997 to be added but not the front.

 

The improvement is slight but I like the way the car feels better with the brace.

 

 

 

I just put a front bar on a 1.6 car...I had the bar laying around and the capture bolts were in the subframe! Champ car and I have no idea if the front subrame was original! But I have seen people slide in capture nuts and put on the oem bar...the hole is in the correct place if the nuts aren't already there. Spend time working on your car Alberto and stop typing  :) You have a good local source a text away!!

 

 

I am working on my car!  That's how I come up with these questions :)

If the captive nuts are there; it's a 1.8 subframe.  None of the 1.6 subframes have the captive nuts.  There are holes in the subframe area where the rear section of the LCA attach (the one that controls caster) where you can attach an aftermarket brace.  


Bona fide - A bonafide Spec Miata driver

#24
Steve Scheifler

Steve Scheifler

    member

  • Members
  • PipPipPipPipPip
  • 2,256 posts
  • Location:St. Louis
I can see how you read the rules to include the front, but the wording then continues on to state that a kit is available from Mazda. The only kit I found was for the rear which includes all the weld-on tabs etc. Do they offer a kit for the front?
Bona fide - A bonafide Spec Miata driver

#25
Steve Scheifler

Steve Scheifler

    member

  • Members
  • PipPipPipPipPip
  • 2,256 posts
  • Location:St. Louis

Here's a nice article with pics of how it's done:
https://5xracing.com...miataparts.html

They make it WAY more difficult than it needs to be. For the front mounts just drill the hole from the bottom large enough for the nut (with welds) to pass through it, then weld the tab to the bottom of the car.
Bona fide - A bonafide Spec Miata driver

#26
Steve Scheifler

Steve Scheifler

    member

  • Members
  • PipPipPipPipPip
  • 2,256 posts
  • Location:St. Louis
Deleted.
Bona fide - A bonafide Spec Miata driver

#27
Alberto

Alberto

    Veteran Member

  • Members
  • PipPipPipPipPip
  • 1,281 posts
  • Location:Mountain View, CA
  • Region:SFR
  • Car Year:1990


I can see how you read the rules to include the front, but the wording then continues on to state that a kit is available from Mazda. The only kit I found was for the rear which includes all the weld-on tabs etc. Do they offer a kit for the front?

 

Yes.  Here's the part number:

48822156988_b65368654f.jpgspec miata front subframe bracing by alberto_mg, on Flickr


Bona fide - A bonafide Spec Miata driver

#28
Brandon

Brandon

    Veteran Member

  • Members
  • PipPipPipPipPip
  • 718 posts
  • Location:North Jersey
  • Region:NNJR
  • Car Year:1996
  • Car Number:48SM

Alberto, those braces (gussets) are the ones that are welded to the LCA front mount point to prevent subframe tearing.

These are different from what you're looking for.


  • Steve Scheifler likes this
Bona fide - A bonafide Spec Miata driver

#29
Alberto

Alberto

    Veteran Member

  • Members
  • PipPipPipPipPip
  • 1,281 posts
  • Location:Mountain View, CA
  • Region:SFR
  • Car Year:1990

Sigh...  Thanks.

I'll call Mazda again and hopefully get through to them...  

fwiw, I spoke with AWR and he remembers creating the rear retrofit parts but not the front.


Bona fide - A bonafide Spec Miata driver

#30
Steve Scheifler

Steve Scheifler

    member

  • Members
  • PipPipPipPipPip
  • 2,256 posts
  • Location:St. Louis
Let us know because I’m pretty certain nothing has ever been offered for the front. That said, the plural “braces” combined with the reference to the ‘97 configuration and the lack of the word “rear” seems arguably clear despite the fact that the referenced kit has never included the front. Funny/embarrassing, I’ve never questioned it before and simply installed what we were sold.

BTW, regarding the rear, for many years now the original 1.6 has been discontinued and superceded by the NA 1.8 version which comes with the tabs installed.
Bona fide - A bonafide Spec Miata driver

#31
Alberto

Alberto

    Veteran Member

  • Members
  • PipPipPipPipPip
  • 1,281 posts
  • Location:Mountain View, CA
  • Region:SFR
  • Car Year:1990

Will do.  For years, I thought there was a front kit based on the wording.  I just never bothered to order it since the front subframe was bent on my car when I took delivery and I just swapped directly to a used 1.8 subframe b/c it was easily available nearby and cheap.  

Thanks.


Bona fide - A bonafide Spec Miata driver

#32
Rick Worth

Rick Worth

    Member

  • Members
  • PipPipPip
  • 18 posts
  • Location:Tennessee
  • Region:Mid-South
  • Car Year:1999
  • Car Number:24

Let us know because I’m pretty certain nothing has ever been offered for the front. That said, the plural “braces” combined with the reference to the ‘97 configuration and the lack of the word “rear” seems arguably clear despite the fact that the referenced kit has never included the front. Funny/embarrassing, I’ve never questioned it before and simply installed what we were sold.

BTW, regarding the rear, for many years now the original 1.6 has been discontinued and superceded by the NA 1.8 version which comes with the tabs installed.

How about these Steve? I bought a set of these last year and never welded them on. They are from Mazdaspeed for the NA/NB front subframe. 

 

0000-04-5989 Mazda

 

https://mazdaracers....a-in-scca-nasa/

 

https://www.google.c...7TlGoCdM:&vet=1



#33
Steve Scheifler

Steve Scheifler

    member

  • Members
  • PipPipPipPipPip
  • 2,256 posts
  • Location:St. Louis
Those are the reinforcement gussets, developed by Dave Wheeler (iirc) and approved just in the past couple years for all cars. Nothing to do with original bolt-on braces from 97 forward discussed here.
Bona fide - A bonafide Spec Miata driver




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users