Front subframe underbody brace

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jerrah
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Front subframe underbody brace

Postby jerrah » Tue Feb 22, 2011 11:20 am

I believe later model cars have this standard but my NA6 didn't...

I was a bit skeptical that sticking a steel bar with crushed ends on the bottom of my front subframe would make much of a difference but wow...

Much less twisting coming out of the driveway. Car doesn't feel like it's trying to throw the hardtop off the car. Driving down the street the car is so much quieter and stable through bends. I haven't particularly pushed the car but I was just surprised by how noticeable the change was!
1991 MX5

Smithy
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Re: Front subframe underbody brace

Postby Smithy » Tue Feb 22, 2011 3:20 pm

Rather than start a new thread I thought I'd post here due to relevance.

I need to look into this myself, and if someone can confirm this the first run of NA6 (ie my 1989), do not have threaded hole on that bracket for this brace to fix... as such bolts need to be dropped in from the top side (same as later models?).... although the squeeze is particularly tight with the lower control arm and bushing there (?did I name the part correclty?). Is this lack of space same on later models... ?
I have some material to use as bracing here but only concern is being able to get a open ended spanner or somethi in the space there to hold bolt whilst nuts tighted under it...

Also I' have my eye on a RacingBeat brace for this space which comes with a plate to slide into this location for the bolts to bolt up from underneath... any NA6 owners have experaince with this...? ie managin to fit this threaded plate into this tight little gap ?

(whilst im in California/Nevada in April I hope to pick up a carry on luggage size goodie or too and this seems reasonable priced as we can drop into their store...)

cheers.
old rides:
56 Morris Minor Pickup -58 Morris Minor Sedan -86Honda CityTURBO II
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jerrah
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Re: Front subframe underbody brace

Postby jerrah » Tue Feb 22, 2011 3:43 pm

I dropped a bolt down through the top. Whilst it's tight I managed to do it this morning even with my huge hands before work this morning. I found I needed one arm in through the suspension arm and my little finger poking through the hole next to it to get the bolt through with a washer under it. A standard 17mm spanner fitted fine in through the side to tighten it up.

A threaded plate on the top would be certainly easier but I'm hoping I don't need to take the brace on and off very often.
1991 MX5

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CheyneX5
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Re: Front subframe underbody brace

Postby CheyneX5 » Tue Feb 22, 2011 11:43 pm

I'll add my 2c.

I have had 2 NA6's in the past few years and have dríven various others. Some have had bracing and some have not. I have settled for the Cusco Tension Braces. Some may say that they cost too much, or that they look to fancy, but they do an incredible job at tying the car together. It makes a world of difference and really grabs on tight.

The front is a four point which mounts with the small threaded square plates. The rear mounts on the back of the subframe.

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BadBong
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Re: Front subframe underbody brace

Postby BadBong » Tue Feb 22, 2011 11:52 pm

What's the difference between these and the FM butterfly brace from the perspective of the end result?

Isn't it cheaper to get the FM brace instead?

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CheyneX5
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Re: Front subframe underbody brace

Postby CheyneX5 » Wed Feb 23, 2011 12:06 am

These tighten up the car at either end and bolt to the subframe. This adds a more solid feeling when cornering and day to day driving.

The Butterfly Brace will tighten the centre of the car and bolt to the chassis. This will tie the 2 ends of the car together, making it more solid and making it flex a lot less.

Have both and you have one stiff car.
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Re: Front subframe underbody brace

Postby BadBong » Wed Feb 23, 2011 12:12 am

Thx mate.

I've read from other people's thread that the FM brace actually made it more comfortable to drive (plus the elimination of the shutter at high speed).

Do these under body braces have adverse effect on ride quality? (If i make it any bumpier my partner might get :evil: )

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CheyneX5
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Front subframe underbody brace

Postby CheyneX5 » Wed Feb 23, 2011 12:25 am

The butterfly brace will most certainly get rid of a lot of the scuttle and shake.

The braces do not make the ride any harsher, not in my opinion anyway. The most noticeable difference was in cornering, the car felt a lot more solid. Less body flex/roll. Turning became very sharp with out being too over the top.

I have paired these braces with FM adjustable sway bars and Whiteline adjustable end links and the car feels literally like a go kart. Stiff as a rock.
90' NA6 - Classic Red
09' Skoda Octavia vRS TSi Wagon - Race Blue

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jerrah
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Re: Front subframe underbody brace

Postby jerrah » Wed Feb 23, 2011 1:18 am

That front Cusco brace looks interesting. Where did you get it from / how much? I have a NA8 rear end in my car with all the stock assorted bracing and Torsen.

I'm not sure if it would provide much over my steel pipe though which provides good bang for buck. 8)
1991 MX5

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Re: Front subframe underbody brace

Postby CheyneX5 » Wed Feb 23, 2011 10:34 am

If your going from a 2 point tubular brace to something like the Cusco unit, the difference will be apparent but not as obivious as putting it on with no previous comparison. After all, the cusco unit has four mounting points rather than 2. It will do more. This being said, i'm sure that having a 4 point on the rear like a few of the guys here would do more, but i was picking and wanted a matching pair.

The Cusco stuff is not cheap, the front brace can vary between $250 - $350. The rear $100 - $250. This being said though, your paying for quality here, they are made from a high tensile Aluminium conpound and the welds are mind blowing. They are also incredibally light, easily balanced on my pinky.

I bought mine from The MX5 Factory as they are suppliers of certain Cusco parts.

As you mentioned, you have an NA8 rear end, the rear brace will be slightly different. Very similar look though. The NA6 model, as pictured above, will mount to the face of the subframe and has a slight curve on either end. The NA8 model is a flat piece which mounts from underneath.
90' NA6 - Classic Red
09' Skoda Octavia vRS TSi Wagon - Race Blue

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jerrah
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Re: Front subframe underbody brace

Postby jerrah » Wed Feb 23, 2011 5:21 pm

The NA8 brace I have on the rear is a 4 point already. For the price I think at this stage I'll just stick with my two point steel brace, it's cheap and seems to do the job. I can't see the bling from the drivers seat. :)

(Not doubting the quality but I'm not sure if I can justify it)
1991 MX5


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ForceMajeure
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Re: Front subframe underbody brace

Postby ForceMajeure » Thu Feb 24, 2011 1:03 am


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jerrah
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Re: Front subframe underbody brace

Postby jerrah » Thu Feb 24, 2011 9:18 am

Wow that front brace is such an obvious knock-off of the Cusco.

I've been impressed each day driving to work just how tight the car feels!
1991 MX5

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Re: Front subframe underbody brace

Postby BadBong » Thu Feb 24, 2011 9:22 am

Has anyone used these 'knock offs'? I assume the strength would be the same but perhaps it'll be heavier?

I've only looked at these cause i don't know how much the cusco ones are and where to source them... does anyone know?

ForceMajeure - let's chat about sharing the shipping costs :)


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