Chassis stiffening - which parts are good?
#65
If you check the fast autocross Miatas going to nationals you'll see them being stripped of all possible bracing. Reason is the weight saved by removing any of those braces is better for cornering than the minor stiffening effects the braces add.
If you want your car be a good street cruiser - the braces are good for their effects on NVH. But not if it is a dedicated racer ...
If you want your car be a good street cruiser - the braces are good for their effects on NVH. But not if it is a dedicated racer ...
#66
If you check the fast autocross Miatas going to nationals you'll see them being stripped of all possible bracing. Reason is the weight saved by removing any of those braces is better for cornering than the minor stiffening effects the braces add.
If you want your car be a good street cruiser - the braces are good for their effects on NVH. But not if it is a dedicated racer ...
If you want your car be a good street cruiser - the braces are good for their effects on NVH. But not if it is a dedicated racer ...
#67
I.e. talk with any CSP national champ in a Miata and you'll see their cars stripped of all bracing possible allowed by the UD/BD rules. Those guys have tested bracing vs no bracing against the clock many many times.
I just read few days ago that Bill even recently removed the flex section from his current header because of weight savings ... that's how serious those guys are ...
#70
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At first I wasn't sure, but I can see how that would be likely. All of those factory braces do probably add up to 40-50lbs, and probably don't have all that much effect on the track. However, for a street driven car, or a car making considerably more power than stock, I would want the bracing. Whats 40lbs when you make 100hp+ over stock. Plus most of the bracing is around the same height as the wheels, so its not making the car top heavier.
#71
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I don't race often enough to make the Miata even less DD friendly. My mother visited a few weeks ago and commented that I'd "taken a perfectly good car that I (she) liked to drive and ruined it". I need to get some current good pics of Andrew's car so I can show her how much restraint I've shown in the pursuit of speed.
#72
Those 100hp+ don't help in the middle of a corner.
And the 40lbs hurt your grip.
Then on a straight do you think a 20 lbs ladder brace would help your 100hp+ over car accelerate quicker?
The CSP Miata national level prepped cars are much more violent on the hardware too ... they have less than 200 hp but they break PPF, differential cases, etc. often, generate over 1.5G in cornes and are driven much harder than 99.9% of the turbo Miatas on this forum. When sitting in those Miatas in the middle of a run it feels like they are going to fall apart any moment. And owners have found that all these bolt on braces still hurt times ...
For a street driven car I agree. One doesn't want his car to feel like it is going to fall apart when driving over a railroad crossing
All I was saying that while making our cars feel more comfortable or help other parts last longer, they don't help with getting faster lap times as many who only test by feel try to convince you
And the 40lbs hurt your grip.
Then on a straight do you think a 20 lbs ladder brace would help your 100hp+ over car accelerate quicker?
The CSP Miata national level prepped cars are much more violent on the hardware too ... they have less than 200 hp but they break PPF, differential cases, etc. often, generate over 1.5G in cornes and are driven much harder than 99.9% of the turbo Miatas on this forum. When sitting in those Miatas in the middle of a run it feels like they are going to fall apart any moment. And owners have found that all these bolt on braces still hurt times ...
For a street driven car I agree. One doesn't want his car to feel like it is going to fall apart when driving over a railroad crossing
All I was saying that while making our cars feel more comfortable or help other parts last longer, they don't help with getting faster lap times as many who only test by feel try to convince you
Last edited by j_man; 08-26-2009 at 02:46 PM.
#73
j-man, I don't think he was talking about auto-x necessarily. I would argue that riding in an LS1 Miata at Laguna Seca convinced me that it was worth it to have as much bracing and heavy BBK as possible.
koto, I totally feel your pain. I get criticism from the fam all the time for 'ruining a perfectly good car'.
koto, I totally feel your pain. I get criticism from the fam all the time for 'ruining a perfectly good car'.
#75
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I for one would want a really solid feel to the car while doing 100+ MPH through Turn 1 at TWS
Spec Miata also runs a full cage (right?), which street cars do not, so that in itself would add a lot of chassis bracing.
Spec Miata also runs a full cage (right?), which street cars do not, so that in itself would add a lot of chassis bracing.
#77
About the track case - it is all up in the air unless someone of national caliber at a test day does a bunch of laps with bracing then without, then with, then without again and then analyzes the data from the logger ...
Last edited by j_man; 08-26-2009 at 04:22 PM.
#78
AFAIK they can install such (IIRC safety rules allow it) but they don't because the Miata gets slower ...
At autocross you will see Miata with a cage only if the class rules mandate it or if the owner decided to do it for safety. The weight it adds slows the car down ...
The track case most likely will turn out the same way, but very fast & powerful Miata without a cage starts shifting towards the driver life/death gamble zone
Throwing extra metal/weight on a Miata trying to make it stiffer is a totally different thing. If you get rid of the unibody and replace it with some space frame both stiffer and without weight penaltry ... sure.
Last edited by j_man; 08-26-2009 at 04:21 PM.
#79
EDIT:
We have guy locally that has sent a bunch of money lightening his camaro for autox. The funny thing is, he is built almost exactly like my av.