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Team 949 Racing @ NASA Nationals Sept 5-8, 2013

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Old 09-16-2013 | 10:49 PM
  #81  
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Originally Posted by speedengineer
I don't know all the specifics on your cars, but as far as I know:

-same dampers
-same sway bars (stock)
-same tires
-similar alignment
-different wheels...but small beans

Definitely the weight distribution plays a significant role as I was much at a much lower class weight. Didn't think it would results in such drastically different conclusions in spring rates though! I'm also wondering if your custom diff tuning has an effect?? Perhaps it just comes down to driving style and driver preference. I do prefer a fairly loose car -> understeer is the devil!
Loose is OK for one lap TT, awful for racing unless it Willow Springs. None of our drivers like a loose car. High entry speeds in a loose car means you're fighting turn in oversteer all the time. Miatas are fastest when they're trail braked which is not really possible with a loose car.

Our BGK set up is easily dialed in a results in a neutral car. By running the OEM sway bars which are more rear biased, we have to run more front spring bias. Pretty simple.

So yeah, without seeing your specific set up, I have no idea how you got 850/600 to work with Xidas and stock swaybars. Care to share the details I outlined? Otherwise I have no idea what the answer to your question is.
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Old 09-16-2013 | 10:59 PM
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I'm with Emilio on this one. Oversteer is fun and looks cool, but in a RWD car a little understeer gives you room to trail brake and get on the throttle earlier.
Old 09-16-2013 | 11:22 PM
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Originally Posted by emilio700
Loose is OK for one lap TT, awful for racing unless it Willow Springs. None of our drivers like a loose car. High entry speeds in a loose car means you're fighting turn in oversteer all the time. Miatas are fastest when they're trail braked which is not really possible with a loose car.

Our BGK set up is easily dialed in a results in a neutral car. By running the OEM sway bars which are more rear biased, we have to run more front spring bias. Pretty simple.

So yeah, without seeing your specific set up, I have no idea how you got 850/600 to work with Xidas and stock swaybars. Care to share the details I outlined? Otherwise I have no idea what the answer to your question is.
I hate to go OT, but I like reading this. I only have about 7-8 days between the Miata on way soft VMaxx/FM sway setup and a Yamaha R6.

So for the time being I have the typical "instructor line." So I wait very late, stand the car on its nose, turn in as hard and as fast as I can with just a touch of brake pressure left and I'm on back on the gas before the apex.

Anyone have tips for helping learn the proper Miata entrance beyond just "practice it." IE any tips for learning it more quickly?
Old 09-16-2013 | 11:23 PM
  #84  
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Originally Posted by emilio700
Loose is OK for one lap TT, awful for racing unless it Willow Springs. None of our drivers like a loose car. High entry speeds in a loose car means you're fighting turn in oversteer all the time. Miatas are fastest when they're trail braked which is not really possible with a loose car.

So yeah, without seeing your specific set up, I have no idea how you got 850/600 to work with Xidas and stock swaybars. Care to share the details I outlined? Otherwise I have no idea what the answer to your question is.
By saying 'I like a loose car' I didn't mean loose to the point where you'd ever have to lift in a high speed corner entry. Maybe an occasional need to slightly open the wheel up a little.

I'm happy to share:
850f 600r on Xida AST
Stock 99 sway bars
-3.4 deg camber front, max caster
-3.2 deg camber rear
Zero toe everywhere
About 4.5" ride height
205 R6 tires (SM6)
Min weight was 2190, post race weight was 2220ish. To get this, I didn't have any ballast in, so it was probably front heavy. When you run your cars at 2400, do you put the ballast in the trunk? Passenger side? Just wondering how different your front to rear weight bias might be.

Car got a little bit tail happy near the end of the nationals race, but that was because I overcooked the tires trying to catch the car in front of me who I 'thought' was actually in PTE and in the lead....doh!

Car wasn't loose at all this weekend at Autobahn Country Club, very hooked up.
Old 09-16-2013 | 11:24 PM
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Originally Posted by z31maniac
I hate to go OT, but I like reading this. I only have about 7-8 days between the Miata on way soft VMaxx/FM sway setup and a Yamaha R6.

So for the time being I have the typical "instructor line." So I wait very late, stand the car on its nose, turn in as hard and as fast as I can with just a touch of brake pressure left and I'm on back on the gas before the apex.

Anyone have tips for helping learn the proper Miata entrance beyond just "practice it." IE any tips for learning it more quickly?
1. Predictive lap timer
2. Scare yourself
3. Steer less
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Old 09-16-2013 | 11:32 PM
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Originally Posted by speedengineer
By saying 'I like a loose car' I didn't mean loose to the point where you'd ever have to lift in a high speed corner entry. Maybe an occasional need to slightly open the wheel up a little.

I'm happy to share:
850f 600r on Xida AST
Stock 99 sway bars
-3.4 deg camber front, max caster
-3.2 deg camber rear
Zero toe everywhere
About 4.5" ride height
205 R6 tires (SM6)
Min weight was 2190, post race weight was 2220ish. To get this, I didn't have any ballast in, so it was probably front heavy. When you run your cars at 2400, do you put the ballast in the trunk? Passenger side? Just wondering how different your front to rear weight bias might be.

Car got a little bit tail happy near the end of the nationals race, but that was because I overcooked the tires trying to catch the car in front of me who I 'thought' was actually in PTE and in the lead....doh!
Ballast in passenger floor, as close to centerpoint of axle centerlines as possible. Lowest PMI and CG possible. We experimented putting ballast in the trunk. Yeah, that didn't work.

Still dunno about your set up. If we had ran those springs, our cars would have been slower and a lot easier to spin.

We found no combo with stock bars that allowed 500 rear springs without being overly sensitive to lift throttle. The 1000 fronts were chose simply because they're at bout the limit of what OTS Xidas can handle at 1.7G in a 2400lb car. We had a few clicks left up front so 1100 or 1200's might have been possible but the 100's already made it tricky to drive. With 800/500 and big bars or especially 700/400, it's very docile and still super fast. The 1000/400 and 1000/450 setups gave us about the same balance as our standard 800/500 with 54107/14mm bars.


Oh and, "You're welcome" for the assistance at Miller
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Old 09-16-2013 | 11:45 PM
  #87  
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Originally Posted by emilio700
Ballast in passenger floor, as close to centerpoint of axle centerlines as possible. Lowest PMI and CG possible. We experimented putting ballast in the trunk. Yeah, that didn't work.

Still dunno about your set up. If we had ran those springs, our cars would have been slower and a lot easier to spin.

We found no combo with stock bars that allowed 500 rear springs without being overly sensitive to lift throttle. The 1000 fronts were chose simply because they're at bout the limit of what OTS Xidas can handle at 1.7G in a 2400lb car. We had a few clicks left up front so 1100 or 1200's might have been possible but the 100's already made it tricky to drive. With 800/500 and big bars or especially 700/400, it's very docile and still super fast. The 1000/400 and 1000/450 setups gave us about the same balance as our standard 800/500 with 54107/14mm bars.


Oh and, "You're welcome" for the assistance at Miller
Hmm, interesting. The only other thing that I can think of would be that I have a slightly larger scrub radius than you do (I run ISC bushings, and then 20mm offset wheels to clear). I'm sure you're familiar with the cross weight change due to turning the steering wheel - castor and kingpin angles in combination with scrub radius and mechanical trail result in one wheel lifting and the other extending, thus changing the cross weight/jacking on the car while in corners. However, a larger scrub radius would technically result in a cross weight change that Adds front grip, so perhaps that isn't the answer, unless it has some other effect that I'm not accounting for.

Haha, yes, thanks for the tips on the optimal track line Friday night! I'm sure William was very happy with you
Old 09-17-2013 | 01:13 AM
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Thanks for sharing. I 'watched' your battle on Race Monitor from start to finish so it was fun to see the video. I'm surprised Andrew's Green Hornet smoke screen countermeasures didn't put you off.
Old 09-17-2013 | 02:13 AM
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Originally Posted by mr_hyde
Thanks for sharing. I 'watched' your battle on Race Monitor from start to finish so it was fun to see the video. I'm surprised Andrew's Green Hornet smoke screen countermeasures didn't put you off.
Andrew drove a great race considering he had one hand on the fire pull the whole time. Damn shame the cali PTE crew came unglued. We had the fastest cars by a comfortable margin but broke.
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Old 09-17-2013 | 02:49 AM
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He was clearly down on power by the end. It looked like a massive leak burning off as it hit the pipe on hard right handers. What was the cause?
Old 09-17-2013 | 10:40 AM
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Originally Posted by mr_hyde
He was clearly down on power by the end. It looked like a massive leak burning off as it hit the pipe on hard right handers. What was the cause?
Andrew smoke-em ***** pipe.
Old 09-17-2013 | 02:14 PM
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Originally Posted by emilio700
Loose is OK for one lap TT, awful for racing unless it Willow Springs. None of our drivers like a loose car.
Interesting... based on the race alignment numbers on your site I always just assumed that you guys liked loose race cars. I guess you just try and keep toe at 0 for rolling resistance and then adjust balance with springs/bars/shocks?

My car had full SM suspension when I bought it and my preferred alignment shop works primarily on SMs, so I just started with their standard SM alignment, which was 0 toe front and around 1/16 rear. They preferred very little toe for both low rolling resistance and to keep the car loose. I slowly started adding more rear toe to make the car easier to drive consistently, and my current setup is 700/400, stock 91 bars, 0 front toe, and 3/32-1/8" total rear toe in. It's a little more rear toe than I'd prefer, but the car is so easy to drive right now that I've been focusing $$ and time elsewhere.
Old 09-17-2013 | 02:58 PM
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Lean is mean
Loose is fast
I'm homo
Old 09-17-2013 | 08:58 PM
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Originally Posted by hustler
Lean is mean
Loose is fast
I'm homo
1:58pm is a bit early to be that sauced. Lucky...
Old 09-17-2013 | 09:06 PM
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Originally Posted by jpreston
my current setup is 700/400, stock 91 bars, 0 front toe, and 3/32-1/8" total rear toe in. It's a little more rear toe than I'd prefer, but the car is so easy to drive right now that I've been focusing $$ and time elsewhere.
You're basically using the rear toe as a crutch to cure the oversteer induced by not having a front sway or more front spring. 1/8" rear toe in is what I run on Theseus.
Old 09-17-2013 | 09:54 PM
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Originally Posted by jpreston
Interesting... based on the race alignment numbers on your site I always just assumed that you guys liked loose race cars. I guess you just try and keep toe at 0 for rolling resistance and then adjust balance with springs/bars/shocks?

My car had full SM suspension when I bought it and my preferred alignment shop works primarily on SMs, so I just started with their standard SM alignment, which was 0 toe front and around 1/16 rear. They preferred very little toe for both low rolling resistance and to keep the car loose. I slowly started adding more rear toe to make the car easier to drive consistently, and my current setup is 700/400, stock 91 bars, 0 front toe, and 3/32-1/8" total rear toe in. It's a little more rear toe than I'd prefer, but the car is so easy to drive right now that I've been focusing $$ and time elsewhere.
your setup is looser than the either of the suggestions on 949 site. At least in my spreadsheet you a few notches below, not nearly as bad as the 850/650 setup listed above though. Not sure if you can use NB sway bars on an NA, but a 22-23mm front sway should set you pretty close to the 949 numbers. Or just get the RB/mazdaspeed setup.

Not considering alignment in this of course.
Old 09-18-2013 | 04:44 AM
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Originally Posted by Track
your setup is looser than the either of the suggestions on 949 site. At least in my spreadsheet you a few notches below, not nearly as bad as the 850/650 setup listed above though. Not sure if you can use NB sway bars on an NA, but a 22-23mm front sway should set you pretty close to the 949 numbers. Or just get the RB/mazdaspeed setup.

Not considering alignment in this of course.
Makes sense... the last time I read farther into that page than just glancing at the alignment numbers was 2-3 years ago when I bought the car. I forgot about the rest of the setup notes. Definitely makes sense now with the suggestion for a 1" or bigger front bar.

I'd like to try a different bar but my car is built solely for nasa TT/PT. I'm keeping the stock bars for points reasons. If I do anything I'll try a stiffer front spring like sav mentioned, but I don't have any complaints about the current setup.
Old 09-21-2013 | 02:18 AM
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HOLY crap!

Sonnys car is unreal fast! Blowing by a C car on the straightaway though? hmm... looks a little too fast...
Old 09-21-2013 | 02:36 AM
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Originally Posted by circuitmstr74
HOLY crap!

Sonnys car is unreal fast! Blowing by a C car on the straightaway though? hmm... looks a little too fast...
Are you implying that we cheat?
I am so tired of this **. Sorry if that freaks you out but you are the wrong person with the wrong throw away comment at the wrong time.

It was the slowest D in straight line. Watch his in car video from the races. Started on pole, gets walked by every other D at the start and ends up last going into T1. Works his way through on the backside of the course under braking and in the turns.

NASA dyno'd it and sealed the ECU. We made 159whp. Our limit was 167whp which we were unable to make (we tried). NASA had my team tear the motor down while everyone else was going home Sunday. Whistler, everything. Of course there was nothing to find. Who protested us? A local "friend" from Socal who's engine I detuned after he blew the dyno at the last SoCal race.

You want to question our methods, read the thread. Every detail of our E and D cars are spelled out. Setup and drive as well as our team does, then you can be skeptical.
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Last edited by emilio700; 09-21-2013 at 04:37 AM.
Old 09-21-2013 | 02:43 AM
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Originally Posted by circuitmstr74
Sonnys car is unreal fast! Blowing by a C car on the straightaway though? hmm... looks a little too fast...
The Honda points him by at ~25 seconds. It's a TT, not a class race and the Honda driver was smart enough to know he was slower around even though he would win a drag race.



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