Classing my Turbo Miata in TTB, but it looks like TTS

[hustler]

My car is a mutant and I'm not sure which sections apply to my car, it's swap, and it's weight. However, it's a modest 240whp car I drive to work once or twice per month and drive to and from the track.

 

It was a 1991 Miata, now it has a turbo and an engine from a 99 Miata, here's the problem:

 

Section 6.1.2:

2460lb/242 = 10.16 ~TTB; or 2460/232 = 10.60 ~TTB, or 2460/275 = 8.9 ~TTA

Let's go with 10.6 lb/hp

Section 6.2.5

+.8 for 245 or smaller DOT Tire = 11.2

-.35 for weight under 2550 = 10.85

TTB looks safe until I add the points.

 

Section 6.4.1 Upclassing (assuming TTB)

(3) +7 for R-comp tire = 7

(5) -10 for skinny tires = -3

+8 for increased displacement (1.6-1.8 swap w/ bore) = 5

+10 for aftermarket computer = 15

+1 for modded oem air box (now turbo) = 16

+7 for aftermarket intercooler = 23

+2 modification of header (now there's a turbo) = 25

+1 removal of cat converter = 26

+2 non-oem exhaust = 28

+3 upgraded # of forward gears (Miata 6-speed) = 31

+3 modified LSD (late model Miata) = 34

+3 non-oem shocks = 37

+2 non oem front sway = 39

+2 non oem rear sway = 41

+2 upgraded outer tie rod ends (OEM update) = 43

+2 non-oem brake caliper = 45

+3 new bumper = 48

+4 roll bar = 52

 

52 Points put's me up 2 groups from B to S, is this accurate? I don't think this is a TTS car. I think it's on the high end of TTB, low end of the TTA group.

[boomn29]

Since you've added forced induction to a car, you'll need to have it reclassified by dyno/weight.

 

Lots of people do this. You need to put together an email with your car's dyno whp and estimated weight and submit to Greg G for a new base class. Or you can ask for a specific base class and give him either the whp or weight and he'll give you the last.

 

Once you have your reclass, you don't need to take any pts for power mods on the car. Just add in tires, suspension, aero, etc and done!

 

Check out the sticky above: viewtopic.php?f=2&t=12638

[drivinhardz06]

Since you've added forced induction to a car, you'll need to have it reclassified by dyno/weight.

 

FI miata, TTE right?

[kbrew8991]

It looks funny because you're doing it wrong I suspect it will end up a TTB car.

 

Since you're in an aftermarket forced induction car you need to read Engine/Drivetrain #3 if reading 2010 TT rules, or C3 if reading 2011 PT rules (TT will be the same car-classing wise). Send in your RWHP and desired minimum competition weight with driver, etc to the National Director for your new base class for your car. It'll get run through the classification process as if it were a brand-new car.

 

Then once you have that back you take no points for power stuff, but you take points for all the the other sections and THEN you can figure out your final class. If I had to guess (and this is 100% unofficial, just a guess) I suspect you'd end up TTB or TTB* base class, so lets work through it assuming that

 

TTB* base class via reclassification by the Natl Director

+7 for asterix (if its TTB*, 0 if TTB of course)

 

+0 for your power parts since you've been reclassified, but you must always dyno at or under what you sent in. Give yourself a bit of a buffer, and note that SAE correction will be used.

 

-10 pts for 225s when your base class is TTB/265 width. (note this is tied to your base class, not final competition class)

 

+7 for tire compound

 

+3 for transmission swap to the 6 speed

 

+3 for the LSD

 

+3 non-oem shocks

 

+2 non oem front sway

 

+2 non oem rear sway

 

+2 upgraded outer tie rod ends (OEM update)

 

+2 non-oem brake caliper

 

+3 new bumper

 

(your roll bar is probably a free mod, study carefully though)

 

=24 pts if its TTB* base and ends up in TTA, 17pts if its TTB base class and stays in TTB.

 

 

There is a supercharged one at around that power level that does pretty well here in Texas in TTB and there are some pretty quick regulars that run with other types of cars as well. TTA is also a good class to run in but pretty competitive at the pointy end, the championship last year came down to the last session of the last day and was decided by one finishing position difference Can't go wrong running in either class as they both always have enough competitors for tire contingency prizes and the like and the whole group is all really fun to run with

Edited December 21, 2010 by Guest

[kbrew8991]

Since you've added forced induction to a car, you'll need to have it reclassified by dyno/weight.

 

FI miata, TTE right?

 

240whp would decimate that class worse than SpecVinny is (/potstir)

[hustler]

Shit, I left out the springs. My car is very similar to Sixace's supercharged Miata, without the aero and without the Hoosiers. I can't cut the power any lower unfortunately.

 

Thanks for setting me straight.

[kbrew8991]

shoo-shiddily-diddily, I left out the springs. My car is very similar to Sixace's supercharged Miata, without the aero and without the Hoosiers. I can't cut the power any lower unfortunately.

 

Thanks for setting me straight.

 

Yeah I was about to say Dan L. is the guy I'd talk to if I had one of these and was going to run TT, he does pretty well with his

 

Add 2 more pts for the springs to the above and you're on the right track now

[hustler]

shoo-shiddily-diddily, I left out the springs. My car is very similar to Sixace's supercharged Miata, without the aero and without the Hoosiers. I can't cut the power any lower unfortunately.

 

Thanks for setting me straight.

 

Yeah I was about to say Dan L. is the guy I'd talk to if I had one of these Add 2 more pts for the springs to the above then! You're on the right track now

 

I'm, still grasping at straws on the trans and rear end. The 6-speed and LSD were factory items on the 2001+ and 1994+ respectively. The rear end is the same equipment 99% of the Miatas are running and not claiming points for because it came from the factory. I'm also not sure if the tie rod ends are assigned points because the rule reads "ball joints". However I think this rule is made in regard to king-pin angle and "drop spindles" rather than a mild bump-steer correction from an OEM replacement on the tie rod end. If the tie rod end mod warrants +2, then the LSD should receive +10.

 

These are probably age-old complaints and since I'm new to competitive classing my thread is already becoming long in the tooth. I will take the questions up with the regional director.

[kbrew8991]

no worries, that's what this forum is here for (and hey, I'm the outgoing TT director for Texas region so I don't mind, technically its still my job until Jan 1st 2011 Sean Farrah is the incoming guy, I can put you in touch with him if you'd like as well!)

 

the base class parts thing does catch ALOT of Miatas out (alot of other cars too!), but its all about what came on the crappiest no options 1991 Miata in your case. You'll get a free pass on the power stuff when you get your reclassification, but that bumpsteer correction (the tie rod ends from the newer Miata you mention count for this), LSD, transmission all will get you dinged for points. If we did like other clubs (SXXX, etc) you could be scrambling to make sure the VIN on your car is for the right special edition Super Sport Package model and has the right trick stuff from the factory or you'd be just plain illegal for the class depending on what part exactly we're talking about or other such crazyness, and you'd be told exactly how to modify your car for each class you wanted to run. There is a method to this madness

 

If the part you have is not that helpful lap time wise it might be wise to switch back to the OEM definition stuff (stock for a no-option '91), or go really crazy and make sure whatever part is in there is truly worth the full points amount - upgrade beyond what you've got but that still falls under what's described on that particular modification line.

 

The line you'll hear tossed around on this is "Pick your frog, live with the warts". Everyone out there has something they're taking points for that they really feel they shouldn't. Mine is having to take points for 225 width tires even though I only run 225s on the rear, 205s on the front. I feel it should average out to 215s, but it doesn't work that way If there are people not taking points for stuff they should, its always an option as a competitor to ask that their car be inspected closer.

 

Bottom line - come out to an event with the car and get signed off for your TT license. See how you like running with the group! There's always time to change parts to meet the class you want to run later or you can knock it out now - all up to you!

[ff2skip]

Since you've added forced induction to a car, you'll need to have it reclassified by dyno/weight.

 

FI miata, TTE right?

 

240whp would decimate that class worse than SpecVinny is (/potstir)

Thank goodness Vince doesn't have a fastback hardtop. No tellin' how fast he'd go then. :potstirx2:

[wlfpkrcn1]

shoo-shiddily-diddily, I left out the springs. My car is very similar to Sixace's supercharged Miata, without the aero and without the Hoosiers. I can't cut the power any lower unfortunately.

 

Thanks for setting me straight.

 

Yeah I was about to say Dan L. is the guy I'd talk to if I had one of these Add 2 more pts for the springs to the above then! You're on the right track now

 

I'm, still grasping at straws on the trans and rear end. The 6-speed and LSD were factory items on the 2001+ and 1994+ respectively. The rear end is the same equipment 99% of the Miatas are running and not claiming points for because it came from the factory. I'm also not sure if the tie rod ends are assigned points because the rule reads "ball joints". However I think this rule is made in regard to king-pin angle and "drop spindles" rather than a mild bump-steer correction from an OEM replacement on the tie rod end. If the tie rod end mod warrants +2, then the LSD should receive +10.

 

These are probably age-old complaints and since I'm new to competitive classing my thread is already becoming long in the tooth. I will take the questions up with the regional director.

 

Miata did not have a 6 speed until 1999 on the 10th anniversary. So any car with the 6 speed takes +3 points because it was not part of the baseline car 1999 and later. A base Miata does not have a LSD in 90-98, not sure about 99 and later for base equipment. All 90-98 should be taking the +3 "Add LSD" points

[hustler]

Miata did not have a 6 speed until 1999 on the 10th anniversary. So any car with the 6 speed takes +3 points because it was not part of the baseline car 1999 and later. A base Miata does not have a LSD in 90-98, not sure about 99 and later for base equipment. All 90-98 should be taking the +3 "Add LSD" points

I guess I'll suck it up and run spec C5 in my Miata, lol.

[sixace]

Miata did not have a 6 speed until 1999 on the 10th anniversary. So any car with the 6 speed takes +3 points because it was not part of the baseline car 1999 and later. A base Miata does not have a LSD in 90-98, not sure about 99 and later for base equipment. All 90-98 should be taking the +3 "Add LSD" points

I guess I'll suck it up and run spec C5 in my Miata, lol.

 

Hustler

Just turn that little magic knob or whatever you turbo guys do and add another 50 or so hp and you'll be fine. 300hp should be enough to hang with the TTA vettes (and that pesky TTB M3).

 

Ken B.

We'll miss ya. Thanks for last year's fun.

[hustler]

Miata did not have a 6 speed until 1999 on the 10th anniversary. So any car with the 6 speed takes +3 points because it was not part of the baseline car 1999 and later. A base Miata does not have a LSD in 90-98, not sure about 99 and later for base equipment. All 90-98 should be taking the +3 "Add LSD" points

I guess I'll suck it up and run spec C5 in my Miata, lol.

 

Hustler

Just turn that little magic knob or whatever you turbo guys do and add another 50 or so hp and you'll be fine. 300hp should be enough to hang with the TTA vettes (and that pesky TTB M3).

 

Ken B.

We'll miss ya. Thanks for last year's fun.

 

I try not to adjust the "money knob". The more you turn that knob the more money you have to put in it, and the more likely money is to fall out of it.

[kbrew8991]

Dan I'm not going far away or anything, just taking a step back so I can focus on me for once!

[Vinny]

Make sure when you send your reclass in you give power wiggle room. Being a forced inducted car, your car may make 240 in the summer...but actually make 250-260 in the winter on the same exact tune. Don't get caught with your pants down being dyno'd. I dyno my car before every event to make sure its under the legal limit i was given in whatever temp's were racing in that month.

 

Dynojets take into account air temp and humidity, but doesn't mean anything if you car is much more efficient in 60 degree air vs 95 degree air.

[kbrew8991]

SAE correction helps, but yes weather can still swing that number around. Good points Vinny!

[drivinhardz06]

Dynojets take into account air temp and humidity, but doesn't mean anything if you car is much more efficient in 60 degree air vs 95 degree air.

 

yes, the dyno SAE correction can't take into account the internal PCM tables that deal with inlet air temp, and coolant temp (among others) that will have effects on power, regardless of the dyno correction

[hustler]

What is a good rule of thumb for "wiggle room"? I have very little experience on the dyno (tuned about 10-cars on a Mustang) but I have not seen the dramatic fluctuations with air temps. Is 10whp enough smudge factor? Any thoughts on headroom for hp vs headroom for weight.

 

I think it's a combination of gearing advantage and torque, but this car at 232whp is faster than it should be. Is this a point worthy of consideration for classification? Dan, tell me if I'm out in left-field here.

[Varkwso]

Dan I'm not going far away or anything, just taking a step back so I can focus on me for once!

 

 

Funny - we always thought that was the sparkle ponies focus

[awdracer]

For reference, the PTA Miata that won nationals this year put 195hp to the wheels. Unfortunately, I only remember the WHP and not the weight.

[kbrew8991]

I'm vaugley familiar with the car - its got ALOT of points...

 

you can do it with a Miata in A, it just better be built wisely is all

[Varkwso]

I'm vaugley familiar with the car - its got ALOT of points...

 

you can do it with a Miata in A, it just better be built wisely is all

 

With spec C5Z in PTA next year it will be interesting.

[jason]

A miata will probably win it again because all the vettes will be in a pile at the end of the MO backstretch.

[sixace]

What is a good rule of thumb for "wiggle room"? I have very little experience on the dyno (tuned about 10-cars on a Mustang) but I have not seen the dramatic fluctuations with air temps. Is 10whp enough smudge factor? Any thoughts on headroom for hp vs headroom for weight.

 

I think it's a combination of gearing advantage and torque, but this car at 232whp is faster than it should be. Is this a point worthy of consideration for classification? Dan, tell me if I'm out in left-field here.

 

Deeep left field

 

Classification is what it is. Send your dyno file and comp weight (as you pull in from a session). If I was you, I tell Greg to use 250hp for wiggle room and about 10 lbs under actual just in case. Then he'll class you accordingly. Don't like the result? Turn the money knob in the savings direction, re-dyno, and or/add weght.

 

I believe you can send him a few "what ifs" to save dyno time. 250hp/2150lbs, 230/2150, 230/2250 yada yada. He may come back with ranges to stay in a particular class...

 

I sent mine last year a few hp hi, and 25 lbs light (cause I'd hate to lose a race on the scales). I can make my car stay in TTB, but I'll run TTA cause I'm stupid like that and just don't care. Can't beat the M3 so may as well play with the big dogs, hope one or two don't make weight, or run out of gas in each session and I sneak into a 3rd place tire spot. A man's gotta dream right?

 

If you're not running hoho's it's all moot anyways. You could dial it back and become the TTD champ if that twirls yer beanie.