2009 NASA TT

[Sylvan]

So, checking out the new rules, all factory turbo cars get assessed +5 modifications points. Ouch.

So a base MR2 turbo is classed TTE** +5, so that's 1 point away from TTD, correct? That kinda sucks.

However, now an ECU reflash is considered a free mod, so I could take a bone stock MR2T, reflash the ECU, and stay in TTE, but what can we get from a reflash? Raised rev limiter, timing map changes maybe.. is that really much of a benefit? Seems like turbo guys are getting boned this year.

Could I dyno my car bone-stock, and be classed TTE** based on dyno/weight without having to take the +5 turbo points?

Scenario 2------
Say I was planning to compete in TTD anyway, and I wanted to get dyno/weight classed into the low end of TTD so I could do some suspension and tire mods and stay within the class. Could I run any power mods like intercooler, downpipe, exhaust, etc, but low boost pressure (wastegate spring) as long as my peak power and weight kept me in TTD? Does the online classifier let you run all these hypothetical scenarios? I realize it's down at the moment while they update it with the new rules.

Another thing, I would like to make sure I'm interpreting the OEM-part rules correctly. My car is a 91, but could I swap in any OEM part from say a 94 or 95 USDM car, such as front lip, sway bars, spoiler, etc. as long as it wasn't optional equipment (like the LSD transaxle)?

Thanks. I realize the NASA forums would probably be a better place to ask, but I haven't registered there yet and I don't want to get flamed over there

[Gairloch]

I'm afraid it's been a while since I checked out the TT rules. I wouldn't worry too much about getting flamed on the NASA forums, they're pretty civil over there. The regional directors tend to pay pretty close attention so things don't get too far out of hand.

[kbrew8991]

if I were building a Mk2 Turbo for TT/PT I'd definitely want to get it reclassed by dyno & weight. If you know the weight you can ask really nice and get a few options for whp (ie at 2900lbs Xwhp for TTE**, Ywhp for TTD, Zwhp for TTD*...)

You can make your car a 93+, but you are right in keeping an eye out for option type stuff like the LSD for our cars specifically. Spoiler is free, thank goodness the spoiler delete was the option instead of spoiler addition, eh?

hope that helps!

- Ken, fielding a '94 NA for TTF & PTF, Nationals bound, gunning for 2 championships....

[Sylvan]

Originally Posted by kbrew8991

if I were building a Mk2 Turbo for TT/PT I'd definitely want to get it reclassed by dyno & weight. If you know the weight you can ask really nice and get a few options for whp (ie at 2900lbs Xwhp for TTE**, Ywhp for TTD, Zwhp for TTD*...)

You can make your car a 93+, but you are right in keeping an eye out for option type stuff like the LSD for our cars specifically. Spoiler is free, thank goodness the spoiler delete was the option instead of spoiler addition, eh?

hope that helps!

- Ken, fielding a '94 NA for TTF & PTF, Nationals bound, gunning for 2 championships....

Cool, thanks for the info. I'm thinking I might try starting out next year, so I have the remainder of this year to get my plan figured out, car prepped, and get my license. I'm such a newb to any kind of competition so I'll get schooled for awhile (in ever sense of that word), but it should be fun. I'll let you know when I start prepping the car and maybe we could share some tips

[Sylvan]

So here's one potential setup I've come up with to put an MR2 Turbo into TTD:

Base class: TTE**
**: +14 points
Turbo: +5 points
2) DOT-approved R-compound tires with a UTQG treadwear rating of 50 to 130 (ex. Kumho V700, Michelin Pilot Sport
Cup, Nitto NT01, Pirelli PZero Corsa, Toyo R888, Yokahama A048, etc.— note: see exception below in 3)) +7
3) Non-OEM or modified/re-valved shocks/struts/dampers +3 (all others)(springs not included)
4) Non-OEM or modified coil springs, leaf springs/spacers/brackets, or torsion bars +2
16) Aftermarket or modified wastegate actuator, wastegate, or vacuum line(s) that
serve to control the wastegate actuator function or increase peak boost +3
18) Non-OEM or modified intercooler +4
27) Non-OEM or modified exhaust piping, resonators, or mufflers downstream from the OEM catalytic converter(s)
locations(s) +1 (for basic “catback” exhaust or performance mufflers only—otherwise, must use 26)

Total: +39 points, maxed out for TTD.
Target weight 2825 lbs for no weight reduction penalty.
Target power, whatever I can get from increased boost and an intercooler. With 2825 lb, I believe I'm limited to < 204 rwhp. I doubt I would hit that given the mods I have listed above, but I'll check it out on the dyno and see what I come up with.
Tires: 225f/245r
Free mods: whatever I can do that applies to my car

My thoughts were to mod the wastegate with maybe a helper spring, or mod the inside with a stiffer spring to force an increased boost pressure.
Suspension would probably be Konis with some springs, not sure which ones yet.
Everything else would be stock.


What do you guys think?

[kbrew8991]

that came to 40 points by my tally...? You'll get dinged +1 for 245s (vs 235 from your base class - your "tire width" is always tied to your base class). Easy one to forget 203.9whp max if you're going to weigh 2825lbs on the nose and run 245s or smaller to stay within the adjusted hp/weight cap

I'd HIGHLY recommend getting some reclass stuff done, get the weight figured out and ask for what max power level you can have for a base class that suits the rest of your build (remember, once reclassed by hp:weight, you no longer take weight reduction or power modification points - plus your "base tire width" may change, giving you extra to play with). Easiest way to show you this is as follows

Lets say you actually weigh in at 2900lbs and dyno at 195whp or something (this HAS to come from the national guy though) and it gets reclassed to TTD (instead of TTE**). With no other changes to your modification setup you go from +1 over maxed out for TTD to 4 points to spend before maxing out in TTD. Thats the difference between 2nd tier R-comps & Top Tier R-comps... (and still 1 point to spend actually...)

[Sylvan]

Aw man, I thought the tire size was based on your competing class, not your base class Oh well... in that case you're right it pushes me to +40 points

The reason I thought of just taking the engine mod points rather than getting a new base class based on dyno/weight, was because I read from one of the guys on the NASA forums that if you dyno/weigh close to or at the minimum adjusted weight/hp, you will most likely get a TTD** which would leave me 5 points for suspension and no tire.

It's definitely worth looking into though, since at this point I have no idea what the cutoff numbers are for dyno classing into TTD, TTD*, or TTD**. But if I can hit close to the minimum weight/hp with just a wastegate mod, IC, and exhuast (+8 engine points), then I might be better off. But, I'm just theorizing at this point.

Thanks for the feedback. I'll take a look at some 235 tire setups. Do you think 225f/235r would be hard to handle from an oversteering standpoint?

[kbrew8991]

it should be alright - I did 195s/205s for '07 Nats... nothing alignment tweaks couldn't solve anyway

you aren't forced into the reclass even after you ask for it - its just another option to look at is all

[kbrew8991]

I think I have solidified my setup for this year

car is listed as PTF* / TTF* - 2657lbs, so:
+7 from asterix
+10 for Hoosier Rs (or maybe even As if I'm really brave/spendy/etc)
+1 for 225s
+1 for the "catback" I've got a good friend fabricating for me
= 19 total, maxed out in F

I will probably need about 50-65lbs bolted to the passenger floor at that weight, but its not a bad location for the weight - better than carrying it at the wheels and hanging off the back of the car imo

That Hoosier contingency deal sealed it for me - I've got a decent shot at earning 3-4 tires per weekend with my region (large PTF field, and possibly from TTF as well)

Next year I will likely modify up to TTE / PTE

[Sylvan]

Looking good. So do you find that you're at a disadvantage against other cars in your class in terms of power?

How do you like the Hoosiers? I really want to try them. What's the difference between the Hoosier A6's and R6's? I couldn't find any difference in description on the Tirerack other than different choices in size.

[kbrew8991]

with my '91 I made up enough in the corners and braking at Mid-Ohio to do pretty damn well (3rd in '06, 2nd in '07 Nationally) despite a deficit of 119whp ( & 2700lbs) vs 135whp ( & 2800lbs) for '07 especially. At Miller this coming year... we'll see. Only one way to find out...

R6 = 6th gen Road Race compound
A6 = 6th gen Autocross compound

I know people that race (20, 40, 60 min sprints) on A6s, but we're talking light cars that are easy on tires (CRX, Miata etc). I think it would be a good Time Trials tire for our cars if you can get it done in 2-3 laps, but I would not expect to be fast at the end of a race with them...

I have yet to play with the A6 or R6, only the A5s. Grippy tire, but not the most forgiving if you ask just a weee bit too much of it. No audible communication from them until after the first full spin it seemed, haha. I am told the A6 is better, and the R6 is very nice in terms of forgiveness as compared to the older stuff.... but I have no seat time on them yet.

I do know I absolutely LOVED the Kumho V710 as a time trials tire (except longevity, geez they corded fast), but you'd better get it done in the first or second hotlap.... very grippy, very progressive, very communicative through noise as well as feel, etc.

We'll see how the R6 stacks up, 'cause Kumho doesn't pay you in tires like Hoosier does.. and there isn't much else in the "top tier" that I would look at that could possibly last a full 40-60 minute sprint. Maybe the BFG... but again they don't pay tires

[Sylvan]

Cool, I'd be interested to hear your opinions of the R6 when you get a chance to try them out. By the way, do you have any pics of your cage setup? Not that I'm ready to go there yet, but it would be nice to know for future planning purposes. Do you have a rear bar welded to the firewall behind the main hoop, or does it penetrate and go to the shock towers? Do you have to use a petty bar? Thanks!

[kbrew8991]

this car came with a petty bar setup, and no rear main hoop braces - its about 2-3" in front of the rear firewall, so between the two it'll work. But I am looking at going through the rear window when I rework it later on - there are many other things I want to change on it (main hoop height, path of a-pillar and halo sections, etc), easier to scrap it and start over when its time for that.

Its logbooked for SCCA and NASA as it sits, good enough to cut my race teeth on