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Old 02-02-2015, 12:25 PM
  #141  
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Is that enough power in D? aren't E cars getting close to 160? Why don't you just put as much weight as you can in the car, I think "ballast" is limited to 250lbs... but put back everything you took out for weight savings. Then send him your weight and see what power number he gives you. I would think a D car needs >185hp.
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Old 02-02-2015, 01:32 PM
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Originally Posted by Codersozer
Is that enough power in D? aren't E cars getting close to 160? Why don't you just put as much weight as you can in the car, I think "ballast" is limited to 250lbs... but put back everything you took out for weight savings. Then send him your weight and see what power number he gives you. I would think a D car needs >185hp.
seriously? you would need a porky miata to get away with 160hp in PT/TTE. its not a power figure, its a power to weight.

PTE weight/power 16.5:1

16.5 = x/160

x= 2640.

Since our race weight is established by the chart, you can't really run at 2640 without a dyno reclass, in which case you are not likely to get 16.5.
You are really looking more at about 145 whp for a points based PTE car.
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Old 02-02-2015, 01:59 PM
  #143  
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Yeah, 160 and 185 are closer to D and C reclass numbers, not E and D.

I think Andrew's point was that you should be making the car as heavy as possible and then requesting a reclass at that weight with whatever letter and number of stars you want. Let Greg tell you your max power number and then build the engine to hit that number. I fully agree with this approach for PT.
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Old 02-02-2015, 05:26 PM
  #144  
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Originally Posted by Seefo
Since our race weight is established by the chart, you can't really run at 2640 without a dyno reclass,
I thought the Minimum weight was on the chart and we could declare a higher Minimum Competition Weight on the classing form if we wanted to.

My plan was to put in a MS-PNP and try to get 150 HP at 2,485 lbs for TTE points based classing.
16.5 base + .8 tires - .75 weight = 16.55 * 150 hp = 2,482 lbs.
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Old 02-02-2015, 06:21 PM
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Originally Posted by Seefo
seriously? you would need a porky miata to get away with 160hp in PT/TTE. its not a power figure, its a power to weight.

PTE weight/power 16.5:1

16.5 = x/160

x= 2640.

Since our race weight is established by the chart, you can't really run at 2640 without a dyno reclass, in which case you are not likely to get 16.5.
You are really looking more at about 145 whp for a points based PTE car.

It's entirely possible. I had my car with 250lbs of ballast, and nothing else, at 2520. I don't think 2600+ is very far off either. Bulky interior pieces, bigger diameter cage tubing, heavy wheels, a cool suit, etc... It's for sure possible.
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Old 02-02-2015, 06:40 PM
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Originally Posted by EricJ
I thought the Minimum weight was on the chart and we could declare a higher Minimum Competition Weight on the classing form if we wanted to.

My plan was to put in a MS-PNP and try to get 150 HP at 2,485 lbs for TTE points based classing.
16.5 base + .8 tires - .75 weight = 16.55 * 150 hp = 2,482 lbs.
I get that you can declare a higher weight, but good luck making 160 whp with the points left over after tires + suspension. It doesn't seem reasonable unless you dyno reclass, which is what I am trying to say.

you can dyno reclass and give them a weight of 2600 or whatever, but he is not going to give you 160 whp in that case. Not for PTE anyway.


Definitely get Andrew's point and I agree. As unmiata-ish as it sounds, it definitely works for the NASA formula. Unless you have a NB1 apparently.
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Old 02-03-2015, 07:25 PM
  #147  
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Last year I was at 18 points, suspension, I/H/E, w/ 205 RRs. I got 2 points back this year with the RRs, so 3 points are available for a MS-PNP. I won't make 160, but near 150 is possible.
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Old 02-05-2015, 10:12 AM
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Originally Posted by EricJ
Last year I was at 18 points, suspension, I/H/E, w/ 205 RRs. I got 2 points back this year with the RRs, so 3 points are available for a MS-PNP. I won't make 160, but near 150 is possible.
what did you make with the I/H/E on the 99 motor?
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Old 02-05-2015, 06:28 PM
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Originally Posted by Seefo
what did you make with the I/H/E on the 99 motor?
No idea, I've never dyno'd it. Seeing results of others similarly equipped cars I'm guessing near 125, no where near my 145 hp limit @ 2400 lbs.
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Old 03-05-2015, 12:44 PM
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2310 min comp weight, 154 max whp, which I'm just about at. TTD Base class. I'm having a lot of trouble deciding on tires, especially with little info/testing on the new R7s. With no aero, I'm at 18 points with 225 R7s. Any A7 is out of the question on points now. I think I'd be faster with 205 R7s and a SuperMiata style front air dam, but I'm not sure I will have time to put that together, and 225s will probably give me better tire life. I'm not looking to win nationals, but there's an M3 in my region that I've been routinely 1-3 seconds behind and I'm sick of 2nd place, especially when we have fields big enough for 1st place tires. I've never been on good tires though during competition.

Last edited by dasting; 03-05-2015 at 12:47 PM. Reason: missing words
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Old 03-05-2015, 02:32 PM
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If you can't make more power, go back to 205 R7s, use the 6 points plus the 1 extra you already have to reclass TTD*, and pull a bunch of weight from the car. You will go faster.

The better option would be to reclass TTD* and add 150-200lbs to the car along with a big pile of horsepower.
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Old 03-05-2015, 03:47 PM
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Interesting, thanks. I can get to about 2200 pounds comp weight fairly easily. More hp isn't an option this season.
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Old 03-05-2015, 04:32 PM
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In general, an E* or D* reclass will always be the best option. The primary goal in PT should be to get as close as possible to your class power/weight cap while spending the fewest number of points to do it. Non-star reclasses always give up a lot of room to the class cap. Star reclasses still give up some room, but it gets you a lot closer than you otherwise would be.

IOW, you will never spend those 7 points better than using them to add a bunch of power (or remove a bunch of weight).
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Old 03-05-2015, 04:35 PM
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Makes a lot of sense. Thanks again, I emailed Greg for a TTD* re-class. I guess 205 R7s will shipping to me once this cold spell breaks. 5 weeks until first competition.
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Old 03-05-2015, 09:27 PM
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Originally Posted by GraemeD
Here is the 2014 email from Greg:
Your '94 Mazda Miata with a 1.8L VVT Miata head and a maximum 161 rwhp on a Dynojet, and a Minimum Competition Weight (w/driver) of 2360 lbs, will have a new PT/TT base class of PTD*/TTD* (seven points). Your new base tire size is 245mm. You will not assess modification points for Section B. Weight Reduction or Section C. Engine Mods. You may update to '01-'05 Mazda Miata brakes without a points assessment as well. However, all other modifications, including transmission and LSD, that are not standard items on a base trim '94 Mazda Miata must be assessed points. You must be compliant with the above listed maximum Dynojet HP and Minimum Competition Weight during any tech. inspection.


So that's what I went with. I had to add about 50 lbs.

We will see what 2015 brings. I am going to dyno it agin, because I don't think it is making that much power. Hopefully I can get those 7 points back. And use them for aero.
What would be the estimated rwhp for a '92 TTE* dyno reclass at the same weight of 2360?
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Old 03-05-2015, 10:24 PM
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Old 03-11-2015, 03:58 PM
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Just got my new re-class for TTD*

2255 pounds @ 154 whp. That's vs my TTD reclass, 2310 pounds @154whp. 205 R7s it is, losing that extra weight is nice because now I can run my tank down lower. TBH, I was hoping for a lower TTD* comp weight, but oh well.
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Old 03-12-2015, 03:56 AM
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That's a good * reclass ratio for D.
Tell me about your car? Where are you running as well?
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Old 03-12-2015, 01:27 PM
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I run with NASA NE- Mostly The Glen, NJMP and Lime Rock. Car is fun, originally a pretty well prepped CSP car- 96 chassis, junk yard VVT swap w/80k miles or so, makes just over 150whp based on two different dynojets. No aero. Decade old suspension tech that surprisingly still works well (JIC FLT Magics). Haven't really autocrossed in a couple years since getting the track bug, and last year was my first full TT season. My points aren't quite optimized. A friend was selling a brand new 949 11.75" BBK that I jumped on for a good price because I was chewing through pads, so that's wasted points vs using OEM sport brakes. I'd love to go to 4.77 gears, but I just don't have the time.
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Old 03-17-2015, 10:33 AM
  #160  
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Originally Posted by EricJ
I thought the Minimum weight was on the chart and we could declare a higher Minimum Competition Weight on the classing form if we wanted to.

My plan was to put in a MS-PNP and try to get 150 HP at 2,485 lbs for TTE points based classing.
16.5 base + .8 tires - .75 weight = 16.55 * 150 hp = 2,482 lbs.

It's a grey area. I did this at nationals and it took some convincing for greg to allow it. It's of course only applicable to points classed cars.

It states in the rules that you CAN do this but according to Greg it's at the discretion of the class director.
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