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SCCAITS 06-09-11 05:38 PM

Here are 2 actual dyno reclasses on a 2nd Gen that I got somewhere....

183rwhp/2535lb - PTD*

192rwhp/2350 - PTC*

Maybe one day someone will figure out the secret formula...

These dyno reclassing shows that 9rwhp and 185lbs caused a full class jump (39 points). The rules have weight reduction of 185lbs worth +13. Can't believe 9rwhp is worth 26 points.

wlfpkrcn 06-09-11 06:25 PM


Originally Posted by SCCAITS (Post 10659607)
Here are 2 actual dyno reclasses on a 2nd Gen that I got somewhere....

183rwhp/2535lb - PTD*

192rwhp/2350 - PTC*

Maybe one day someone will figure out the secret formula...

These dyno reclassing shows that 9rwhp and 185lbs caused a full class jump (39 points). The rules have weight reduction of 185lbs worth +13. Can't believe 9rwhp is worth 26 points.

It would good to note that Tinner is technically a reclassed TII. So he should be taking points for brakes, aero and lsd in his base class of PTD @ 2850

088 06-09-11 06:48 PM

Wheels are a no-points mod, correct? So you could run the stock 15x6 or 17x8 or whatever and just take points for treadwear, tire width (and adjust PtW ratio accordingly).

wlfpkrcn 06-09-11 07:06 PM

Wheels are open. If you think running a big wheel with wide tire is the answer then that option is open.

If your plan is PTD you shouldn't be thinking anymore than 165ish @ 2800. If your plan is to dyno class.

A- Figure out the HP you want and and a base classing you want. Then Email Greg and he will let you know what to weigh.

B- If you have a HP and weight in mind you can request it, he will class it. It may not be what you are expecting.

In other words don't figure out the max Hp/Wt for PTD and request it

tinner 06-09-11 07:33 PM


Originally Posted by wlfpkrcn (Post 10659680)
It would good to note that Tinner is technically a reclassed TII. So he should be taking points for brakes, aero and lsd in his base class of PTD @ 2850

Actually, because my car is classed as a TII I do not need to take points for brakes, lsd, and aero. I thought it would be the best way to go considering my horsepower would land me in D anyways. What I ended up with is a car with the exact hp to weight ratio of one of my competitors supercharged Miata.

wlfpkrcn 06-09-11 07:38 PM


Originally Posted by tinner (Post 10659775)
Actually, because my car is classed as a TII I do not need to take points for brakes, lsd, and aero. I thought it would be the best way to go considering my horsepower would land me in D anyways. What I ended up with is a car with the exact hp to weight ratio of one of my competitors supercharged Miata.

Thats what I meant but it didn't come out right...Those items are already part of your base classing

Are you using a TII trans with adapter plate or the Chevy trans?

What is your points breakdown currently?

tinner 06-09-11 08:08 PM


Originally Posted by wlfpkrcn (Post 10659780)
Thats what I meant but it didn't come out right...Those items are already part of your base classing

Are you using a TII trans with adapter plate or the Chevy trans?

What is your points breakdown currently?

Greg allowed me to use the GM transmission as part of the swap without taking additional points. I am looking at adapting a TII transmission as the GM T5's ratios are absolute crap.

I'm still working on my PT formula, as of now though,

PTD base no stars.
+3 aftermarket shocks
+1 inverted shocks
+2 springs
+2 sway bars
+3 air dam
+8 Toyo RA1s
19 total

Or

+3 aftermarket shocks
+1 inverted shocks
+2 springs
+2 sway bars
+3 air dam
+6 BFG R1s
+2 -34lbs
19 total

I'm looking to ditch the air dam if I can find a factory S5 TII front lip to take it's place, it would only be an inch-ish shorter than my current air dam and free up 3 precious points.

wlfpkrcn 06-09-11 08:41 PM

May want to rethink option B


If a vehicle that has been reclassified based on its actual competition weight and Dyno power
output is found to weigh less than the Minimum Competition Weight listed on its Car
Classification Form, it will be assessed two (2) penalty points for any deviation below the listed
weight, followed by one (1) additional penalty point for each five (5) pounds below the listed
Minimum Competition Weight.
Following the NASA CCR 17.8, there will be a five (5.0) pound
leeway allowed during the first time the vehicle is weighed for that event (weekend). There will
be no leeway at subsequent weighings for the remainder of the event. Appropriate penalties will
then be assessed per the PT rules (6.4), including a penalty for a Procedural Violation for any
vehicle failing to meet the Minimum Competition Weight listed on the Car Classification Form.
The way I read/understand that is- Once you are Dyno classed that is your weight unless you request classing at a lower weight. However I could be completely wrong. It has happened before

wlfpkrcn 06-09-11 08:49 PM


Originally Posted by wlfpkrcn (Post 10659742)
Wheels are open. If you think running a big wheel with wide tire is the answer then that option is open.

If your plan is PTD you shouldn't be thinking anymore than 165ish @ 2800. If your plan is to dyno class.

A- Figure out the HP you want and and a base classing you want. Then Email Greg and he will let you know what to weigh.

B- If you have a HP and weight in mind you can request it, he will class it. It may not be what you are expecting.

In other words don't figure out the max Hp/Wt for PTD and request it


What I mean there is you want your base class as PTE to build up to PTD with 39 points to use, you should be looking at 165ish @2800

PTE with * or ** is possible as well if you don't want the full 39 points

PTD with 19 points if you know where to spend it. Sounds like Tinner is walking the tight rope with that option

wlfpkrcn 06-09-11 08:57 PM


Originally Posted by RockLobster (Post 10659593)
Yeah i saw it but i do recall a previous year rulset stating "greater than one range of adjustment"

I assume that was when the price of the shocks determined the points the shock took

SCCAITS 06-10-11 06:39 AM


Originally Posted by tinner (Post 10659824)
Greg allowed me to use the GM transmission as part of the swap without taking additional points.

Nothing personal and not aimed at you, but this type of thing is what is wrong with PT. The entire series is built around the thoughts, opinions, interpretations and feelings of one guy. When you start having one guy class cars rather than rule book, it gets screwy. More proof the dyno reclass is not pure formula, it's part formula, part opinion.




Originally Posted by wlfpkrcn (Post 10659865)
The way I read/understand that is- Once you are Dyno classed that is your weight unless you request classing at a lower weight.

"We do not allow competitors using Dyno/wt based classing to then use excess points to drop further weight. The minimum weight is fixed based on the re-classing." I got that in writing from Greg when I asked awhile back.

RockLobster 06-10-11 08:26 AM


Originally Posted by wlfpkrcn (Post 10659896)
I assume that was when the price of the shocks determined the points the shock took

Must have been...i am glad they got rid of that screwy rule...

tinner 06-10-11 09:42 AM


Originally Posted by wlfpkrcn (Post 10659865)
May want to rethink option B



The way I read/understand that is- Once you are Dyno classed that is your weight unless you request classing at a lower weight. However I could be completely wrong. It has happened before

Thanks for the heads up on that. Looks like I need to find somewhere to spend those two points, I hate to leave anything on the table.


Originally Posted by SCCAITS (Post 10660283)
Nothing personal and not aimed at you, but this type of thing is what is wrong with PT. The entire series is built around the thoughts, opinions, interpretations and feelings of one guy. When you start having one guy class cars rather than rule book, it gets screwy. More proof the dyno reclass is not pure formula, it's part formula, part opinion.

I couldn't disagree more but I'm not going to argue that with you. But trying to use my transmission swap to make your case is kinda out of left field. Allowing the T5 in my car offers zero performance advantage, in fact it is quite the disadvantage, what it does allow is one more car to compete and one more driver to have a good time.

wlfpkrcn 06-10-11 02:47 PM


Originally Posted by tinner (Post 10660440)



Originally Posted by SCCAITS View Post
Nothing personal and not aimed at you, but this type of thing is what is wrong with PT. The entire series is built around the thoughts, opinions, interpretations and feelings of one guy. When you start having one guy class cars rather than rule book, it gets screwy. More proof the dyno reclass is not pure formula, it's part formula, part opinion.

I couldn't disagree more but I'm not going to argue that with you. But trying to use my transmission swap to make your case is kinda out of left field. Allowing the T5 in my car offers zero performance advantage, in fact it is quite the disadvantage, what it does allow is one more car to compete and one more driver to have a good time.


Both of you have valid points.

If you are trying to build a nationally competitive car. It is an unknown moving target. You just hope you get a favorable Dyno Reclass and go for it.
Unfortunately the FC has some unaccountable magic that gets hit harder than other cars.

If you are out having fun on a budget and able to compete. That is what this class is perfect for.

My opinion from the get go is- This class is designed and structured for street car to TT. It works for the masses not trying to max out a car to the rules

088 06-10-11 03:40 PM


Originally Posted by wlfpkrcn (Post 10659882)
What I mean there is you want your base class as PTE to build up to PTD with 39 points to use, you should be looking at 165ish @2800

PTE with * or ** is possible as well if you don't want the full 39 points


Originally Posted by wlfpkrcn (Post 10659865)
Once you are Dyno classed that is your weight unless you request classing at a lower weight. However I could be completely wrong. It has happened before


Originally Posted by SCCAITS (Post 10660283)
"We do not allow competitors using Dyno/wt based classing to then use excess points to drop further weight. The minimum weight is fixed based on the re-classing." I got that in writing from Greg when I asked awhile back.

wlfpkrcn -- thanks for the advice. So -- ideally, I should start with the lowest class possible with either 19 (stay in class) or 39 points (bump up) to play. According to Mike Haag, a properly built and tuned engine will make in excess of 180 whp, which is great for ITS but not PT. This is what got me concerned about the adjusted PtW ratio in the first place. What I don't want is to start with PTD and end up in PTC.

Then there's the cost consideration. Rebuild vs. purchase used engine vs. run what I have. It's pretty hard to find a used engine that makes decent power (so you can just throw it into a car without a refresh). But I think I may have stumbled upon one -- at a very good price. Unfortunately, it's streetported, so I'm again concerned that it may turn out to be too powerful.

As it stands, the car currently has an underpowered streetported engine with essentially maxed out tuning, making 139 hp. And the car already has enough modifications to exceed 19 points, requiring up-classing. At 2800 lbs, the car would be a dog in PTD.

In any case, what I'm gathering from some of the weight discussion is this. Let's say my car weighs 2840 lbs. Should I report the weight as 2801, thereby getting some "free" weight reduction capability (provided dropping 39 lbs. does not change the adjusted PtW ratio sufficiently to affect classification)?

RockLobster 06-10-11 05:21 PM

The rub is that the only place you will see a lot of stiff competition is at nationals. The reality is PT classes are pretty sparse in the regional races...

At nationals you end up against pro teams like RDR. So its the other problem of facing guys with pretty big budgets and direct factory support...

I run a PT car because i love nasa as an organization, i know the FC better than any other car and love driving it on the track...and RX-7s have no home other than PT/ST in nasa...

We all just hope Greg is indeed using a super secret formula and sticking to it in all cases...

088 06-10-11 06:05 PM

Ok. Got some input offline as well. Interesting discussions. If it weren't for a multitude of other problems with the car, I'd be showing up to Sears Point this weekend. Norcal guys -- have fun out there!

RockLobster 07-18-11 03:52 PM

Signed up for nationals....who else is going!

tinner 08-31-11 06:22 PM


Originally Posted by RockLobster (Post 10710146)
Signed up for nationals....who else is going!


I'm in.

I'll be paddocked in the grass near the restrooms with a hoard of Hondas. Stop by if you get a a chance. If not, I'll see you on track.

Good luck!

D Walker 09-02-11 09:11 AM

I will be there with a BMW M3 running in GTS4, could bring the RX8 out but do not have a driver/renter for it.

088 02-14-12 02:26 PM


Originally Posted by wlfpkrcn (Post 10659553)
Brakes- You will want at least the 4 pistons if not some AM wilwoods etc- 2

Ok, so even the stock 4-piston calipers are +2 points (because the base GTU model came with the single-pistons for all years 1986-1991)?

wlfpkrcn 02-14-12 06:14 PM


Originally Posted by 088 (Post 10979282)
Ok, so even the stock 4-piston calipers are +2 points (because the base GTU model came with the single-pistons for all years 1986-1991)?

Yes the 4 pistons are +2pt. Were you at Infineon running in PTD?
http://www.gotbluemilk.com/web120212...s/image33.html

If so what points did you take?

088 02-23-12 07:58 PM

Yes, I was there. Here is what I came up with.

Dyno Re-class to PTE**

+14 PTE**
+11 tires: tw=40; width=245
+0 weight (dyno re-class)
+0 engine (dyno re-class)
+3 drivetrain: LSD
+8 suspension: coilovers, fronts inverted; swaybars
+2 brakes: four-piston calipers
+0 aero
+0 roll cage attachment

+38 total, move up to PTD final competition class

Basically, it's a re-class with the mods you listed in post 69 plus brakes.

088 02-23-12 08:00 PM

^ and it wasn't nearly enough to catch The General in his PTD Miata

wlfpkrcn 02-23-12 11:13 PM

What was your dyno reclassified wt/HP? The general? What is your diff ratio? Are you going to be at the march event?


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