18 replies to this topic

[gkmccready]

1.8L '94-'97 Spec Miata:
+ 7 for suspension (shocks, springs, sway)
+ 3 for LSD
+ 3 for chin spoiler
+ 0 for Toyos (NASA +7 -7) or 3 for SM6 (SCCA +10 -7)
+ 2 exhaust
+ 1 catcon removal
==
16 for Toyo, 19 for SM6 == PTE for both

+ 2 fuel pressure regulator
+ 2 shim the steering rack
==
20 for Toyo, 23 for SM6 == PTD for both

Minimum weight is 2350# for SM which is over the 2330# requirement for PT.

A 1.6 car starting at PTF** has 24 points to stay in PTE, and if you assume they do everything above and take the +1 for an air filter change that car falls in PTE... and if it runs the SM weight of 2300# that's well over the 2182# minimum for the car in PT.

There's nothing that says SMs need to run their restrictors in PT so long as they stay under the PTE pwr:wt (1:16.50). Correct me if I'm wrong about an SM motor, but a "tech shed legal" SM motor seems like a "no points" PT motor?

This makes me think a 1.6 SM that needs to ballast up for SM is the real nice recipe and lets you double-dip SM and PTE! Not the direction I'm actually going, but interesting to think about looking back. I think it's rough on the 1.8 SMs, though, that if they build to the limit of the SM rules they're definitely PTD cars and just barely in that class.

Comments? Have I calculated incorrectly?

[gkmccready]

Am I correct about the motors? And the points classing? Thanks!

[Alberto]

Try Nasaforums.com

[john mueller]

It looks right to me but I'm gonna talk to the PT National Director about the fuel pressure regulator (+2pts) & steering rack shim (+2pts)... Both of these were competitive adjustments to get the NA's 'closer' to NB/NC's and should be 'free'. I cant promise anything but I'd like to see some relief on those somehow.

[gkmccready]

It looks right to me but I'm gonna talk to the PT National Director about the fuel pressure regulator (+2pts) & steering rack shim (+2pts)... Both of these were competitive adjustments to get the NA's 'closer' to NB/NC's and should be 'free'. I cant promise anything but I'd like to see some relief on those somehow.

Over on the NASA Forums the Florida PT director said a "pro" SM motor is typically a +6 (valve job and something else) and that would put both the 1.6 and 1.8 cars deep in to PTE... as I said over there, I'm not looking to rock the boat, just curious after a local 1.6 SM racer said he could swap his Toyos for Hoosiers and stay PTE legal -- it just got me curious because I thought the SMs were just barely falling in to PTE...

And I know you said the shims and FPR were to help the NA, but they look like they're available to everybody in the latest SM rules?

[Alberto]

Regarding the steering rack shim (+2pts), one day at Thunderhill some guy was going on about bump steer and how critical it was to correct the 'problem' on the NA chassis. I thought the guy was going to be fast. Got out for our session session and I wound up blowing by him and never saw him again in my SCCA trimmed 1.6 w/ a stock street engine making a whopping dyno proven 107 HP. I'm on the slow side of the pack.

My point, if you can remove those shims and do something else with your +2 points, do so.

[Jim Drago]

Correct me if I'm wrong about an SM motor, but a "tech shed legal" SM motor

What is a "tech shed legal" engine consist of? I think the rules are pretty well spelled out. h "The rules were spelled out in 2009 to do away with Tech Shed legal" If an engine passes a tear down it is legal, period!

[gkmccready]

What is a "tech shed legal" engine consist of? I think the rules are pretty well spelled out. h "The rules were spelled out in 2009 to do away with Tech Shed legal" If an engine passes a tear down it is legal, period!

Sorry if I touched on a sore spot. I'm not an SM racer and had still heard the motors referred to in that manner. I guess the question really is -- what is done on a "pro" SM motor? How does that map in to the PT rules?

[Mike Colangelo]

It looks right to me but I'm gonna talk to the PT National Director about the fuel pressure regulator (+2pts) & steering rack shim (+2pts)... Both of these were competitive adjustments to get the NA's 'closer' to NB/NC's and should be 'free'. I cant promise anything but I'd like to see some relief on those somehow.

Hi John,

Any word on the FPR being free for SMs in PT?

I'm surprised that there isn't a PT classification for SM-legal cars (e.g., all SM-legal Miatas will be classed in PTD or something like that).

[john mueller]

Hi John,

Any word on the FPR being free for SMs in PT?

I'm surprised that there isn't a PT classification for SM-legal cars (e.g., all SM-legal Miatas will be classed in PTD or something like that).

Mike;
I got a very cold reception to my recommendations last season but I'm going to make another attempt along your way of thinking this year.

[Caveman-kwebb99]

I know from experience a SM with a RP pulled is not ever going to be even remotely competitve in PTD. It really wont even compete as a PTE car especially if you follow the thinking that an SM head is 6pts.

Bottom line is NASA wants you to race your miata in SM... If you want to be a serious PT competitor buy a honda and tweek it to the max. Honda's have easily won the last 2 Nasa champs, despite me maxing my PT miata to the very edge of the rules. I ran in p1 for half of the last national championship, but eventually the Honda's and even the RX7 overcame me with their superior straight line speeds.

All SM cars should be classified as PTE regardless of chin spoilers, RP regulators, or whatever tire you run period AMEN.

[FTodaro]

The other problem is that if your looking to double dip for time on the track they run the PT cars with the SM cars so you are either going to run one or the other but not both.

[john mueller]

The other problem is that if your looking to double dip for time on the track they run the PT cars with the SM cars so you are either going to run one or the other but not both.

Frank, this is not the case in every region.

[Rob Burgoon]

I know from experience a SM with a RP pulled is not ever going to be even remotely competitve in PTD. It really wont even compete as a PTE car especially if you follow the thinking that an SM head is 6pts.

No kidding. Last race in socal the PTE winning miata beat the fastest SM's best lap by 3.5 seconds.

[FTodaro]

Frank, this is not the case in every region.

John Did not know that, it is true for the Great Lakes region.

[Mike Colangelo]

Thanks for the info.

Maybe I'll just double dip in HPDE4/Time Trials.

[aCab]

You could also get your car dyno reclassed and not take any points for anything under section D. for the engine.

You specify two of the following and the National Director specifices the 3rd:

Class
HP
Weight

That's the route Id go to get a SM more competitive. However, something like the chin spoiler is a waste of points. Id lose it for running PTE/TTE, or just suck it up.

[RazerX]

1.8L '94-'97 Spec Miata:
+ 7 for suspension (shocks, springs, sway)
+ 3 for LSD
+ 3 for chin spoiler
+ 0 for Toyos (NASA +7 -7) or 3 for SM6 (SCCA +10 -7)
+ 2 exhaust
+ 1 catcon removal
==
16 for Toyo, 19 for SM6 == PTE for both

+ 2 fuel pressure regulator
+ 2 shim the steering rack
==
20 for Toyo, 23 for SM6 == PTD for both

Minimum weight is 2350# for SM which is over the 2330# requirement for PT.

A 1.6 car starting at PTF** has 24 points to stay in PTE, and if you assume they do everything above and take the +1 for an air filter change that car falls in PTE... and if it runs the SM weight of 2300# that's well over the 2182# minimum for the car in PT.

There's nothing that says SMs need to run their restrictors in PT so long as they stay under the PTE pwr:wt (1:16.50). Correct me if I'm wrong about an SM motor, but a "tech shed legal" SM motor seems like a "no points" PT motor?

This makes me think a 1.6 SM that needs to ballast up for SM is the real nice recipe and lets you double-dip SM and PTE! Not the direction I'm actually going, but interesting to think about looking back. I think it's rough on the 1.8 SMs, though, that if they build to the limit of the SM rules they're definitely PTD cars and just barely in that class.

Comments? Have I calculated incorrectly?

I have a 1.6 and not a slug, run both SM and PTE. I can say that running against a 1.8 is a challenge when they remove that restricter plate. It is something close to 10 HP and and some very nice torque. I think this year they can run RRs w/o points so.. not such an advantage. I also ran in the enduros against other E3 and the 1.6 is outclassed by everything.

[gkmccready]

I have a 1.6 and not a slug, run both SM and PTE. I can say that running against a 1.8 is a challenge when they remove that restricter plate. It is something close to 10 HP and and some very nice torque. I think this year they can run RRs w/o points so.. not such an advantage. I also ran in the enduros against other E3 and the 1.6 is outclassed by everything.

You quoted a year old post. :-) These days if you take a fully built to the rules 1.6 or 1.8 SM (either SCCA or NASA) it lands in PTD. If you're not quite built to the rules you can squeeze in PTE. They got rid of the "All SMs map to PTE" classing a couple of years ago in the PT rules...