I'm bringing this thread down from the Second Gen specific section
https://www.rx7club.com/showthread.p...1#post10415265

Post a pic of your car and points you are taking. Maybe we can figure out the ultimate PT FC. So far there are 3 cars, each with a different approach.

Here is mine



Here is how we point out and stay in PTD (basically it's keeping the weight)
Current points with car at 2800lb coming off the track with driver

9- Tires- 10 point 225's We lose a point for width
1- cold air intake
1- under drive pulley
2- header
2- exhaust
1- cat conv removal
3- limited slip
3- shocks
2- springs
2- sway bar
3- bushings (spherical and solid metallic)
2- brake calipers
3- splitter
3- facia/air dam

Total is 37. I will use the extra 2 points for weight reduction to be safe

 

Tinner



My base class is PTD as a TII with an engine swap, dyno classed at 185rwhp at 2850lbs.
+8 tires, 255 RA1, base tire in PTD is 245
+3 shocks
+1 inverted shocks, the Stance coilover front struts are inverted
+2 springs
+2 sway bars
+3 air dam

 

Rock Lobster



9 months ago this was a bone stock, automatic, 1989 GTU with an anemic engine (non functional VDI and aux ports).

We completly tore the car down, just about every nut and bolt and built what you see here. I have had very little time to document the build but i hope this winter to take pics and do some writeup.

First thanks to my friends GooRoo, Damian, and benandersonracing.com it makes all of it worth it to race and build with you guys...

Some build highlights:
- Pineapple Stock Port Series 5 Race motor (stage 3 oil mods). Built from almost all new parts, the only used parts were the rotors and the e-shaft. Wired open VDI and aux ports.
- Pineapple rebuilt series 4 transmission with custom trany mount for auto chassis (1986 gears)
- Stance 8k/6k coilovers
- Stock Sway bars
- Full Corksport 2.5" exhaust with headers
- Rtek 2.0
-Fully rewired. The engine harness, front harness and rear harness were completly removed and new circuits were wired and harnessed from scratch. Only the stock emissions harness was used and half the wires were pulled out of it.
- Depowered 15.1:1 rack.
- Removed A/C
- removed Dash and all equipment underneath
- Fuel tank empty with no driver, full stock glass and steel body panels the car weighs in at 2300lbs.
- All emissions removed
- Bone stock fuel system (no issues and no fuel starvation until down to about 3-4 gal in the tank)
- Miata Torsen Rear end with various gear ratios (4.1, 4.3, and 5.12) is what we will run depending on which track we are at.
- Aluminum flywheel and driveshaft
- 6-pot wilwood front brakes with 2-piece rotors and rs/rz rear brake rotors
-Currently we are running 235 Nitto NT-01 tires on 8.5" wide RPF1s.

 

Subscribed, Nice to see a few more FC's!

 

Great thread, I've seen the 387 FC in person at mid-ohio, It's a well done swap and super clean!
I hope to be in PT soon.

Subscribed.

 

ST is where its at. man that counting points stuff gets old real quick if you ask me!

 

More details on the ST car? My '87 TII is still "under construction" and we're expecting it to end up in ST1.

 

With that being said, counting dollars for replacing cracked downel lands gets real old quickly too. You were making 490hp just to compete in TTU. I think the FC chasis looses out to modern suspension technology, and the corvetts' insane tire width allowance.

The PT format helps people race that have a budget.

 

got the reliability issues worked out now so thats not an issue anymore. yes i do agree the rules dont make up for the technology differences but i do also believe if i were to take the hit for putting larger tires on my car it balance back out better. bigger tires almost always fixes things. they are like the biggest band aid you can throw at an issue lol

I dont thing st costs that much more to race. the only real difference is the tire budget and wearing of expendable parts faster and a LOT more fuel. the chassis build is almost the same just requires a few things to be beefed up to take the forces.

 

Points:
7 - Tires
6 - Suspension (inverted aftermarket shocks and springs)
3 - LSD
5 - Exhaust
2 - Brakes
16 - Weight Reduction (Race Weight is currently 2570 or greater)

Under Free Mods:
"OEM ECU/PCM reprogramming via reflashing or replacement/aftermarket ROM chips or
simple ROM boards (The OEM ECU/PCM box/housing and hardware must be used)."

Since the Rtek is a simple ROM board that in effect reprograms the stock fuel and timing maps, it is free....

 

I like that approach, allowing brakes and LSD of the TII at no points. Technically you could run the North American spec TurboII S5 Aero as it was all base stock for 89-91 turbo cars. You could also run either the stock S4 clutch or the S5 viscous LSD.

BTW guys with the new ruleset we can run a depowered 15:1 rack or really any other ratio rack...(we ran it last year illegally, as i had thought removal of power steering was free when i built the car)

 

It works pretty well, I not only get "free" TII brakes but also an LSD. My original plan was to run the S5 aero but I could not find a front lip anywhere and a new one from MazdaTrix plus the shipping was out of the budget so I rewoked my points to run full weight and add an airdam.

I was under the impression the power steering removal was always free, just a change in steering ratio cost points.

 

So was I! But, apparently not...it is for us based on backdating rules, but it would have to be one of those 20:1 racks as before this year ratio change was illegal. Since you reclassed your pullys are free anyway...so it does not really apply to you...

BTW finally an interesting thread on here. First one in some time....lol

 

What side skirts are on that car?

 

We gotta get SCCAITS to weigh in with his B built (or is it A now?). He has the transmission we all want....

 

How do you like the Rtek? We really need to dump the stock ECU and have limited budget. Are you getting good results without the fuel pressure regulator?

 

Sorry guys, went back to SCCA and built the car to try and win National EP races. Many more cars in the class and much more contingency there.

Haven't even looked at the points as I have no plans to run any NASA events this year. Unfortunately PT is dead in TX and racing yourself sucks. Last NASA event was March 2010.

The car has progressed from ITS - ITE - PTD - PTC - PTB - EP. I plan on staying in EP for awhile as our car counts are good and Mazda/Hoosier both pay very well.

 

My fuel system is bone stock. Pump, regulator everything. I did rewire the pump to see full voltage all the time (nearly 14v all the time, and took the resistor relay system out of the equation). We have a very rough tune in there now we basically just pulled fuel out at the top end to smooth it out and picked up a fair bit of power. I need to do a lot more timing and fuel tuning this spring. I ran stock timing maps last year because i had not had time to get the car to a dyno for half a day.

EDIT: The other thing we changed was the fuel pressure vac switch got removed, thus the stock regulator sees full vacuum all the time now.

 

I don't blame you, but, NASA nationals is at Mid-O again this year as you may know and the fields should be a whole lot larger. The local PT fields are always a crap shoot though...

Good luck either way...

 

Have you seen the 3.8l Buick V6 powered FC that will be running PTD. There is a thread on NoRotors.com. The site seems to be down this morning. I'll post a link when it comes back.

Steve

 

Ummmmm it's the 387 car.

http://www.norotors.com/index.php?topic=4555.0

 

Ugh. So true.

 

+1!!

I ran my legends car in STR2 these last couple seasons in NASA MW (im the orange one). A half page long core rule set with none of those funny "intent" arguements makes me think the next time my FB comes out it'll have ST on the side lol

 

Where would you run the 4.3 or 4.1?

With a stockish tire circumference of 78 inches, the 5.12 is good for 152-166 mph in 5th gear @ 8000 rpm (depending on whether you have the .697, 0.711, or 0.758 gear).

Even on long straights (e.g. California Speedway's 0.6 mile front straight), is that speed achievable in a PTD or ITS car?

The 4.3 will get you 137 mph @ 8000 rpm in 4th....

 

The problem with the math above is that an ITS car would be running a 225/45/15 R6 that is 22.9" in diameter which is about 71.9 inches in circumference. At 8500 RPM and the right 5th gear (.756), your top speed is only 149. The chart is for a 225/45/15 R6 @ 22.9" and 5.12 rear.