RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   Race Car Tech (https://www.rx7club.com/race-car-tech-103/)
-   -   FC's in NASA PT (https://www.rx7club.com/race-car-tech-103/fcs-nasa-pt-937900/)

RockLobster 01-24-11 09:50 AM

There are actually some tracks where a 4.10 using 2nd-4th is faster than a 5.12 using 3rd-5th. It just depends. I did find out quickly that the 4.3 is a fairly useless ratio for road racing.

We use a whole acceleration rate calculator based on the tire circumference and compare with log data etc.

wlfpkrcn 01-24-11 01:29 PM

I just built a 4.77 with torsen. We have not had a chance to run it yet

SCCAITS 01-24-11 03:59 PM


Originally Posted by wlfpkrcn (Post 10432563)
I just built a 4.77 with torsen. We have not had a chance to run it yet

4.88 maybe? Where's a 4.77 come from?

On another note, tough to have a front running ITS car and class well in PT. The ITS setup needs the .756 5th which is +3 in PT for altered gear ratios.

On a PT only car, rather than take +3 for changing the 5th gear, might consider an Emco gearset for the RX-7 box and skip the high dollar 5.12 or 4.88 rear end. You'd have a close ratio transmission and only +3. I saw one for sale a few months back for around $2k in good shape.

Quaife 2 - 2.564 1.670 1.277 1.000 0.794
Quaife 1 - 2.350 1.550 1.240 1.000 0.886

wlfpkrcn 01-24-11 04:28 PM

4.77 came out of a Kia Sportage . We picked it up for $200 with a Torsen. I had Rebello lengthen the pinion.

wlfpkrcn 01-24-11 04:43 PM

I also agree that a proper ITS car cannot be a competitive PT car. A proper ITS car will end up in PTC. More importantly for us is the ITS car falls into E2. The idea of having a car you can only race with NASA did not make sense. I was not able to find a way to make the car maximized race with both sanctioning bodies. We were mainly interested in enduros so the decision was made to go the ITS route. Not sure a proper ITS car will be faster than a proper "D" car.

Currently we still fall into D so it's not a problem. Once we get a ECU, fuel pressure regulator we will be done in D. I can't remember what else we are short currently from a full build IT car.

RockLobster 01-24-11 05:09 PM

Yep, i'm running an 86 5th gear, its of course not ideal, which is why we find a trade off between 4:10 and 5:12. Otherwise with that GTUs 5th it would likely be a no brainer with a 4.88 or 5.12. I'm gonna check out those emco gears.

SCCAITS 01-24-11 07:27 PM


Originally Posted by wlfpkrcn (Post 10432936)
4.77 came out of a Kia Sportage . We picked it up for $200 with a Torsen. I had Rebello lengthen the pinion.

That should work well, nice find.


Originally Posted by RockLobster (Post 10432988)
I'm gonna check out those emco gears.

Here's the ones I have seen for sale:
http://prodracing.com/prodcar/viewtopic.php?f=4&t=11732
http://prodracing.com/prodcar/viewtopic.php?f=4&t=12004


AWR has it listed as a Quaife gear set: http://store.awrracing.com/products/...tio-Set-1.html

23Racer 01-25-11 02:21 PM

1 Attachment(s)
This is our little toy. It runs in GT4 in CASC GT Challange racing and used to run in the Castrol Touring Car Championship. The specs are as follows;

Motor -

- 1/2 bridge S5 4 Port with S5 NA internals
- 4 ITB intake
- Megasquirt ECU
- Racing Beat Race Header
- 3" Exhaust with Borla Muffler

Suspension -

- presently using coilover Bilstein race valved struts and Koni rears. Converting to Morrisdamper 3 way adjustables front and rear
- rates vary between 400 - 700 front and 175 to 400 rears
- Suspension Techniques bars front and rear
- poly bushings and rods ends everywhere possible
- Camber plates on front
- alu rear subframe mounts
- rear camber adjustment rod

Brakes -

- stock brake system with Vortex Brakes VR1 and VR2 pads
- braided lines

Body -

- AWR E Prod nose
- APR rear wing

The car has tons and tons of other structural changes and lightening efforts. The seat has been moved closer to the center of the car and lower down to improve C of G. The car has been raced for over 10 years and this season will be back in the GT Challenge Series and the new CASC Time Attack Series.

Eric

Weed Wacker 01-25-11 02:53 PM


Originally Posted by Dan Unk (Post 10416740)
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.

What PT class would you be and what car do you have? Between the 2 FC's, the miata, integra, etc., PTD might be huge! Especially at crossovers!

j9fd3s 02-14-11 01:21 PM


Originally Posted by wlfpkrcn (Post 10432956)
I also agree that a proper ITS car cannot be a competitive PT car. A proper ITS car will end up in PTC. More importantly for us is the ITS car falls into E2. The idea of having a car you can only race with NASA did not make sense. I was not able to find a way to make the car maximized race with both sanctioning bodies. We were mainly interested in enduros so the decision was made to go the ITS route. Not sure a proper ITS car will be faster than a proper "D" car.

Currently we still fall into D so it's not a problem. Once we get a ECU, fuel pressure regulator we will be done in D. I can't remember what else we are short currently from a full build IT car.

do the Rtek and its no points! and just skip the FPR, you don't need it

its also legal in IT

j9fd3s 02-14-11 01:26 PM


Originally Posted by Weed Wacker (Post 10434843)
What PT class would you be and what car do you have? Between the 2 FC's, the miata, integra, etc., PTD might be huge! Especially at crossovers!

this weekend we actually switched from Honda Challenge to PT and TTE (time trials), because the field is bigger in PT in our region.

we took the wing off the HC2 car, and its PTE/TTE. We now own the TTE lap record at Infineon, 1.56.2 i think?

PTE is tough, it lets you build a FAST miata...

wlfpkrcn 02-14-11 02:14 PM


Originally Posted by j9fd3s (Post 10469161)
this weekend we actually switched from Honda Challenge to PT and TTE (time trials), because the field is bigger in PT in our region.

we took the wing off the HC2 car, and its PTE/TTE. We now own the TTE lap record at Infineon, 1.56.2 i think?

PTE is tough, it lets you build a FAST miata...


I have your classification form here. Were you legal? I didn't make it out this weekend.

What HC were you? Must not be HC2, although it looks like all the HC entries are going to be down this year.

j9fd3s 02-14-11 06:05 PM


Originally Posted by wlfpkrcn (Post 10469272)
I have your classification form here. Were you legal? I didn't make it out this weekend.

What HC were you? Must not be HC2, although it looks like all the HC entries are going to be down this year.

of course we're legal! mario added up all the points! feel free to come over and look at it

the car was an HC2 car in 2009, i think they have changed some rules, so i'm not sure what it fits in HC anymore, and since nobody is running HC this year, we decided to do PTE/TTE instead.

wlfpkrcn 02-14-11 06:55 PM


Originally Posted by j9fd3s (Post 10469661)
of course we're legal! mario added up all the points! feel free to come over and look at it

the car was an HC2 car in 2009, i think they have changed some rules, so i'm not sure what it fits in HC anymore, and since nobody is running HC this year, we decided to do PTE/TTE instead.

At this point I'm good. Start kicking every bodies butt and I'll be by

kurtf 02-15-11 12:50 AM


Originally Posted by j9fd3s (Post 10469161)
this weekend we actually switched from Honda Challenge to PT and TTE (time trials), because the field is bigger in PT in our region.

we took the wing off the HC2 car, and its PTE/TTE. We now own the TTE lap record at Infineon, 1.56.2 i think?

PTE is tough, it lets you build a FAST miata...

And either you have a equally fast twin car or you still have 2 transponders from the 25. You guys got me by a couple of tenths in TT on Sunday. Good to see Mario racing in PT again.

Kurt
PTE/TTE/ITA/ITX #76
Blue first-gen

j9fd3s 02-15-11 11:29 AM


Originally Posted by kurtf (Post 10470279)
And either you have a equally fast twin car or you still have 2 transponders from the 25. You guys got me by a couple of tenths in TT on Sunday. Good to see Mario racing in PT again.

Kurt
PTE/TTE/ITA/ITX #76
Blue first-gen

lmao, yes we have the two transponders, it totally confused timing, but just on sunday

you and your car ran good this weekend, good race!

RockLobster 02-18-11 04:20 PM

We are hoping to be at the autobahn and mid-o crossovers this year. Also will be at RA and running enduros if my drivers can cough up enough cash! lol

RockLobster 03-02-11 04:32 PM


Originally Posted by j9fd3s (Post 10470724)
lmao, yes we have the two transponders, it totally confused timing, but just on sunday

you and your car ran good this weekend, good race!


LOL we did that in an MX-5 cup race. Rented a car that had a VERY hidden transponder so we put a battery powered one in for first practice to make sure. And sure enough we got called to race control. I swear they were stifling laughs. I could just read it on their faces, "Bunch of amateurs."

wlfpkrcn 04-01-11 04:24 PM

My BIL took it out for an open track event today at Thunderhill. Stuck it on the dyno. I knew it was down on power... 140hp/124ftlb.

088 04-02-11 01:53 PM


Originally Posted by wlfpkrcn (Post 10548449)
My BIL took it out for an open track event today at Thunderhill. Stuck it on the dyno. I knew it was down on power... 140hp/124ftlb.

140 hp @ Kevin's dyno at MCE? I'm at 138 hp @ Tom McCarthy's dyno in Fremont (which supposedly agrees with Kevin's to within 1%).

So we should race in PTF. ;)

wlfpkrcn 04-02-11 05:45 PM

http://i969.photobucket.com/albums/a...s/RX7_Dyno.jpg

wlfpkrcn 04-02-11 05:47 PM

My BIL had texted me 140. I guess he was a little off. 139.99 :blush:

wlfpkrcn 04-02-11 05:53 PM


Originally Posted by 088 (Post 10549734)
140 hp @ Kevin's dyno at MCE? I'm at 138 hp @ Tom McCarthy's dyno in Fremont (which supposedly agrees with Kevin's to within 1%).

So we should race in PTF. ;)

I would like to lose the the lead out of the car. Currently we have 150# to make 2800. ITS weight is 2680.

SCCAITS 04-02-11 07:52 PM


Originally Posted by wlfpkrcn (Post 10549969)
I would like to lose the the lead out of the car. Currently we have 150# to make 2800. ITS weight is 2680.


SCCA just gave me another 50lb drop off my base weight :nod: Now only at 2250 with a stock gear box, 2363 with the Jerico.

It's a joke that NASA is at 2800. You can't make that without lead and are maxed at 250lbs.

wlfpkrcn 04-02-11 09:11 PM

Only reason we have that little is I'm a fatty


All times are GMT -5. The time now is 04:09 AM.


© 2024 MH Sub I, LLC dba Internet Brands