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-   -   Autocross: Can a fb compete with Miatas? (https://www.rx7club.com/race-car-tech-103/autocross-can-fb-compete-miatas-863055/)

Kentetsu 09-14-09 11:07 AM

Autocross: Can a fb compete with Miatas?
 
I think there are a few of us doing it, but how common is it?


This is an update from my last race (I'm on Sumitomo HTR tires)

Wow, what a great race this past weekend!!!

Even though the clutch is toast, and we had to be very delicate with it on our starts and that shift into 2nd gear, the car did just fine. We probably could have gained another second or so on the starts with a good clutch, but we still managed to put the fear of God into them.

Here's the kill list (all but a couple of these were on race rubber):

2x Honda S2000
10 out of the 11 Miatas (one was supercharged, with two drivers, I beat one but not the other)
944 Turbo
Mazda MS3
2x BMW Z3
8x rotaries (including an ITA car, and a turbo II)
4x Subaru WRX
2x Subaru STI
VW Corrado

Official results are here: http://furrin.org/Results/tabid/56/a...--9122009.aspx (I'm 98 CSP).

Lots of photos from the event (I'll post a link when I get them uploaded) and a bunch of video that I'll post up if I ever get the time to go through it.

I think we'll be taking a bit of a break while I sort out the clutch, a fuel leak, and install some new front struts (upgrading to race Illuminas from the "stock" Illuminas).

Well, so much for the theory that a 1st gen will never be competetive against the Miatas.




.

Kentetsu 09-14-09 01:06 PM

Photos are up: http://furrin.org/Resources/PhotoGal...0/Default.aspx

mazda6guy 09-14-09 02:49 PM

Ok your post cheered me up. Sometimes I feel like going out and getting a project Miata but then I go into the garage and my FB is staring at me begging for more seat time. Until I know my skills are up I will be autoxing my FB until the wheels fall off! Hopefully I can bring some kill stories and trophies like yours to the forums amd my garage shelf. I was looking at the nationals results and noticed that a FB finshed last in CSP. That is what bummed me out.

Kentetsu 09-14-09 04:47 PM

Last place huh? That is a bummer.

Maybe next year there will be more than one rotary in CSP. :) I'm thinking that the car might be ready for it, as long as I can get the free time needed to travel. Thinking about it though...

Keeble 09-14-09 10:23 PM

shit i'm always the slowest time of the day at the local track =D

i think my car needs a better driver

mustanghammer 09-14-09 10:47 PM


Originally Posted by mazda6guy (Post 9494824)
Ok your post cheered me up. Sometimes I feel like going out and getting a project Miata but then I go into the garage and my FB is staring at me begging for more seat time. Until I know my skills are up I will be autoxing my FB until the wheels fall off! Hopefully I can bring some kill stories and trophies like yours to the forums amd my garage shelf. I was looking at the nationals results and noticed that a FB finshed last in CSP. That is what bummed me out.

Couple of comments.....I know the car and the driver. First, the driver has won 4 Solo II National Championships (1 in DP and 3 in CP) driving a Yenko Singer Corvair. He is a 100 percenter - been to every Solo II Nationals ever held. Has numerious Nationals trophies in DP, CP, EM and AM drving various Corvairs and a V6 turbo powered Formula Ford. He is also an accomplished road racer and campaigns an E Production FB nationally.

The car is prepared for Improved Touring S (ITS) club racing so it is very under prepared for CSP. The chassis and cage on the car are first rate....all spherical bearings, custom watts link (not in the stock location) Koni's, Tri-link etc. The 13B engine is dead stock....has to be in ITS and was not running well at the club race held the weekend prior to Solo II Nationals. IT cars are not competitive in Street Prepared solo II.

I have not spoken to the driver, he is on his way to the Runoffs, I am not sure what happened exactly but I would suspect that he had car issues. Certainly not a driver issue in this case....he is really freaking good!

To the bigger issue here.....yes, I believe an FB can be competitive in CSP. The move to Lincoln Air Park will help allot because the courses will be bigger than what was being laid out at Heartland Park. RX7's have been very competitive in the past when Nationals was at Forbes Field and at Salina....both sites featured big courses. Search for Captain America on this site.....that car was really fast.

I think the formula is a fresh iron apex seal 13B with a weber carb/Sterling, light weight flywheel, 4:88 rear end, 13x9 wheels, Hoosier tires, Koni double adj shocks/struts, a tri-link rear suspension, pan hard bar, Re Speed/ISC/Racing Beat front sway bar...Lots and Lots of seat time and a talented driver.

That said....a Miata would be easier but what would be the point of doing what everyone else is doing:)

Skidtron 09-15-09 03:02 AM

Ya quite easily I might add

Kentetsu 09-15-09 09:44 AM

Hey Mustang, that car was running both a watt's linkage and a tri-link? I always thought it was one or the other? Just curious.

13x9 wheels with the new Hoosier 255s would really be great. Hopefully I can afford something like that in the spring. Trying to keep up with these guys while running cheap tires is a lot of work! :) However, I wanted to get as good as I could on cheap tires before going back to the race rubber (I had a used set last year but they were only good for a couple of events).

jdmsuper7 09-15-09 10:15 AM

Not to be a downer here, but while I think a FB could be a fine regional car its going to take alot to come close to a nationally prepped CSP Miata. Those cars are stupid fast. Just look at the results. At nationals this year, CSP was one of the fastest classes that uses actual cars (yes I know the weather screwed up some of the fastest classes like SSM and SS), but still. Look at the San Diego national. Eventual runner up Schenker beat national SM champ Simyani by almost 2 seconds a run! Even ProSolo, which is certainly not playing to the strengths of a CSP car, Schenker is only losing to 1 SS car and 1 ASP car.

I don't know how light you can get FB legally, but I know that the miatas are in the 1800-1900 lb neighborhood, and most of them are on 275s or 255s. In theory, an 13b would be slightly more powerful than even a 1.8 VVL Miata engine, but I don't know that 10 or 20 hp is going to make a huge difference. I'm not saying you shouldn't try, but you will definitely have your work cut out for you. Prove me wrong! Please! Great driver in the right car, I'm not going to say its impossible.

Kentetsu 09-15-09 11:21 AM

Well, I don't doubt that the competition would be much more fierce at the National level. But keep in mind, I'm currently running $50.00 tires and taking on Miatas on race rubber (not to mention the fact that one of them is supercharged).

I certainly wouldn't expect to walk in and take a win my first year. lol. But it's getting to the point where I'm consistently beating Miatas and S2000 cars (that are obviously not even in my class). Once I get a set of 255 Hoosiers on the car, I think she might have a fighting chance against the more highly prepared cars and better drivers.

I might also consider installing the tri-link that's been sitting on the shelf for a couple of years now, but I'm still not sure if I will. The car already is handling so well, I just have to wonder how much better could it possibly get? Maybe it would be worth the trouble of installation, but I'm just not convinced yet.

And I'm sure that some people will question the quality of the competition that I'm running against. All I can tell you is that we have some very experienced drivers and some amazing cars at our events. But of course, I won't have a genuine comparison until I actually start taking on the guys at the National level. So, maybe we'll see. :) I still have a lot to learn, but I think the car itself is ready for this.

If my new partner works out, then it will probably happen for sure. He's been my best friend for two decades, and is a hell of a driver. His talent seems to be inborn or something, because he doesn't have any experience with competition. But he raced my car with me for the first time last year, and he finished only a second behind me. Best of all, he's got a great garage complete with a lift and air tools. And a vehicle that can tow a trailer. So financially, it would be great if he gets on board with me.

One other thing, I will probably try to stay with the 12a rather than upgrade to a 13b. The 12a is what I've got now, and I've always said that I've never lost a race due to a lack of horsepower. But if something were to happen to my current engine, then I would certainly entertain the idea of an upgrade. Mostly it will come down to my driving, and how much I can learn to improve in that area. The car is definitely more capable than I am at this point. lol. I'm still playing catch-up!

mustanghammer 09-15-09 11:07 PM


Originally Posted by Kentetsu (Post 9496710)
Hey Mustang, that car was running both a watt's linkage and a tri-link? I always thought it was one or the other? Just curious.

13x9 wheels with the new Hoosier 255s would really be great. Hopefully I can afford something like that in the spring. Trying to keep up with these guys while running cheap tires is a lot of work! :) However, I wanted to get as good as I could on cheap tires before going back to the race rubber (I had a used set last year but they were only good for a couple of events).

The Watts Link on this car pivots on the back side of the rearend housing not on the front side like the stocker. It pivots on a fabricated mount that is in the center of the rear end housing . The mounts for the other ends of the links are welded to the body. It is a KC Raceware design that they are using on this car and on their E Production car.

Regarding tires....over the Labor Day weekend I raced my car on Kumho Ecsta V700 235/45X13 tires. I ran them on 7" wide wheels. I have always wanted to try them but was concerned that they might be over-sized for my wheels. Any way....they were AWESOME! Incredible grip. The Tire Rack puts them on sale from time to time so you might want to try them. They would be even better on an 8" or 9" rim. Get them shaved if you order them.

Kentetsu 09-16-09 09:23 AM

Thanks Scott! I wasn't even aware that they had Kuhmos in those sizes. I'll check them out for sure.

Running a 235 on a 7" rim, wow! I would not have expected that to work out for you. Although last year I was using 215 Sumitomos on the stock 5.5" wheels. Lots of sidewall bulge involved. :)

Unevolved 09-16-09 10:24 AM

I love this thread. This has been on my mind a lot lately.

I've got an FB that's getting a 13B-RE swap (got both car and engine for a steal), and it's a project first and racecar second. Recently, I've been looking into how the car would fare as an autocrosser. I know it'll do a lot better than my EM2 Civic. To the best of my interpretation, the car's going to fall in SSM with the -RE under the hood. I know that's like stepping into a heavier weight class by half an ounce, and I've already got a good idea of what I'm going to need to be semi-competitive. But it's good to read threads like this, it gives me some hope. I'm planning on running the widest wheels I can fit under the car and not rub.

Until this thread, I wasn't aware two-way adjustable Konis were an option for this chassis... Anyone care to point me in the right direction? I thought Illuminas were the best we could get.

Regardless, OP, thanks for letting my know my daydreams aren't completely insubstantial.

DamianSoul 09-16-09 12:23 PM


Originally Posted by Kentetsu (Post 9496913)
One other thing, I will probably try to stay with the 12a rather than upgrade to a 13b. The 12a is what I've got now, and I've always said that I've never lost a race due to a lack of horsepower. But if something were to happen to my current engine, then I would certainly entertain the idea of an upgrade. Mostly it will come down to my driving, and how much I can learn to improve in that area. The car is definitely more capable than I am at this point. lol. I'm still playing catch-up!

You're probably right about your skill as a driver being the biggest factor, but I've always felt that a more powerful engine was one advantage that a 13B has over the 1.8. The national prepped Miatas are putting down around 150 RWHP, and they are very fast. I worked one of the faster sections at the Farmington National Tour, and every time Bill Schenker drove by his acceleration uphill was just unreal compared to the local CSP Miatas. The best local prepped CSP Miata weighed in at about 2100 lbs, and it looked quite slow through that section compared to Bill's Miata. Since the FB in CSP trim will probably weigh somewhere around 2100 - 2200 lbs, it seems like the extra horsepower can only help.

A 13B-DEI (S5 six-port) with stock intake (VDI, 6PI, throttle body mod), open exhaust (pre-silenced true dual), tuned with an Rtek ECU put down a consistent 170 - 180 RWHP. I'm not sure what a weber carb will buy you, but I'm curious to see the difference in torque and power curves. I think 190 RWHP might be possible by running 101 octane and leaning out the mixture; however, this is pure speculation since I've never tried it, and 101 isn't cheap (and neither is a blown engine). Either way, peak horsepower doesn't matter too much to me since I don't sit at 8000 RPM for very long if at all.

Kentetsu 09-16-09 12:58 PM

Well, let's just say that if a good 13B dropped out of the sky and landed in my garage, I wouldn't hesitate to throw it in there. But there's a couple of things to keep in mind about this project of mine:

1. I have a wife and 3 kids.
2. This is my daily driver.
3. I work about 60 hours/week.
4. Because of all of the above, I have to be very budget concious.

:)

DamianSoul 09-16-09 02:20 PM


Originally Posted by Kentetsu (Post 9499600)
Well, let's just say that if a good 13B dropped out of the sky and landed in my garage, I wouldn't hesitate to throw it in there. But there's a couple of things to keep in mind about this project of mine:

1. I have a wife and 3 kids.
2. This is my daily driver.
3. I work about 60 hours/week.
4. Because of all of the above, I have to be very budget concious.

:)

I understand; CSP is very expensive so I'm sure each modification requires much justification. Good luck.

Kentetsu 09-16-09 06:28 PM

Thanks DamianSoul

That's also why this project has taken me 9 years to reach the point that it's at. Never enough time. But, it seems to be getting easier each year as the kids get older.

I'll have to get them behind the wheel too in another few years. They're already asking about kart racing. :)

mustanghammer 09-16-09 08:34 PM


Originally Posted by Kentetsu (Post 9499087)
Thanks Scott! I wasn't even aware that they had Kuhmos in those sizes. I'll check them out for sure.

Running a 235 on a 7" rim, wow! I would not have expected that to work out for you. Although last year I was using 215 Sumitomos on the stock 5.5" wheels. Lots of sidewall bulge involved. :)

Yeah I wasn't expecting much either. They were on sale for $91 each and I needed a set to finish the year. I did have to adjust cold pressures down to get a good contact patch.

I had run V700's in the 215/50 x 13 size in the past and liked them. They were not as good as the V710's turned out to be but still a fun tire to drive. But apparently an extra 20mm in tread width makes a huge difference. I was turning really fast lap times and running over the Mustangs, Porsches and Vipers in the twisty bits.

There are several sites I watch on a regular basis. Tire Rack.com is one of them because you never know what you will see. I have gotten deals on Hoosiers and Kumhos in the past on their site. The other place to look is on Hoosier's web site. They are always selling discontinued tires cheap. Sometimes they have DOT's that I can use.

I feel your pain when it comes to a budget. Club racing eats tires like crazy so I am always looking for a deal. I make it my mission to win races on the cheapest tires I can find!!!

jdmsuper7 09-16-09 09:22 PM


Originally Posted by DamianSoul (Post 9499511)
You're probably right about your skill as a driver being the biggest factor, but I've always felt that a more powerful engine was one advantage that a 13B has over the 1.8. The national prepped Miatas are putting down around 150 RWHP, and they are very fast. I worked one of the faster sections at the Farmington National Tour, and every time Bill Schenker drove by his acceleration uphill was just unreal compared to the local CSP Miatas. The best local prepped CSP Miata weighed in at about 2100 lbs, and it looked quite slow through that section compared to Bill's Miata. Since the FB in CSP trim will probably weigh somewhere around 2100 - 2200 lbs, it seems like the extra horsepower can only help.

I've driven one CSP miata and ridden in another, and neither car was fully prepped. I've driven Ed's car (won Finger Lakes Tour) and it is insane. I thought my FC handled well but the miata is just telepathic. Its a 1.8, OTS Konis, the 255/R13 Hoosiers, and I think the springs are in the 700lb/in ballpark. I wish I could describe it adequately, it is simply an instantaneous reaction, and the right reaction at that. The worst part is, this car is 1-2 sec slower than Sho Torri's car, which I've had the pleasure of riding in. That car is another dimension by comparison, and its STILL not completely nationally prepped (I think he was 3-4 sec down on the leaders over 2 runs at nationals, but his co-driver is quicker). I swear they never brake. It seems like no matter what speed it was at, it could do the element easily. I really wish I could convey to you guys how wild these cars are. You have to see them to believe it.

Kentetsu 09-17-09 03:50 AM

No doubt the Miatas are incredible cars. But we look so much better! :)

I always joke that anyone can win in a Miata. Well, more like half joking. lol. I've met several Miata drivers who started out with RX7s, and all I hear is "I loved my car, right up until I drove a Miata for the first time"....

Kentetsu 09-17-09 06:44 AM

4 Attachment(s)
Wish I could find some better photos, but here's a shot of some of my competition. This is the supercharged Miata that I've been sparring with.

Also a couple shots of some other nice cars. I haven't beaten the Lotus on dry pavement yet (turbo, 450 whp), but he's only a couple seconds faster than me. I don't think I'll break into his territory until I get some decent rubber. :)

mazda6guy 09-17-09 06:53 AM

No matter what I respect the Miata. I still see me in the furture becoming a Miata owner and still competing in my RX-7. I lived in Germany for 5 1/2 years and I always wodered why every other German driver owned a Miata. Incredible piece of machinery.

Kentetsu 09-17-09 06:33 PM

No doubt. I would love to have that car (please don't tell my 7). It's like a force fed rollerskate, and a blast to watch. Hell of a nice guy, too. But I must beat that damn Miata! lol.

j9fd3s 09-20-09 03:45 PM


Originally Posted by Unevolved (Post 9499206)

Until this thread, I wasn't aware two-way adjustable Konis were an option for this chassis... Anyone care to point me in the right direction? I thought Illuminas were the best we could get.

.

nope, there is a koni option, and mazdacomp sells bilsteins. i wish i had looked a little longer before i bought my illuminas, for like $100 more i could be bilstein, and we can valve those in house....

jdmsuper7 09-20-09 10:05 PM

As long as we are posting Miata kills, I got 2 SSM ones today, and a viper lol. http://www.phillyscca.com/solo2/index.html hopefully results will be up soon


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