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Since you guys are all into auto x i'd rather ask you

Old 07-12-07, 11:52 AM
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Question Since you guys are all into auto x i'd rather ask you

can anyone help or tell me where can i get a good lsd with a good price i drive a 86 base model n/a and an lsd that only pulls by one wheel
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Old 07-12-07, 12:08 PM
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If you're autocrossing an NA might wanna see if you can get a used miata torsen diff.
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Old 07-12-07, 12:11 PM
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thx
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Old 07-12-07, 12:29 PM
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will i need any custimization and will it slow me down
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Old 07-12-07, 06:02 PM
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Originally Posted by TehMonkay View Post
If you're autocrossing an NA might wanna see if you can get a used miata torsen diff.
That's probably not legal unless you are running in a prepared class.
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Old 07-12-07, 06:54 PM
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Sm?
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Old 07-13-07, 08:04 AM
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Maybe you should say what class you want to run in. An LSD diff. will help alot, but is it worth moving to a non-competive class for??
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Old 07-13-07, 03:10 PM
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If I had an open dif. car I would run in STS2 and prepare to that class (I can't run my '87 GXL because of the clutch type LSD). If you get a good suspension, allignment, and some 7-7.5" rims and 225 tires (azenis/hankooks/bridgestones) you should have none to only a little problem with wheelspin.
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Old 07-16-07, 03:57 PM
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Originally Posted by finky View Post
If I had an open dif. car I would run in STS2 and prepare to that class (I can't run my '87 GXL because of the clutch type LSD). If you get a good suspension, allignment, and some 7-7.5" rims and 225 tires (azenis/hankooks/bridgestones) you should have none to only a little problem with wheelspin.
Are you sure you can't run? I was pretty sure that LSD's of any type are allowed as long as they were original equipment on that car.

By extension of that, I'm pretty sure the rules also state that you can use optional equipment from a different car, as long as you take all of it. Like if the GXL had an LSD and different seats than a base RX7, you can install that LSD and run your car as a GXL as long as you take the seats also. (Although that wouldn't matter for STS2, because you're allowed to change to any reclining seat that weighs 14 lbs or more, I believe, so you would be able to just swap the diff.)
Also, if the LSD was available as an option on a base model car, then you can install it on your car and still be legal.
I'm actually going to be taking advantage of that rule to do the full TII drivetrain swap and run in BSP instead of CSP.

With that being said, I've seen a lot of things racing autocross that AREN'T legal, but noone's ever said anything. For example, STS and STS2 cars can have a replacement seats, so long as they're 14 lbs or more and have an adjustable seatback. Most STS cars I've seen use the little 9lb aluminum non-adjustable buckets. I know of one that has head and valve work, which is pretty much a guaranteed ticket to SM or P class.
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Old 07-16-07, 05:14 PM
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I have a 4.10 NA 2nd Gen LSD. It doesn't have the aluminum cover though and was replaced by a 5.12 for my car. It is in good condition. The loser off ebay that won it a month ago never paid and I have yet to relist. If you want pics let me know, shipping would be about $75 and we'd have to talk diff price.
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Old 07-18-07, 06:23 PM
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Originally Posted by Richter12x2 View Post
Are you sure you can't run? I was pretty sure that LSD's of any type are allowed as long as they were original equipment on that car.

By extension of that, I'm pretty sure the rules also state that you can use optional equipment from a different car, as long as you take all of it. Like if the GXL had an LSD and different seats than a base RX7, you can install that LSD and run your car as a GXL as long as you take the seats also. (Although that wouldn't matter for STS2, because you're allowed to change to any reclining seat that weighs 14 lbs or more, I believe, so you would be able to just swap the diff.)
Also, if the LSD was available as an option on a base model car, then you can install it on your car and still be legal.
I'm actually going to be taking advantage of that rule to do the full TII drivetrain swap and run in BSP instead of CSP.
Clutch type LSDs are illegal (stock or aftermarket). I would have to swap to an open dif and do a few other things to be legal as a total swap to run STS2 with an '87 FC. I could get an S5 GTUs as they have a Viscous type dif and be legal in STS2.
I still think an S4 with open dif would be faster than the heavier S5 with Viscous in STS2. No one has tried it Nationally though. James Wilson campaigned a GTUs a few years ago very well. If you search you can find the old thread that was posted.

You can't do the TII swap you are planning and be legal in BSP. You would have to run SM2 since N/A and Turbo cars are in completely different classes.


As far as rule infractions you can do whatever you want on a local level and usually get away with it but why?? As soon as you start racing in the higher ranks you will get protested very quickly.
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Old 07-18-07, 07:08 PM
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Originally Posted by Richter12x2 View Post
For example, STS and STS2 cars can have a replacement seats, so long as they're 14 lbs or more and have an adjustable seatback. Most STS cars I've seen use the little 9lb aluminum non-adjustable buckets.

As far as seat rule in Street Touring SCCA adopted a new rule on seat weights. The total weight of the seat and brackets has to be 25 LBS. This keeps guys from putting a 15 LBS seat in with duct tape and bubble gum (you may laugh but I have seen a couple STS cars I would not ride in).
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Old 07-19-07, 10:36 AM
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Originally Posted by finky View Post
Clutch type LSDs are illegal (stock or aftermarket). I would have to swap to an open dif and do a few other things to be legal as a total swap to run STS2 with an '87 FC. I could get an S5 GTUs as they have a Viscous type dif and be legal in STS2.
I still think an S4 with open dif would be faster than the heavier S5 with Viscous in STS2. No one has tried it Nationally though. James Wilson campaigned a GTUs a few years ago very well. If you search you can find the old thread that was posted.

You can't do the TII swap you are planning and be legal in BSP. You would have to run SM2 since N/A and Turbo cars are in completely different classes.


As far as rule infractions you can do whatever you want on a local level and usually get away with it but why?? As soon as you start racing in the higher ranks you will get protested very quickly.
Was just glancing through the rulebook, because I was pretty sure on a couple of points - this is what I was going on.

On being legal for BSP -
C. Equipment and/or specifications may be exchanged between different years and models of a vehicle if (a) the item is standard on the year/model from which it was taken, and (b) the years/
models are listed on the same line of Appendix A (Street Prepared Classes). The updated/backdated part or the part to which it is to be attached may not be altered, modified, machined or otherwise changed to facilitate the updating/backdating allowance. Standard factory installation methods, locations, and configurations are allowed. The updating and/or backdating of engines,
transmissions or transaxles must be done as a unit; component parts of these units may not be interchanged.
So it's legal if I take it all and don't mix and match, and I'd move from CSP (NA) to BSP (TII)

On LSD -
L. Limited-slip differential, transmission and differential ratios, clutch
mechanisms and carburetion, fuel injection or supercharger induction
systems must be standard as herein defined.
That's what I was looking at, but I did look further and you're right, only viscous LSDs are allowed in STS/STS2. So no clutch LSD equipped NA Rx7s or Torsen Miatas in STS2. Street-Prepared rules and STX and STU rules allow them, though, and stock rules too, I'm pretty sure.
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Old 07-19-07, 10:54 AM
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Ah, wait - I see what you're saying. The rule says they have to be from the same LINE of the appendix, as in, the same exact class. :P I don't know why I read that to just mean that both the car you're swapping to and the car you're swapping from from had to have a line IN the appendix. (As in, I couldn't swap in a 3 rotor engine on the basis that they were available in another model of Mazda car in Japan, unless it was listed for SCCA rules.)
I could have sworn I read that you could swap any equipment available on different models of the same car, but you had to take all of it and you would run in that car's category. Oh well, I guess I'll be racing with the S2000 club or BMWCCA when I'm done instead of the SCCA.
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Old 07-19-07, 12:49 PM
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double post
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Old 07-19-07, 12:51 PM
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For an example the Miata guys use the rule to run the 1.8s in an early 1.6 chassis' because the line says all N/A miatas. . They could not run the Mazdaspeed Miata turbo engine though because it is on a different line.
Same with the CSP all N/A RX-7 line.
As far as the 3 rotor goes you can run one in SM2. Look up Erik Strelnieks he has a great example of a 3 rotor FD auto X car
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Old 07-19-07, 01:39 PM
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Gotcha, I understand now. That sucks a little, but around here you can get almost 8 runs with the s2000 club for the same price as 3 runs with the SCCA, and pay less money too. I'll miss the friends I've made, but I'll probably go back once a year for the Texas Motor Speedway road course race.
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