SU Rule Changes

[Fusion Works]

For what it's worth, here is the response that I forwarded to Mark for everyone's consideration:

PROPOSED Street Unlimited Class Rules

A. Chassis


6. Factory firewall may be modified to allow for the roll cage to continue into the engine bay, for service related reasons, and for fitment of alternate engine and transmission. These modifications are limited to the minimum required to accomplish the above and firewall must be resealed to provide an adequate level of safety in the event of an engine bay fire. I think this is a slippery slope here. I can’t really think of a reason why a roll cage would need to enter the engine compartment to facilitate an engine swap. Either we allow roll cage bars in the engine compartment or we don’t.

I like my legs intact and as fast as some of these cars are/could be, having a proper racing cage should not be rule limited. If you have a car that makes 400-600hp, you are going to be going as fast as many race cars. Having the ability to have the roll cage through the firewall will add another line of defense to protect the driver's legs in the event of a collision, or an off track event. Not saying you have to, but having the ability within the rules makes perfect sense. We aren't talking IT or SP cars, some of you guys are GT car fast.

[Fusion Works]

I agree with keeping simple as well. My only caution is the current approach runs counter to all the other rulesets so it seems to be begging for confusion. All that is needed is a sentence at the beginning stating that anything is allowed other than the listed set of limitations.

Hey now, we don't need and Street Prepared interlopers messing with our rules.

[e30Racer]

Here are some answers back to give you an idea of what is behind some of the rules if they weren't clear to begin with.

PROPOSED Street Unlimited Class Rules

A. Chassis

1. Vehicles must be mass production road going vehicles constructed by a recognized manufacturer and currently/previously available as a factory OEM vehicle with a government mandated VIN# or equivalent. Vehicles must have the ability to be registered legally for street use. Tube chassis, open wheel or club racer cars that may be made street legal are not allowed. (i.e. Radical SR3, Factory 5 818, Ultimate GTR, Aerial Atom, etc.) We may want to consider re wording this. What if someone has a JDM vehicle that doesn’t have a government issued “VIN”? That is why the rules also include "equivalent." If you import a JDM or foreign car, then so long as it can be properly registered for street use, the car will be allowed.

3. The OEM floor pan and shock tower location (or shock location equivalent if not equipped with shock towers) must remain intact and unmodified.

4. All vehicles must have a silhouette that is largely faithful to the original with the general body shape and outline remaining largely true to the original stock body. Not really sure what you are trying to accomplish here.This keeps people from pulling a Robert Russom and totally chopping a car down to the frame and a roll cage. Additionally, it keeps people from completely cutting off the body and then replacing it with a "shell" that looks nothing like what the car originally was. This keeps the cars more in their "production" form.

6. Factory firewall may be modified to allow for the roll cage to continue into the engine bay, for service related reasons, and for fitment of alternate engine and transmission. These modifications are limited to the minimum required to accomplish the above and firewall must be resealed to provide an adequate level of safety in the event of an engine bay fire. I think this is a slippery slope here. I can’t really think of a reason why a roll cage would need to enter the engine compartment to facilitate an engine swap. Either we allow roll cage bars in the engine compartment or we don’t. I think you're reading this wrong. The factory firewall may be modified for any of the reasons above, not that it must be for all of the reasons. As Brett stated above, a roll cage may penetrate the firewall to make the car more safe, even if you don't have an engine swap. Likewise, the firewall may be cut and bent a little to fit a different engine even if the roll cage doesn't go into the engine compartment.

7. At a minimum, safety equipment must meet the requirements in the current SCCA Time Trial Rules for Track Trials and Hill Climbs. The SCCA Time Trial Rules covers information regarding roll bars/cages, fire protection, driver restraint/protection, etc. Pretty sure this is already covered in the GCR, no need to re mention here. The GCR does not cover TT safety equipment unless the car is running in a GCR class. SU is not a GCR class. Also, it makes it much easier when someone is looking up rules to have everything pretty much located in one place. By having this information, we are at least pointing drivers to the location where they can find the information regarding driver and car safety requirements.


C. Exterior/Aero

2. Wings and/or spoilers may be used and are unlimited. However, a wing or spoiler may not protrude more than 6 inches beyond the side or rear bodywork of the vehicle. Active Aero is prohibited. Is it really necessary to restrict “Active Aero”? Yes I believe it is. Although no one is currently running it, we think it's necessary to prohibit and provide a clear rule against it.

6. OEM front and rear shock towers must remain intact. All vehicles must use the OEM front and rear shock towers in the OEM locations. Shocks/struts must attach to these towers and must pass through the original hole in the towers. The shock tower may be modified to install shock mount reinforcement, spacers, or camber/caster plates, but the OEM structure must remain in place. On some vehicles, it is necessary to move the holes or re-drill them to bolt on certain caster/camber plates. These rules are not prohibiting a person from drilling new holes. The shock tower may be modified for the installation of camber/caster plates.


D. Engine/Drivetrain/Fuel

1. Engine Swaps are open. If an engine and or transmission swap is performed, the new engine and transmission should be installed close to the OEM engine and transmission location. Engine swaps are to be of the same configuration (Front-engine to Front-engine, Rear-engine to Rear-engine). Turbocharging and supercharging are allowed. Differentials and gearing ratios (transmission or differential) may be changed. If someone is going through the trouble of an engine swap, why should we restrict them to moving the engine farther backwards? Remember, you already covered leaving the floor structure OEM (which should include the trans tunnel)-so if there is some free space available-why should we restrict that? It doesn't restrict that. What it does is restrict someone from totally moving the firewall back in order to place the engine basically inside the passenger compartment. The engine must be "close" to the OEM location.

2. Exhaust must exit behind the centerline between the front and rear axle. The exhaust tips may not extend further than 3 inches beyond the bodywork. I think we should add something about waste gate dumps. It’s something that isn’t really talked about in the GCR. I think they should be allowed as long as they are pointed towards the ground and the earliest point possible from the turbo. Definitely something to consider.

3. Unleaded gasoline and E-85 are the only fuels permitted. What if someone wants to use methanol injection to help with detonation? Valid point. We'll look into it and see if we could adjust for that.


E. Suspension/Brakes/Tires/Wheels

3. Aftermarket active suspension is prohibited. Vehicles with OEM semi-active or active suspension are permitted to use the OEM system in an unmodified form. How would you go about enforcing this? By looking for an aftermarket controller, or taking the stock controller to a dealer/shop that could read it and check to see if the controller was not longer within OEM specs

5. All tires must be available to other SCCA Time Trial competitors in the Street Unlimited Class for purchase. If any tires are found to be of a cheater compound the competitor will be disqualified and no refund will be issued. I don’t think this is really necessary. How would you test for this? take a durometer reading and see if the tire compound is outside of the normal range for that tire. There is always some variation, but if the tire compound is significantly softer than other tires of the same compound, you could make that determination.

6. Upper 1/4 of the wheel and tire may not extend past the widest point of the wheel arch when viewed from above. I think it would make more sense to have a tire size rule based on drive train layout then it would to try and judge something like this. I disagree. Making a tire size rule would be very difficult for a class of this sort. You could have anything from a miata (RWD) to a viper (RWD) and there rear wheel sizes are extremely different. Additionally, the rules allow for adding on fender flares, which could drastically change the width of a wheel and tire a person could run. If someone were to take a miata and put on a widebody kit that increased the width on each side by 3-4 inches, then what would be the point if they could still only run 7" rims because that is what fits under a stock miata body? The point of this rule is to keep the wheel and tires actually tucked within the bodywork. Without this rule, you could have a miata running 13" wide tires that are sticking outside of the bodywork of the car by 6 inches on each side. That creates a safety hazard if everyone is running around with tires sticking outside the bodywork. Just watch what happens when formula car get together and their tires touch....car's tend to leave the safety of the ground.

[e30Racer]

Sounds like we borrowed heavily on the rules from Global Time Attack.

Does this rule out Locost 7 Type cars?

Leave the aero rules alone or add an exclusion for hatchbacks if you change the rule regarding mounting height. We can't easily put a hatch back wing below the hatch and still have the 6in extension rule met.

Can we pull the rule about where exhausts exit? This excludes hood dump or front fender dump for a turbo car. Everyone likes to see flames shooting out of their race car.

Yes these rules would rule out Locost 7 type cars.

We won't be adding back in the aero rules regarding height and roof line. Hatchbacks will be good to go.

What about the safety aspects to having exhaust dump in front of the driver? We kept the limitation for the exhaust to dump behind the driver so as to limit the chance of the driver breathing in exhaust fumes.

[87RX7RACER]

See my responses in red below:

Here are some answers back to give you an idea of what is behind some of the rules if they weren't clear to begin with.

PROPOSED Street Unlimited Class Rules

A. Chassis


4. All vehicles must have a silhouette that is largely faithful to the original with the general body shape and outline remaining largely true to the original stock body. This keeps people from pulling a Robert Russom and totally chopping a car down to the frame and a roll cage. Additionally, it keeps people from completely cutting off the body and then replacing it with a "shell" that looks nothing like what the car originally was. This keeps the cars more in their "production" form. While it may keep this from happening, you should consider the wording here as it leaves a lot of room for interpretation. "Largely faithful" can mean different things to different people. It would be easier to have something that says "vehicle's bodywork should be representative of the cars actual model and the production uni-body materials shall remain intact"

6. Factory firewall may be modified to allow for the roll cage to continue into the engine bay, for service related reasons, and for fitment of alternate engine and transmission. These modifications are limited to the minimum required to accomplish the above and firewall must be resealed to provide an adequate level of safety in the event of an engine bay fire. I think you're reading this wrong. The factory firewall may be modified for any of the reasons above, not that it must be for all of the reasons. As Brett stated above, a roll cage may penetrate the firewall to make the car more safe, even if you don't have an engine swap. Likewise, the firewall may be cut and bent a little to fit a different engine even if the roll cage doesn't go into the engine compartment. Again, if it's for safety and we want it to be included it should be added without the mention of a motor swap.

C. Exterior/Aero


6. OEM front and rear shock towers must remain intact. All vehicles must use the OEM front and rear shock towers in the OEM locations. Shocks/struts must attach to these towers and must pass through the original hole in the towers. The shock tower may be modified to install shock mount reinforcement, spacers, or camber/caster plates, but the OEM structure must remain in place.These rules are not prohibiting a person from drilling new holes. The shock tower may be modified for the installation of camber/caster plates.I mis-read this orignally, but what if you want to make the hole bigger to facilitate more caster (moving the shock backwards)? As an example, my RX7 would not be legal if this wording was to stay as written.


D. Engine/Drivetrain/Fuel

1. Engine Swaps are open. If an engine and or transmission swap is performed, the new engine and transmission should be installed close to the OEM engine and transmission location. Engine swaps are to be of the same configuration (Front-engine to Front-engine, Rear-engine to Rear-engine). Turbocharging and supercharging are allowed. Differentials and gearing ratios (transmission or differential) may be changed. It doesn't restrict that. What it does is restrict someone from totally moving the firewall back in order to place the engine basically inside the passenger compartment. The engine must be "close" to the OEM location. Again, you've already said in another rule that modifying the firewall for anything other than roll bars wouldn't be legal. So if you install another engine in the car and you happen to have extra room to slide the engine back for better weight transfer, you should be allowed to do so IMO.


E. Suspension/Brakes/Tires/Wheels

6. Upper 1/4 of the wheel and tire may not extend past the widest point of the wheel arch when viewed from above. I disagree. Making a tire size rule would be very difficult for a class of this sort. You could have anything from a miata (RWD) to a viper (RWD) and there rear wheel sizes are extremely different. Additionally, the rules allow for adding on fender flares, which could drastically change the width of a wheel and tire a person could run. If someone were to take a miata and put on a widebody kit that increased the width on each side by 3-4 inches, then what would be the point if they could still only run 7" rims because that is what fits under a stock miata body? The point of this rule is to keep the wheel and tires actually tucked within the bodywork. Without this rule, you could have a miata running 13" wide tires that are sticking outside of the bodywork of the car by 6 inches on each side. That creates a safety hazard if everyone is running around with tires sticking outside the bodywork. Just watch what happens when formula car get together and their tires touch....car's tend to leave the safety of the ground.Ok, if the only intent is to make sure that people don't have tires protruding past bodywork, wouldn't it be easier to just say that the tire should be covered by bodywork? Some people may chose to run crazy camber and then you get into a judgment call sort of thing. The rule should be direct and to the point. "Wheels shall not protrude past the bodywork of the car. If fender flares are used then said flares should cover the tire when viewed from above."

[87RX7RACER]

What about the safety aspects to having exhaust dump in front of the driver? We kept the limitation for the exhaust to dump behind the driver so as to limit the chance of the driver breathing in exhaust fumes.

If you have a properly sealed firewall, there should be little to no chance of exhaust fumes entering the driver's compartment IMO. Personally, it would be the same thing as driving a car with extremely leaking header. A leaking header is not talked about in the GCR so why would a waste gate dump be automatically excluded because of this.

My Evo had an externally vented wastegate dump and nothing was said about it. There are a lot of other cars in other clubs that have the same setup and they are allowed to run them as well with no issue.

[Fusion Works]

What is wrong with leaded fuel? 110octane is a leaded fuel? You have effectively just limited most people to what ever fuel is found at a gas station. No refills at the track as most tracks carry 110 leaded race fuel. That change needs to be examined closely. If you are going to allow people to run E85 with its 104-113 octane, you are automatically hurting the people who won't run E85. I get the no methanol, and things like that, but forcing unleaded fuel would hurt motor durability thus raising costs and cutting participation. I don't want to deal with the problems associated with E85.

[zukitek]

I think requiring the exhaust to exit the body work would be sufficient as most other GCR class rules require.

As to fuel we just need to require gasoline and e85 and leave leaded or unleaded up to the racers. I don't run race fuel since it is pretty hard on wideband 02 sensors but no reason I can think of to rule out leaded fuel.

[e30Racer]

I see everyone's point of the exhaust exiting the bodywork. And as long as the safety concerns are met, then I have no issue with it. The other factor that I just thought of, but which we didn't include really, is that the exhaust must meet the sound dB levels as per the TT rules or individual track rules. This factor in many cases would require the addition of mufflers/silencers/etc which may require the exhaust to run more distance than just out of the fender.

What about saying something like "Exhaust may exit out of the front fender on the side opposite of the driver. Sound levels must be under SCCA required levels, or the levels as stated by track management."

Or should it be even more "unlimited" than that?

[Fusion Works]

Yeah, but you have 6.0 of American Fury to make you 9 million HP. I have 1.6 litres of rice to get it done. It would have a hard time putting an LS2 in my car. Boosted cars should have a measure of security and not have to rely on pump fuel to keep their motors alive.

I would go with a regular gasoline (to included leaded and unleaded) and E85 rule. That would keep things like Methanol and Nitromethane, and such out, (because that is such a problem?)

[Fusion Works]

I see everyone's point of the exhaust exiting the bodywork. And as long as the safety concerns are met, then I have no issue with it. The other factor that I just thought of, but which we didn't include really, is that the exhaust must meet the sound dB levels as per the TT rules or individual track rules. This factor in many cases would require the addition of mufflers/silencers/etc which may require the exhaust to run more distance than just out of the fender.

What about saying something like "Exhaust may exit out of the front fender on the side opposite of the driver. Sound levels must be under SCCA required levels, or the levels as stated by track management."

Or should it be even more "unlimited" than that?

Why not just leave the old rule. Must meet sound regs, don't really care how you do that. Who cares where it exits? If the car is moving you won't get asphyxiated. LOL

[e30Racer]

Regarding the firewall issue. The firewall may be modified for a roll cage to go through it and attach to the frame, or shocktowers, or whatever else you want to attach it to. The firewall may also be modified for the installation of a new engine/transmission, so long as its only modified to the minimum point necessary. The firewall may also be modified for maintenance reasons. If you want to cut a little trap door so you can easily get to a drain plug that is otherwise located in an extremely difficult position, then you can do that so long as the "door" is sealed when its shut. There is nothing that links the roll cage and motor swap together. Or vice versa. They are all independent of each other.

[e30Racer]

I just want to reiterate again to everybody, THANK YOU for taking the time to discuss these changes and to give your thoughts. As part of the leadership team for SEDIV TT, we are working on y'alls behalf. And your input is vital because we only want to do what our members want....so long as it's within reason haha. So please keep the discussion going as long as you'd like. My feelings are not being hurt by any criticisms, and I am not intending to hurt anyone else's. Share your thoughts and ideas. I am trying to respond to give some framework for what we did and why. But that in no way means that it is the best or only way. There have already been some things that will be addressed for the final proposed rule changes, so y'all are having a positive impact already.

Thanks again everyone!

[RoccoB]

Damnit, there go my plans for a direct port 100 shot of nitrous to help me pass Ricky in the straights.

[e30Racer]

It's not cheating until you get caught......