D_Eclipse9916 Posted December 15, 2015 Share Posted December 15, 2015 Greg, Looking up the history of the -.2 side exhaust rule through the rocker, it seems as though it was put in place for "performance advantage" of running lower. I think with recent rules changes in GTS, many will be planning to head over to ST including myself. The aero penalty makes sense, but wouldn't a "running lower" or "clean up underbody" be under an aero performance advantage? It seems the rule may be out of date, and seems silly that it has a "penalty" just as much as a full PDK or DCT car which in my experience is a much higher advantage than a flat undertray vs semi-flat undertray (with exhaust). It also penalizes a couple GTS guys in other ways. For one, my car has a section of the floor pan modified for the pedals. For an E46 this is no advantage, but I would be hit with this penalty over my peers for 0 advantage. Warts? might just have to deal with it, but doesnt make sense to turn people away for something that is already covered under Aero. Another GTS person going ST this next year has a v8 swap and unfortunately bumped the firewall up a bit to clear his exhaust so would be hit with that as well. Since we are already past the 2016 ruleset, I was hoping to get an answer from Greg on his opinion why it still exists which still may be valid and is not currently already covered under "aero". Quote Link to comment Share on other sites More sharing options...
brkntrxn Posted December 16, 2015 Share Posted December 16, 2015 Greg, Looking up the history of the -.2 side exhaust rule through the rocker, it seems as though it was put in place for "performance advantage" of running lower. I think with recent rules changes in GTS, many will be planning to head over to ST including myself. The aero penalty makes sense, but wouldn't a "running lower" or "clean up underbody" be under an aero performance advantage? It seems the rule may be out of date, and seems silly that it has a "penalty" just as much as a full PDK or DCT car which in my experience is a much higher advantage than a flat undertray vs semi-flat undertray (with exhaust). It also penalizes a couple GTS guys in other ways. For one, my car has a section of the floor pan modified for the pedals. For an E46 this is no advantage, but I would be hit with this penalty over my peers for 0 advantage. Warts? might just have to deal with it, but doesnt make sense to turn people away for something that is already covered under Aero. Another GTS person going ST this next year has a v8 swap and unfortunately bumped the firewall up a bit to clear his exhaust so would be hit with that as well. Since we are already past the 2016 ruleset, I was hoping to get an answer from Greg on his opinion why it still exists which still may be valid and is not currently already covered under "aero". Having owned Mustang Cobras prior to the Corvettes, a side exhaust IS a performance advantage when considering the heat associated with over the axle exhausts. Transmission, differential, and gas tank temps are all subjected to heat with stock routing. I have had each of those items get too hot while on track with the Cobra's. Melting diff bushings and boiling gas (vapor lock) always ends a session prematurely. My .02, I cannot speak for Greg's opinion. Quote Link to comment Share on other sites More sharing options...
ILIKETODRIVE Posted December 16, 2015 Share Posted December 16, 2015 Having owned Mustang Cobras prior to the Corvettes, a side exhaust IS a performance advantage when considering the heat associated with over the axle exhausts. Transmission, differential, and gas tank temps are all subjected to heat with stock routing. I have had each of those items get too hot while on track with the Cobra's. Melting diff bushings and boiling gas (vapor lock) always ends a session prematurely. That reads more like "reliability" advantage and "safety" advantage vs "performance" advantage. Quote Link to comment Share on other sites More sharing options...
D_Eclipse9916 Posted December 16, 2015 Author Share Posted December 16, 2015 Having owned Mustang Cobras prior to the Corvettes, a side exhaust IS a performance advantage when considering the heat associated with over the axle exhausts. Transmission, differential, and gas tank temps are all subjected to heat with stock routing. I have had each of those items get too hot while on track with the Cobra's. Melting diff bushings and boiling gas (vapor lock) always ends a session prematurely. That reads more like "reliability" advantage and "safety" advantage vs "performance" advantage. Reliability is a performance advantage I realize, but is that really worth the same as a DCT/PDK transmission?? Seems pretty wild. I just think it's an old rule covered under Aero for ST3. Quote Link to comment Share on other sites More sharing options...
Bnjmn Posted December 16, 2015 Share Posted December 16, 2015 You will also need a waiver of the trans tunnel mod commandment. I don't see an issue with leaving the rules in place and adding a carve-out permitting holes in the trans tunnel for exhaust and then just routing the exhaust out through a hole in the door. Quote Link to comment Share on other sites More sharing options...
hispanicpanic Posted December 17, 2015 Share Posted December 17, 2015 I'm with the OP on this one. I think all of the rules need a serious look-through as most of it seems outdated and archaic. These rules are supposed to be made not to specifically call out single makes and vehicles. If this rule was in place to penalize a reliability gain in a corvette, then this violates the foundation of the rule philosophy. My turbocharged evo has similar fuel consumption rates as a vette and vapor lock is non existant. My fuel tank saddles the exhaust pipes too. It just isn't a "thing". Of all the imports i've had the opportunity to build/race, never has vaporlock been an issue. So again, why is the side exit exhaust penalized? Rule makers need to take a serious look through on this. Because fundamentally, if there is no serious aero advantage provided by having side exit exhausts, then this rule shouldn't be a rule. If there IS an aero advantage provided by side exit exhausts, then it needs to lumped into AERO and have that categories points adjusted accordingly. If there is a power advantage provided by side exit exhausts, then this mod factor needs to dissappear as power is accounted for anyways. That's like penalizing someone for running aftermarket intakes. I feel like a politician here trying to lobby for repealing a law that still allows you to legally shoot and kill an indain so long as you're inside a covered wagon. Yes, that's still a law in many states. Quote Link to comment Share on other sites More sharing options...
D_Eclipse9916 Posted December 17, 2015 Author Share Posted December 17, 2015 So again, why is the side exit exhaust penalized? Rule makers need to take a serious look through on this. Because fundamentally, if there is no serious aero advantage provided by having side exit exhausts, then this rule shouldn't be a rule. If there IS an aero advantage provided by side exit exhausts, then it needs to lumped into AERO and have that categories points adjusted accordingly. If there is a power advantage provided by side exit exhausts, then this mod factor needs to dissappear as power is accounted for anyways. That's like penalizing someone for running aftermarket intakes. Said much better than I could. I will save this and send to Greg for possible 2017 improvements. Unless he can make an exception for 2016 Quote Link to comment Share on other sites More sharing options...
National Staff Greg G. Posted December 17, 2015 National Staff Share Posted December 17, 2015 I just had a 6 point, detailed post, and it somehow got deleted when I was about to post. Here are the bullets: 1) This has nothing to do with Corvettes that I know of. 2) This is a benefit to those with the modifications already, because otherwise they take the -0.4 Non-Production Mod Factor 3) The -0.2 is only 60 lbs for a 3K vehicle. 4) If someone has these mods, and doesn't think there is a performance advantage worth 60 lbs, then re-route the exhaust back under the floor and under the rocker panel. 5) If it is potential performance advantage for lowering the vehicle for direct handling effects of both lowering the center of gravity and for aero purposes (especially when additional aero mods are added), and there is no Mod Factor for it, then it basically becomes a required modification for everyone who wants to be competitive. NASA does not want this to become a "required" modification. 6) Too much discussion of this issue is likely to end up with the NASA Executives reviewing this Mod Factor, and since they are the ones who wanted the Rocker Panel addition to the items to be retained unmodified for a Production Vehicle in '12, it would not be beyond belief if they would say that it should be removed, and that any vehicle with these mods should be taking the Non-Production Mod Factor of -0.4 (120 lbs for a 3K vehicle). 7) I say let this one go now.... Quote Link to comment Share on other sites More sharing options...
Bnjmn Posted December 18, 2015 Share Posted December 18, 2015 Greg, this mod is permitted in GTS and you know that more than a few GTS competitors are looking into ST. This mod didn't seem to cause any consternation in the GTS format (particularly regarding point #5), why the different thought process for ST? I have also seen a bit of cut floors on GTS cars, why not grandfather them into the rules so these people at least stay with NASA instead of jumping ship altogether? Quote Link to comment Share on other sites More sharing options...
kbrew8991 Posted December 18, 2015 Share Posted December 18, 2015 #3 and #4 will be repeated by Greg over and over and over... take the -0.2 and make it work for you Quote Link to comment Share on other sites More sharing options...
hispanicpanic Posted December 23, 2015 Share Posted December 23, 2015 I just had a 6 point, detailed post, and it somehow got deleted when I was about to post. Here are the bullets: 1) This has nothing to do with Corvettes that I know of. 2) This is a benefit to those with the modifications already, because otherwise they take the -0.4 Non-Production Mod Factor Creating this mod factor for those that would otherwise take -.4 was pretty nice of the rule makers. I think it might be worthwhile revisiting the impetus for this. Why did those folks get special treatment? 3) The -0.2 is only 60 lbs for a 3K vehicle. Not the point, but helpful to consider. 60 lbs, especially when you control where it comes from is a lot. On a well setup car, 20 lbs of fuel can make a neutral car an under steering one. Or visa versa, depending on the car 4) If someone has these mods, and doesn't think there is a performance advantage worth 60 lbs, then re-route the exhaust back under the floor and under the rocker panel. I don't think anyone would go through the trouble and expense of this mod if they didn't feel it absolutely necessary (corvette vapor lock dudes) 5) If it is potential performance advantage for lowering the vehicle for direct handling effects of both lowering the center of gravity and for aero purposes (especially when additional aero mods are added), and there is no Mod Factor for it, then it basically becomes a required modification for everyone who wants to be competitive. NASA does not want this to become a "required" modification. You see, A7's are a required performance advantage. I can't remember the last time someone won TT without A7's. And if you take an aero hit, an underbody and huge custom splitter is absolutely necessary. You've got to build to the fullest extent of the rules, ride heights not withstanding. TT/ST rules are supposed to be "unlimited". I think this reasoning is a bit contrary to the purpose of the class. From personal experience in star mazda, i did not find aero to be significantly affected by ride height. Yeah, open vs closed wheel is different, But the physics isn't, and i don't think extreme lowering and cranking up spring rates would provide ANY benefit on texas track surfaces (barring COTA), and i'd venture to say it would make a car slower and less consistent. But i digress. Exhausts can be routed through subframes or between suspension arms. If the rule was created to prevent extreme lowering of vehicles, then there's serious loopholes in this rule that need serious reconsideration. 6) Too much discussion of this issue is likely to end up with the NASA Executives reviewing this Mod Factor, and since they are the ones who wanted the Rocker Panel addition to the items to be retained unmodified for a Production Vehicle in '12, it would not be beyond belief if they would say that it should be removed, and that any vehicle with these mods should be taking the Non-Production Mod Factor of -0.4 (120 lbs for a 3K vehicle). See #2 7) I say let this one go now.... Respectfully, It's not in my nature I hope i'm not coming off as on the offense here, its not my intention. But as i'm looking through and trying to understand the rules, i'm finding it a bit hard to agree with much of the reasoning. In the other post in this forum, i asked for a declaration of the ST/TT rule philosophy to better guide our feedback on future rules. In trying to understand the rules, it seems to go against what i have come to understand as the rule philosophy. So revisiting the philosophy and such should help shut some of us up Quote Link to comment Share on other sites More sharing options...
brkntrxn Posted December 24, 2015 Share Posted December 24, 2015 I think it would be awesome if several of you could go back and re-read my post. COBRA /= CORVETTE Let me read it slowly for you. I never said anything about a Corvette in my example. kkkkk ooohhhhhh bruh does not sound like kkkkk oorrrrrr vvvvv vvettt uh There, now go play nice with Greg. Quote Link to comment Share on other sites More sharing options...
mcdonaldsracing Posted December 24, 2015 Share Posted December 24, 2015 So Greg, back to what DJ was getting at with his original post.....would we have to take that penalty for the minor mods to our floor pans to get existing equipment to work? His is pedal related from a floor mount tilton setup, and mine is where I had to cut out a small section of the floor (right where it meets the firewall) just so my manifold would clear on the passenger side. Neither one of us are running side exhaust. Mine was simply to gain clearance with my swap so I could get a manifold on the motor. If I need to email you specifics then that's fine. I'm just at a standstill on my car right now with the gts mess and need to get back going on things soon. Thanks John Huebner Quote Link to comment Share on other sites More sharing options...
D_Eclipse9916 Posted December 24, 2015 Author Share Posted December 24, 2015 So Greg, back to what DJ was getting at with his original post.....would we have to take that penalty for the minor mods to our floor pans to get existing equipment to work? His is pedal related from a floor mount tilton setup, and mine is where I had to cut out a small section of the floor (right where it meets the firewall) just so my manifold would clear on the passenger side. Neither one of us are running side exhaust. Mine was simply to gain clearance with my swap so I could get a manifold on the motor. If I need to email you specifics then that's fine. I'm just at a standstill on my car right now with the gts mess and need to get back going on things soon. Thanks John Huebner John, I emailed Greg and he dictated what I needed to send him, he was very responsive. I have to get my car up in the air once I am done with another project and take the pictures he needs to prove it is not a performance advantage in any way. Even then, it is still up to him to make the determination. #warts and all. I still think side exhaust/flat bottom aero/lower for aero all falls under the aero provision and will propose it again for 2017 when the rules are being reviewed. It may only be 60lbs, but for those of us who are optimizing, it is 60lbs to give up to our competitors. However, at the fear of NASA Nationals getting involved like they did with GTS, I wont even push on it for fear of them ruining another class. Quote Link to comment Share on other sites More sharing options...
mcdonaldsracing Posted December 25, 2015 Share Posted December 25, 2015 Sounds good! Quote Link to comment Share on other sites More sharing options...
Jaymz Posted December 26, 2015 Share Posted December 26, 2015 From one of the cars that probably started the side exhaust mess in 2012. The reason we initially built the side exhaust on two of the fastest ST cars that were racing at the time. It made them sound really fing awesome. That was it. One thing we learned in the process was that the car were actually safer with the side exhaust. Safer huh?? Let me explain. We took measurements of CO in the cars with the side exhaust and with the exhaust routed out the rear of the car. The CO levels were dangerous in the rear vs a non issue out the side. This is the primary reason I don't race this car anymore. The downside of the side exhaust was the interior of the car was hotter than the rear. It didn't affect how low we could run the cars at all as the ride height was not affected either way. My car has gone faster with the exhaust in the stock location so it's not a performance gain at all. (in my car, others may vary) I decided that I would vote with my wallet on this one. I was spending about 5k per year on NASA entry fees. I would Race and TT at every event and do events in multiple regions. Could I be swayed to come back and race if things were different. Perhaps. Who knows. I do like seeing myself on TV every week though. The problem is that people keep getting pushed away with the current rules. If the rules were lightened up on more people would come race. It's not that hard to understand. Racers are spending a lot of hard earned money to come play. Watching the threads of late that there is a few GTS guys wanting to come play and can't. Ok. I guess they can come play but with a 50-60 lbs penalty. Who wants to be penalized for something that is not a performance advantage? The way to get people back is to go to a straight power to weight modifier. Get rid of the extra points you take for the bs. Try it for a couple years and see what happens to the entries. I bet the series starts to grow again. Quote Link to comment Share on other sites More sharing options...
sperkins Posted December 26, 2015 Share Posted December 26, 2015 One thing we learned in the process was that the car were actually safer with the side exhaust. Safer huh?? Let me explain. We took measurements of CO in the cars with the side exhaust and with the exhaust routed out the rear of the car. The CO levels were dangerous in the rear vs a non issue out the side. This is the primary reason I don't race this car anymore. The downside of the side exhaust was the interior of the car was hotter than the rear. I would love to hear more on this subject as it explains a lot of the problems I've had with the C5's that I've raced. Were you guys able to come up with any solutions? Quote Link to comment Share on other sites More sharing options...
Brent Posted December 26, 2015 Share Posted December 26, 2015 Great post James. I'm in a similar boat. I think we were all drawn to NASA due to the open rule set back then. Just power to weight with incremental jumps. That has changed a good bit over the last several years. While it isn't the SCCA, it's also not what NASA once was. I was told a few years back that the square tube that was used for my LS1 conversion in my RX7 put me into the non-production category even though it does not offer a performance gain. It's actually the opposite as it negatively impacts the suspension geometry and I had to correct bumpsteer. I could, however, hack the stock subframe up and not take the non-production hit. I'm not a structural engineer to say the impact, but I don't think it is safe. It's ok though, I haven't been nor am I going to be the squeaky wheel and you will rarely see me post here. I'll play elsewhere for the most part. The constant rule changes are humorous and is almost a metaphor for society. I wanted to be a NFL player when I grew up. Unfortunately, I was not given the build or the talent to do so. Not every car is a winner from the factory. If your car sucks, either keep it because you enjoy it and keep driving it mid pack... or get a car that is competitive. Everyone is not a winner. I did the same. I got tired of getting beat by corvette's with my rotary RX7 so I put an LS1 in it. If you want to prove your are a better driver, race a spec car. The other reality (as James eluded to earlier), is that NASA isn't the only 'open' rule show in town anymore. It certainly is one of the largest. I still love NASA... not NASA National... the Jim's at NASA-SE , the Chris' at NASA-MA, etc... I do acknowledge it's not easy to be a steward of the rules, especially since it is not most of these guys day job. I also understand we don't see the larger picture, but I would guess Napoleon's Corporals would say they don't understand the new rule changes. Quote Link to comment Share on other sites More sharing options...
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