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As a former B mod competitor, it amuses me to see the wings on the sports racers, I just got a look at the wings on Evan Brauchs car, it looks like an A mod wing to me. How's this supposed to keep the Formula cars and specifically the F Atlantics equal, when the wings on the F Atlantics are restricted plus the cars have to be heavier than the Sports racers.

 

I'd say start with equal wing restrictions for all cars in B Mod as a way to start the equalization process.

 

I wonder if anyone even cares that the Formula cars are going extinct??

 

Jesus Villarreal

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Jesus Villarreal
D mod Europa

Jesus,

The rules for BM have been clarified for 2008 where the rules should be easier to understand and the oddball weight schedule that favored some sports racers like CSR is fixed.

BM is now basically " equal weight for equal motor". 

No longer can a CSR run an Atlantic Toyota motor and only have to weigh 1075# vs. the FA car's min weight of  1180#.

Actually, the way the rule used to read , it made no distinction on the myriad CSR engine sizes buried in the GCR (Solo: CSR all at 1075#).

One could actually have run a Cosworth YBM 2L in a CSR at 1075# with driver up to 2008 in BM. 

 

 

Maybe some details below will help you understand the wings you see now on SR better.  

SR  run GCR aero with a Solo over-ride of 8 total square feet limit and FA run to exact FA aero rules. 

If Bauch's wing area is totaled up, the F+R should be at or under 8 square feet.

For reference:  AM has a 20 square foot wing area limit.

In Solo or road racing , FA can probably actually run a little more  than 8 square feet of wing since the FA GCR aero limit is based upon other dimensions such as width (43" max rear. 59" front) and allowable extension behind the rear axle centerline (39").

Since GCR FA aero rules limits the overall height of all aero devices to 35" vs. the SR height limit of 45", that lower FA wing height diminishes FA rear wing efficiency a little. 

One data point we have is that when Tommy Saunders jumps in John Garcia's BM (un-narrowed) Ralt 3L FA at a local Solo, those times are comparable to Tommy's own times in the DSR (which runs a low front wing).

Chuck Voboril

 

 

 

P38overhead:

One data point we have is that when Tommy Saunders jumps in John Garcia's BM (un-narrowed) Ralt 3L FA at a local Solo, those times are comparable to Tommy's own times in the DSR (which runs a low front wing).

Chuck Voboril

That's funny. John is on the D-Mod mailing list claiming that Tommy's Dragon runs 3-4 seconds faster than his Ralt with a Nationals level driver in it. I didn't know Tommy had times in both cars.

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Aut tace aut loquere meliora silentio.

 Let me take a guess: The topic was probably "motorcycle engines"?

Tommy has driven both cars at one event and I suppose that John may have let other people drive his Ralt as well. 

I can't add anything more outside of what Tommy told us.

John should have his new FA car finished soon. I hear it isn't much bigger than Tommy's DSR.

Should be a neat car.

BM can use all the new cars it can get.

Chuck

OK, let me start by saying I haven't run B mod for over 10 years. It looks like the Formula cars are in decline, only reason for that would be that people are feeling that they are no longer competitive. The main reason I left B mod is because I had no one to run against in my region, and the sites being used locally are very bumpy. I still have the car, it is just sitting there gathering dust.

If the SR'ers are getting tunnels and their wings are wider and higher in cleaner air, then they have a distinct advantage to go with the narrower track and lighter min. wieghts, however as Chuck points out, the weights are being adjusted for '08.

Like Chuck said, B Mod needs more cars, and that is the reason for my posting this thread, I wanted to see what other peoples opinions are on the subject.

 

Jesus

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Jesus Villarreal
D mod Europa

Jesus,

Size and aero effects are difficult to evaluate for sure in BM.

One  can't say DSR are small and FA open-wheeled are big either now-since both types have large and small examples.

The current high downforce road race SRs are rather big-the purpose built ones are about 65-70" wide with WB out to around 100". 

Then there are open wheel cars converted for Solo that are pretty small like that almost 3L SuperVee that Vern Lyle had that had an 80" WB.

 

Size?

The cornering force available does go down as the car gets narrower. But you may go faster in a slalom and stay out of the sand more easily.  But, if one has a greater increase in cornering force from more tire or whatever, one can actually be faster in a slalom with a wider car than a narrow car with narrower tires.  2006 saw the fastest Corvette faster thru slalom than the fastest Elan in ASP. GT3 Porsche was about the same as the quickest Elan 

Aero?

Aero also gets worse as the car gets narrower and shorter. The rear wings of open-wheeled cars are blocked by the rear tires if one makes the car too narrow. A similar problem exists for SR since the body width sets the rear wing max width and narrowing the body diminishes the clean air on each side of the roll hoop to the rear wing. Both SR and openwheeled cars lose underbody downforce if the underbody area is reduced. Diffusers get narrower and less effective as both car types get narrower.

Now in Solo- what's an optimum vehicle size for BM?

Probably not so wide you that you lose time in the slaloms that you cannot make up in all the other corners.  FF1600 in CM have generally had a clear advantage over F500 in that regard in just about every course one can imagine.

2007 Nationals had fairly good cornering speeds and I think that Greg Scharnberg was something like 7th this year in his BM Ralt. You might ask Greg, but I don't think that he did anything to his car to speak of-just drove more events this year perhaps? 

 

If one looks at Street Prepared and Stock classes where the small cars aren't always the fast ones ones-there may be something to learn there.

Not just mod class cars are having trouble with the new surface. The Elan is doing poorly in ASP against the Corvettes now. Ted Lewis (a local for me) did a terrific amount of work on his car for this last Nat and if you ignore his pylons would have been about mid pack. He may actually have done better at Forbes Field before he did all this work.

My 2 Centavos is that a FA like yours can be competitive now, but it will take work-perhaps different work than you would imagine.

Beyond suspension alignment for the surface, modern shocks, new wings-or at least some hacking on the existing ones, different tires,  limited slip adjusted for low grip asphalt, you also might try looking at least narrowing up the rear of the car.  Many in the mod ranks are also going to narrower tires all around (at same overall car width in the front).

If I remember correctly, a Ralt in original SuperVee trim with 6's and 8"s was only about 62" wide-about like Brauch's DSR perhaps.

Hmm, ,just looked up the Cheetah SR-1 DSR and factory spec has it at 64" wide and 90" WB. Thats about 6" to 7" wider than a LeGrand DSR.  I reckon that you may be able to get close to that and also have wider rims.  Maybe 65- 66 inches wide like one of the the narrowest FF1600's in CM,  but with 9's F and 11's or 12's R for rims.

Chuck

Chuck, jesus , this is john Garcia,

Tommy jumps in my car and only goes 1 second faster than i do in my own car that leaves 3 seconds on the table  with tommy in his car.

If tommy said to you he can do the same times as his DSR in my ralt  with him driving  he is lying through his teeth and i am willing to put 1000 buks up to prove it.

I fully agree with Jesus  there is a huge problem  right now in Bmod . The weight thing you are talking about screws the atlantics and other non DSR cars again .  It makes it harder for any other car to beat a DSR or 1000 cc bike motored anything, because weight was added to them not the DSR's / FS 1000

With a mc powered formula special built small one can get to 1020 pounds the srs are at   If one builds a CGR LEGAL COMPETATIVE  ROAD RACE ATLANTIC  they get no weight breaks .

Unless  the 2008 weights raise the dsr weights to 1200 a  GCR atlantic cannot even touch the legrand.

 

JOHN GARCIA  

 

Oh and by the way my car is a  SUPER VEE car RT5 with a   13b  motor  not a 3 liter motor .

I guess it helps for chuck to be building a 2 stroke sports racer and wanting to keep the small car weight advantage aver an atlantic.

Lets get real here  Jesus Is completely correct in virtually every point he made . The atlantics are getting screwed in the bmod rules set.

 

 

 

 

I think someone has some badly filtered second hand information if they insist that Tommy says he can drive John's Ralt as fast as his own Dragon. At minimum somebody is trying to apply a single isolated case as a blanket statement. That would be irresponsible and doesn't wash.

 I've been co-driving John Garcia's Ralt for the majority of this season. I have a tremendous amount of respect for Tommy's abilities as I have witnessed them first hand at our local events for years. Tommy is very fast and knows how to put a car together but I can assure everyone that overall he would never be able to run identical times in the Ralt unless he were sandbagging in the Dragon ;) If the course is a more wide and open roadcourse type that favors power the Ralt is competitive. Anything resembling a true autox course (especially one with narrower lines) and the smaller and lighter DSR type cars have a generous advantage IMO. I've driven other DSR type cars in BM and though they have less acceleration ability there was never any doubt which car would be my first choice. The smaller and lighter DSR cars make much easier work of the course, no matter how narrow you were to make the track of the Ralt or how much money you were willing to spend to get weight out of it. I don't have a dog in this hunt as I don't own any of these cars but anyone building a truly competitive car who would decide to bring a converted Formula type car into B-Mod over a DSR type would cause me to scratch my head.

I did drive times similarly to Tommy once. The course was wide and fast with few transitions and Tommy had left his wings in the trailer ;)

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Scuderia Povero

Chuck your assement of a modified ralt is completely wrong ( sounds like it came from the ramblings of Tommys mouth,and remember his responce to a protest is  "who cares if it is honest or not  as long as you can convince a protest comitee that is all that counts")  it sure sounds great to a non educated  and non engineer  but is completely incorrect to justify the lower weight  of a car you are building ,

First read Ron Tarnacs book on formula car design ,  cornering force  does not necessarly get reduced as the car gets narrower  especially  with non fouled wings like in a Dsr car. in Fact Ron Tarnac who designed all the ralts brabhams, marches  says exactly the opposite of what you do , he indicates that with improved wings  that he narrows the car to reduce  frontal area  and improve suspension responce with no reduction in cornering force , formula fords and  non winged cars benefit from wider track but not  cars with aero This matches exactly with my own CFD programs  .   He also indicates that  while longer wheel base is more stable that by controling anti dive and anti squat in a shorter wheel base car with aero  that a car can be produced with faster steering responce and transition , he purposely says he designs long cars for formula  type courses so they are slower and more gradual in responce to allow the driver to catch up with the car. Next high speed aero is better with a longer  car ,at the expense of polar moment and chassis frequency ,  lastly    drag is reduced by placing the tires and wheels way away from the body  that is why formula fords are built that way, no aero,  limited power  . Formula atlantics and higher powered formula cars are not  power limited so all have a narrower rear track  compared to the ratio of formula fords,  DSR and other sports racers  have even more non fouled down force  , so can be even narrower and still generate the same or more cornering force  than an atlantic .   Your  completely incorrect assesment even of CM to continue a clear design performance advantage with DSR type cars powered by power plants that have the same power as a water cooled formula Super  VEE is  just plain criminal,   especially when as I understand it and as Tommy says it,  you are building a DSR type car and sit on the Mac just like tommy.

Be honest for a change  add weight to DSR cars to get them up to 1200 pounds so they are properly  handicapped for their  engineered advantage  that exists with the new  available power plants,

  

John Garcia,  BsME,  BsEE, MsME,MsEE , Phd, Jd, PE

 

Hi John,

 I figured you'ld chime in sooner or later, it's pretty obvious to me that the FA's are in decline, and it's not because they are competitive. With HPT's surface and obviously narrow lines because of the lot size, the narrow cars have a distinct advantage.  Horsepower means next to nothing at HPT, so the tiny motors in the SR's are actually another advantage for them.

 

Sorry Chuck, but your explanations are not making sense to me, I see  a definite problem in B mod. Rules and weight adjustments are needed to make things equal, even if we go back to Forbes Field. 

Just My humble opinion 

Jesus

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Jesus Villarreal
D mod Europa

Before anyone considers porking up the DSR weights I suggest someone takes into consideration the effects of a 1200 pound car on a liter bike engine clutch that was designed for a 400-500 pound motorcycle with with only a fraction of the tire contact patch. I'm really not interested in trashing my clutch every other event.

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Joe Gonzalez
1979 Legrand DSR- B Mod
Gilbertsville, NY

There are currently clutch  upgrades that  are in the aftermarket that have been used for 1200 pound   lotus 7 clone type cars . They include additional thinner clutches and additionl floaters with marginaly heavier springs , billet baskets etc . These are available for most 1 liter and 600 cc bikes as well as the Busa motor . They have been available for quite a few years due to the drag bike market ./  They are just about 100 dollars cheaper than the clutch system  in my ralt. Below is just a quick search on motorcycle / Yahama R1 racing clutches.  Quite frankley the clutch system is designed  based on torque capacity  and thermal load. With either a mc cartridge transmission or a dog box  in a automotive system  most clutches can handel twice the engine torque easily,  Only launch is the issue  , if you do not have to do a drag race start then you are no different than us autoderived  cars,

I  replace clutch disks, pressure rings and turn a fly wheel  every year.  Why should you be any different   8 >) ?

http://www.muzzys.com/ZX10/ZX10_Lockup/index.html

http://secure.mycart.net/catalogs/index.asp?category=19511&count=1

http://www.kneedraggers.com/details/Graves_Clutch_Plates_Yamaha_R1--613840.html

http://secure.mycart.net/catalogs/catalog.asp?prodid=3372654&showprevnext=1

http://www.motorcycletoystore.com/sport/shop.php/engine/y-e-c-racing-clutch-spring-set-yamaha-r6-2006-2008-/p_2380.html

jg

There are no weight related proposals on the table at this time, this is only a discussion right now. Unless the SEB and related rules makers want to see the Formula cars survive, then there probably won't be any weight adjustments. For the sake of B Mod the class, I hope either there are ways to get the Formula car owners back in the fray, or a lot of people build Sports Racers and support the class. I actually considered putting a SR body on my Ralt back in '98, but decided to go in another direction, I saw this movement to SR's in B Mod 9 years ago, when I parked my Ralt in the rafters of my garage.

 

Jesus

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Jesus Villarreal
D mod Europa

I bought this stock bike engined vehicle precisely because I had no interest in changing clutch discs every year or rebuilding Hewlands :) I was just throwing the clutch issue out as something to consider before a ruling is made. An old Legrand was never designed to carry 1200 pounds so there is quite a bit more stuff that would be impacted by raising the weight to almost twice it's original weight.

Sure all these parts can changed out or beefed up, but why penalize the fast cars? Why not make the slower ones faster with weight breaks or aero aids? I'm all for a bigger B-Mod class, though here in the north east most of us are chasing Fish's Ralt most of the time, so you're not getting too much sympathy from me on the shortcomings of those cars ;)

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Joe Gonzalez
1979 Legrand DSR- B Mod
Gilbertsville, NY

Gonzo_BMod:

  Why not make the slower ones faster with weight breaks or aero aids?

Do the open wheeled B Mod cars carry alot of ballast that would be easy to jettison?  Or would losing weight be an expensive exercise?

 

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Jim Garry

My car, And at least 5 of 12 I know cannot make minimum weight in a ralt rt car  even if we were to remove all the body work wings and run magnesium wheels.Or are at only 20 pounds above 1285 # with a 1600 engine.  Complete  I am at 1428 with no balast and Magnesium wheels right now , i am real small framed person right at 5'4" ,.

I Actualy know the legrands very well I have repaired and resurected many ,  in addition i know GONzales particular car almost intimately  since it was originally in florida then came to texas a few years ago before he bought it. , and the legrand can carry 1200 pounds (remember driver is included ) with no problem at all . At speed on a road course the body and wings make enough down force at 100 mph to push the effective weight of the legrand well over 1350 pounds so  the construction is stought enought to survive a wall crash, down force and a season of harsh road racing  from an engineering stand point  not much needed  except balast .The suspension and damper should already have been set up for that much static and dynamic weight  on the legrand .  The ralt rt car would require the tub to be swiss cheese cut up to get down to weight ,RT 5 cars already have the lightest transmission capable of  being put in the car , I have a rocker arm suspension  car which again is lighter than a pusrod car .  Cutting up a Ralt is as bad as cutting up an orginal  precious painting   completely devalues the car makes the car unsutible for road racing and cannot be returned to original as well  destroys  one of only 127 ever built  real historical race cars . So modifications on Ralt tubs is not an option for any one that has one and understands  how significant Ralt cars are. That is one reason I bet Jesus has not sold his. What one may not know from a historical perspective is that Ralt had to widen the front of the RT cars to remove a design flaw push  in the entire RT 2 through RH 6 cars  , The suggestion by  a very un informed ( or maybe infromed but  evil) source that narrowing the  RT car can be done and still have it handle competatively  is very much Folly as well as another subversion from some SR guys to keep the major advantage . As an experienced engineer , fabricator, and machinist (I paid way way through school as a machinist) There is a purposely contrived advantage being given to DSR cars, too bad SCCA does not have a rule against having class competitors on the advisory comitees they run in .

It is not in anybodies interests to have the atlantics ; right now the ralts ; not participate, If the ralt drivers were to have boycotted nationals for the last 2 years , It would have signed an end to bmod as a class.

I got a buddy of mine to co drive that never had been in my car and played nurse maid to him at my expense , (driving and economic) so that we could make numbers this year. If the last 4 rt drivers in mens and the 1 in womens dropped out Bmod would not have the cars to make class numbers .  The attitude from the legrand owners seems to be pretty self involved  and intended to maintain a undeserved advantage.  Maybe  all of us Atlantic guys should boycott nats and let the legrands and MC cars end up with no where to run except amod as that would show that they have no class ,

So  as Jesus has said , The class will die out  and legrands will go where they should be anyway AMOD.  8>)

John Garcia

BsEE,MsEE,BsME,MsME, PhD, Jd, PE

 

 

 

John,

 

Sorry but no matter how many engineering degrees are tacked on behind one's name I will never buy the argument that downforce and static weight will have the same effect of a cars's suspension, chassis, brakes, or drivetrain parts. I have to put over 30 pounds in my car now now just to get my son to make the 1020# weight min. in this car. I do not see how one can safely and effectively add 200 pounds to a car this size without significant expense and re engineering. As for cutting up a car, this one has already been cut up to make the 80" WB minimum. If you want to keep it stock for value etc, go vintage racing. The name of the class is MODIFIED is it not?

 
Threatening a boycott is just plain ridiculous seeing as the purported purpose here is to "help the class", don't you think the DSR's could boycott the same events if it came to it? Then where will B Mod be? That's not the answer.

I am very new to this class and still sorting the car out to get it to Nationals in '08. The NT events and Divisionals that I have been to with it in the Northeast have all been won by a Ralt over DSR's (a full aero DSR with a former national champ driving who is the original designer of Saunder's current car).  

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Joe Gonzalez
1979 Legrand DSR- B Mod
Gilbertsville, NY

Jim G:

Gonzo_BMod:

  Why not make the slower ones faster with weight breaks or aero aids?

Do the open wheeled B Mod cars carry alot of ballast that would be easy to jettison?  Or would losing weight be an expensive exercise?

 In ''94 My car weighed 1240 without driver, I spent 3k in new body work to save 60Lbs, then the car was at 1180+ me at 210lbs, I was over minimum by 110lbs. That was without a fire extinguisher and anything that is not needed for Solo2. The DSR's are at 1080 with driver and they have to add ballast to get there, so that and more efficient wings and aero make them a better choice. 

 

Jesus

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Jesus Villarreal
D mod Europa