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PostPosted: Wed Feb 22, 2012 10:47 am 
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Hi Folks,

This is an unofficial unsanctioned uninvited inquiry into how to get locosts into SCCA GT club road racing.

The SCCA GT category is mostly home or pro built tube chassis cars from Renault LeCars (GTLite) to Chevy Corvettes (GT1). GTLite is the small bore class with motors from 1200 to 1800ccs. Uptill recently these motors have been highly tuned screamers. The introduction of a single inlet restrictor (SIR) has tamed these beasts to where an SIR equipped motor can expect a long lifetime and be built with less exotic parts. We're also kicking around some new ideas like a highly spec'd junkyard motor and/or a lower prep level (limits on things like compression and cam lift). We have costs in mind, but we want to maintain super cool tube framed purpose built race cars as our core philosophy.

The locost chassis seems like a great fit for GTLite. Light weight tube frame cars with a passionate home builder tinkerer owner. SCCA already has specs for building a cage on a Lotus 7 or Caterham for the production category, so that's not much of a hurdle.

The GTL rules provides a very wide array of motors from almost every manufacturer from Alfa to Yugo. Please check out the GTCS sections for GTL in our rule book (the GCR) found here: http://www.scca.com/assets/2012GCR-updatedJanuary3.pdf

This rulebook is huge, but please dont judge us by this. We support lots of classes, cars, tracks, formats, etc all in that one book. Jump to page 302 for the GTCS (general rules), page 322 for the GTL rules, and page 374 for the car/motor specific spec lines.

Since "locost" is not a manufacturer we will have to find a way to fit you guys in. My thoughts (worth what you paid for them) are that you could pick any engine from the list. You would have to run that engine at the weight speced (lots of ballast). We would also have to set limits on things like track and wheelbase. Although there are details to the rules (like no carbon brakes, limits on aero, etc), that's pretty much the extent of the rules. I know the weights will require you guys to run some ballast (dont forget the cage you will want will add some weight too). Ballast is not all bad. Having the weight where you want it is a BIG advantage when you all have to weigh the same. In other words, if I run 20lbs of ballast and you run 200lbs, you have a big advantage over me (lower CG, lower polar moment, etc).

I know that the club (SCCA) has a less than perfect reputation (unfriendly folks in white shirts, etc). As both a racer and a steward (my white shirt is in the closet) I can tell you first hand that although we have had our issues in the past, we are conscience of those issues and have made giant improvements. Our races are a truly good time with parties, camaraderie, helpful car loving people, and very close racing (and beer afterward).

Here are some of my in car videos from Watkins Glen in 2011 showing the close but respectful racing you find in the small bore national run group (GT and production):
http://youtu.be/TJJwMaXeIVk
http://youtu.be/fnkCTg1YFPE

If you're interested, or just have some questions, feel free to contact me. My email is disquek@yahoo.com and my phone is 215 850 1517. Also, if any of you folks are in the North East, I'd be happy to put you on my crew list for a national race and show you firsthand what our races are like. If you're from elsewhere, let me know and I'll find a GTL guy to host you where in North America. I can also point you to more GTL video online. We also have a facebook group (because all the cool kids are on facebook!)

So what do you think? Are any of you folks interested?

Thank you!
Kyle Disque

PS: my Dad has a '62 series 2 super 7 and so I've always loved these cars. In fact, if this flies, I may build one!


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PostPosted: Wed Feb 22, 2012 1:13 pm 
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I think that is a very interesting and intreguing idea that certainly has some merit. Are you looking more to get current Locosts built to any number of different configurations legalized, or new Locosts built specifically to meet GT class rules? I think this will have some effect on how good of a fit it is with the class as well as how to best integrate it into the rules to some degree. While there are a couple of reasonably "common" Locost engines used in GTL, and I do understand the advantages of ballast, the 750lbs or so that could be required to meet weight on some of those specific engines/builds still seems like an awful lot to allow people to just bolt into one of these little frames as they please...Although it might be amusing to see a locost built off a single piece solid 1" thick steel plate floor pan, rather than the traditional tubes and sheet. And while I do see a big advantage on the body work (or lack there of) side of things for a Locost, I'm also curious how Locost body packages (aero) would be dealt with considering how many variations are out there as well as some of the liberties that can be taken within the GT rule set. Remember that at a similar power/weight spec to other cars using the same engine, the Locost is probably going to be at a fairly substantial aero disadvantage, and will not have as significant of a frontal area advantage over many of the GTL sized cars to make up for it either.

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PostPosted: Wed Feb 22, 2012 2:33 pm 
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I think you've hit the nail on the head. Weight and aero are going to be the challenges. But these are not entirely unsolvable. We have minis with giant flares in GTL. These are aero disasters and they work.

The weight thing might require some creativity in the rules. We couldn't let the locost run the same motor as .. say a toyota chassis at a lower weight. But it would be awful to make the locost carry many hundreds of lbs of ballast. The current GTL model targets around 1900lbs with about 170hp. So keep this in mind when thinking about what weights and motors would work in a locost (less of both).

How much does a locost weigh with a full cage? When I say full cage, I mean something like this:

Image

Factor in things like fire systems, 8 gallons of fuel, a dry sump, even things like wings (legal in GT), good seats, a big battery (it's common to run a total loss electrical system using a big battery as part of your ballast), GT allows a quick change diff (it might be tough to find one small enough for a locost).

There are other options besides the existing motor spec lines, like finding a bike motor that works and creating a new spec line for something like a locost with a 1.0l bike motor at a reasonable weight. I'd think that would be really cool. There are oiling challenges when you put a bike motor in a race car, but the DSR (D sports racer) guys have found solutions (trick pans).

Thanks for discussing this!

-Kyle


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PostPosted: Wed Feb 22, 2012 4:01 pm 
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Another idea:

I think that a miata donor is a common locost build.

Miatas also make up our most popular class (Spec Miata).

What about having a locost with a miata donor be written into the GTL ruleset? It would be a stock miata driveline, brake, suspension (uprights at least), etc, with racing slicks, and some other GT goodies.

Since the power levels would be lower than our current GTL numbers, the weight could be far less too.

These things would last forever being light weight and understressed.

-Kyle


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PostPosted: Wed Feb 22, 2012 4:11 pm 
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Quote:
Thanks for discussing this!


Thanks for posting here and being interested in us. This question does come up periodically.

Are your GT weights including the driver?

I have been drawing up a variant on a locost by using an SCCA spec roll cage and then building outwards from that. Since the roll cage is stronger then the locost frame, it seems to make sense. People who don't track their cars can use a more robust protection too. The frame is still only about 140 lbs.

The weight thing is a problem for us. It is more natural for us to be 1200 lbs. and 140-170 HP. Securing 600 lbs. of ballast seems like it raises safety issues.

It would be great to have a class we could run. We just don't fit in the normal shape envelope :)

Quote:
super cool tube framed purpose built race cars as our core philosophy.


That's where I am trying to go with what I am drawing up. I think removing a few hundred pounds more weight can give you a car that really ups the driver fun factor and your ideas on things like the SIR are very sensible. The lighter car will not eat it's brakes or tires so quickly, making it cheaper to run. These cars are very simple to work on and easily go on formula car style sawhorses.

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PostPosted: Wed Feb 22, 2012 5:43 pm 
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Well when the F993 concept fell trough I decided to concentrate on my Locost.
Life kinda got in a way with some major projects at work, which I can’t really complain in this economy.

Are we talking Regionally of or a National Level ?

Personally I feel that GTLite weights are a killer for our cars. Forget about Aero, If I cared about it that much I wouldn't be building a Locost., Just the weight doesn’t make any sense. It’s very simple to build a 1300LBS(without drivers) car with a full cage with a car engine. Subtract a 100lbs for a motorcycle car. the GCR states a weight of 180lbs for an EP Caterham with driver. But since this is the racing section of the forum and you’ve kindly reopen my interest lets discuss.

The SCCA does have a regional class were a Locost can compete, i.e. SP. So in reality we have no excuses not to race. Seriously, build it and they will come… If enough Locost show up in SP and some structure can be developed over time, then maybe a national class could be created. This would require a unified effort by quite a few number. A number greater than all of the completed locost currently in N.A.

I’m just concentrating on finishing my car so I can get it on the track. I know that I’ll be allowed to play in several region with my locost and I’m happy with that. Especially knowing that my teammate might join me down the road…

Cheers,
Fred


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PostPosted: Thu Feb 23, 2012 2:35 am 
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Where is the SP class described? I must have missed it in the hundred pages of GCR I just scanned thru...

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SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.


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PostPosted: Thu Feb 23, 2012 8:03 am 
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Hi Marcus :
section 9.1 C 2
2. In addition, organizers may include either or both of the
following Optional Regional Classes in their events defined in
3.1.5, 3.1.6 and 3.1.7.
a. Super Production Class (SP) (Optional Regional Class):
Cars which exceed the preparation limitations of the applicable
Production or GT Category Rules but which meet the
General Technical Specifications of Section 9 of the GCR
for GT category cars. This includes cars not listed in the
GT or Production specification pages, such as FIA homologated
production cars.

Kyle, I've been thinking and your right, using stock or near stock motors could even things out with a lower weight. I understand that the weight you are mentioning are with drivers. My bad on my earlier post... No formula is perfect the target lbs/HP in GTlight is 11.17... figuring that a stock Zetec puts out 130HP, we would end up with a weight with driver of 1450 lbs... That wouldn't be too bad. Too make this attractive to others we would need to figure out a list of engines and weight required with them. I've realised that very few want to build a locost with a spec drivetrain, this is the main reason why a Locost sery never took off here. In other parts of the world were they had that issue they resolve it with a target power to weight.

Your idea has potential, I'll shoot you off an email... Yup I'm taking the bait on this one and bitting this could be very cool...
the plan is finish the car test run in it 2012, race it in 2013, Marcus you bitting ?

Cheers,

Fred


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PostPosted: Thu Feb 23, 2012 12:17 pm 
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Hi Guys,

I'm slammed at work and have to post and dash.

Thanks for taking the time to consider this. It's very exciting to think of bringing a whole new chassis type into GTL. Please remember, that this is very very unofficial. At the end of the day, we maybe able to put together a rule proposal, but even then there is no guaranty it will fly with the top brass.

All weights would be with driver and taken when the car comes off the track (low on fuel).

Since the club has extensive experience with miatas via the spec miata class, a locost with a spec mitata drive line would be the easiest route from a rules writing perspective. Other drive lines are certainly possible, but would require highly detailed specifications to be written into the rules. The miata already has these specs.

Other sanctioning bodies will dyno your car at the track and class you by a HP/Weight formula. I mention this because I think it was being alluded to in an earlier post. The SCCA will not. We feel that car/engine prep should be a factor in the outcome and so the guy with the better legal motor should have an advantage. That's why we require such detailed specs.

The rules for locosts in GTL (in addition to the safety stuff) would have to describe things like track, wheelbase, weight, body details, drive line details, and you would have to follow other basic GT rules like no carbon brakes, no push/pull rods, etc.

To help clear up the SP class and how it relates to GTL. SP is a regional only class. There are no SP races at national events. Also, in SP you might be on track with a 3200lb BMW. Not a pretty picture in a wreck. GTL, because it's a national class, has races at both regional and national events.

You folks have a great community here! I've lurked on many of your build for a couple of years and always enjoyed your helpful and appropriately critical commentary. Keep it up!

Just so you guys can get a better understanding of what a typical GTL car look like under the skin, here is a great photo gallery of a Nissan Sentra GTL car from a couple of years ago. This is not my car. Current cars include some minor tweaks from this car with things like rear wings and front splitters.
http://brittbrown.smugmug.com/gallery/3742523#P-1-9

Thanks again,
Kyle


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PostPosted: Thu Feb 23, 2012 1:37 pm 
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One comment on using the SM drivetrain - good Miata drivetrain parts are already outrageously priced thanks to the typical spec racing games and do not make good Locost parts. Most builders using Miatas as donors are using trashed cars that are in no condition to run in SM. You would automatically price most people out by doing this. Plus there are only a handful of these cars in NA to begin with and even fewer running Miata engines (the 4AGE is probably the most popular).

I would not limit it to one particular drivetrain but rather a displacement limit or offer a list of acceptable engine choices that have similar power capabilities.

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PostPosted: Thu Feb 23, 2012 2:28 pm 
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Hi Andrew,

Good points. I know that SM has driven up the cost of a miata.

Just specifying a displacement would force us to assume that the motors were "full race prep". Meaning high compression, big cam, fully ported, etc. For example, a 1600 4v would have be assumed to be capable 250hp. This is what a fully built formula atlantic makes with a 1600 4age.

So to keep costs down we need to be very specific with how we describe the entire drive line. We'd have to get every specification for every stock part of the drive line. Meaning exact cam profiles, crankshaft weight/dimensions, flywheel weight/dimensions, piston weight/dimensions, rod weight/dimensions, block weight/dimensions, head, valve, yada yada. This is for every single part of the drive line. This is very hard to do for motors that are out of production because it's hard to get new OEM parts and it's hard to ask a manufacturer to get the specs for a motor that's been out of production for 15 years (heck - its hard to get specs for current motors). Just as an example most manufacturers will have had ump-teen different cam profiles through out the life of the motor even though there is only one part listed in the parts book. It's not enough to just write the rule that "it has to be stock". You have to very specifically define what "stock" is. Otherwise, when someone wants to check, there is no reference to check against. Check out the SM rules in the GCR to get an idea of the scale of what's needed. Remember that the reason for doing this is ultimate fairness. We want everyone to be on the same page as to what they can and cannot do.

The nice thing is that we already have all of this for the miata. We would have to develop this for any other combination. So as a proof of concept, the miata is the easiest to do.

Just to level set: Although this is going to be quite inexpensive by road racing terms, it will be by no means inexpensive. So if buying a $4k donor car is an issue for someone, that person might not be a fit for national racing. Not to push anyone away. I just want to be totally honest and upfront here. For example, slicks are about $800 a set and you will be lucky to get four or five weekends out of them (I get two). Brake pads are about $150 an axle and they should last 10-12 weekends. Entry fees for a national are from $250-$400 per weekend. You will need a trailer ($2k min) and a truck to pull it. Spare wheels and tires. Rain tires. And so on. It's cheap compared to other forms of racing, but it's not "cheap". There are ways to cut down these numbers (used tires, etc), but I think it's best to be as up front as I can be from the get go.

-Kyle


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PostPosted: Thu Feb 23, 2012 2:41 pm 
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I'm wondering about that SIR idea. Perhaps that's a suitable way to level the playing field? You want to encourage the use of Zetec or Duratech that don't require extensive modification. Being able to get 50 hours out of a motor instead of 10 is attractive I think. Especially if your talking about attracting new people.

Complying with the general requirements like no push/pull rods is fine. I would try to find an approach that yields an absolute minimum of rules and requirements though. Allowing some creativity is also attractive for our base, otherwise we wouldn't be building.

I can see requirements for production base parts for uprights, brakes, clutch/flywheel, transmission and diffs. Give or take, I suppose.

I would try to be generous on ranges for track or wheelbase. Not sure what to do about bodywork...

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SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.


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PostPosted: Thu Feb 23, 2012 5:26 pm 
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I forget the special term used in the racing world but why not specify a price (lets say $1000) for an engine and if a competitor wants to buy it from you, you have to sell it for that price or you cannot race any more? If someone is dumb enough to buy a $20k Duratec 260, smoke everyone for one weekend, then sell it for $1000 then so be it.

For something like a Se7en where everything is custom, I think you would be further ahead setting some dollar amount versus trying to police every single detail.

I like driving, I would like to get into some wheel to wheel action at some point, but I don't see the benefit into paying more for something (IE a "factory spec" Miata engine) when I can get the exact same or more for less money. That logic is pretty much what the Locost is all about. If it wasn't we'd all be dropping at least $35k for a new or $25k for a used lower trim level Caterham.

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PostPosted: Thu Feb 23, 2012 6:09 pm 
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Andrew,

The term you're looking for is "claimer". As in you can claim someones parts for $xxxx. The SCCA does not have any claimer rules currently, and making major philosophical changes for locost in GTL will really reduce the chances of it working. Personally, I like the idea of claimer rules because they're simple. But they are super hard to enforce. The details make things rough. Sealed motors work better, but you have to pay someone for the seal. That's more expensive than it might sound.

As a veteran of SM, I can fully appreciate what you're saying about the level of prep there. But at the end of the day, this is racing. The guy that rubs on his parts the most wins. It's the nature of the game. Most folks who have been racing a while learn to appreciate that fact rather than be put off by it.

"Pro motors" in SM (legal ones) just mean motors that have been rebuilt and blue printed to a very high degree. They sell outright for about $3-$5k. Which is a lot for a stock miata motor, but not a lot for a race car engine. You can do 90% of what makes a "pro motor" yourself (with your machinist) for far less. You will have to buy a set of cams ground to the limit of the factory specs, but the rest is stuff any competent machinist can do. The rules do a good job of describing what needs to be done, and the spec miata forums fill in the rest.

A good "pro motor" will make anywhere from 5 to 15 more hp than the average Mazda supplied crate motor. I've owned both and can confirm those numbers from first hand personal experience.

No real racing series will build rules around a tired motor. Like I said before, with the cost of everything else, the cost of a decent rebuild is not outrageous. Plus, if you've never had your motor apart, you don't know what the previous owner did in there. I've seen SM racers shocked when they pulled apart their junkyard motors and found go-fast parts.

Racing is hard on time and money. But it's a lot of fun.

-Kyle


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PostPosted: Thu Feb 23, 2012 8:26 pm 
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No fancy engine rules are required...Just a SIR and minimum race weight correlating to the Locost itself, rather than being attached to the specific engine as on all other GTL specifications. If the cars turn out to be either over or under competitive, the size of the SIR can always be adjusted accordingly. Ideally this would allow for any of a multitude of engines, including some options growing in popularity which are not specifically allowed under current GTL rules like the Duratec...Although realistically getting buy in from other competitors might still be challenging on this issue as well. If it would give competitors a warm and fuzzy feeling in accepting such a proposal, you could even still attach something like a 2.0L displacement limit on the engines too maybe.

In my opinion "claim" rules might be fine for entertainment racing like lemons/chump car to keep everybody honest about the $500 they spent, but are terrible in serious competitive racing involving multiple thousands of dollars and hundreds (if not thousands) of man hours...Espeically in relatively open rule creative construction cars where much of the value might not be in the price of the parts purchased, but rather the time spend designing/developing/building the parts and setup often by the individual racer.

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