LocostUSA.com

Learning how to build Lotus Seven replicas...together!
It is currently Wed Jul 30, 2014 5:14 pm

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 24 posts ]  Go to page Previous  1, 2
Author Message
PostPosted: Thu Feb 23, 2012 10:40 pm 
Offline
User avatar

Joined: Sun Oct 15, 2006 11:15 am
Posts: 870
In my honest opinion I would try to have as much GTlite rules intact. The goal is to join the class, not make too many exeption that the current establishment will simply not bother with us.

Engine wise, well I might not make much friends here but I would not stray too far from the list of accepted engines in GTlite. If building a car with an engine from the current list is a deterent, well I would think that the class might not be for you. The engine is only one component in the car, with all the other possibilities offered by the class, there a lot of places to be creative. The lower weights to make the class attractive to a Locost racer brings down the power of the engine a lot. I mean were looking at 130-140 HP for a 1450-1500lbs car with driver there no point into chocking a stock engine just to bring it down... I look at the 4AGE or the mazda 4 cylinder 16valve engines and they require a 23mm restrictor for an 1900lbs car, how small would the restrictor need to be for a 1450 lbs car ? Imagine an engine with 20% more HP are we going to need FSAE type restrictors at 10mm ?

The reality is that this class is for pure racecars not street drive or street base locost so might as well start from scratch or close to it. The rules dictate a max of 60 inch track. A book Chassis has a 90 inch wheelbase, upright should remain free as in the current rules, same with tranny and diffs, the current allowances should remain for the locost.

cheers,

Fred


Top
 Profile  
 
PostPosted: Fri Feb 24, 2012 2:31 pm 
Offline

Joined: Mon Oct 19, 2009 9:36 pm
Posts: 1478
Location: meadview arizona
not to rain on anyones parade but, and thats a big but.

what do you think the word lowcost means, $5000.00 for a motor, i paid $300.00 for my duratec and it came with a whole vehicl attached!

the cost of a race entry is a weeks wages for me if i'm lucky.

i built my car at home with no specialized equipment, just hand tools a cutoff saw and a welder which is 30 years old.

because of where i live, just to buy some dom tube i would have to go about 600 miles round trip in a truck, just this cost alone is prohibitive with gas at $5.00 a gallon.

i have got about $6000.00 in the whole car and i can't afford tires yet.

what you need is a class for locosts, built to a spec. as they do in europe, a basic chassis, a specific roll cage and an engine that is within the reach of almost anyone, and yes a buy in on the engine, and also a spec for the donor or donors with regard to brakes, steering, transmission and rear end and dare i say it a spec. tire, no slicks.

this would be a locost racer, believe me i have worked in the club racing scene as a professional and nothing is cheep, machineist ha! the best i can find is a head reface and that destroyed the head as he didn't level it before he cut it, no machining of anything period, especially flywheels.

different donors could be subject to different weight breaks if the chassis were all equal,

most locost builders are not interested in an engine that lasts 10 hours, we are interested in an engine that may be 10 years old and will last another 10 years or at least can be replaced for a couple of hundred bucks.

i understand that some here are building cars that could be discribed as exotic but that is their choice, if your intention is to go racing, then build a car to fit the class, and a real cheap basic spec. class would be supported.

if someone wants to build a car with an l.s. motor they can but it wouldn't fit in the chassis, and if they did squeeze it in the weight penalty would be too high to be practical.

you are trying to make locosts fit your class when most locost are built to a personnal taste so make your class fit locosts

people here are talented people but we are not made of money, thats why they are called LOCOSTS, Ron Chapman would be rolling in his grave.

_________________
drag racers lament

oh to go down to the strip again where the blacktop meets the sky
all i ask is a small block and some fuel to make her fly
with slicks a smokin pushrods pokin next round i'll get a bye

she's up on song the shift was strong in the finals to boot
it's back to the pits and take it to bits and don't forget the shute
the final round was good and sound so come on give me the loot


Top
 Profile  
 
PostPosted: Fri Feb 24, 2012 6:39 pm 
Offline
User avatar

Joined: Sun Oct 15, 2006 11:15 am
Posts: 870
Hi John,

I understand what your saying and Kyle is not proposing an entry level class but getting the Locost accepted at National Caliber level.
Unfortunetly unlike the UK we do not have a small light weight cheap donor... The closest things to a single donor we have is the Miata...
BTW the average budget for a season in the UK Locost serie is 3000-5000£ that's close 5000 to 8000$... You're right racing aint cheap. Even worst when you have a moment...

I've done enought Solo 2 and Solo 1 as a participant to know what I'm getting myself into. I've been a crewmember for the 4 years in RR so like you pointed out I know not to trust anyone doing work on my car except myself. I'm sorry but no engine will last 10 years in a race situation, thats simply not possible. a couple of season maybe, but not 10 years... and don't forget just traveling, lodging is a a big part of a race budget...Gas is a killer .


Top
 Profile  
 
PostPosted: Fri Feb 24, 2012 7:45 pm 
Offline
User avatar

Joined: Mon Apr 12, 2010 5:40 pm
Posts: 1819
Location: san francisco bay area
What if you created a something similiar to the old Swiss taxable horsepower formula?
Attachment:
ae8d74220a7ab7a50bc0dd3e37664fbe.png
ae8d74220a7ab7a50bc0dd3e37664fbe.png [ 969 Bytes | Viewed 660 times ]

i is the number of cylinders, d is the diameter (or bore) of the cylinder in cm, S is the piston stroke in cm[3]

You'd have to create a variable for carb(s) sizing which would allow you to make a multi carb setup and a single carb more comparable competitively but. ..
Verifying compliance to some degree would be fairly easy with a TDC checker, a dial indicator and away to verify restrictor plate sizing but would take time I doubt anyone would want to put in.
Of course then you have to have some sort of way to challenge an engine and a way to calculate a penalty for not meeting spec and a way to discourage overuse of the rule.
Sure sure I used to run beehive springs on my Skylark so I didn't float the valves (claimer class circle track) but that's not enough imhop to make much of a difference on today's much more tightly wound engines.
Heck a stock C code 289 was rated (depending on who you ask) from 175-200 hp and today that's right in there for 122 CID :shock: What a difference a decade or four makes.......

On that note. .. http://www.youtube.com/watch?v=FK3TIYG9mqM

_________________
"There are times when a broken tool is better than a sound one, or a twisted personality more useful than a whole one.
For instance, a whole beer bottle isn't half the weapon that half a beer bottle is ..." Randall Garrett


Top
 Profile  
 
PostPosted: Sun Feb 26, 2012 10:35 pm 
Offline

Joined: Wed Jun 02, 2010 8:55 am
Posts: 10
John,

I fully understand your frustration.

However, I think Mr Chapman would be thrilled to know that he has a part in reducing the cost of entry into GT racing by a factor of four (at least).

Real racing is not cheap. I make no apologies for that. It is what it is. There are series specifically designed for sub $500 cars.

A miata donor locost would a blast to drive and it would be super cheap (relative to anything that can turn a similar lap time). In my opinion, that's the mark of a great design.

-Kyle


Top
 Profile  
 
PostPosted: Mon Feb 27, 2012 2:38 am 
Offline
The voice of reason
User avatar

Joined: Thu Jan 10, 2008 4:47 pm
Posts: 5516
Location: Massachusetts
I don't understand the lean to the Miata donor. What difference does it make which spindles you use? What's the advantage of a Miata diff compared to a Subaru? Leave as much of this open as you can and let the class members decide. Some day maybe they all use one part, maybe they don't. Engines out of things like Ford Focus or Ranger are easier to get, just pick a size for the SIR and see where people go.

_________________
Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.


Top
 Profile  
 
PostPosted: Mon Feb 27, 2012 7:04 am 
Offline
User avatar

Joined: Fri Nov 07, 2008 4:48 am
Posts: 1083
Location: snow city - it's wet!
horizenjob wrote:
I don't understand the lean to the Miata donor. What difference does it make which spindles you use? What's the advantage of a Miata diff compared to a Subaru? Leave as much of this open as you can and let the class members decide. Some day maybe they all use one part, maybe they don't. Engines out of things like Ford Focus or Ranger are easier to get, just pick a size for the SIR and see where people go.

This is the right line of thinking. Spec the SIR, minimum weight with driver (and make it easy to hit with a typical build), max hp, max torque, eliminate aero, specify the wheelbase and track, probably also consider a spec tire or tire size.

That would allow builders to explore in the early years while the formula for an optimal build is worked out. Over time it is inevitable that a standard formula will evolve, and that those who need to win will be willing to outspend everyone else - $40,000 to build a nationally competitive spec Miata, anyone? But a relaxed spec leaves the series open to disruptive change and evolution. You can't control spending, it just moves around the limitations; letting people re-invent the series will at least keep it from stagnating.

My thinking on a spec tire is mixed. Limiting the tire will enforce closer racing within a given build formula, but could also limit the ability to create innovative new builds. Unlimited tires will probably also tend to drive costs up as people develop track specific tire and suspension kits.

_________________
.. in the world


Top
 Profile  
 
PostPosted: Tue Feb 28, 2012 6:14 pm 
Offline

Joined: Mon Oct 19, 2009 9:36 pm
Posts: 1478
Location: meadview arizona
if you look at what i'm saying, i do not think it is a bad idea, on the contrary, it is fun to race until you get to the point that its harder to go to a race meeting than go to work,

believe me i know.

perhaps if you limit the tire and start from there, after all you can only do so much with a given tire size and compound.

as i said if you have different weight breaks for different donors,

that said, my car weighs a ton, well not literally, it uses merkur scorpio hubs and spindles and merkur rear axle, the power is 2.3 duratec and a ranger 5 speed, its a big car as locosts go but i built it for the street, not for racing.

if i were to build the ultimate racer locost, i would build as close to the Ron Chapman car as i could.

you may ask how,

well i would start with the motor, a 1600 cross flow from a 1980 ford fiesta, then a pinto 4 speed, that will bolt right up to the motor, 4" set back allowed, it saves making a remote for the shifter.

front spindles and brakes would be pinto, the rear end would have to be ford capri as would the rack and pinion, not the fox bodied, but the v6. steering column would be from a ford escort, master cylinder would be pinto

the frame would be by the Chapman book, with the previso that the front a arms would have to suit the width of the rear axle.

bodywork as the book, ally floor pans allowed, no carbon fibre.

the only variables would be shocks and springs, 1/2' hiem joints would be fine as i don't think the triumph bushes are man enough for the job, the pivot bolts are too small and they are difficult to get.

wow! why did i build the car i did when i could have had that?

state of tune of the motor, maximum one carb, down draft, probably a webber twin choke, stock 1600 factory cam as in the fiesta, tubular exhaust of any type, ignition open, fuel tank volume open.

wheels 13" x 6" ally or steel no slicks.

full cage.

yes this is all available at my local wrecking yard today,

tune the exhaust and spark curve for peak performance, tune the shocks, springs and tire pressures for the circuit.

_________________
drag racers lament

oh to go down to the strip again where the blacktop meets the sky
all i ask is a small block and some fuel to make her fly
with slicks a smokin pushrods pokin next round i'll get a bye

she's up on song the shift was strong in the finals to boot
it's back to the pits and take it to bits and don't forget the shute
the final round was good and sound so come on give me the loot


Top
 Profile  
 
PostPosted: Fri Mar 16, 2012 1:50 pm 
Offline

Joined: Wed Jun 02, 2010 8:55 am
Posts: 10
Hi Guys,

Sorry for not posting for a while. I'm not a regular here.

The reason for the miata donor is the SCCA's deep understanding of the miata. The Spec Miata class is super popular and highly contentious. The SCCA has developed a very specific set of rules for the Spec Miata drive line/brakes/suspension/etc. So we could simply apply those rules to a locost/miata.

If we were to open things up to other donors/pieces we would have to get a similar understanding of those motors/trans/diffs/brakes/etc. This simply isn't viable for the number of cars the locost/GTL could field. You'd be amazed at the variation of what might seem like a simple one makde model driveline. Look at the 4age as a wild example. Design revisions in driveline and varying suppliers can create the opportunity to make an engine (or any other piece) that's "more equal" by mixing all the best pieces. The Spec Miata rules have already addressed this and it's taken the better part of a decade to get it right.

If we allow open rules (like the current GTL rules) for a locost in GTL, to keep the playing field level, the locost would either have to weigh around 1900 lbs and use an SIR in the 23-25mm range (thus being like the current generation of GTL cars), or it would have to use a far smaller SIR (guessing 18mm-ish) to make the power to weight ratio comparable with the current generation of GTL cars. Either option be VERY expensive for the locost builder and thus mitigate the reason for doing this in the first place. Like $10k-$20k for a motor. Current GTL motors are fully custom 15:1ish full race motors. Steel cranks, custom rods, custom pistons, Ti valves, custom cams, dry sump, extensive head work, etc. Big big money.

The Spec Miata drive line (about 120hp at the wheels) in a 1400lb locost would be bullet proof, cheap, and great fun. They're already bullet proof in a 2300lb Spec Miata. Removing 900lbs would make them last forever.

I know that the locost community is based on an open and creative approach to car building. And that's awesome.

However, open and racing equals one thing. Expensive. The goal of this exercise would be to provide opportunity to be creative (locost) while still keeping the costs under control (miata).

I know that for most of you who already have projects well underway or completed, this is a let down. But for some folks that can put together a miata powered locost, this could be a great opportunity to race competitively in a top tier SCCA national class for a fraction of the typical cost. And at the end of the day, isn't that what the locost idea is all about?

I've been approached privately by a few of you guys that are interested. My real goal here is to see what the interest level is like. So if this is something you might consider, please contact me at disquek@yahoo.com

Also, look at some of the various locost series being offered in other countries. They are all similar in that they allow only one drive line and spec things like weight, track, wheelbase, etc.

Thank you again for considering this and helping to shape it.

-Kyle


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 24 posts ]  Go to page Previous  1, 2

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
POWERED_BY