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Old 11-27-07, 11:41 AM   #381 (permalink)
Grant B
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Re: RCR's Next car should be.....

Quote:
Originally Posted by slimneill View Post
Fran, How about an LMP type open cockpit type car or a SLC roadster?
A SLC-R do you have that variation in the works?
I'd love a simple, light, mid-transverse engined car with modern aero. Like the SL-R with a LMP body put over it. Open top, no doors (and yeah, I'd race it in the rain).

I love the look of the SL-C... But I go through 4 sets of tires a year, give or take, and those 345/30/18 rears are expensive (and no, I cannot resist using anything smaller). I much prefer a smaller, lighter and simpler car with a transverse engine.

However I have no idea what sort of work and cost this would entail. There is also the issue of how the police would react, as the raciest things we see around here are Cobra replicas. I can't even imagine what they do when they see an Ariel Atom (other than tase first, ask questions later).

Ah well... Maybe I should just pick up some CFD software and learn how to work carbon fiber. How hard can it be?

Grant "I wish I could pick up an Audi R10 from the dealership" B.
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Old 11-27-07, 07:46 PM   #382 (permalink)
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Re: RCR's Next car should be.....

SLC-R...the guys at the shop and I have talked about it quite a lot.....its not quite as easy as chopping the roof off.....unfortunately....

We have a very nice T70 spider too, though....wink wink.
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Old 11-28-07, 06:16 PM   #383 (permalink)
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Re: RCR's Next car should be.....

Quote:
Originally Posted by slimneill View Post
Richie the first car is nice.

The Leblanc Caroline looks like a cross between an Ultima and Schupan the design's a little dated.
I agree with the dated design. I'm sure Fran can come up with a better one .
It could do with some better bodywork, but the underpinning still makes sense.
Small, lightweight and with a compact engine that doesn't bankrupt you at the pump.
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Old 11-30-07, 03:23 AM   #384 (permalink)
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Re: RCR's Next car should be.....

I'm with Grant on this one, but I would want a top on it...to really be used in the rain.
I'm a big fan of the cost, availability and performance of the transverse four cylinder mounted mid-ship RWD.
The idea of a SL-R with a full body for daily use would be perfect for my taste.

Until then I can't wait to see the finished body work for the SL-R!!
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Old 11-30-07, 06:56 PM   #385 (permalink)
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Re: RCR's Next car should be.....

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Originally Posted by gt40fran View Post
We have a very nice T70 spider too, though....wink wink.
The T70 MkIIIb?
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Old 11-30-07, 07:25 PM   #386 (permalink)
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Re: RCR's Next car should be.....

Quote:
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I'm with Grant on this one, but I would want a top on it...to really be used in the rain.
Wimp. OK, ideally I'd prefer a removable top and windshield too. I live close to 2 tracks, and so would probably prefer a simple wind deflector most of the time, but more weather gear would be nice for longer trips to Road Atlanta or Sebring. Still, I'd happily settle for packing a poncho. The biggest reason I want a full-bodied car is for modern aerodynamics - low drag as well as downforce. Sebring and RA don't really favor cars which top out at 150.

There are cheaper transverse British kit cars with roofs (such as the Aeon). The problem I have with them (aside from the exchange rates and the obvious logistical problem of being in England) is that most don't really look to have anything like the quality I've seen in RCR's cars (although the Aeon might be an exception to this). I'm scared if I put a LS7 with a decent cam in one (or something of similar power for a transverse car), it would twist like a pretzel on the first hard launch.

They tend to use riveted aluminum panels instead of the beautiful welded aluminum monocoque, and it seems like I often times have trouble spotting many triangles in their chassis. Fran might correct me if I am wrong, but I believe a problem with riveted panels is that rivets loosen over time, reducing chassis rigidity.

Quote:
Originally Posted by MotecM View Post
I'm a big fan of the cost, availability and performance of the transverse four cylinder mounted mid-ship RWD.
The idea of a SL-R with a full body for daily use would be perfect for my taste.
Is the cost of something like a turbo V6 with transaxle that much less than a LS1 with a 930 4-speed? To me, the largest benefits are the reduced weight and size of the entire car, meaning less money spent on brakes and tires, among other things.

Quote:
Originally Posted by MotecM View Post
Until then I can't wait to see the finished body work for the SL-R!!
I don't think it will have much more than an Ariel Atom.

Last edited by Grant B; 11-30-07 at 07:37 PM.
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Old 11-30-07, 07:49 PM   #387 (permalink)
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Re: RCR's Next car should be.....

Paul....???

No I mean the Mk2 spyder....like the Gurney car or the car that Fred is scratch building
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Old 11-30-07, 08:49 PM   #388 (permalink)
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Re: RCR's Next car should be.....

Oh goody !
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Old 11-30-07, 09:45 PM   #389 (permalink)
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Re: RCR's Next car should be.....

Quote:
Originally Posted by MotecM View Post
I'm a big fan of the cost, availability and performance of the transverse four cylinder mounted mid-ship RWD.
The problem with mid-engine/transverse cars is that they often have an excessive rear weight bias. You can end up with 60+% of the weight on the rear axle and that isn't a good thing. Some designers try to mitigate that with a short wheelbase, trying to get more weight on the front wheels, but that results in a lot of weight transfer coming off the corners and it can result in a lot of power on "push", and the higher the power to weight ratio you have the worse it gets... A proper North/South mid engine setup is really the best thing, as has been proven in countless race cars since the 60's

With all the front drivers around, there are now plenty of moderately powerful front drive packages that can be mid mounted, but it doesn't often translate into a good dynamic package. You won't see big power in a front drive package since torque steer starts to get ugly, but for a very light car, a package laid out around an Audi type layout (overhung front drive system moved to the rear) starts to look very attractive.
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Old 11-30-07, 11:36 PM   #390 (permalink)
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Re: RCR's Next car should be.....

The issue with Audi package is extended wheelbase and minimised ergonomics in the cockpit ....while still trying to accomodate a shorter wheelbase and agile lightweight handling...

There are others trying it but their product can't come close to the value that the $16k SL-R gives....

If the FWD package is canted forward to help increase the weight bias it certainly helps...

In our Electrolite Roadster the weight bias is easily reduced with placement of our battery package...

Porsche has proven over the last 40 years , that a vehicle with a massively high polar moment of inertia can be made to induce smiles per mile and eventually be refined into a supremely capable sportscar...

Isn't the smiles per mile equation what we are all looking for ...???
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RCR-40..Mk1, 2 and Mk4
RCR-70 Mk3b
RCR-70 Spider
RCR-P4
Superlite Coupe
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RCR917
XJ13 for SCF
www.RACECARREPLICAS.COM
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Old 12-01-07, 01:20 AM   #391 (permalink)
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Re: RCR's Next car should be.....

Quote:
Originally Posted by Solofast View Post
The problem with mid-engine/transverse cars is that they often have an excessive rear weight bias. You can end up with 60+% of the weight on the rear axle and that isn't a good thing. Some designers try to mitigate that with a short wheelbase, trying to get more weight on the front wheels, but that results in a lot of weight transfer coming off the corners and it can result in a lot of power on "push", and the higher the power to weight ratio you have the worse it gets... A proper North/South mid engine setup is really the best thing, as has been proven in countless race cars since the 60's
You're assuming you don't want that extra weight transfer that causes more understeer. In a car with a relatively normal power/weight ratio thats probably the case. But take a twin turbo Ford GT for instance; it could certainly use more weight over the rear under acceleration. I've ridden in one which was probably putting down about 1100whp, and it naturally had some traction issues. Granted it wouldn't be making 1000+hp in road course trim, but it wouldn't be too far off (~800 or so).

IMO, on a RWD car that makes good power, on-throttle push is a good problem to have. Its one of the few problems which is easily remedied by adding more power

I would think a bigger reason not to use a transverse engine in a race car is aerodynamics. The ground effects tunnels can split to either side of a longitudinally mounted transmission, like on a 962:
http://962.com/images/image004.jpg
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Old 12-01-07, 10:50 AM   #392 (permalink)
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Re: RCR's Next car should be.....

Fran,

IMHO, the 911 series is a triumph of extensive engineering overcoming what was essentially a really bad idea in the first place (hanging the engine out behind the rear axle). The combination of short wheelbase, and poor weight distribution makes driving one on the track more akin to juggling a sledgehammer than smiles per mile. (and this comes from someone who has a lot of track miles on various Porsches) Not to say that the 996/997 aren't better, they are truly remarkable cars, but few of us have the time or resources of Porsche to get it right (and it took them over 30 years to get it right).

I am fully in agreement that a fun "flingable" car can be made using a transverse layout in a small very light car, it just isn't exactly what I am looking for as a track day car. Just look at the Lotus Elise/Exige, it is a hoot of a car, but it also has corner exit push under power, and it doesn't have a ton of power, if it had more it might be even worse. Having a really sweet handling car with good balance and no vices is, what I am after, and I am just not sure you can do that with 60+% of the weight on the rear axle. You are right that tilting the engine forward, as well as moving as much weight forward can help a lot. The point I was trying to make is that getting the weight distribution right from the start just makes it a lot easier to get the right dynamics without a lot of development.
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Old 12-01-07, 11:58 AM   #393 (permalink)
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Re: RCR's Next car should be.....

Manny.

I understand fully BUT there is not a cost effective way of doing that, to appease the masses...not everyone wants to run an Audi/VW engine and trans....look at the ZF transaxle situation.....if single source parts become expensive and no longer available then bang goes the complete concept...
Obviously perfect engine placement would be sitting next to the driver balancing out his weight..but thats not really a solution either for a dual purpose car...and I know all about the DP1 project for $100k

The cost/availablility of numerous FWD packages dictates the complete drivetrain project........for my SL-R
People still have the opportunity to tailor their car to their taste...SL-R...16k as a full rod end suspension/4 piston braked roller .....keep it simple and enjoy the ride..there is not much else out their with as much personality and tunability with the bang for the buck...and I know a few people that will be smiling whilst driving ....but thats just my opinion...

The SL-R is not a track only car..its a fun car with track ability..if you really want a full on track car with great potential there are tons of used Formula Fords with and without wings that are not competitive any longer that can be bought for under 20k...but when you need tires/parts they are pricey..and you cant exactly drive them to and from the track...but they are a pile of fun..compromise compromise...

Manny, dont you think that every design is flawed in one way or another?

If there was a "perfect" no development required solution we would all be driving one....???...wheres the fun in that...???.Isn't the term "flawed" really called character, charm or personality??
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RCR-40..Mk1, 2 and Mk4
RCR-70 Mk3b
RCR-70 Spider
RCR-P4
Superlite Coupe
Superlite Roadster...including Electrolite
RCR917
XJ13 for SCF
www.RACECARREPLICAS.COM
www.superlitecars.com

Last edited by gt40fran; 12-01-07 at 12:17 PM.
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Old 12-01-07, 12:21 PM   #394 (permalink)
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Re: RCR's Next car should be.....

a 300SL would be great and I'll use my wife's M3 as a donor!

You don't think she has a forum name on here do you?
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Old 12-01-07, 07:52 PM   #395 (permalink)
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Re: RCR's Next car should be.....

Fran,

Right on, nothing is perfect, we all pays our nickel and takes our choice...

Your SL-R is a great toy at a very fair price, and there are lots of other neat things out there too. I kind of lean more toward an RCR P4, myself, just because it is so drop dead good looking.... If I sat in one I might find it not very liveable, but it still looks so good that I am VERY sorely tempted....

BTW your products are great and I don't think that ANYBODY else out there is offering the value and performance that you have managed to put into all your products. Everbody has a mission for how they want to use what they build, and as a result of that there is no one perfect kit for any one person. What is great is that anybody can build what they want and hopefully enjoy it.... I for one am thankful that you got into the business and have created a group of unique and most excellent products....
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Old 12-01-07, 07:55 PM   #396 (permalink)
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Re: RCR's Next car should be.....

Thank you...

my guys and I work hard to keep moving forward...

I build cars that I like and it really is a cool place to come to work...most of the time..
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RCR-40..Mk1, 2 and Mk4
RCR-70 Mk3b
RCR-70 Spider
RCR-P4
Superlite Coupe
Superlite Roadster...including Electrolite
RCR917
XJ13 for SCF
www.RACECARREPLICAS.COM
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Old 12-01-07, 08:11 PM   #397 (permalink)
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Re: RCR's Next car should be.....

Quote:
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Just look at the Lotus Elise/Exige, it is a hoot of a car, but it also has corner exit push under power, and it doesn't have a ton of power, if it had more it might be even worse.
More acceleration only increases rear grip to a certain point, after which it begins to decrease it rather rapidly. I've driven MR2s, for example, that got totally sideways rolling onto the gas out of 2nd and 3rd gear corners.

IMO, it depends on what sort of power you want to make, and how sticky of tires you are goign to put on the car. I think Fran absolutely made the right choice; I don't think a 1200lb SL-R with decent power will have much trouble burning the rears on corner exit. Me, I like powerful cars. I'll take as much weig