I'm not sure what got me on this kick today, but I started thinking about a no-holds-barred unlimited class-type FWD car. No class limitations, no restrictions, let the craziness fly (Ex: Rado's Scion). Not that I'll ever have the funds or motivation to make one happen, but I am curious as to how some of these principles could carry over to a more reasonable car.

My initial thoughts:
-As much tire in the front as is humanly possible. Hoosier 275s are the first thing to come to mind, but I'm thinking with a bigger diameter wheel more is available.

-Get the weight down as low as possible. <2000lbs wet and with driver at a minimum? While 1500lbs or whatever would be wonderful, I don't know how realistic it would be (in a production chassis anyway...but maybe I'm limiting myself too much).

-Blah motor, whatever, somewhere between 300-500 at the wheels.

-Suspension stuff...this is where I start to get lost. Knowing the car will be super light, putting down a bunch of power at the front wheels, I'm thinking there should be some way of doing SOMETHING that would help put the power down. Different geometry? I know we have a few physics wizards here that understand how this stuff works WAY more than I do. Given free reign, what would you do?

-Aero stuff...while the front wing thing may be the answer, I'm wondering what else might work. There was the yellow Derek Bell (?) H1 car on the West Coast years ago, and I remember some decent aero work going into that. Again, I imagine the biggest problem facing the idea of this car would be putting the power down effectively.

-On the aero note, I was thinking about smaller things that would hinder a production-type car. I've seen on some of the other pseudo-unlimited car things like "vented" front fenders, or fenders pulled away from the body where they meet the door. Presumably to relieve some kind of pressure built up there? I don't really know. Similarly but simply, removing the "parachute" effect from the rear end of the car.

Thoughts? Criticisms? Personal insults? All are welcome!

 

Duh I'm looking for alternative ideas and principles they've applied to that car (as so far as I know, there aren't many details available, given that they've spent money on development to be competitive).

 

If its got to be FWD, and weight is not based off displacement, time for the J swap and boost. Sleeved, overbored, one of the longer stroke cranks, 4 liters and 1k+ hp sounds reasonable.

Then go do whatever it takes to fit 305+ R comps up front and copy Rado's wing...

 

How about this: again on the idea of putting the power down, would more weight over the drive wheels help (specifically for that function, disregarding other stuff)? In that instance, would a heavy 6-cylinder (J-series) be a better option than something else?

 

OK World Racing Time attack scion has what 713hp and a tube chassis.
So I see where your getting your ideas from Stinky..
Are we only using a Honda motor here?
What chassis to start with? CRX, EG, S2K, Fit?

 

Just do a S500 (1500lbs) with a Honda motorcycle motor and sequential transmission

 

Unlimited? There's a limit to everything, and FWD's limits are well known - there's a limit to how much power you can put down.

I've seen two memorable FWD racers that provide useful yardsticks. There was a multi-championship winning GT4-5 car a few years back loosely based on the Renault Le Car. It had the Renault/Gordini motor behind a Hewland MK9 - very cool. The other is a GT3 Corrado with a typical transverse setup - it runs on 9 and 8 inch Goodyears and is almost a match for the GT2-3 240SX's.

The ultimate? Mazda 12a rotary behind a Hewland MK9 in an open cockpit sports racer chassis running on 8's and 10's. 95-100 inch wheelbase, driver in the slingshot position. Would be a peculiar beast, but a beast. Low drag. Insanely light. No more aero limited in front end downforce than anything else and easy to do the tunnels. It'd take some creativity in sourcing radiator air and venting engine bay heat but surely "it couldn't be that hard".

Scott, whose actual dream car is already in the shop needing only me to finish it and not dream about something else...

 

You could play with the powertrain idea, something like a larger stroke K-series engine (going off of your stupid giant blue flag chassis) with a well set up manifold/turbo/variable inlet. Drive by wire, sequential box, m800. Basically because i would love to spend the time setting up a road race oriented traction control system with a turbo, motec, and DBW. And lots and lots of datalogging.

As far as the rest of the car, please consult a aero and chassis person. I would imagine that something to the effect of lots of brakes, lots of aero, and tire.

 

I'd have whatever works. That thing that works would have a spray bar setup over the tires.

 

Motor, I'm not too concerned about. In line with the World Racing car, they're putting down 713 to the wheels. That's a lot. I don't know of any other FWD car currently racing (be it Time Attack or otherwise) that's within ~400whp of that number. I'm guessing that's because of the issue I mentioned and that Scott posed again: getting the power down.

CivicSi, I like your thinking I had thought of how to make that work, but (other than your S500 example) couldn't figure out a chassis that was light enough to make it worthwhile. The lack of torque on a bike engine would be problematic I'd think for something heavy.

If I really wanted to be realistic in this completely unrealistic idea, part of me would be starting with a common, basic Honda chassis (Civic, CRX, etc.). That would simplify things I guess. At the same time, I don't know that I want to confine myself the same way.

Scott, you mention "Sports Racer" and FWD in the same post. Is that accurate? Short of the GT-x cars I haven't seen anything like that FWD.

 

Harold Noble's b16-powered Mini comes to mind...though I'm not sure you can consider that a production-based chassis anymore and keep a straight face.

 

Yeah but regarding the world racing car, I can almost promise you they are using some type of boost control that is set up track by track relative to speed or gear. So for example coming out of oak tree, they are more than likely NOT in 2nd or 3rd gear putting down 700whp. That would be a fantastic burn out show, but nothing useful.

You should build around the engine in my opinion, everything on the chassis (brakes, aero, spring, etc) is relative to how much power you plan on making one would imagine.

 

http://www.rileytech.com/PDF/GT.pdf

One of those, setup for a front engine Comptech DP motors (http://www.comptechusa.com/style/new...Honda_DP06.JPG ) with a custom sequential Xtrac. Mount the motor longitudinally with the trans IN FRONT of the motor at the center line of the front wheels. (picture what you see in the dp above but with the *** end being the FRONT end) with a Acura TL Carbon Body.

That comptech motor should make around 400whp maybe more i don't know.. and that is plenty. this isn't drag racing and usable power is MUCH MUCH more important then all out power.

Tires and wheels 18x9 or 18x10 with Michelin Slicks.

The suspension on those Rileys is simple and good. Get a good chassis setup guy, and some 4 way penskes.


Design and change the front end of the TL so that it creates some down force, while keeping the basic shape and style.

That thing would be wayyy fast

 

That is friggin' cool... and right along the lines of where I was going.

So usable FWD power, what's the limit? If Rado is getting away with ~700, why stop at 400? Does that 300 make a difference? I really don't know. Is the extra 300 just on tap for straights (like Sander mentioned, with variable boost) to turn straights into a drag race?

 

In production cars, i think 300whp is right around the max. It seems it has been that way for years. With Super Touring in BTCC starting in 95, JGTCC touring, BTCC in current times, and WTCC currently. All of those series have always had the HP at around 300hp. From 95 to now technology has came a long way, but HP has stayed the same. So I am making a guess that this number is around the cut off point for FWD

Why only 400whp? (that was an approximate guess the DP motors make between 400 and 500whp my guess, so maybe that motor makes some were around there.

IMO useable power is much much more important then that high HP. To win a drag race on a road course corner speed, exit speed are much much more important the HP. I'd bet that rado's car is rarely ever using more then 500HP.

And I feel like that car i described would be fast as ****. Probably would be able to hang with the Rolex GT cars for a few laps. There isn't ANYTHING in time attack that can run lap times close to what a Rolex GT car does. And when everyone is in amazement of how fast the car is you could say "yep and it only has 400whp".

Most of the Unlimited TA stuff i have seen is 500whp plus. So you'd be kicking everyones but with way less HP.

Which is a huge bonus.

 

Interesting. That would make this whole idea more realistic and simple, rather than the completely blank page I'm sitting in front of.

Also curious: why a TL body? Good aero starting point or something?

 

I did. It is. I haven't either. It's not a "good" idea - unless you're trying to build an unlimited FWD device. Why 400 or 500 or 700 hp to push around a wall of air. 250hp, 1200 lbs, an extremely low cg, less than 18 sq ft of frontal area, and tunnels would be hard to beat...in another FWD device.

Scott, who could give up FWD easily if I had anything other than my current ride...

 

I would LOVE a class like this. I'm doing time attack simply because there isn't a high HP FWD class. IMO this would be an EXCELLENT way for the Redline series to expand into something more than just time attack, although I would love NASA to have the series as well.

Also, who cares what #'s people put down. I say put down a weight limit, some basic rules and let the track find the winner.

Where do I sign?

 

That is correct. I asked Chris that same question last year when he was PIR and they have a boost controller on the tc that limits boost depending on what gears he is in. IIRC he "only" has 300 or so whp in 2nd and 3rd gear. As he gets into 4th gear and beyond, the computer allows for more boost progressively with each gear as traction becomes less of an issue. The car tops out at 500 and some whp.

.....that is until he hits the 'scramble' button on the steering wheel which maximizes the boost and tune for maximum power, regardless of what gear he is in, and gives him an extra 100 or so whp to the 700hp mark.

 

Wouldn't TTR be the same thing as what you're talking about?

 

With the tires providing the acceleration, deceleration, and lateral acceleration, isn't this the place to start

That said, I'm thinking some active aero along the lines of air brakes and a two piece automated splitter to keep the inside planted on those high speed corners