With all the posts on raw power, I thought I'd ask something a little more finesse oriented?

Well, the new Enzo Ferrari turns 1.3+G on *street tyres* from the factory...

How do we beat it?

Best!
Ben

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Ben Cannon
88 Formula, T-top, Metalic Red. (2:13.138 at Sears Point) "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver, In-Progreess. -Mel Gibson, "Braveheart"

Hmm. Get a set of the same tyres that is used on that car and I bet it gets closer.

I don't know how to find that other .5 Gee's

Hey Ben,

What about Held's slalom suspension? He claims it's good for over 1G with street tires and spring rates - imagine the possibility with the slalom/auto-x setup and the stickiest street tires available! That is probably what the Enzo is running. After I get my car sorted out I may just have this exact setup on it.

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http://phitown.com" TARGET=_blank rel="nofollow">http://phitown.com

Steal the suspension design and knock 1000lbs off the weight.

Good question.

But I'm not sure that it makes that much difference ... at least to me.

Lots of difference between .5 lateral G of a 5-ton Army Truck and the .79G my Minivan does. My Old Vega was supposedly .85G from the factory. My now FIero (WS6, 85 SE) supposedly only has .79G stock but shocks, tires and 'tinkering' may have put that over the ".85G" the old Vega used to have by "Ass-o-meter".

I don't have any roads that would require THAT much "stick" ... as the Fiero outdoes everything I run into.

OF Course "Bragging Rights" are always a desirable goal.

???? Same old question:
"Speed (etc) costs. How fast can your wallet go?"

8.2G

Well, lessee...
a)as said above, lose some weight overall.
b)alter car's axle centerline, in the verticle plane, relative to center of mass
c)in keeping with (a), replace fenders and hood with lightweight one-piece front cover: this one having slots to vent air whipped up by tire rotation, and venting for radiator exhaust, coupled with improved lower front sculpting for a bit more front downforce. I suspect the spaceframe would have to be cut down a bit.
d)widen track up front, and use wider rolling stock
e)buy a GT40, and install Fiero decal pegasus emblem

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my cat's sitting in my scrambled eggs.

Ben, I'm quite interested in your topic. I like Ali's post. If you widened the track front and rear, you would "have" to widen the body. Seems like a good opportunity to make a lightweight fiber glass (carbon fiber would be better, but I don't even have enough money for fiber gass ) one peice clam shell trunk cover and rear deck. While you're widening the tracks, make new front A arms and change the 88 cradle rear suspention (we're not using the 84 - 87 cradle, right?) to something, um, better.

A big project for sure.

"If you widened the track front and rear, you would "have" to widen the body"
My thoughts exactly, John!
I agree about the rear suspension too, imperfect though it may be.
We're trying to make the Fiero into a LeMans Prototype - which is fine with me, if it's possible.
My username refers to my original idea to paint my project 85GT powder blue and orange like the Gulf 917s. Unfortunately, when i modeled the car in Photoshop, it looked horrid.
Oh well, back to the drawing board.
My GT is going to receive a center post mounted dual-element rear wing like the 333SP.
If i can
a)afford it
b)find somewhere on the cradle to mount it.
doo dee doo...

Easy! (but not cheap )

Start with a Huffaker SD4 Racing chassis,
Then an SD4 Race engine.
Then use the same designed suspension as the Enzo.
Toss on the IMSA race body.

Have Fun!

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Happiness isn't around the corner...
Happiness IS the corner.

personally, i'm into building up a boulevard bruiser, with a killer stereo, all black leather interior, and a nice big rumbly V8.
I want to keep the 85GT body stock, except for that weak wing, and just make it realllllly pretty.
My above mentioned 333-esque wing will be my one concession to the I'm-gonna-pound-on-some-rice philosophy.
Ben's all 'bout the autocrossing.
I'm all 'bout looking reallllly mean driving to the track to watch Ben autocross.
(i would if i lived in California)

meowmeowmeow

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my cat's sitting in my scrambled eggs.

Give me you silver car, $10K and a TiG welder, and it'll pull more than 1G.

I've measured the geometry of the Held Slalom setup. It's better than stock, but it's really not that good. I'll do better when I get around to building my own suspension.

Conventional wisdom regarding roll center, camber curve and anti-dive/squat aside...

If you mount the inner pivot of the lower control arm ABOVE the inner pivot of the upper control arm, then you can set things up so that the roll center and CG coincide vertically. The car would have ZERO body roll even without anti-roll bars. It could then be sprung soft enough to ride like a Cadillac, but still corner like it's on rails.
However, removing the roll moment removes most of the suspension's tunability, since that's what suspension tuning is: messing with roll moment.
Basically the only way to tune the above described X-arm suspension is to change tire widths.

Anyway, TIRES, TIRES, TIRES!!! With race tires being the only mod, showroom stock race cars pull over 1G... with rubber bushings... and factory shocks.

Hmmm... I thought the Held setup was the hot ticket, but it doesn't seem to have the Fiero community's undivided attention. So...

How about designing a crossmember and rear cradle that would accept C4 or C5 suspension components. Then use full externally adjustable coilovers at all four corners. Besides gaining what has been described as "world-class" car suspension, we would also gain the exotic aluminum arms.

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http://phitown.com

[This message has been edited by perkidelic (edited 10-08-2002).]

The biggest problem is the Fiero's stumpy wheelbase and excessive weight/length ratio.

Weight reduction would have to be the first job. If you can shed 300 lbs or so that would help. Also, start with an '88. It doesn't have that crappy X car rear suspension which is totally hopeless. The '88 rear has very long torsion bars but I would be inclined to lengthen these by 1 inch each. the room is there for it. I would also increase the diameter of the rear anti-sway bar and design some mechanical end-links (no rubber or poly). Next, increase the length of the control arms both front and rear and get a set of high performance rims with wider offsets. Lower the geometry of the ride by 1.5 inches and add massive tires (tyres to you British folks). Coilovers would be a must and forget your street comfort.

It can be done.

quote Originally posted by Will: I've measured the geometry of the Held Slalom setup. It's better than stock, but it's really not that good. I'll do better when I get around to building my own suspension.

I always find it funny when people claim 1G+ on their fiero because they....

Bought 5 grand in aftermarket suspension that is marginally better than stock

They put eibach springs on it
They chopped their springs

Nice to see that someone else has a grasp on reality and the effort it takes to attain a 1G plus car , let alone 1.5G's.

The fiero is mighty portly to be hitting 1.5G's

Straight tube frame car with longitudinal engine install. 4.6ltr aluminum block olds/buick engine , hewland /zf or 911 tranny.

18x11's rear with some sticky meats
18x9's front.

Think of the money you could spend..

anything that is close to a 1.5Gs is going to be far far from a fiero mechanically speaking. IMHO.

JM

every GM car owner should know JIM HALL
copy his sucker car [a 2stroke fan motor in the rear to suck out the air under the car] with real ground efx skirts and ducks
then add a variable position wing way up over the car.
next alloy or Ti a-arms in front and links in the rear, real wide mag wheels with racing slicks pre-heated to operating temps.
then gut the car removing all unnessary parts
NOW you will have a il-legal to race non-streetable car that may get up near 1.4 G on a skid pad but wil be un-useable for any thing else.

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Question wonder and be wierd

[This message has been edited by ray b (edited 10-08-2002).]

what dose a 333sp wing look like? and how would you mount it to the cradle? would it stick way out the back and connect to the rear of the cradle somehow, or come down through where the trunk would be (or would have been)?

this is kind of what i was wondering in a thread a few days back. when i was asking about funneling all the air that goes through the radiator out of a hood vent/scoop.

say i did this just to see if i could improve skidpad numbers. how fast do i have to be going for any aerodynamic improvement i attempt (for the nitpickers... i said attempt. not saying i have an aerodynamics lad in the back yard. more like possible improvements as part of a styling change) to really come into play.

also, suppose you have a potentially functional wing (or at least high enough to be effecting airflow around its self). how well mounted would it have to be to the car to be functional? i though i read once that a rear wing that is really exerting helpful downforce would have to be stronger than fiberglass (or at least reinforced) and possibly chassis mounted.

just stuff i'm wondering as i play with my choptop.

sorry one more...

what if you have a convertible? would the top being gone and the undercar bracing help? in terms of lowering the center of gravity i mean. even though i'm not happy with the amount of bracing mine has it still seems to do pretty well on the highway exit/entry ramps, considering it has the least aggressive wheel/tire combo of my 3 driver fieros and is still at stock height.

[This message has been edited by Philphine (edited 10-08-2002).]

I've pondered the same question. Ive got a 85 2m4. It's no speed demon but handles very well. Bushings are one thing I want to replace. As well as the usual shocks,springs,swaybars,tires. I think my car after these mods will preform as well or better than a stock 2000 corvette. Not as fast, but the sticky factor should be fun. If you want 1.5g's spend some cash on the right parts, and then spend some time tuning. Thats right tune your suspension. A cars handleing is similar to speed performance mods. They work better with time and patience and a little elbow grease. let us all know what happens with your mods....Erockrocket

Why don't we just wait for the C7 Corvette?
Rumor has it it'll be mid-engined.
it'd save me a lot of work on my Fiero,
but it'd probably make the cost of a current C5 seem but a trifle.

Will
I'm all ears... please tell me the measurements you've made and how I can improve my product for the good of all performance-minded Fiero owners.

We are all after the same thing and if you can supply me with the deficiencies in our components, I would love to change them.
Sincerely,
dave

links to Jim HALL's Chaperrals race cars
http://www.geocities.com/CapeCanaveral/3098/chaprral.htm
http://www.eng.vt.edu/fluids/msc/auto_c.htm
http://www.jackbrabham.com/Hall/hall.html
http://www.vintagerpm.com/chaparral_history.htm

BTW the wing mounts to the a-arms not to the body so loads go directly to the wheels not on the body thru the springs

[This message has been edited by ray b (edited 10-08-2002).]

quote Originally posted by dave@heldmotorsports.com: Will I'm all ears... please tell me the measurements you've made and how I can improve my product for the good of all performance-minded Fiero owners. We are all after the same thing and if you can supply me with the deficiencies in our components, I would love to change them. Sincerely, dave

I'd love to, but I don't currently have any specific suggestions. Flight school takes up a good chunk of time.

The stock suspension goes from -0.5* camber to +4.5* camber with 5* of body roll. The roll center height is constant just below ground level, and moves outboard by less than 1/4 the width of the car. The roll center stability is the result of the parallel control arms close to the same length. Of course this trades off camber control for roll center stability.

The Slalom setup goes from -0.5* to +2.3* with 5* of body roll. This is a significant improvement over the stock setup, but sacrifices roll center stability. The roll center starts off just below ground, but moves up and inboard until it is outside the car's footprint.

The measurements I have were taken from an installed suspension on a car to which I do not have immediate access using a tape measure, so they may not be exact, but they're pretty darn close.

I haven't had the time recently to come up with a good front suspension design, but I have an SLA conversion for the '88 rear which goes from -0.5 to +0.5 with 5* body roll, while keeping the roll center within an area the size of your hand. It trades off roll center location for roll center stability, though. The roll center is about 3.5" above the ground.

This may seem like a lot of body roll, but that's the way I want to run the numbers. Pulling 1G on the skid pad is nothing amazing. Stiffen anything and put sticky tires on it and it will pull 1G.

Building a car to ride like a Cadillac and still pull 1G on the skid pad is the challenge.

You undoubtedly have far more experience than I at actually building these things, while I'm still in the experimental phase. I'd love to pick your brain about suspension design.

[ramble]

I once stuck my head under the back of a previous generation M3. It had very long control arms, almost half the width of the car. Their inner pivots were very close vertically and horizontally. IOW, the design almost acted like a swing axle.

Comparing this to Indy car suspensions and doing some messing around with Racing by the Numbers, I see a few things: The control arms are long, the upper and lower arms are very close to the same length, vertical position of the pivots is more sensitive than horizontal position, and the inner pivots are lower than the outer pivots. Applying these ideas to my SLA conversion, I came up with a design having the characteristics I mentioned above.

[/ramble]

Thought I'd throw in a "smart" comment for Will, but saw after I sumitted it that he said in a later post that he used that software so it wouldn't have been too funny.

well, now that I'm wasting bandwidth, want to share your data files? I've been too lazy to manually enter stock mounting points in myself(and don't have an 88 to get data from anyway).

[This message has been edited by Howard_Sacks (edited 10-08-2002).]

F

quote Originally posted by Will: Where did you find the 1.3G number?

The 8/12 Autoweek article says that the number is 1.36 on a 400 meter skidpad.

Quote by Leper
Steal the suspension design and knock 1000lbs off the weight.
Actually the weight of the Enzo is almost 500 pounds heasvier than the Fiero at 3006#.

The tire sizes are 245/35ZR-19 frt and 345/35ZR-19 rear. The The cars' front and rear air tunnels, full length body pan, active rear spoiler all aid in generating a aero load of 990 pounds downforce (twice that of an F50) at 135 mph.

The engine is great at 660hp @7800 rpm and 485 lb-ft @ 5800 rpm and weighs less than 500 pounds.

None of this is unachievable, Ben. Particularly when you consider that you can go buy an 88 Coupe for say a $1000 and still have $669,000 left over to play with.

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Notchbacks Rule
84 Coupe(parts car)
85GT(show car)
87SE Gold(project car)
87SE Silver(daily driver)
88Coupe (daily driver)
88Formula (daily driver)

quote Originally posted by Fierobruiser: The 8/12 Autoweek article says that the number is 1.36 on a 400 meter skidpad.

400 METER skidpad ?!?! Good golly, no wonder it pulled 1.3. It must have been doing 150.

What about 300 ft skidpad numbers, in which aerodynamics don't play so much of a role?

F40: 2300lbs, 475 HP, 4.84 lbs/hp
F50: 2700lbs, 520 HP, 5.19
Enzo: 3000lbs, 660 HP, 4.54

Why does the ultimate sports car keep getting heavier?
Ferrari will never build anything to beat the McLaren if they don't keep the weight down to 2500lbs or so.

Anybody know HP and weight for the 288 GTO?

400 hp
1160 kg (2557)lbs

about 6.4 lbs/hp

I'm guessing the added weight is coming from concessions to luxury or from safety regulations. Or a combination of both.

This was on a wide skidpad (yeah, I bet it was bookin!) so downforce played a large role.

Still.

Damn.

Great thoughts guys, keep 'em comming!

Will: won't an 'x' suspension throw centre of roll ALL over?

Best!
Ben.

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Ben Cannon
88 Formula, T-top, Metalic Red. (2:13.138 at Sears Point) "Every Man Dies, not every man really Lives"
88 Formula, Northstar, Silver, In-Progreess. -Mel Gibson, "Braveheart"

So how about posting the RBTN data files Will?

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quote Originally posted by artherd: This was on a wide skidpad (yeah, I bet it was bookin!) so downforce played a large role. Still. Damn. Great thoughts guys, keep 'em comming! Will: won't an 'x' suspension throw centre of roll ALL over? Best! Ben.

But that doesn't matter because there's NO body roll. You'd need a load levelling shocks/springs to keep the ride height where it should be or the suspension will be way out of whack, but that's the extent that you worry about roll center.

I'd rather not post the files just yet. Like I said, I'm still in the experimental stage and I'd like to do more fine tuning.

I appreciate your curiosity, though