crash41301

iTrader: (1)

Rx7's weigh 2500-2800 lbs stock. Lighter once they start removing the huge cat convertors and monster mufflers that come on them to make them OEM silent.



I've had 3 miatas, and a buddy that loves his fiero that I help him work on and play with. Changing the steering ratio will absolutely NOT make it rival a miata. Polar moment of inertia would have to change to do that. You will actually be making the PMI worst with the big tranny and ls1.

I *think* you mean 2nd gen MR2, which were around 2800lbs. The 3rd gen MR2's (little roadster things that looked like half retarded boxsters) were like 2200lbs stock.


Nothing against this swap, as I like my buddies fiero a bunch too. I just think you should listen to Lowerit as he IS right.

That being said, good luck and make sure to post pics

Lowerit

Ohhhh The dreadful Miata...

If you are trying to buld a fiero to compete with a Miata ...

Don't


I see someone mentioned a ""cheap investment"" of $1300 and the car does 1.1G's on a skid pad.... How bs travels.

The guys name is Cali Kid
his Fiero has some L98 he passes off an a Lingenfelter motor.

The car has Koni's and Cut factory springs. he hit 1.1G peak using aGTec.


The fiero is a dinosaur when it comes to autocrossing.. Sad to say my 66 Corvair will run cirlces around my prepped Fiero with ease...

Save your money... Buid an LS1 Miata , or a locost if autocross domination is your goal. so many people have been down the road you are on and have eneed up with a tempremental car that can be beat by most modern FWD cars with 1/2 the power.

Fiero.nl and it's cronies are not a great souce of information.T hey are really biased. Join the Fiero racing list
and ask ont here before you spend tons of money.

The fiero just isn't competitive.. it's lethargic and heavy. The Top Fiero autocrosses (if there are any left) don't use the held suspenion or any of that BS. it's shiney tube frame peices that use the same basica mounting points...

Changing the suspension out , or adding more power won't change the fact that a Fiero is a brute.. it's not a car you can autocross smothly and confidently.

J.M
Autocrosser of the following cars.
02 Mini cooper
911 RS america
97 M3
997 S
corvairs (v8 and 6cyl)
Fiero
02 Civic
89 Civic Si for GRM $2008 challenge

Trust me ...save your money.

darkhorizon

Fieros are fun for straight lines though!

My fiero runs 12.8 with a stock V6 I pulled out of a junkyard for $400.

Tainted

iTrader: (9)

Id actually say talk to Patrick G and ahve him spec you a cam to suit your needs and maybe jsut rework some 241 heads or some lightly worked on LS6 heads. that should be plenty of power assuming youve got the things to match.


OR if you really wanna get intresting, how about a ncie Lotus Elise with a beefed up motor? thatd be a VERY fast track car with everything already set up

Ravant

Curb weight. Put a full tank of gas in there with a 168 pound driver. Gas weighs 6.5 pounds per gallon, and the RX-7 has a 14.5 gallon tank. The absolute lightest an RX7 could be, stock, with a full fuel tank and a 168 pound driver is 2762 pounds. That's using your low estimate of 2500 pounds for a curb weight. The FD weighs 2625, so adding the full fuel tank and a 168 pound driver, you're looking at a 2887 pound race weight. Stock.

The F40 weighs 20 pounds less than a Getrag 282 and the LS1 weighs almost the same as a stock V6. Don't forget, stock V6 is all iron. LS1 is all aluminum. Precisely why the "Toy Jet" Porsche 911 drops 21 pounds off its stock weight. The LS1 weighs 56 pounds less than the stock Porsche 3.0 liter engine, whereas the cooling system used for the rear-cooled setup is 35 pounds heavier, making for a total of 21 pounds dropped. On the Fiero, you lose weight from going from the TH125 going to the F40. (Newer, stronger, lighter materials.) You stay about stock for the engine. (Roughly 5 pounds less, actually.) You go to an aluminum multi-core radiator in the front, dropping 8 pounds up front as a result, retaining mostly stock cooling lines. If anything, you make the PMI better with the lighter tranny and marginally lighter motor. The other option for an engine swap was a turbocharged L61 Ecotec I4, or a turbocharged LE5 Ecotec I4, which drops the weight at the rear of the vehicle by 30-45 pounds (30 for the LE5, 45 for the L61), not including the 20 pounds lost in going from a TH125 to an F35 transmission. But the difference of 45 pounds was negligible when looking at the change in suspension geometry and tread/track width, which both make more of a difference in handling than a simple 45 pounds that I'm not going to remove from the back of the vehicle.

No, the 1.9 lock-to-lock isn't going to change the PMI, but it is going to change the necessary amount of motion I'll have to go through to execute the turns as necessary.

2200 if you ran with no body panels, transmission, or interior. Race weight comes closer to 2500 pounds. And the body lacks any kind of rigidity to handle very well, compliments of its convertible nature, which is why people tend to use earlier-gen MR2's for their projects.

Why does this build have to end up with me competing with anyone? It's not.

That clearly is BS, considering the suspension setup I'm switching to is hardly going to be $1300. It's going to enter close to a $5,000 range. Roughly $3,000 for the front, roughly $2,000 for the rear. Possibly slightly more, depending on if I decide to widen the track width by 1.5" per side on the front and 3" per side on the rear.

Personally, anyone who runs cut factory springs, IMO, is not lending themselves to "great" handling in the first place. If this is what you're comparing my build to, I think I should be insulted.

I'll ask again - what kind of preparation has the suspension received on the Fiero?

So many people have also stopped at coil-overs alone and expected those alone to change the suspension enough to get amazing handling.

The Held suspension package, not the simple coilover suspension system, but the complete setup entirely changes the geometry according to Lee, the proprietor. He's built suspension systems to see a w-body land-barge into the 1 lateral G ballpark, and to claim his top-end products are "BS" is BS in and of itself. The tubular arms are lighter than stock, reducing unsprung weight by a decently drastic amount. Anyone who knows suspension tech will tell you that unsprung weight is the #1 enemy to good handling. As for a Fiero being "lethargic and heavy", in comparison to what? It's lighter than a C4 'vette, and handles better. It's lighter than a C5 'vette, and with coilovers, handles better. It's lighter than a C6 'vette, and with a full suspension package, handles as well as the C6 base with a Z51 suspension package. It makes the Evo seem sloppy around the turns, even stock. It makes the STi seem outright sloth-like in the slalom.
Once again, I ask the same question that you've avoided twice now. What exactly have you done to your Fiero's suspension to give it a chance in comparison to other vehicles? Coil-overs alone? Coil-overs with tubular control arms? Or have you bothered to actually dig into the chassis and actually change the track width and suspension geometry? Running stock width tires? Or are you running wider tires on all four corners? Running the same 195mm stock tread width in autocross that the car does stock on the street after changing the suspension is like conditioning one's body to play basketball on a pro-level and only coming to the game in only socks. You'd be sliding around just as much. I'm looking at 315mm rear and 245 front, running 3" wider track width in the front, 6" wider in the rear. To say that this is like every other Fiero wannabe autocrosser that runs coilovers and cut springs is frankly, a fallacy.

Honestly,
1) I don't know why my build is being attacked. It's better than, say, RWD-converting a w-body Monte Carlo and going with an LS2/T56 combo for a cost-effective autocross vehicle. (Though, in FWD form, one can be made to run a 2:35.18 lap time at Watkins Glen International. Not exactly pacing a C6 Z06, but it's not exactly sitting back with the guys in the Mazdaspeed 3's either.)

2) I'm not sure why this thread got side-tracked as far as it did. I came here looking for advice on how to bring my crank power output from 350 horse and 365 ft-lbs of torque to ~480 horse and ~460 ft-lbs of torque, with a flat, broad powerband, avoiding as many peaks and sudden increases/decreases in the powerband as possible, and suddenly, I'm being attacked for taking a decent chassis and re-working it beyond what 90% of what most people do. No, I don't have pictures. No, I don't have proof. Neither can materialize until I get the information I need to move forward with the build. It's like trying to build a bridge without the budget. I get the info, I get the parts, I disappear for a while to do the build, putting everything together, taking pictures/video the whole while, come back with a completed project, and a full write-up on what I did/how I did it, and include videos of the performance. That's about how the progression works. With people nit-picking and attacking the build instead of just answering the damn question, the rest of the progression stops. I appreciate the "trying to help" sentiment, but it's not helping. It's getting in the way of the answer.

Lowerit

dood , I am not attacking you at all..>I am putting an LS1 in my Fiero and It will see track days..ijust won't compete with it. anyone can make a miata fast.. I am just trying to help you realize that it won't be competitive on a national level.

I have revalved Koni yellows it the rear (and front)
Poly all around
Carrera Springs (500Lbs rear) from Stockcar products.com and their sleeves
Front is a custom Coilover setup
camaro 11.25" discs
blazer Master Cylinder
Rear tie rods are heim'd
1.25" rear (custom ) bar
1" front bar
removed steering damper
235/40/17 Pirelli P Zero C's Front
265/45/17 P Zero C's rear
Spec Stage 3 Clutch
Aluminum Flywheel custom from spec
Holley commander 950 (sold it)
5spd Built by the same guy who did our 930 tranny (cavalier)
dickman Shifter brackets and cables.
Solid mounted motor
Short Shifter
Sparco's

Ravant

I don't mean to sound dick-ish, but that's really not much on the suspension. Just coil-overs and sway bars. You didn't touch the control arms, the mounting points, or change the angle at which the suspension compresses. All of these add to maximizing contact rubber when turning, hitting bumps, or otherwise just driving. A set of sway bars and coilovers will not take a car that is only capable of 0.88 lat-g's stock, and put it above the 1-g mark. Especially if you're over 450 pounds as a spring weight. Research shows that 500's even too stiff for the C6-R, They run 450 front, 475 rear on most occasions, going softer for tighter courses to maximize suspension usage to keep as much contact rubber on the track as long as possible.

Running 315/45/17's on the rear, and 245/45/17's on the front with a fully redesigned, purpose-built front suspension using lightweight materials and construction principles, combined with an '88 rear suspension with tubular control arms, the change in track width, and the significantly wider tires for traction purposes is not the same as running coilovers and sway bars with stock track width.

The only competing I intend to do with my Fiero is competing against my old track times set by my W-body up at Watkins Glen. Seeing as it ran a pathetic 2:35, that shouldn't be too hard. Even a stock GT should beat that. Hell, a good driver with the 'sport' gearing on a 2m4 could probably out-do that.

mad max motorsports

In SCCA this will be a street mod 2(seat) class (SM2) and should do well.
I am competetive in my area with my '88 formula in my street tire stock class. It is a tough fight with the MR2s (as it should be) and the 1.8 Miatas.

There is a local Fiero GT with a turbo 3.4L "twin duel cam" putting down 415 to the rear wheels. According to the owner at the "dyno day" he ran a traction limited 12.3 in the 1/4 at 126mph.

I say do it and have fun with it.
See if you can get the IMSA wide body for it with a vented hood, high pressure builds up under the front area with out it.

Lowerit

my suspension isn't that serious.. But is all that **** legal in SM2?? Im sur it willbe a fast car...but if you think you are the first to head down this road , or it's some monumental build ..you are wrong...and about 10 -15 years too late.


it's all been done my friend.

Ravant

Not saying I'm the first, and I'd hope not to be the first, because usually - the first is all prototype material. I'd rather be one of the last, to know I got refined and proven material.

I'm not sure how much of the modification would be allowed in competition class vehicles, but once more, the car is only being built to allow me to personally attack my own times and to run for fun, to also prove that an American mid-engine chassis can be competitive with a relatively low amount of cash forced into it. I've seen plenty of cars with $45,000 or more invested, to get the same performance I'm going to get for under $30,000.

Not sure if I'm going to do the IMSA wide-body kit yet, but rather a custom body and hood. The stock drag coefficient is ugly, and the notchback without the aero nose generates 120 pounds of lift at 100 MPH, so that's gotta change as well. What may end up happening is, I'll probably get a Fino kit, and do some cutting and fiberglassing on my own to accomadate the extra track width. Already am familiar with the pressure build-up under the hood, though, had the headlight doors spring up on me at a paltry 95 MPH, whereas most people have them pop up at higher speeds.

As for the guy running 12.3 with 415 rear wheel horse, is he running 195mm rear tires or something? I've seen guys with the L67 3800 run 11's and better with less power at the wheels.

mad max motorsports

My headlights pop up at about 110 to 115mph but I have rebuilt them.

That under the nose pressure is where most of the lift comes from, if it was legal in my class I would get/make a vented hood.

He was on street tires (non-drag radials) close to what appeared to be about stock size.

I was getting 2.0 60ft times in my car on 225 BFG G-force KDs with only 120 at the wheels.

Ravant

Yeah, my doors are pretty worn out. I could manually lift them with two fingers. That's not normal, apparently.

Couldn't you create some vents that would push out the pressure from where the hood closes? There's a bit of weather stripping up top, and if you duct the air and remove the weather stripping in some places, you can relieve the pressure while maintaining a full stock look.

That explains a lot. The guy with the 3800 S/c I saw was running 388 at the wheels, but had 245/45/17's on the back. Street tires, but much wider than the stock 195's.