Hey Fellas,
I am going to turn my 86 SE into a trackday car.
Mostly just to out and do open trackdays. I have a nice set of 15" lace wheels and was
wondering what the best tire for that rim + track would be?

Cheers
Bernie

------------------
Thanx
Bernie
'86 Fiero 2M6 SE, Man
'85 Porsche 928S AT
'82 Honda CX500 Turbo
TheDIYgang-click me!

How much experience do you have doing track days?

Plenty,

Willow Springs is what consumed the last engine in my Fiero!
I am also a control rider for a motorcycle track club running a Kawasaki ZX-7R racebike.

Why do you ask?

Cheers
Bernie

My experience is old and goes back to slalom racing in the '70's however, the theory stays basically the same.

You want sticky, and you want low profile. Smaller radius means more torque and more accelleration. Lower profile means lower center of gravity.

50 series, 195/50R15 would probably do fine. Sounds like fun too.

Arn

quote Originally posted by Bernie: Plenty, Willow Springs is what consumed the last engine in my Fiero! I am also a control rider for a motorcycle track club running a Kawasaki ZX-7R racebike. Why do you ask? Cheers Bernie

Your skill level affects what tire I'm going to suggest, because if you were new I would strongly suggest staying on a good street tire. After a quick look at the tirerack they have the 225/50-15 Victoracer V700 on sale, $145.00 or you can go with the better in just about every way V710 at $180.00 each. Since your not competing price and longevity are the most important. The Victoracer wears pretty good and is cheap. The V710 doesn't last quite as long but gives hero level grip.

Cool,

I checked The Tire Rack this AM and all I found were Hoosiers.
With this info, I can hone in on the right selection.

Cheers
Bernie

Bernie:

I remember communicating with you about a track car, but that must have been at least three years ago. I seem to recall seeing a picture of your car at Willow Springs, but have never actually met you, or seen your car at the track.

Before I attempt to give you my opinion, it would help to know what your are currently running; e.g. year; engine; trans; suspension mods; brakes; etc.

I have run the Fiero roadster at Buttonwillow and Willow Springs (both Streets and big track). I might be able to give you some direction.

------------------
FierOmar

quote Originally posted by FierOmar: Bernie: I remember communicating with you about a track car, but that must have been at least three years ago. I seem to recall seeing a picture of your car at Willow Springs, but have never actually met you, or seen your car at the track. Before I attempt to give you my opinion, it would help to know what your are currently running; e.g. year; engine; trans; suspension mods; brakes; etc. I have run the Fiero roadster at Buttonwillow and Willow Springs (both Streets and big track). I might be able to give you some direction.

Hey FierOmar,

Yea, I am still alive and kickin'
Those were the last days for the ole Fiero as I blew a headgasket.
I replaced the motor with a used one that I bought from a fellow here on the forum. I had intended to turbocharge it and then
got distracted by many many other projects. I built 5 motorcycles over the last couple of years and the Fiero just sat outside.
Well after a few short work sessions with it, the ole girl fired up today!
I have been doing exclusively motorcycle trackdays now for 2 years about once a month, mainly at Buttonwillow.
After the Fiero quit, I did a few more days with my Porsche 928 but I didn't feel like beatin' up on it anymore so then went over
to motorcycles.
Now I want to get a car back out on the track and since the Fiero is just sittin' there, thats where I am going to start.
Ultimately, I will get another 928 as a track only car.

Just want to get a half decent set of track tires since it will take a couple of days to get back up to speed in the car........I think?
I have a set of lace wheels that I had sandblasted and powdercoated so I am going to use them for now.
Suspension dropped about 1.5" with a set of sport springs.

I am working on the brakes at the moment as they have sat for quite awhile. Got the clutch and shifter dialed in today and ran her
for awhile ................ can't move it yet though.

Anyway, nice to be back!!

Cheers'
Bernie

Bernie:

So, the engine is a stock V6? 4 speed trans?

IMHO, I would want to do the following to make a decent track car:

1. Upgrade brakes to Beretta/Grand Am at the minimum;

2. Add the RCC bump steer kit;

3. Consider replacing shocks (KYB aren't too tough on the budget);

4. Replace all control arm bushings with poly;

5. Replace all cradle bushings with aluminum or at least with poly;

6. Stagger the front and rear tire sizes.

7. Don't forget a good 4 wheel alignment.

As for tires, th 225-50-15 Kumho VictoRacer will work. We used them on the Roadster (which weighed only 2050 lbs.) with th 205-50-15 in front. Trouble is that Tire Rack apparently does not have the smaller size (I have 4 used ones that may be available). And if you are going to use these tires in dry conditions, they should be shaved ($15 per tire).

Better yet, I would consider the following: Get some 16" rims (Beretta GTZ and maybe Grand-Am were equipped with 16x7); preferably ones that come in 16x7 and 16x8 (Rota Slipstream used to come in these sizes). Then run street tires. I would get the Hankook Z212 in 245-45-16 for the rear, and 215-45-16 for the front. You can get a full set of tires (shaved) from Frisby Tire (aka Sierra Tire) in Las Vegas for slightly more than $500 shipped. These tires should last an entire season.

Which group is getting your track day money?

------------------
FierOmar

quote Originally posted by FierOmar: Bernie: So, the engine is a stock V6? 4 speed trans? IMHO, I would want to do the following to make a decent track car: 1. Upgrade brakes to Beretta/Grand Am at the minimum; 2. Add the RCC bump steer kit; 3. Consider replacing shocks (KYB aren't too tough on the budget); 4. Replace all control arm bushings with poly; 5. Replace all cradle bushings with aluminum or at least with poly; 6. Stagger the front and rear tire sizes. 7. Don't forget a good 4 wheel alignment. As for tires, th 225-50-15 Kumho VictoRacer will work. We used them on the Roadster (which weighed only 2050 lbs.) with th 205-50-15 in front. Trouble is that Tire Rack apparently does not have the smaller size (I have 4 used ones that may be available). And if you are going to use these tires in dry conditions, they should be shaved ($15 per tire). Better yet, I would consider the following: Get some 16" rims (Beretta GTZ and maybe Grand-Am were equipped with 16x7); preferably ones that come in 16x7 and 16x8 (Rota Slipstream used to come in these sizes). Then run street tires. I would get the Hankook Z212 in 245-45-16 for the rear, and 215-45-16 for the front. You can get a full set of tires (shaved) from Frisby Tire (aka Sierra Tire) in Las Vegas for slightly more than $500 shipped. These tires should last an entire season. Which group is getting your track day money?

Yea, its a stock V6 - 4-speed............

Right now, it has the aluminum cradle bushings.
This would be a great time to look at brakes since mine are looking pretty shoddy right now. One of the rear pads per side was left out
as I was working on the car and the pistons have spun out to their limit..............can't get them to screw back in? They don't look like they
would be seized or anything..........any ideas?

Should do the bushings since I need to get an alignment done anyway after I put in the sport springs.
Shocks will have to wait for the time being as will the RCC kit..................only so much money.

Definately stagger the fronts and rears....

I'll gladly grab some used tires for the time being.
I can and will upgrade as time goes on but don't want to shovel too much into her until its been driven for awhile and I am
confident that I want to keep using it.

As far as track clubs are concerned, I don't have a new car one yet.
The guys I used to run with "Open Track Racing" appear to not exist anymore.
I'm open to suggestions?

Been doing all bike stuff for the last couple of years with an org called The Track Club
A guy named Mark Duncan. I became one of his control riders a few months ago so I
do my job and the day is a freebie. Means that I can add some car time now....woot!
Couldn't do both before.

Lemme know if you can set me up with some booties.....

Cheers
Bernie

quote Originally posted by Bernie: This would be a great time to look at brakes since mine are looking pretty shoddy right now. One of the rear pads per side was left out as I was working on the car and the pistons have spun out to their limit..............can't get them to screw back in? They don't look like they would be seized or anything..........any ideas? Should do the bushings since I need to get an alignment done anyway after I put in the sport springs. Shocks will have to wait for the time being as will the RCC kit. I'll gladly grab some used tires for the time being. I can and will upgrade as time goes on but don't want to shovel too much into her until its been driven for awhile and I am onfident that I want to keep using it. As far as track clubs are concerned, I don't have a new car one yet. The guys I used to run with "Open Track Racing" appear to not exist anymore. I'm open to suggestions? Lemme know if you can set me up with some booties.....

Well... for track clubs, Touring Car Club offers some pretty good deals for Saturday, Sunday or both days. Their next event is on Dec. 8 and 9 at Willow Springs. See: http://touringcarclub.net/events/schedule.aspx

Open Track Racing is still in business. Their next event is on Nov. 14, 2007, a Wednesday. See: http://www.opentrackracing.com/

I do have four Victoracer tires in the 205-50-15 size, but I would have to check to see if there are any 225-50-15 tires in storage.

As for brakes, I probably have a couple rear calipers lying around that I won't be using. I can't imagins someone failing to put the pad in. It's got to be a little hard on the caliper piston and the rotor.

There is a one-half price sale on Thanksgiving weekend at Pick-A-Part in Sun Valley, just north of Burbank. Might be a good time to pick up some calipers and rotors for the Beretta/Grand-Am upgrade. Parting off your rotors to make a hub is relatively easy for anyone with a lathe.

The RCC bump steer kit is about $120 and the poly bushings a little bit less. You can get KYB shocks for $184 for a full set.

Which springs did you end up getting?

------------------
FierOmar

Thanx for the info,

I guess OTR is having trouble with their site?
Sometimes it works and sometimes it doesn't. I used to get trackday notices from them all of the time but
haven't in a long time. Nice to know they are still in business.

It would be nice to get out in December but I will have to see how it fits my schedule. I am riding my trackbike up at
Laguna Seca in December as well.

I was the one who left the pads off the calipers. Since i was working on the car, I left them off for convenience as I was
only hanging the calipers temporarily. I guess one of my sons must have pressed the pedal and pushed the pistons out?

Can't remember what springs I used now? They were a gift and I didn't really pay attention to the make?

Would love to hook up and get tires off of you if you can cut me a decent deal?
Would also like to check out the brake options. Thanx for the pricing on the parts too!
You can email me at b2nomad/at/sbcglobal.net

Cheers
Bernie

[This message has been edited by Bernie (edited 11-05-2007).]

Are you wanting Street Legal tires or really race/track only tires? Dry or Wets? Soft or Hard?

John Stricker

quote Originally posted by Bernie: Plenty, Willow Springs is what consumed the last engine in my Fiero! I am also a control rider for a motorcycle track club running a Kawasaki ZX-7R racebike. Why do you ask? Cheers Bernie

quote Originally posted by jstricker: Are you wanting Street Legal tires or really race/track only tires? Dry or Wets? Soft or Hard? John Stricker

In another thread, on the topic of the Fiero Store Koni suspension kit, John wrote:

"We mixed and matched a LOT of parts and pieces on our race car before we hit on the system we felt most comfortable with. Keep in mind this is a RACE ONLY car.

We used an aftermarket sway bar, about 1.125" in diameter, in the front with a front bar in the rear. We also run Koni adjustable struts and shocks front and rear. We use stock height, WS6 springs.

If I were going to do it over again, and I am, I'd get a set of Hosler High Performance sway bars front and rear for their adjustablility. I'd also convert the rear Koni struts to coil overs and cut one full coil off of the front springs. Keep in mind that when you cut a spring, you increase the spring rate as well as shorten it. I plan to start with 425# springs in the rear and have extra sets on hand until tuning is complete (at least 3 more sets, 375#, 400#, and 450#. I'm fairly sure 425# is strong enough, probably too strong, but we'll see)

Paul's bars will cost you $640 for both front and rear.
You can do your own rear coil overs for less than $100.
Koni shocks and struts from the Fiero Store are about $560.

Total it up and you're at about $1,400 for a coil over setup far superior to what the Fiero Store offers. (BTW, The FS Racing kit includes new front AND rear sway bars, but they're not adjustable like Paul's are)

John Stricker

PS: Unless you really want to go racing, KYB's are not a bad choice either, but you lose the adjustability on the rebound dampening. Even new, Monroe Sensatracs can be made to work well. A set of Paul's bars with a new set of KYB's or Monroe's, new suspension busings, and new ball joints and tie rod ends will but your Fiero back on rails. Really."

John:

I pretty much agree with your comments except I'm not real excited about cutting the springs. We have done it in the past (both front and rear), and once cut, they don't fit the seat as well even after heating the top coil and repositioning it. It was more of a problem in the rear due to the way the original springs are made. Seemed to work o.k. though. Nevertheless, given the availability of new springs at virtually any size and spring rate desired at a relatively modest price, I will likely go that route in the future.

I am saving for a set on Paul's bars, but for a track car (not full race) like Bernie is putting together, it would seem that his funds would be better spent on some other things first.

Since he is looking at using a street car for the track, I recommended that he use shaved Hankook Z212 tires. They should work well enough; are much less expensive than slicks or DOT race tires like the Victoracer or RA-1 Toyos.

Couple other questions: Did you add a bump steer kit? Did you calculate the actual spring rate on the cut springs? What are your thoughts on the brake improvements I suggested to Bernie?

------------------
FierOmar

quote Originally posted by jstricker: Are you wanting Street Legal tires or really race/track only tires? Dry or Wets? Soft or Hard? John Stricker

Hi John,

I can go either way but the car is probably going to be transformed into a track only car. I have gutted all of the
emissions equipment and I am putting in straight through pipes on the exhaust. Doubt it will ever make it through
smog that way.

Definately will be going dry for now. Not much wet weather driving to worry about here in Socal. I will add another
set of rims later to hold a set of rain tires.

Compounds are open since I am not sure which track(s) I will be running on. I really like Buttonwillow on bikes
and it would probably be a great track for the Fiero. The big track at Willow is a lot of fun but it takes its toll on the
motor. Since my suspension mods are minimal at the moment, maybe a softer compound until I get more mods
dialed in and my speed goes up.

Cheers
Bernie

Order a set of Diamond racing wheels, steel will cost you about $160, then find USED road race tires. 23 X 9 - 15. The reason you need the wheels is they need a custom offset to clear the sidewalls on the suspension. We autocross on them all the time, you won't believe how sticky they are and will last track days and autocrossers a quite a while. They will NOT fit inside your fender openings but require no suspension modifications.

John Stricker

Edited because I know you're going to ask.........

If you want to run Cantilever tires, like 23 X 9 - 15, the backspace can be no more than 5" on a 15x8 wheel.
You can also use used Formula or Pro Atlantic tires, like 22.5 X 9.5 - 15 or 290/590R15 Radial Slicks with 5.5" backspace on a 15 X 10 wheel. I run the 23 X 9 - 15's myself. Greg Duncan says that if you want to do a little grinding on the upright, you can run 6" backspacing on the Formula Atlantic tires.

quote Originally posted by Bernie: Hi John, I can go either way but the car is probably going to be transformed into a track only car. I have gutted all of the emissions equipment and I am putting in straight through pipes on the exhaust. Doubt it will ever make it through smog that way. Definately will be going dry for now. Not much wet weather driving to worry about here in Socal. I will add another set of rims later to hold a set of rain tires. Compounds are open since I am not sure which track(s) I will be running on. I really like Buttonwillow on bikes and it would probably be a great track for the Fiero. The big track at Willow is a lot of fun but it takes its toll on the motor. Since my suspension mods are minimal at the moment, maybe a softer compound until I get more mods dialed in and my speed goes up. Cheers Bernie

[This message has been edited by jstricker (edited 11-06-2007).]

Thats great John thanx.

Do you have any sizing info to suggest?
Should I stick with 15's and should I offset the wheel size front vs. rear?

Cheers
Bernie

quote Originally posted by Bernie: Hi John, I can go either way but the car is probably going to be transformed into a track only car. I have gutted all of the emissions equipment and I am putting in straight through pipes on the exhaust. Cheers Bernie

The straight pipes might not give you the punch you are looking for. If pipes end up 6' long you get less hp due to pulses conflicting.

If you want straight pipes, you want to do headers into a collector before it exits into the pipes. You might want to look into exhaust design if you are intent on making the car the best it can be on the track. Just an FYI

Arn

quote Originally posted by FierOmar: John: I pretty much agree with your comments except I'm not real excited about cutting the springs. We have done it in the past (both front and rear), and once cut, they don't fit the seat as well even after heating the top coil and repositioning it. It was more of a problem in the rear due to the way the original springs are made. Seemed to work o.k. though. Nevertheless, given the availability of new springs at virtually any size and spring rate desired at a relatively modest price, I will likely go that route in the future. I am saving for a set on Paul's bars, but for a track car (not full race) like Bernie is putting together, it would seem that his funds would be better spent on some other things first. Since he is looking at using a street car for the track, I recommended that he use shaved Hankook Z212 tires. They should work well enough; are much less expensive than slicks or DOT race tires like the Victoracer or RA-1 Toyos. Couple other questions: Did you add a bump steer kit? Did you calculate the actual spring rate on the cut springs? What are your thoughts on the brake improvements I suggested to Bernie?

Intersting. I've had no problems cutting springs. I followed the instructions from a website detailing Herb Adams suspension suggestions for the Fiero. The only change I make is after I cut and smash, I then it them on a bench and hold them perpendicular, mark the bottom coil, and with a heavy hand grinder (4" would be SLOW) I grind the bottom coil as flat as I can make it. Never had a problem seating doing this.

No, I've never actually calculated the rates. Yes, I have two bump steer kits, one the RCC that's been modified, a second on the race car that's my own design. If you use the RCC kit, I'd definitely recommend some modifications. Will and I have had a discussion about this on the forum a couple of times. The one of my own design has yet to be driven (since it's is currently engine-less). I plan to make a coil spring tester this winter and I'm going to get some real life numbers for several sets of Fiero Springs both before, and after, cutting. I don't cut the rear springs, coil overs are just too easy to make and install back there and then your spring sources are limitless. You are limited in the fronts because they are a bit of an odd size. Coil overs would be better there too (with double adjustable shocks) but a LOT more difficult to implement. For now, I'm going to work on just cut springs and try some spring rubbers in the tester to fine tune the rate (if I can find some rubbers that fit properly).

As far as the rest of your suggestions, no real arguments except I like MORE TIRE. You can buy used race tires if you know where to look for $25 each. Superb tire technology in the Formula and Pro Atlantic tires, if you want to go that extreme. If you find one you really like, then buy a set of new ones. They cost about $225 each.

Brakes, I have been running the Grand Am brakes on the race car. Good stopping, very hard pedal with the Blazer MC. Big complaint for me is those calipers are very, very heavy. I'm going with the LeBaron 11.25" brakes when it goes back together with Wilwood Aluminum Metric calipers. Not recommended for the street since the Wilwood's don't have the dust seals. I'm not sure of the weight difference in the cast iron Grand Am calipers or the Cast Iron late Metrics, but if I remember some time I'll grab a metric caliper when I'm at the parts store and throw it on the scale to compare. The cost is going to be the same for the Grand Am/LeBaron upgrades except for the mounting brackets (about $100 for a set of 4) and either will fit in a 15" wheel. My experience is the stock Fiero brakes are marginal for hard autocrossing and completely inadequate for track days. Others may have differing opinions.

I also don't stagger my front tire sizes simply because my car is under 2,000 pounds and fairly close to 50/50 weight distribution. My cross weight needs work and that's going to be addressed this winter as well. Or it was. It's probably going to gain some weight with the new motor and full cage. We'll see. I don't want to run much smaller of a tire in front regardless because of the push the Fiero has when under power. The more grip I have, the better I like it. Of course this works in reverse when NOT under power.

Get proficient at doing your own alignment. You're going to be tweaking and at least need to know how to properly set your toe. That's the hard one anyway, camber in the back is a piece of cake and when at the track you generally need all you can get out of the stock knuckles regardless. Just make both sides match. Again, not for the street, just for the track. But your note about the alignment and getting it right is spot on.

Definitely go poly in all the arms (or steel) and solid alumimum bushings in the cradle.

A couple of friends have been running Fuzion tires on the autocross track. Economical and good grip. Decent wear, but hard autocrossing is tough on any tire.

I'd say that we're not far off on our recommendations, mine vary based on the peculiarities of my specific car.

John Stricker

quote Originally posted by jstricker: Yes, I have two bump steer kits, one the RCC that's been modified, a second on the race car that's my own design. If you use the RCC kit, I'd definitely recommend some modifications. Will and I have had a discussion about this on the forum a couple of times.

O.K. I seem to recall that the concensus is to move the inner mount/pivot point as much outboard as possible. But, would you say that stock RCC kit is an improvement even if not the perfect solution?

quote Originally posted by jstricker: Brakes, I have been running the Grand Am brakes on the race car. Good stopping, very hard pedal with the Blazer MC. Big complaint for me is those calipers are very, very heavy. I'm going with the LeBaron 11.25" brakes when it goes back together with Wilwood Aluminum Metric calipers. Not recommended for the street since the Wilwood's don't have the dust seals. I'm not sure of the weight difference in the cast iron Grand Am calipers or the Cast Iron late Metrics, but if I remember some time I'll grab a metric caliper when I'm at the parts store and throw it on the scale to compare. The cost is going to be the same for the Grand Am/LeBaron upgrades except for the mounting brackets (about $100 for a set of 4) and either will fit in a 15" wheel. My experience is the stock Fiero brakes are marginal for hard autocrossing and completely inadequate for track days. Others may have differing opinions.

Lebaron rotors with Wilwood metric. XLNT! I had come to the same conclusion a long time ago. The Wilwood caliper is advertised as 2.97 lbs. Although I haven't weighed the GM caliper, I wouldn't doubt that it is at least double that amount. And, this is one brake package that can be run on all years; 84-88, since V8 Archie offers the Lebaron brackets for the 88. Of course those who install an 88 rear cradle can use this set up on all 4 corners. That is my plan, particularly since Paul is now offering his sway bars for the 88.

quote Originally posted by jstricker: I also don't stagger my front tire sizes simply because my car is under 2,000 pounds and fairly close to 50/50 weight distribution. My cross weight needs work and that's going to be addressed this winter as well. Or it was. It's probably going to gain some weight with the new motor and full cage. We'll see. I don't want to run much smaller of a tire in front regardless because of the push the Fiero has when under power. The more grip I have, the better I like it. Of course this works in reverse when NOT under power.

Which engine are you running? Our roadster with stock V6 and 4 speed weighed in at 2050 lbs. It did have a roll bar, but not a cage. What were your corner weights?

If I recall corredtly, it was Will that explained the "center of traction" concept as part of his explanation of why staggered width tires should be used on the Fiero.
Even the Lotus Elise at 1985 lbs. uses staggered tire sizes.

As for relatively simple front height adjustable coil spring, Gerald Storvik had developed a mount coilover mount for the front of his AutoX car. See: http://www.8shark.com/33.htm It is pictured in the 4th and 5th photos down the page. Not really a coil over, but should allow for herght adjustment which might help when attempting to adjust corner weights.

------------------
FierOmar

Guess who has a friend that works at Wilwood?

Anyone got a PN for the calipers in question?

Cheers
Bernie

120-6426, 2 each right hand and left hand (front and rear). They use the same P/N but you need to designate RH or LH for Bleeder Orientation.

230-0619 Slide Pin Kit is also required for mounting. It shows them as a "4 Pack" which I presume means there is enough in one to do two calipers. If so I need two of the kits, but enough to do 4 calipers.

John Stricker

quote Originally posted by Bernie: Guess who has a friend that works at Wilwood? Anyone got a PN for the calipers in question? Cheers Bernie

I get my tires from http://www.jbracingtires.net/
Usually $70 each for full Hoosier / Goodyear slicks with one use on them.

Tell him Chuck from Orlando sent you. He'll help you get the right tire too. I had no idea what tire I wanted at first but he asked a few questions and helped on the decision. He is very knowledgable and an all around nice guy too.

Thanx for all the info fellas,

I have the Wilwood catalogue and have found the GM Metric calipers.
PN _ 120-6426 - calipers 2 left and 2 right.
PN _ 230-0619 - slide pin kit (says its a 4 pack so I assume 2 packs necessary)

They have a pretty decent catalogue of parts.
Think I can get the rotors out of here as well?

They also have braided lines, pedals...............yeesh!

Spoke to Diamond wheels - Bill to be exact.
The PN for the black wheel is 15080-08-57-050-6-00 (Price is 79.75 each)
The lug nuts are about a 1.65 a piece.
Nice folks!

John, are you saying that I have to cut the fenders for the wheels to fit?
I don't have a problem with it but I just wanted to be sure?

Cheers
Bernie

[This message has been edited by Bernie (edited 11-07-2007).]

A member of Golden Gate Fieros (GGF) (based out of Redwood City, CA) is a racing instructor for a track day group. He races Fieros on track days (on stock rims) He'd probably be a good point of contact. I suggest getting in touch with GGF and asking them to forward your contact info to him.

I think there is another track day coming up Nov. 17th ask him about it too if you're interested. Mention Max sent ya.

Brian Geyer?



John Stricker

quote Originally posted by Austrian Import: A member of Golden Gate Fieros (GGF) (based out of Redwood City, CA) is a racing instructor for a track day group. He races Fieros on track days (on stock rims) He'd probably be a good point of contact. I suggest getting in touch with GGF and asking them to forward your contact info to him. I think there is another track day coming up Nov. 17th ask him about it too if you're interested. Mention Max sent ya.

Hey Guys,

I spoke to my contact at Wilwood and he is going to set me up with the calipers and slide pins.
He had a question:
He wants to know if I want to offset the bores between fronts and rears? Apparently, I can run
bigger piston bores on the front vs. rears to help with the front to rear brake balance. Have you guys
thought about or done this?

Going to call him tomorrow and maybe even drive over there to see the factory. They are located
in Camarillo which is only about a 30 minute drive for me.

Bernie

The catalog shows the ALUMINUM calipers available in only one bore size, 2.38". The iron caliper they offer is available in 2.00" and 2.75" bores. Neither of these have dust seals that you should have on the street. If this is strictly a race car, then they're really not necessary.

Having said that, if he says the ALUMINUM calipers are available in different bore sizes, before one could make a decision you'd have to know what size. In the iron calipers, 5.94 sq in for the 2.75" bore and 3.14 sq in for the 2" bore, that's 52% more brake in the front than the rear. That's a whole heck of a lot of front brake bias out of the box.

My inclination would be to keep things square and use a proportioning valve.

John Stricker

PS: What kind of price did he give you???? Don't forget, you need a Left and a Right for each end of the car, or you'll end up with the bleeder on the wrong side and have a hard time bleeding the brakes.

quote Originally posted by Bernie: Hey Guys, I spoke to my contact at Wilwood and he is going to set me up with the calipers and slide pins. He had a question: He wants to know if I want to offset the bores between fronts and rears? Apparently, I can run bigger piston bores on the front vs. rears to help with the front to rear brake balance. Have you guys thought about or done this? Going to call him tomorrow and maybe even drive over there to see the factory. They are located in Camarillo which is only about a 30 minute drive for me. Bernie

Yea,
I guess sticking with one caliper and biasing it with a proportioning valve is a safer bet?
He says that they don't designate right and left anymore. There is one caliper and there
are 2 bleed holes. The bleed screws come in a baggy. You put the bleed screw on whichever
side that you want and then there is a screw plug that fills in the unused side.

Don't have pricing yet, calling him before noon today.

Couple of questions:
Should I start searching for a Blazer MC now?
What to do with the parking brake? Do I just strip it all off?
What about brake lines? They have their own but how do I interface these new calipers to my existing hard lines?

Cheers
Bernie

quote Originally posted by jstricker: My inclination would be to keep things square and use a proportioning valve.

I concur. Depending on the engine being used, the Fiero has a weight bias of approximately 43% front and 57% rear. (Moving the standard size battery to the front will alter this balance by 1% point) This is what I refer to as static weight, that is while the car is at a stop.

I have read that under hard braking, the forward inertia will shift the weight as much as 17% towards the front... probably a little less for a well prepared track car... so lets use 15% weight transfer. Assuming these numbers are correct, under hard braking the Fiero would have a front bias of 58% to to 43% on the rear. There is a similar shift under hard acceleration, but that is a good thing for the RWD cars (sort of explains why those pesky VW's can launch so well at the drags).

Even the "ideal" car with 50-50 static weight would have a front bias of 65% front and 35% rear under hard braking. Some front wheel drive cars will have closer to 80% front bias under heavy braking. In any event, when braking is considered, the best set up will have a slight rearward bias. It might surprise you to learn that the front engine/rear drive Factory Five Racer is closer to 45% front and 55% rear bias, almost identical to he Fiero. The Lotus Elise is approximately 39% front and 61% rear. FWIW, the Elise uses staggared tire sizes... the FFR doesn't.

Thus, while using smaller caliper pistons might make sense on a FWD car, or perhaps even some front engine/RWD cars, in order to minimize rear brake lock-up, I would think it would not be needed on the Fiero. A simple proportioning valve would likely be better. Wilwood sells them. Be sure to tell the Wilwood rep what your planned use is.

One other thing: I would not invest in the Willwood calipers unless I were going to upgrade the rotors. A final note: I have just assumed that Wilwood's GM metric calipers would be available for the Lebaron brake upgrade only. Check to see if they could be used in place of the Beretta (or Grand Am) calipers.


------------------
FierOmar

[This message has been edited by FierOmar (edited 11-08-2007).]

quote Originally posted by FierOmar: [QUOTE]Originally posted by jstricker: My inclination would be to keep things square and use a proportioning valve.

One other thing: I would not invest in the Willwood calipers unless I were going to upgrade the rotors. A final note: I have just assumed that Wilwood's GM metric calipers would be available for the Lebaron brake upgrade only. Check to see if they could be used in place of the Beretta (or Grand Am) calipers.

[/QUOTE]

He said that they could come up with a top-hat / rotor combination to work on the car BUT he also stated that it would probably
be better to use a stock rotor (I am assuming the Lebaron 11.25"?). He claims the one-piece stock rotor will dissipate more heat
as it is a bigger "heatsink" than the 2-piece designs that they have. He is quite clear on what I am doing with the car and I am
sure he will set me up with the right bits. I will also get the proportioning valve from them.

Cheers
Bernie

quote Originally posted by FierOmar: One other thing: I would not invest in the Willwood calipers unless I were going to upgrade the rotors. A final note: I have just assumed that Wilwood's GM metric calipers would be available for the Lebaron brake upgrade only. Check to see if they could be used in place of the Beretta (or Grand Am) calipers.

To use the GM Metric calipers you have to have new caliper mounting brackets made/installed. The Grand Am caliper mounting ears are the exact same distance apart as the stock Fiero, right at 5.8" on center. The GM Metric's are 5.46" on center so they are not directly interchangable.

John Stricker

quote Originally posted by jstricker: Brian Geyer? John Stricker

Yep. He's not online much, so I figured nobody knows him by name.

Hey John,

I want to be certain that I am looking for the right rim size as per your tire suggestions.
Please help me clarify:

15 x 8 wheels (all 4 corners)
5 x 100mm bolt pattern (obtained from another forum posting) (what is the NA equivalent)
12mm x 1.5 lug (obtained from another forum posting)
57. 1 center bore (obtained from another forum posting)

Given the choice, what backspacing should I be looking for?

Cheers
Bernie

Bernie,

I'll have to post a picture of the race car. I don't have my fenders cut, yet, because the ride height on it is stock and the wheel/tire combination is short enough there is quite a bit of clearance especially with high rate competition springs.

As noted in my earlier post, a 5" backspace with the 23X9-15 tires will give you clearance with the upright and the original springs. Coilovers are not required (although I suggest them so you can adjust your ride height and cross weight, but you don't need them for clearance).

The folks at Diamond are nice to deal with, but S L O W. Really slow. At least in my case. Whatever you do, never tell them you're in no hurry. Tell them you need them yesterday.

I'm going to be lowering my car and may have to cut the fenders, I don't know yet. I'll have to see what things look like when it's done with the coil overs in place.

There really isn't any "american" substitue for the 5X100 bolt pattern. 100mm=3.937", so it's not even really a 4" pattern. Diamond has 5X100 centers so that's not a problem.

The lug nuts Diamond sells are very large head, I think 7/8" if memory serves, and you might want to get a few spares just in case one gets kicked in the paddock.

Unless my memory is getting worse, the rest of your dimensions are correct.

John Stricker

quote Originally posted by Bernie: Thanx for all the info fellas, I have the Wilwood catalogue and have found the GM Metric calipers. PN _ 120-6426 - calipers 2 left and 2 right. PN _ 230-0619 - slide pin kit (says its a 4 pack so I assume 2 packs necessary) They have a pretty decent catalogue of parts. Think I can get the rotors out of here as well? They also have braided lines, pedals...............yeesh! Spoke to Diamond wheels - Bill to be exact. The PN for the black wheel is 15080-08-57-050-6-00 (Price is 79.75 each) The lug nuts are about a 1.65 a piece. Nice folks! John, are you saying that I have to cut the fenders for the wheels to fit? I don't have a problem with it but I just wanted to be sure? Cheers Bernie

Looks great John,

The reasom I was asking was because I stumbled upon Aero Racing Wheels today and they are having a clearance
on a lot of their wheels. Some as low as 30.00 a piece!
Unfortunately, they don't list a 5 x 100mm bolt pattern anywhere on their site so its probably nothing.

Do you guys already have an adapter plate in mind for bolting up the Wilwood calipers?
My friend is going to bring one by for me so that I can figure things out with it.

Cheers
Bernie

You can order them in this thread
https://www.fiero.nl/forum/Forum4/HTML/035259.html

But read through this thread first
https://www.fiero.nl/forum/Forum1/HTML/048271.html

(If you haven't already)

John Stricker

quote Originally posted by Bernie: Looks great John, The reasom I was asking was because I stumbled upon Aero Racing Wheels today and they are having a clearance on a lot of their wheels. Some as low as 30.00 a piece! Unfortunately, they don't list a 5 x 100mm bolt pattern anywhere on their site so its probably nothing. Do you guys already have an adapter plate in mind for bolting up the Wilwood calipers? My friend is going to bring one by for me so that I can figure things out with it. Cheers Bernie