What tire and wheel combinations are some of you guys who went aftermarket running? I think I've been misinformed about Fieros not being able to run any tire and wheel combos. other than what came on it from the factory. I have an 88, so I would definatly like to hear what wheels and tires fit that year. I'm sure we all would like to see some pictures too.

I have the stock 6 inch wheels up front with 205/60/HR15 Yokohama A509 tires and stock 7 inch in back with 225/60/VR15 A509s. The back tires are a little taller than stock but they have less sidwall flex, being V speed rated, than the old Pirelli P600s I had on there. The tread pattern is wide and blocky. They are very good for autocrossing because they heat up fast.

I have 16s on mine, 225 50s on all four. With a 7 1/2 rim. And it looks good in i say so myself.

you can run anything you want as long as it meat 2 rules.

1. obviously, it can't be so big it contacts the wheel well. Not so obviuosly it mustn't hit the well in front when turning.

2. it must have close to the same rolling diameter as the stock wheel set. If it doesn't you'll trow off the ECM and speedometer. I think there are other gear sets to fix the sender if that happens, but figuring out just what one to use is a pain.

When Lotus got involved,in '88,didn't the GT get 6" front,and 7" rear rims,what were the original sizes?
My car handled very nuetral with only 195/65(uniroyal,BMW-oem,good) on front,205/60(A509,excellent)in rear all on 6 1/2X14 factory rims.
So,would the 16" equivalent be 225/50,and 205/55?

Yes, I believe the +2 sizing 16x6 thru 16x8 wheels with 205/55/16 and 225/50/16 would be a good upgrade. However, your rear tire diameter will change. If you want to check go to Dunlop's tire website. They show all tire diameters in the specs for various sizes. If that is, indeed, the case, you may want to consider a fifteen inch wheel tire package. The wheels will be cheaper and so will the tires. It would be a lot more economical than trying to find a lower profile 16 inch tire.

As far as the 88s are concerned, there was no need to continue using the 7 inch front rims with the new suspension. The older V6s used this wider front wheel tire to compensate for problems with the suspension. The original sizes for the 88s tires are 205/60/15 front, 215/60/15 rear.

My 85 GT has the stock 14 rims but with P215 rubber all around, the rubber is obviously wider then the rim but it doesn't contact anything. In the back end the closest part that would hit the rubber would be the strut coil ( mines about 1/4 - 1/2 inch away), so if you would use a coilover conversion kit, lets say from ryane motorsports then there would be alot more room cause that perticular kit uses 2.5" id springs. Supposedly you can put P245's and larger on if you use the right offseting. The kits runs about 2640 bucks.

Yeah,I guess the production racer's were beating the Porsche944s with the advantage of the 215 tire,think the cars were lacking adhesion in front though.
Dunlop,huh...Thanks,I'm into some more research.Not sure about the weight/ distrubution,but the new Lotus is using 185/55-15front,225/50-16rear.I know the extra sidewall helps in the front from my experience.Maybe I'll try 205/60-15front,and 225/50-16 rear.Hmmm.

Why would extra sidewall help in front. I always thought that the lower aspect ratio aids in improving steering response. The Dunlop site has all the tables for comparing tire sizes, dunloptire.com.

The "slip angle" of a taller tire is more forgiving(wider),since these cars tend to push at lower speeds,the effect is a good one.OK,slip angle is the amount of room a tire has to maintain effective grip as the car,or tire, is no longer pointing in the direction that the rest of the car is(sliding).Should be called"sliding angle".With better predictability of your steering,the easiier it'll be to keep the heavy end of the car following the line you've chosen into the corner.The early cars,with poor springs and lacking the adhesion,were worse,just used wide tires as a crutch.

The wider wheel base used on 88 fieros was the reason for using the thiner 6" wheels on front. I would not suggest running all the same width wheels on an 88 for this reason. (Lotus did not develop the suspension on ANY fiero, period). Some very good info on fiero wheels can be found here:

http://members.xoom.com/fierov6/OSG/wheels.html

My 4-cylinder 87 car wears the same size tires as LowCG's car. When I bought my V8 Fiero, it had 245/60 tires on the rear and 235/60 tires on the front. On the inside of one of the rear tires, it had faint signs of rubbing. I put the 235/60's (Goodyear Eagles) on the rear and they work great. I put some old used 215/60's on the front for now. I'd like to bring the front of the car down a little lower, can anyone recommend a real low profile radial tire (and/or size) I can use?

The 245/60-15's are one of the more popular tires run on the rear of 86-88's. I have never heard of anyone having rubbing problems with them on stock fiero's. I suspect that it may be the additional weight of the V8 overcoming the suspension on bumps, squat, etc. Perhaps a stiffer spring on back would help this? I found a nice little site for quick tire size / speedometer error comparisons of different size tires:

http://www.miata.net/garage/tirecalc.html

I think that lowering the front would be MUCH better than a smaller diameter tire, since that may result in some handling/cornering problems, but straight line performance could improve somewhat.
I have actually considered some 275/50-15's on the back of my formula (dont laugh) :-) They have nearly the same diameter as the 225/60-15's I am using on the front. If I could only get them suckers on my 7" rims I would.. (but, thats the point when I usually wake up, and pour the ol' morning coffee) :-(

Actually, I forgot to mention that I'm running 14 inch rims on both my Fieros, just in case that makes a difference. I might just compromise and put a pair of 205/60 tires on the front. That's about an inch smaller than before. By the way, heavier springs were installed in the back when the V8 went in.

I'm not familiar with the more unique properties of a V8 car,however,the 205/60 does fit well on a stock-sized rim,better than the 215/60.One size that isn't too common,was oem on some VWs,that's a 195/55 14,like a squatter version of 205/60.Might be cool;the much smaller Dia.would probably make the goemetry funky though.
Maybe you should check out some tech suspension parts(ie.springs,bilsteins)for that V8 car,if you need to keep the nose down/in control.I've got a tested,bargain-basement recipe...

I think you may be right, LowCG. I need to change the worn out control arm bushings and put in some new poly bushings anyway, so I should change the front springs at the same time. I like to drop the front nose down at least another inch. Any recommendations?

This is a fun one,because you're not committed to using any components,or"kits".
To start with,I'd get some lowering springs(I used Tokico) from the front of a Rabbit/Scirocco,then,make a spacer out of a piece of thickwall tubing with a flange welded to the end where the spring will seat(totall length is 2 5/8" I believe,will have to check notes at secret lab to confirm).A decent muffler shop can weld this kind of thing,once you cut the pieces.Put the urethane lower control arm bushings in when it's apart.
This will bring the nose as low as you can go and not ruin the suspension's ability to function(lower control arms paralel to ground).You could gain another 5/8" by using Caddy('71-'82,Fleetwood)upper balljoints,welded onto lower fiero control arms,huge joints,probably last forever,reduces bumpsteer also.
The last bit of screwing around would be to shorten the links that connect the swaybar,keeping the swaybar horizontal,or directly acted upon,I used some all-thread,and steel tubing,nylock hardware.Then remount using urethane in the inner mounts,modified urethane(so as not to bind AT ALL;little,cone shaped)on the outer swaybar.Sander works good for this.
As good a shock as you can afford; I used Volvo P1800 Bilsteins.
If you do all this crap,gradually,starting with the most buried/involved,then swaybar mods,good shocks,I guarantee you'll be grinning hard after even the first stage.

I'm running a 1987 GT with the Diamond Spoke 15" wheels. I'm thinking I'd like to move to 16" wheels on the rear. Did GM ever put out a 16" version of this wheel on any other GM product? If so, would it fit the Fiero bolt pattern?

I do believe that is has been established that Lotus did not have anything to do with the suspention redesign of the '88 Fiero- some- more of this urban legend stuff.

Lots of 16" rims will fit the Fiero. Try the 16"er from a Beretta GTZ or Z26. They look cool. Pretty much any rim will work as long as the bolt pattern (5 x 100mm), the offset (34-37mm), and the circumference are correct. I suppose you could put 20" rims on if the above conditions were met. (Just don't complain about the price of tires:-))
BTW--'87s (at least GTs) had the different width rims, too.

I have an 86 GT, and I have 215/60/15 on the front and 225/60/15 on the rear, BFG Comp T/A's. My rims are identical width front and back (15X7). With the stock springs, nothing rubs, but with the Suspension Techniques springs the fronts rub the inner fender panel at full lock.

The beretta gtz wheels fit well but on the rear the offset is different. To restore handling the wheels need to be spaced out another half inch which entails new studs to accomodate a spacer. For safety this should be done by a professional as I sure don't want suspention of steering probs at 120 mph on tight corner. The gtz wheels come in a variety of colors and look as if they were made for the Fiero and with 225/50-16 in back and 215/50-16 in front the handling is tighter and although breakaways happen quick they are consistant and controlable. Rear camber is extemely sensitive with wide low profile tires, watch treadwear and use the same mechanic every time until the handling is dialed in perfect.

I just tried to put my brother-in-laws 15" rims (from a '90 Beretta GT) on my car. I got one on the back, but it seems to be too wide. I has the same size tires, but it won't even go on the hub tight. That's how bad it rubs. Any idea how much new studs and a spacer would cost? I could go with different wheels, but these are in pretty good shape and they're free. These are the same style as the GT rims.