Hey all I have a wheel question. I was given today a set of borbet Type A wheels 17x7.5 5x114 lug and et30 Offset.. I know i need adaptors but i dont know how big or small to go its going on a 85 GT any help will be great

The problem is that the stock 15x7 wheel has a 30mm offset and is almost 3/4" inside the wheel well. Your wheel as it sits at 7.5 wide would be just about level with the lip of the fender wells. You can try a 1" adapter but you might be extending the wheel slightly past the fender lip.

Not sure how this helps but I was using 18x8 with a 38mm offset, up front it was slightly past the fender but looked good, in the rear I used 1" adaptors and it was even with the rear fender.

I've got 2003 Bonneville 17x8 wheels (5x115mm) on my 87 Fiero coupe with 20mm thick wheel adapters. The rear tires stick out just about flush with the tops of the rear fenders.

But the front tires rub on the inner wheel well liners when you turn the wheels almost all the way to one side or the other - the reason being that the 20mm thick wheel adapters increase the radius of the tire's turning circle in relation to the ball joint centerline. If I could eliminate the 20mm thick wheel adapters, I am confident I would have no tire to inner wheel well liner rub on turns.

The problem is the stock 84-87 Fiero front spindles and finding a different hub that will work on it that has the 5x115mm wheel bolt pattern. I thought I had found a workable solution by using 99 Mustang front wheel hub bearings, but that turned into a no-go because the Fiero spindle and nut could not be torqued to the spec the hub bearing requires.

I'm still looking into other options. Perhaps I should just fabricate a new spindle assembly out of chromoly steel tubing and design it so it would accept a hub bearing from virtually any other OE application I see fit. This would certainly open up upgraded brake options...

-ryan

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quote Originally posted by Darth Fiero: I'm still looking into other options. -ryan

Couldnt just run a smaller or lower profile tire in front? Is there a downside to that besides not being able to rotate tires?

[This message has been edited by 2.5 (edited 08-12-2014).]

quote Originally posted by 2.5: Couldnt just run a smaller or lower profile tire in front? Is there a downside to that besides not being able to rotate tires?

I could, but I drive my car on roads that aren't the best and I fear that running any lower of a profile tire could lead to rim damage from such roads.

That having been said, I have always had future suspension and brake upgrade plans for this car. I have a set of 2003 CTS dual piston brake calipers and brackets sitting here waiting for a new home (hopefully in my Fiero). But before I can install them, I need bigger rotors. And before I do that, I want to eliminate the wheel adapters and fix the steering/rubbing issue.

Like I said, the only thing holding me back right now is lack of a wheel hub that has a 5x115mm bolt pattern. If I could only find someone who could machine one that would accept the stock 84-87 Fiero front tapered roller bearings I would be in business. It is either that or replace the Fiero spindle with something that can accept a different hub bearing.

I just find it hard to believe after all these years, us Fiero guys are still stuck with 5x100mm hubs.

There are dozens and dozens of wheels that fit 5x100 bolt pattern. You have to be hard pressed to not be able to find something you like. Most times I see people wanting adapters are to make wheels they were given or bought dirt cheap fit. Those cheap wheels end up costing as much as buying new ones made to fit. If you do have your heart set on a different bolt pattern, making new hubs or spindles is the way to go though.

well I have adaptors coming tomorrow.. And i believe spending a few dollars to fit Borbet Type A flat cap wheels that i got for free is worth it

quote Originally posted by CTfieroGT: And i believe spending a few dollars to fit Borbet Type A flat cap wheels that i got for free is worth it

I'd like to see the wheels on your car. Post a picture or two here. Use PIP.

quote Originally posted by rogergarrison: There are dozens and dozens of wheels that fit 5x100 bolt pattern. You have to be hard pressed to not be able to find something you like. Most times I see people wanting adapters are to make wheels they were given or bought dirt cheap fit. Those cheap wheels end up costing as much as buying new ones made to fit. If you do have your heart set on a different bolt pattern, making new hubs or spindles is the way to go though.

I have not seen an aftermarket wheel I like on a Fiero, at least nothing that is already available in a 5x100 bolt pattern. Everything I like has a different bolt pattern and to get it custom made in a 5x100 will probably cost several hundred dollars per wheel.

That having been said, I really like the 2003 Bonneville SLE chromed aluminum 5-spoke 17x8 wheels I have mounted on it now with the wheel adapters. I got the wheels for $150 for the set of 4 and the adapters only set me back $280. Total combined cost = $430. I don't know where you think I'm going to be able to find a good looking and quality made set of 17x8 wheels with a 5x100 bolt pattern for even close to this much because I have looked.

The 5x100 bolt pattern hubs are going to be upgraded soon. I'm already running thru new Timken rear wheel hub bearings at a rate of about one every two years. I believe the problem is the small size of the hub bearing the amount of torque I'm putting thru them with this turbo engine. I don't care for the small diameter outer CV tripot axle spline size either, so this is something I want to upgrade anyway. I'm already looking at other GM knuckle options that will give me the bigger wheel bearing, bigger CV axle diameter, and bigger 5x115 bolt pattern (as well as being able to accommodate bigger brakes). I actually already have an aluminum knuckle sitting on the shelf I think I can make work for this job.

Anyway, the rear isn't the problem. The front is. I either need a custom hub (w/ 5x115 bolt pattern) that will work on a stock Fiero spindle or a custom made knuckle to replace the spindle assembly that will allow me to bolt the hub bearing of my choice onto it.

Down the road, I eventually want to try putting 4 wheel ABS on my car and the only way I'm going to be able to do that is if I have ABS wheel speed sensors at every corner. I can do that with off-the-shelf GM FWD wheel hub bearings that have the 5x115 bolt pattern.

[This message has been edited by Darth Fiero (edited 08-14-2014).]

These are 5x100 and fit a Fiero perfectly in the offset. I prefer silver painted wheels for low upkeep since I drive all my cars all year round in all weather. Polished alloy, chrome dont last a season here. Theyre from TireRack and cost $75 each with lugs and centers included. I also always prefer a 5 spoke style wheel.

quote Originally posted by rogergarrison:

Sorry, I think they're very plain looking and I don't care for them.

That having been said, I doubt those wheels you have pictured on your car are offered in a 17x8 size with a 5x100 wheel lug pattern for $75 each.

[This message has been edited by Darth Fiero (edited 08-14-2014).]