Shelby Cal 500 Wheels

[PNWSmoker]

Anyone have any of these? I bought the below wheels with some junk tires on them the other night. They came off a 1974 Fiat and I have a 1978. The pattern seems correct but whem the lug bolts get down past the threads they are extremly tight and the lug bolt seems to shave the wheel. Anyone know what's up here?

Thanks.

[velozi]

Fiat uses a 4x98 wheel bolt pattern. This is an extremely difficult pattern to find.

Maybe those wheels are 4x100 which is close but will eventually fail.

[PNWSmoker]

Fiat uses a 4x98 wheel bolt pattern. This is an extremely difficult pattern to find.

Maybe those wheels are 4x100 which is close but will eventually fail.

They came off a 1974 Fiat though. I saw the car when I bought them... 74 and 78 patterns are the same correct?

Anyone use a adapter to go to 4 x 100? I saw them on them on http://adaptitusa.com/

[kmac33]

All Spiders have the 4X98 bolt pattern. There are a number of folks here on the forum that have used the adapters to go with a 4X100 wheel which is much more common.

[PNWSmoker]

All Spiders have the 4X98 bolt pattern. There are a number of folks here on the forum that have used the adapters to go with a 4X100 wheel which is much more common.

So no worries with the offset from the spacer?

[Curly]

I have a similar set of wheels on my AC coupe, and found that occasionally a burr develops under the wheel nut washer which makes removing the wheel bolts or sleeved nuts difficult. I've used a countersinkng drill bit to flare the wheel nut holes slightly under the flat washer which stops the burr from forming.

[kmead]

I have the same wheels on my Coupe as well and they are somewhat difficult to mount up. I would clean any oxidation out of the holes and clean the bolts (the cylindrical part that contacts the hole in the wheel). A little anti seize on the bolt will do wonders as well. Be sure to torque them down properly, these rims are not hub centric so they rely only on the bolts.

[kmead]

.

[PNWSmoker]

I have the same wheels on my Coupe as well and they are somewhat difficult to mount up. I would clean any oxidation out of the holes and clean the bolts (the cylindrical part that contacts the hole in the wheel). A little anti seize on the bolt will do wonders as well. Be sure to torque them down properly, these rims are not hub centric so they rely only on the bolts.

They still fit freaking tight. Like so tight I'm afraid I might break a stud off with the rattle gun. I'm going to take them to the tire shop and have them measure the pattern.

Is 4x100 close enough to 4x98 that you could possibly force it on? Could that be the deal here? I don't want to do this I'm just asking for my own knowledge.

Thanks

[kmead]

Is 4x100 close enough to 4x98 that you could possibly force it on? Could that be the deal here? I don't want to do this I'm just asking for my own knowledge.

Thanks

No you wouldn't be able to get them all started.

Take some calipers, measure from the outside of hole to the outside of two opposing holes, write it down. Measure the distance from inside of two opposing holes, write it down. Add the two numbers together, divide by two and you will have the bolt center diameter from bolt to bolt.

With the rim off the car, how tight are the bolts into the openings in the rim?

[PNWSmoker]

Is 4x100 close enough to 4x98 that you could possibly force it on? Could that be the deal here? I don't want to do this I'm just asking for my own knowledge.

Thanks

With the rim off the car, how tight are the bolts into the openings in the rim?

They seem to fit fine off the car. It's just when I put them on the rattle gun has a hard time knocking them all the way down. I'll snap some close ups of the holes to show how they are chewed up a bit.

Maybe the lug bolts are just a bit too big?

[kmead]

I would definitely measure the hole center diameter, it sounds like they are not the right size.

I presume you have run the bolts into the holes without the rims to verify they are the right thread?

I also would not use an impact wrench to run them in regardless.

[PNWSmoker]

I would definitely measure the hole center diameter, it sounds like they are not the right size.

I presume you have run the bolts into the holes without the rims to verify they are the right thread?

I also would not use an impact wrench to run them in regardless.

Measured them last night and they are 4 x 98. I gave it another go mounting them and they do mount up but are very tight. My neighbor is a mechanic and he said they should be fine but it just seems weird that they are so tight.

The neighbor says "it's a Fiat what do you expect". I'll snap some pictures once I have the new tires mounted and all the wheels on.

[azygoustoyou]

You could use the impact wrench on your neighbor though!!

[PNWSmoker]

You could use the impact wrench on your neighbor though!!

He's a Chevy guy which I am too so it's all good. He's got a bad ass Drag Nova he runs at a strip close to us.