According to this ebay ad the bolt pattern is different for a Gallardo:
http://cgi.ebay.com/ebaymotors/ws/eB...7752&rd=1&rd=1

Good Wheel Info:
Plus Sizing

Plus sizing your wheels and tires is the best way to improve both the performance and appearance of your vehicle. By using a larger diameter wheel with a lower profile tire it's possible to properly maintain the overall diameter of the tire, keeping odometer and speedometer changes negligible. By using a tire with a shorter sidewall, you gain quickness in steering response and better lateral stability. The visual appeal is obvious, most wheels look better than the sidewall of the tire, so the more wheel and less sidewall there is, the better it looks. Please contact our sales team for assistance in the proper sizing for your vehicle.

Plus sizing your wheel & tire combination was designed to enhance vehicle performance and looks by allowing fitment of larger diameter rims and lower profile tires. The theory is that while making these changes, you keep the overall tire diameter within 3% of the original equipment tires. This is important because larger variances can cause problems with transmission shift points which can decrease fuel mileage. It can also confuse braking system computers which can even lead to brake failure.

Here's the rule of thumb for "plus sizing":

Plus 1:
Increase section width by 10mm
Decrease aspect ratio by 10 points
Increase rim diameter by 1 inch

Plus 2:
Increase section width by 20mm
Decrease aspect ratio by 20 points
Increase rim diameter by 2 inches.

This is not exact, but it will usually get you in the right ballpark. We always recommend consulting with the people you are purchasing the wheels and tires from to ensure fitment.

Offset

The offset of a wheel is the distance from the mounting surface of the wheel to the true centerline of the rim. A positive offset means the mounting surface of the wheel is positioned in front of the true centerline of the rim / tire assembly. This in effect brings the tire in to the fender well more. Conversely, a negative offset means the mounting surface of the wheel is behind the true centerline of the rim / tire assembly. This will cause the tire to stick out away from the vehicle.

Bolt Pattern

Each wheel has a different bolt pattern, and some wheels even have 2 different bolt patterns which allow it to be mounted on a wider range of vehicles.

Most Bolt Patterns are represented in the following manner:

4/100

* The "4" indicates the number of holes in the wheel for the bolts to enter and mount the wheel onto the car.
* The "100" indicates the diameter of the bolt circle measured in millimeters or inches. 4 & 6 bolt wheels are measured from the center of one bolt hole to the center of the bolt hole directly across from it. On a 5 bolt pattern, it is a bit trickier to measure without special tools. Imagine a circle running through the centers of each bolt hole. You would measure from the center of one bolt hole to the imaginary circle that lays between the opposite two bolt holes.

Part 2:
Finish

Once your new wheels and tires are installed, step back and take a good look. The new, sharper appearance will accent your vehicle splendidly. They look great now; but unfortunately, your wheels are often the dirtiest part of your car because they are constantly exposed to the elements (corrosive brake dust, ocean or road salt, stones, cinders and sticky tar).
Here are a few tips on how to maintain a wheel’s original splendor:

Before you install them, a coat of wax will help protect your wheels and make them easier to clean.

Treat the finish of your wheels as you would the finish of your car. Most alloy wheels today feature a painted and/or a clearcoat finish. The best way to take care of wheels without damaging their protective finish is by frequently washing them with a mild soap and water solution. Using a tar and bug remover can prevent permanent tar staining. Periodic waxing will protect the wheel’s finish from the elements.

Never use abrasive cleansers, steel wool pads or polishing compounds.

Beware of automatic car washes. Some washes use acid cleaners either before or during the wash to remove dirt and grime. Others use stiff brushes for cleaning wheels and tires. Both of these processes could harm your wheel’s finish. Ask the employees or manager of the car wash about their equipment and procedures before entering the wash.

Never allow your wheels and tires to be steam-cleaned. Hot steam can dull the paint and clearcoat finish on your wheels.

Don’t clean hot wheels; wait until they cool. Water dries much faster at higher temperatures. Thus, cleaning wheels while they are hot may cause your mild soap solution to dry too quickly leaving spots or a film of soap on your wheels.

Clean your tires and wheels first, one at a time. Tires and wheels tend to be the dirtiest parts of your vehicle and have a variety of surfaces to clean. So you will want to use the full strength of your hose to initially rinse away all loose dirt and to finally rinse off your soap solution. If you clean your tires and wheels first, you won’t expose your washed car to the over spray as you rinse them. Cleaning one at a time focuses your attention and ensures that the soap doesn’t dry on one wheel while you’re cleaning another. Be sure to use a different sponge on the rest of the car’s body to prevent scratching the paint from the particles that may have collected during the wheel cleaning process.

Clean wheels on a regular basis. Remember, they’re often the dirtiest part of your vehicle because they are constantly exposed to the elements (corrosive brake dust, ocean and road salt, paint-chipping stones and cinders and sticky tar).

Your new tires and alloy wheels are like any other valuable investment. You should protect them. Clean them as you would the rest of your car. Care for them as you would care for your entire vehicle.

Part 3:
Wheel Care

It is important to keep your wheels clean at all times. Your brakes will cause the wheels to heat up, and this heat in turn can cause any dirt or brake dust to cook in to the clear coat. If this happens, there's not a lot you can do besides having the wheels refinished. Protect your investment and keep your wheels clean!

Below are some simple instructions on how take care of your wheels:

* Do not use household cleaners or other detergents to clean your wheels. The best wheel cleaning solution is a mild soap and water solution (what ever you would trust on the paint of your car). Clean with a soft, un-abrasive cloth. Only on polished wheels can you use aluminum wheel polish. If you use this polish on chrome, painted, or clear coated wheels, you will only scratch or dull the finish.
* Do not use steam cleaners in automatic car washes.
* Do not use any tire cleaners on your wheels.
* Clean wheels when they are cool. Heat can effect the soap, causing it to dry on the wheel and become difficult to rinse off.
* Clean one wheel at a time. This also prevents the soap from drying on to the wheel.
* After the wheels are clean and dry, apply a coat of soft paste style wax to them. This will create a moisture barrier and help ensure the finish lasts as long as possible.

Hollander reference number

Hollander reference number is a unique part number that is assigned to each and every original factory wheel that allows us to easily and quickly identify the wheel in question.

Centerbore

This relates to the center hole in the wheel that centers the wheel on the hub of the car. Since most wheels are mass produced, they have a large center bore to accommodate several different vehicles. If this is the case, it is recommended that you use a hub ring. Hub rings are hard plastic or metal ring that fits between the wheel and the vehicle. This centers the wheel perfectly on the hub ensuring that there is no run out when the wheel is installed on to the vehicle. Without hub rings it is possible to get vibrations even if the wheel / tire assembly is perfectly balanced.

Torque

All alloy wheels should be installed using a torque wrench. This ensures that the wheels are not too tight or too loose. Check your vehicle's manual for correct settings. When you install wheels for the first time, you should re-torque wheels after about 100km to 150km (60 to 90 miles).

Alloy vs. Steel

The main differences between alloy and steel wheels lie in their durability and strength. Most high-performance wheels are made of an alloy and composed of aluminum, and other metallic substances. By using alloy wheels, you not only improve the looks of your vehicle but also the performance. The extra strength provides longevity as well as effecting tire wear in a positive manner. The weight reduction will improve steering response and handling, as well as help improve acceleration and braking.

This is known, it has the Audi/VW bolt pattern since it's an Audighini

__________________
RaymondQV
Countach QV Ex-Mimran #GLA12997, Urraco P300 #20530 sold in August 2008, Jalpa #FLA12203 sold in May 2006
www.countach.ch
www.jalpa.ch

When Frank Sinatra got his Miura S in 1970, he said: “If you wanna be someone, buy Ferrari - If you are someone, you own a Lamborghini”.

So, the difference between our stock 120mm bolt circle and the GM bolt circle is +0.6mm - a radius difference of +0.3mm or ~ .012 inches? Are wheels/hubs manufactured to those sort of tolerances? Particularly 'back in the day'? I'd bet not, variability being taken care of by the psuedo 'conical' portion of the bolt end seating in the wheel? Hence no surprise that the GM wheels, being so close, fit ...

Just my 2 cents ...

Bryan
'74 P250S S/N 15622
Indianapolis Indiana USA
blissinindy@yahoo.com

I next need to know what the offsets are on the Jalpa/silhouette wheels. I heard a rumor it was a zero offset??? Front same as rear???. Hard to find wheels with a zero offset. Would have to buy a modular 3 piece to fit right. Chrome Gallardo take offs would look great but wrong bolt pattern and offsets I think. Anybody know the Jalpa off sets?

In german it's called ET:

http://www.jalpa.ch/Techdata/index.html

__________________
RaymondQV
Countach QV Ex-Mimran #GLA12997, Urraco P300 #20530 sold in August 2008, Jalpa #FLA12203 sold in May 2006
www.countach.ch
www.jalpa.ch

When Frank Sinatra got his Miura S in 1970, he said: “If you wanna be someone, buy Ferrari - If you are someone, you own a Lamborghini”.

What a great site!!!!! How did I miss that section of the website. I wonder what the Bravo Wheels "ET" is....probably the same just wider rim in the back and front.
Thanks Raymond!