Engine

Wheels and Alignment

3 Aug 05 Wheels Our first attempt at wheels resulted in the front wheels hitting the brake caliper. These are the 17 x 9 Cobra III Deep Dish, with 22mm offset -- the dish is too deep. Discount Tire is sending a set of the Mid Lips with a 30 mm offset, the Mid Lip wheels are designed specifically to fit properly with the brakes. The formula to calculate backspacing given the offset in millimeters is (rim width in inches) / 2 + 0.5 + (offset /25.4) = backspacing. The 0.5 is the rim lip thickness in inches. 0.5 is somewhat standard and will get you close in the calculations. 16 Aug 05 The new Cobra III Mid-Lip wheel (30 mm offset) from Halibrand fits much better. The tires are gonna rub the inside fender a little, but I figured they would. Had to move the brake line a bit to clear the rim. It figures. The black plug in the f-panel is where it was originally positioned.

14 Aug 05 Knock Offs I wanted the look of real knock-offs, but also wanted to be DOT legal. (Most knock-off wheels are not DOT approved) So I've decided to adapt the knock-off spinners from Vintage Wheels to the Halibrand Cobra III wheels. Discount Tire has no idea when, if ever the Halibrand Spinners will arrive. I purchased one right-hand spinner from Vintage Wheels to see if it could be done. The picture to the right shows the Vintage Wheel knock-off I mated to the Halibrand wheel using an adapter I machined; its going to work well! S W E E T ! The Vintage Wheel spinners have to be modified to get an authentic look. The spinners are cone shaped on the back and recess slightly into the appropriate wheels. To simulate this look and move the spinner closer to the Halibrand wheel, some material had to be shaved off the back of the spinner, I'll probably cut the next three a little differently. The second picture shows are the adapter blanks ready for further machining and a hub to hold the spinner in the lathe while it was cut down. The adapter in the foreground was the first one, its in the photo as a reference.
Another problem is that the IRS axles protrude a little into the wheel center hole, so the center of the spinner adapter has to be bored to clear the axle.
See what I mean, its not much, but enough to cause problems. Besides, boring out the back of the adapter will reduce the un-sprung weight by a few ounces or so. Its interesting to note that the Halibrand center caps are held in place by an O-ring that mates with a groove in the wheel center hole, look closely at the wheel and you can see the groove.
Here's the adapters and hubs ready for the next stage of machining. There is still much to be done. These parts have to be finished and backing plates still have to be machined to hold the adapter in the wheel. I also need to order the other 3 spinners.
A few more machining operations later....
and the adapters are ready for threading... Top
and the last right hand thread adapter gets done.
Here the hubs get centered, drilled and taped for the stainless screws that will hold the backing ring on the adapter.
The knock-offs look pretty good on the mid-lip wheels too. Top
All of the hubs get faced to the proper length
The backing ring blank gets turned to the proper diameter.
Here it gets the holes drilled in it.
Here's one of the completed adapters.
If you haven't figured it out by now, the knock-off hole and therefore the hub shaft is larger than the hole in the Halibrand wheels, hence the need for a two piece adapter hub that installs from the front.

28 Aug 05 Hub Centric Rings I also made some hub-centric rings for the rear wheels so that the wheels are centered properly on the hub. Probably not really needed, but I do not like the idea of the lugs taking all of the vehicle weight, even if it is only 2200 pounds.
The wheels came with rings from Discount Tire, but they would only fit the front, not the rear T-bird IRS hubs.
The T-bird rear hub is 2.5 inches in diameter while largest part of the center hole of the Halibrand wheel is 2.867.
One of the rear Halibrand wheels with both the knock-off adapter and the rings installed. Top

4 Sep 05 Alignment Our setup for the alignment consisted of some turn plates, precut blocks of wood to set the ride height, masonite hardboard, and various spacers and shims. We leveled the wheels with shims and sheets of masonite using a laser level and target.
We got the car on the leveled turn plates and placed a straight edge across them to use as a reference to set the ride height. At this point the car does not weigh much, so we wound up backing the springs all the way off in the front and removing the coil-overs in the back. We are running 500 pound springs vice the stock 450's provided by FFR.
Obviously the rear was pretty far off. We used super glue and glued the IRS heim joint spacers together in groups of two and three, this still turned out to be a pain and it took most of the morning to get the IRS correct. We used 3 spacers on each end of the front joints, and whatever it took at the rear joints.
Here that same wheel has been aligned using our home-made caster/camber gauge. We used fishing line and followed the instructions on the FFR forum to set the toe. The alignment rear took the longest, the front went quickly.
All done, the ride height will be reset when the car is completed, and we'll will also recheck the alignment to be sure. Hopefully we will not have much if any bump steer with the 95 spindles and FFR Mark III.
We set all four wheels to -1 degree camber and the toe on each pair to 1/16 in total. The front wheels got -4.8 caster. I was shooting for 5 degrees of caster so the steering would return to center better, but 4.8 is close. Besides, the car will have power steering, which will counteract the effect of the caster somewhat.
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7 July 06 Tire Rub
After go carting around the yard and neighborhood, I noticed the rear tires rub a little. The 315s hit the front inner sheet metal , I will try to adjust it out using the IRS adjusters and re-align it. (This winter.)