New look for my Barracuda

That is the setup on my kids car 69 notchback with a 318 My 67 is going to be a bit different setup. 408, OD 4 Speed manual, 3.73s I will turn 2700 RPM at 75 mph with 225s on the back. Thinking 255s on the rear on my 67 to drop my freeway RPM to 2500. Carry fix a flat and plugs, plus the 25.5" spare just in case.

Morning guys, wanted to share part of a reply on a Dodge Intrepid forum that I found as I was searching for other possible later model Mopars that might have temporary spares that would also fit the Barracuda spare tire well and match up with 225's or 255's. I realize the Intrepid is a 16" rim vs. the 15" and FWD vs RWD, but I was looking more at overall diameter. You'll see there are some possibles (though not as good as Matt's 02 Lincoln Town Car spare), and I know that at the recyclers around here (we don't have "junkyards", which I miss) usually have a good selection of Intrepids, Concords, etc. Just something to consider and research if anybody is looking for other candidates for spare tire donors:

"I have a 2000 Intrepid. The OEM spare tire is T135/80D16--its *calculated* outside diameter is 24.5 inches (622 mm), and I measured the actual outside diameter to be almost that when properly inflated to 60 psi (414 kPa). The OEM standard driving tire is 225/60R16 with a *calculated* outside diameter of 26.6 inches (676 mm); however, I measured the actual outside diameter to be about 1/2 an inch (12.7 mm) shorter, just 26 inches (660 mm) when properly inflated to 32 psi (220 kPa). (This particular tire of mine has been driven about 15,000 out of 90,000 rated miles = only worn 1/6th of the original tread...which may account for some, but I don't think all, of the discrepancy.) Surprisingly, this means that the OEM spare rides about 1.5 to 2 inches (38.1 to 50.8 mm) lower than the OEM standard tire! I'm not so keen on such a big difference! After the first flat tire I had with my Intrepid, I promptly bought a salvage wheel and tire to create my own full-size, conventional spare tire.

If you want a donut spare that more closely matches the *diameter* of the Intrepid's standard tire, then obtain/buy the donut spare of a Dodge Caravan or Grand Caravan with size T145/90D16 which has a calculated diameter of 26.3 inches (668 mm), very close to the Intrepid (only 1.3% smaller) and it has the same, matching wheel bore/hub size.

The second place I would look is to obtain/buy the donut spare of a 2007-2011 Dodge Avenger or '07-'10 Caliber (T155/90D16), which has a very closely matching calculated diameter of 27.0 inches (685 mm). NOTE: The Avenger/Caliber's wheel bore is smaller than for the Intrepid (67.1 versus 75.1 mm--not readily noticeable to the eye)--so before buying and going with an Avenger/Caliber's donut spare, measure the donut's wheel bore, because **my recommendation to use it could be misguided based on wheel bores.** However, my hunch is they use the same donut wheel bore for both, to economize--but be sure first. I don't know why car manufacturer's allow and promote use of spare tires that have diameters different from that of the standard tire size.

If you really want, you can even use the donut spare of a Charger/Magnum/Challenger, T135/90D17, which has a calculated outside diameter of 26.6 inches, the closest matching calculated diameter of these three (less than 1/4 of 1% different), even though the wheel/rim is 1 inch taller. This spare also has the same center bore of 71.5 mm, which means and makes the main load rest on the hub and not the lug studs. However, this spare's lugs and lug holes are 14 mm diameter, rather than 12 mm for the Intrepid and the lugs are spaced 0.35 mm farther outward from the center (5x115 mm versus 5x4.5 in/5x114.3 mm lug pattern). In other words, your Intrepid lug nuts would not seat *precisely* into the lug holes of this spare--and in torquing them, you *may very slightly* bend your lug studs outward or otherwise off center (again, not more than 0.35 mm).

I have heard no stories of anyone interchanging a 5x115 lug pattern wheel with a 5x114.3 having their lug studs sheer off and wheel fall off the car while driving, causing a wreck or permanent damage. Your lug nuts also could get a little scuffed when torqued down or possibly slightly distorted on their necks. The 5x115<-->5x114.3 interchange is commonly done--and frankly, the larger 14 mm Charger lug hole diameter partly compensates for the imperfection of this interchange *and* the matching center bore keeps the wheel properly aligned = I would think very minimal total risks. And you're not supposed to drive over 50 mph (~80 kph) on your spare, anyway = further minimizing risks of an imperfect interchange. The imperfections introduce changes in lug nut and stud positions of less than 4% for 14 mm lug holes drilled to 18 mm (4.5% for 12 mm lug holes drilled to 16 mm--which is the measure from my Intrepid's donut spare). Such interchanges are done routinely by owners of performance, racing, and show cars.

Lastly, two cars I did not find examples of their spare tire sizes but which otherwise match the Intrepid, are the Dodge Nitro and the Prowler (all makes). So you could check those too."

Don't know if that helps any, but thought that 225/60's came on my Intrepid and wondered if they would match up.