Question. Why did you move to a lower profile tire from stock? I would have used the stock profile to better fill out the wheel well. Plus you'd get an even better ride. If you'd have used a 285 or 295/35 and 245 or 255/40, you have more than enough rubber and a little less rear width to contend with.

I recently bought new rubber for my DB7 and actually increased the profile front and rear to improve the ride. Plus the large arch gap at the rear was reduced, improving the looks. Went from 245/35-19 to 245/40 up front and 265/30-19 to 275/35 in back.

 

He did say he couldn't find any nuts shorter than 2 inches, implying that he didn't need nuts that long. And I doubt the lugs stick out any where near that much. Like I said, 1.4" nuts are available from gorilla, which will look a whole lot better.

 

when you go to 20s, the ride will not improve, handlng usually is sacrificed due to less compliance with the tire, due to an even shorter sidewall. (in the race community , the optimal diameter is in the 18-19" range.) But, the tire compound and construction is also very important, as 007 saw with the michellins. a softer tire is always better than a tire made of "stone". if you guys don't drive more than 5k miles per year, why don't you try a DOT racing tire like a R888 Toyo? its 2x the tire of any street tire you will ever try...... night and day. Put it this way, if OO7 saw a difference of the michellin vs the Bridgestone by a factor of 2, a real DOT racing tire, even full tread, would be 10x the difference.


again, as far as the weight savings go, for every 1lb you save on the tire, its like sheding 2x that if it was sitting in the car...... (see previous thread for proof of that, dispelling a lot of the myths in the automotive world of 4x or 10x .. )


by the way.... great job on the write up and the results.......looks great. by the way, if you go to a 3piece design, you could get each rim to be around 19lbs for a 10 and 11" set up. .... but as you pointed out, that usually costs about $5k for the set.

 

personally, I think the profile looks very stock.... if you think about it, he went from a 235 to a 255, and then just went down one notch with the profile ratio. end result is actually a little taller than stock. his ride height looks a little high, but that's just the variation of car to car. (gap of the tire vs fender)

 

For the fronts he went from the stock 26.40in diameter down to a 26.03in diameter.

In the rear, he went from the stock 26.58in diameter down to a 26.20in diameter.

So, Steve is right, he actually went to a smaller diameter (shorter) tire in both front and rear. Had he chosen different ratios, he may have filled the wheel wells more, but maybe the Michelins weren't available in those sizes.

 

Because maybe we don't want a rock hard, noisy ride? And good luck trying to find R compounds in 20" diameter.

 

By changing the tire sizes for the rear of your DB7 in the way you described, you increased your overall tire diameter by 1.32 inches which is quite a bit. While it will certainly fill the wheel well much better, you also reduced the revolutions per mile from the previous 798.43RPMi to a much lesser 758.81RPMi which would cause quite a variance in your speedometer reading. Be careful so you don't have to explain to the cops why your speedo says you were going much slower than their radar did.

 

Hey Karl thank for the comments and the rep!


Regarding the bolts, I think I may invest in a set of custom bolts. Due to the concave nature of the rear wheels, the bolts do stick out more than intended from an appearance standpoint, but the actual exposed stud is exactly the same front and rear. What I plan on doing is getting 1 custom nut made, then testing it using blue dye. By placing blue dye on the front of the thread and the tip of the stud I will thread it in all the way to see exactly have how far the lugnut will go on the stud and guage if I can run a 1.5" There was definitely a lot of excess (roughly half inch) so 1.5" would be cutting it close. I would only do it if I could do a full torque on a 1.5" Lugnut, that half inch would make a massive difference. However the difference in price between standard lugnuts and a high quality custom set could be hundreds of dollars so again.... for now these will do as a temporary solution.

 

Hey EZ,

Unfortunately the Aston center caps do not fit... with that said the forgestar center caps are actually a much higher quality design with rubber O-ring and etc. what could be done is you could probably custom apply aston center machined logo and use super strong adhesive to attach to the caps and that should do the trick, but right now I have't put too much though into it as it doesn't bother me that much. I have many more important projects still in the works I want to finish up first before I go back through the finer points on the car.

 

basciallly, if those are the dimensions are close to the same. 26.4 to 26.2 is less than a quarter inch, radus thats less than 1/8" diff. hard to see. so basically the same. but the wider tire and different sidewall design, makes it look the same. the 20s do look good though pretty hard to fill out the wheel well with tire size, without making the tire look pretty silly. you have a 2" gap, that would be a 30" truck tire to close.

 

You have to maintain the proper overall rotating diameter/radius the same. By going to a 255 wide tire, 35% profile height comes out to the same overall diameter as a 235 @ 40% profile.

You have to remember that the profile number is just a % of the overall width. naturally as the overall width gets wider, you have to compensate the % in order to maintain the overall same height. a 235mm/40 has the almost exact same sidewall height as a 255/35 (or close enough given the options available). It may sound different but its not. Tirerack provides relatively accurate overall rolling diameters so you can compare making sure that not only your new tires setup has the same rolling diameter as stock, but also same from Front / Rear (also crucial to make sure speedo is accurate on our cars as our Speedo pickup is oddly off the front wheels and not the rear wheels).

 

Just measured the stock AMv8 tires front and rear.
25.2" front
26.0 rear.

so again both have about a 2" gap on top of the tire to the fender.

dont believe tire specs, they are usually all over the map.

 

Speedo is very optimistic, so larger rear diameter makes it closer to accurate, but still reads too fast. So, better ride, better looks and better speedo. Can't go wrong.

I'm in the process of getting some new wheels for my other DB, and will probably go taller profile for those as well. I'm not a real fan of the bandaid look any way. Plus I do like a more compliant/quiet ride. Certainly not going to go wider than stock. All that does is make for a heavier rotating mass for a marginal increase in grip.

 

Who said you had to do that? There is nothing wrong with going taller (or shorter) as long as the front to rear ratios are maintained reasonably close. And as far as the speedo is concerned, they always read too high, so going taller doesn't hurt too much. At most it may cause it to read slightly lower, but in some cases like my DB7, it still reads too high.

 

Yep, as with most cars too! I put 305x35 x 18 on my race car, stock clad with 245x45x17s and the much taller tire, actually made the spedo accurate. so generally, most cars read a little higher than actual.