When shopping for new MX5 Miata wheels and tires there are a couple critical issues to consider:
Weight. The Mazda MX5 Miata is very sensitive to what is called unsprung weight (which can best be understood as what hangs off the Miata suspension rather than what sits on it). We therefore strongly recommend that you use only light weight wheels for your MX5 Miata like those we sell here. Unlike other vendors who rely on overly optimistic wheel weights as listed by the wheel manufacturers, we weigh each wheel that we sell to verify the weight that we list! For that reason, some of our listed weights here are slightly higher than the marketing weight listed on the wheel manufacturers' websites.
Offset and Size. Offset causes a lot of confusion. Here is a simple explanation. If the rim is 6 inches wide, and the mounting surface of that rim (backside of the bolt holes), is 3 inches from either outside edge, that rim has a 0 offset. To the extent that a rim's mounting plane is offset from that zero position, that offset is measured in millimeters for Japanese cars. For the 2006-2015 Mazda MX5 Miata the factory offset is 55mm for the 17 inch size. Street users considering a wider stance but staying with stock width tires may consider offsets down to 42mm. For Miata owners looking to go wider than the factory 205/45/17 MX Miata tire size, we suggest our many 48mm offset choices in widths of 7.5 and 8 inches for street use, or autocross or track work. Our 45mm 18x9.5 Enkei RP-F1 is intended as a race application only. Please contact us if you have any questions on appropriate MX5 Miata wheels and tires for your intended use.
MAX SIZE. Folks ask every day what is the MAX size they can install on the 2006-2015 MX5 Miata without rolling fenders? The max tire size that fits in stock MX5 Miata fenders is 235/40/17 and our street users usually put that on 17x8 ENKEI PFO1 and our autocross and track customers usually put that on 17x9 Enkei PFO1. Note that offset is critical....those PF01 wheels are 48mm and 50mm choices to get that 235/40/17 under stock fender lips...and you need some negative camber to clear (at least -1.3 negative). However, our most popular autocross 17x9 is the Enkei RPF1 (lighter and cheaper) which has a 45mm offset and requires a fender lip roll for 235/40/17 or more tire (STR customers often using 255mm wide tires but that requires a VERY substantial fender lip roll).
Shop our MX5 2006-2015 Wheels and Tires catalog by clicking below:
After reading many other positive reviews on both the GWR and Miata forums I finally decided to buy this product. My main concern for many months was whether or not I was up to the task of installing the header. But with the excellent instructions on Brian's forum as well as several Miata forum threads it turned out easier than I expected.
After receiving notice that the header would arrive on a Friday afternoon, I began the disassembly process. After about 3 hours I had the stock manifold out. Later that afternoon the new catted header arrived right on schedule. And it is a thing of beauty. I opted for the stainless version. Installation on Saturday morning took another 3 hours, although I could have shaved some time off of that but I was actually enjoying the process of double checking torque values and cleaning up my engine compartment. I already have the GWR catted midpipe, so that connection was a snap.
I put everything back together, reconnected my battery, and went for a drive. NO CODES! Nice throaty sound with my RSII muffler, and a significant boost in power and low/mid torque. Another happy camper here. I since have added a M-E tune and I feel I have realized all of the gains that Brian has achieved on his 2012 project Miata. I've put several hundred miles on my Miata since the install with zero problems. This is the car that Mazda should have built all along. Thanks Brian.
-- Ron P.
Last week I spoke to Brian, I ordered a aluminum Koyo 37mm radiator for 97 Miata.
Brian, you run a first class show! It arrived the next day. It is a fully polished work of art. The welding is perfect. The fit is perfect, old radiator slipped right out, new one slipped right in. Perfect. I am very pleased. Thank you.