Dear guys, HRE 547r 8' & 11' x 19' What size combo would you go for it? I will lower the car with H&R springs. Thankyou all. a) 235/35/19 & 295/30/19 b) 235/35/19 & 305/30/19 c) 235/35/19 & 295/35/19 Billy
Here's what I have for 19's; 225/35-19 fronts 285/35-19 rears Speedo is now dead on with the OEM tires. If you go bigger, check with: http://www.miata.net/garage/tirecalc.html This will allow you to compare the OEM to what you want, and it will tell you what change if any will occur.
I don't know that aspect. However, put into the calculator the 235/35 x 305/30 x 19 that cig1 stated, and see what that does to the overall speedo, etc.
I believe what's more important than Speedo readings, they can be calibrated, is the ratio between front and rear. The front to rear ratio is what feeds the ASR system. GCalo, your combination, to me, works fine. My objective was to fall somewhere between the OEM Modena and Stradale ratio. G
FWIW, I'm under the impression that the ASR mostly (if not entirely) works by comparing the rotation speed of both rear tires and only the rear tires. When it senses a reasonable difference in rotation speed, it assumes one of the tires has lost traction and is slipping....it then cuts the power. When making a fast turn, the ASR often comes on just because it mistakenly thinks the tire slippage is due to loss of traction...when in fact it's just the difference between the inner & outer arc of the turn. So Gary....bet those tires looks FAT & WIDE huh? I'm tempted to make the same jump as well. Any issues with that size at all?
You may be right on what triggers the ASR, but if that's the case, what difference would the tire size make if they were taller or smaller. There was a lot of discussion regarding tire sizes and ASR a while back. G
Cig Interesting work on the spread sheet. What width are your rims to get the 305's on? Those are huge! I am going to run your sizes on that calculator to see what's happening.
If I'm not mistaken, they are 11" on the rear. That was a step down from a Novitec setup which ran 355/30 on 12". Personally, I felt they were overkill. I need those 305's to keep up with Jeffrey in his Stradale on 285's ... he pushes hard G
