Mazda Repair: steering, wheel alignment, suspension models

Question
hi this is my fourth post to you and all ans have been great. couple of questions. on my 2007 sv is this a interference motor 2nd on your recomendation i put the dz101 215 50 16 on and the car rides nice. i work for a gas co.so i put nitrogen in them and set it at 30psi. now i dont have to worry about hot and cold pressure; with nitro it always stays the same.3rd i have the car about two mos now and maybe i just got used to it or its my imagination but it seems like the go kart handling is gone. it seems like i have to correct the steering more than normal. car has 18K now and was thinking about going to mazda and get a wheel alignment not that the car pulls or anything but just for the hell of it. also is there any way to make the steering faster than the 15-1 ratio. like i said before maybe  i just got used to all the miatas charactoristicks and its just in my mind. what are your thoughts on all this stuff.

Answer
The engine is an interference design.  Be sure the belt is service by 60k.

It is common to grow accustomed to the feel of your Miata.  As time and gravity take effect on the springs the rate will vary and the range of support will also vary which will translate into a change in feel and response.  This affects all suspension systems.  OEM base systems tend to ride rather soft from day one so as time passes they will seem to change quicker than the sport suspension models.  After market replacements will correct this however, they too eventually fall victim to gravity and use.  I find OEM systems tend to offer 35k to 50k (3-5 years) of acceptable ride quality to the discerning Miataphile.

As for handling on your model, it is likely your tires made some change.  That coupled with some settling in the suspension would warrant a re-alignment.  Depending on where you live and how you drive, alignment checks are common place every 25k-30k.

The suspension, though tough, is tubular and not as forgiving by design to harsh conditions as the older models were so re-adjusts should be expected on regular intervals.  Trust your senses, if it doesn't feel right it probably isn't.  A Miata is an extension of you and should "just feel right".

The steering ratio is fixed and not changeable.  In older models manual steering was available which had a different ratio more suited for performance and racing applications.  No manual (non-assist) racks are offered that I am aware of.  I will check with my technical counterparts at Mazda competition and let you know if such a beast is being offered in the race field.

service@miatashop.com