q45t max tire size and lowering springs

[red one 96 q45t]

Hello to all the q45 enthusiasts. I just bought a 96 q45t for the wife last week but would like to do it up like I'd like it to be. First I'd like to say I live in Minnesota and drove to Milwaukee to trailer this car home (spendy). Primarily because the car originally came from Utah. Did the research through carfax and it was clean. 114k miles and running strong. As soon as I got it home I replaced the plenum hoses and vacuum lines and a knock sensor too. Really clean pearl white with tan interior, nonsmoker car. I am a mechanic by trade and used to work for an Acura dealership. Although I do not wrench on cars for a living anymore I love to do it at home. I build high performance Honda and other import engines out of my garage and have for 10 years. A few years ago we had a 97 q45 but I wrecked that one on the freeway on a rainy day. She loved that one and was disappointed when I trashed it. I think this one looks better but it's not as quiet and smooth as the 97. Anyway my question is what is the widest tire that I can put on this car is a 45 series tire on a 18-19 inch rim? Also any suggestions on the type of lowering springs would be appreciated (in the 1-1.5 inch drop). Lastly, what is the differential ratio, I've heard 4.08?

[MinisterofDOOM]

Welcome!

Read around the Q45 forum, lots of info.

I'm going to move this thread there, too.

[red one 96 q45t]

thanks for moving this over. I'm kind of slow when it comes to computers.

[maxnix]

A few years ago we had a 97 q45 but I wrecked that one on the freeway on a rainy day. She loved that one and was disappointed when I trashed it. I think this one looks better but it's not as quiet and smooth as the 97.

Hmmmmm......I would say something is amiss as it should be just as smooth (although the VH41DE is a vibration free engine, but the VH45DE shouold be pretty close) and the FGY33 may be a tad quieter with wind noise.

Largest tires on stsock springs are either 255/40-18 (OEM specified diameter) or 245/45-18, both on 8." 9" wide wheels, ~+35mm offset. Might be able to get the taller wheels on an 8", but it would be tight.

If you want to run staggered, you can run 9.5" or maybe 10" in back.

Pay attention to load ratings and you will eliminate almost all tires but Premium ones from top line manufacturers. Sticky tire thread in Infiniti General.

Welcome and post pictures.

[red one 96 q45t]

i'd like to post pics but not sure on how to do it yet. also I think 40 series would look even better, just concerned about not enough meat to protect the wheels. after all this is Minnesota where the pothole is king.

[Jeff Williams]

I would stay away from the 40 series rear tires because of the roads. You could go with a 255/45/17 or even a 255/45/18, but the radius would be off and she would be driving faster than the speedo says (which could be a bad thing).

I had 255/45/17 on some 8" rims on the back of Layla, and they drove great. I currently have 285/40/18 on some 9" rims on the back of Lola, but the speedo is off a good bit.

Most of the road noise issues are from poor quality tires. Michelins have, in my experience, been the quietest tires so far.

I wouldn't do the lowering springs, unless you plan to do something about the camber adjustment on the front and rear. Wide tires and lowering just add up to extra wear on the inside of the tires, unless you put some camber kits on the car. The camber kits for the 90 to 96 300ZX will work.