BigIron5

I'd like to run a 19" wheel, but I don't want to give up too much comfort. In my experience, and what I've heard here backs this up, 45 series tires are the sweet spot between looks and comfort.

Can I run a 45 series tire, on 19" wheels, on my 1999 LS400?

If so, what other parameters will I need to stick with (tire and wheel width, suspension height, etc.)?

RA40

iTrader: (6)

This tire calculator will get you going:
http://www.anycalculator.com/tiresize.htm

PSTracer

45 is too fat with 19" wheels. 30-35 is normal.
if you want to drive comfortable, try 17"
18" wheels fit 45, i'm using 225/40 on 8j and 235/40 on 9.5j

sha4000

iTrader: (1)

I have 40 on my 19s and they don't look bad IMO and gives me some protection from the NYC potholes. I could never drive around with 30/35.

Kingsoup

I ran 255/40/18 on my 93 and it was pretty good, 263/30/19 on the new car is HORRIBLE, bang bang bang, avoid at all costs!

timmy0tool

iTrader: (7)

correct! use this to get the proper tire size. remember the series is a percentage of the overall width of the tire. a 225/45/19 (4" sidewall) will be thinner than say a 265/45/19 (4.7" sidewall). comfort also depends on suspension and tire brand/type.

how wide of a tire are you looking to go? then we can tell you what series will be best. generally folks with 19s run 35-40 series.

pejayz

235/35-245/40 19x8.5-19x9.5..hopes this helps you

NYKnick101

you can run 45's but you would have to see if the size will cause any issues in your wheel wells. It could mean you rubbing like crazy on time you attempt to turn. Do they even make 45 profile for 19's? I think the dodge challenger runs a 45/19 tire if if you want for comparison