3 wks ago i swapped my stock wheel setup on '90 Q for a 18" setup.Orig: 15" piepans W/ 215/60(or 65 can't remember) 15 tires, i think the suspension is oem also.New: 18" wheels, Tires are (4) 245/45/18
I was expecting to have to do an alignment after the job, but the car drives in a straight line now without the alignment. What happened here? If the orig tires were 65profile then the overall diameter old to new has a 2.1" size increase. However if the orig tires were 60profile then the change is a 4.8" increase. Are these increases enough to warrant an alignment? Did the gods smile on me and allowed me to save some money or should i take it in for an alignment even though it drives straight?
To align or not align?
-
JT_MONEY_2004
- Posts: 409
- Joined: Wed Jun 30, 2004 12:14 pm
- Car: 1990 Q45, Pearl
the overall diameter should not have significantly changed,you have taller wheels,but shorter tires. the alignment numbers should not be affected at all by the new tires-the only alignment spec that can be adjusted on the q is toe in/out,which changing tires should not affect at all.now,if the alignment was off before the tire change,it will still be off! worth a check to preserve your new investment,imho!
-
JT_MONEY_2004
- Posts: 409
- Joined: Wed Jun 30, 2004 12:14 pm
- Car: 1990 Q45, Pearl
Re: (911/Q45)
And that mean...............align?
-
Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (qship96)
Remember the alignment specs are mis alignments numbers -------the amount you have to offset from pefect so that a brand new car with new suspension [shocks, rubber bushings true arms] tracks perfectly down a smooth non cambered road at 55 mph with minimum tire scrub.
They are arrived at by at speed measurements in the design phase of a car, therefore you must [may have to] use different numbers as a vehicle ages --- bends and wears.
Alignments are an every 6 months fine adjustment as the bushings wear between the 4-6 year replacement period.
The problem with static mis alignment [adjustment] is you don't know what is NOW the correct number............tire examination is the only easy clue.
They are arrived at by at speed measurements in the design phase of a car, therefore you must [may have to] use different numbers as a vehicle ages --- bends and wears.
Alignments are an every 6 months fine adjustment as the bushings wear between the 4-6 year replacement period.
The problem with static mis alignment [adjustment] is you don't know what is NOW the correct number............tire examination is the only easy clue.