Retuning PCM for new tires?
10-26-2011, 06:38 PM
#1
Retuning PCM for new tires? Hey guys, just wondered if this is something I could have locally done or not. For new, bigger tires the PCM obviously needs to be tweaked to read the bigger tires, my question is, do I have to send my PCM off somewhere or is there anywhere in the DFW area that can do it on the cheap? I already have a tune so I don't need a whole new tune. This doesn't sound like a job for AutoZone or Pep Boys, but if you guys know anywhere, and if so how much I could expect to pay, it would be greatly appreciated 
10-26-2011, 06:41 PM
#2
HPTuners (usually runs you $100 for the cost of credits to tune your 98 V6), Dyno Tune at a performance shop (more money), or Dealer can SOMETIMES recalibrate, but that'll be REALLY expensive.
You COULD just take the needles off and adjust them yourself. BAHAHA. jk. That won't work.
Seriously though, the differences are sooo minimal.
You COULD just take the needles off and adjust them yourself. BAHAHA. jk. That won't work.
Seriously though, the differences are sooo minimal.
10-26-2011, 07:33 PM
#3
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unless you went some ungodly size bigger than stock will only cause speedo to be off by small percent
you didnt put 26s or anything on right
you didnt put 26s or anything on right
10-27-2011, 01:45 AM
#6
Well going from 235 to a 285 is a big difference, a 15% difference actually. If I was going 69 mph my car would show 60 mph. The mail order tuning thing is a bitch, I was a young dumb kid in high school, went with PCMForLess. Ok tune and all, but made things like this more difficult.
Hindsight is 20/20
Hindsight is 20/20
10-27-2011, 05:56 AM
#7
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Well going from 235 to a 285 is a big difference, a 15% difference actually. If I was going 69 mph my car would show 60 mph. The mail order tuning thing is a bitch, I was a young dumb kid in high school, went with PCMForLess. Ok tune and all, but made things like this more difficult.
Hindsight is 20/20
Hindsight is 20/20
give the full tire size.
go to any shop with HPtuners and they will do it for you. (most shops already have unlimited credits) so the cost should be cheaper if that's all they're changing.
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11-02-2011, 11:08 PM
#10
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Are you sure you weren't running a 235/55/16?
235/35/16 is about 4 inches too small for the stock sized tire. Also, comparing the 235 to the 285 isn't how a tire height is measured. That's the width of the tire, and the 2nd number is going to affect your sidewall....
For instance a 235/35/16 is 235mm wide and the sidewall is 235mm multiplied by 35% will give you your sidewall.
Needless to say, a 285/40/17 isn't a significant differnce from the stock set up.
235/35/16 is about 4 inches too small for the stock sized tire. Also, comparing the 235 to the 285 isn't how a tire height is measured. That's the width of the tire, and the 2nd number is going to affect your sidewall....
For instance a 235/35/16 is 235mm wide and the sidewall is 235mm multiplied by 35% will give you your sidewall.
Needless to say, a 285/40/17 isn't a significant differnce from the stock set up.
11-03-2011, 10:19 AM
#11
Your numbers must be off like noted above. No way in hell you were running a 22.5" tire (235/35/16). I did a quick search at online tires and I came up with 0 results in that size.
To determine tire height, take the first number (235) and divide by 10. Then divide by 2.54. Take the result from that and multiply by the second number (35) divided by 100. Take that result and multiply by 2 and then add the wheel diameter.
235 / 100 = 23.5
23.5 / 2.54 = 9.25
9.25 * 35 / 100 = 3.24
3.24 * 2 + 16 = 22.5" Overall tire height
To determine tire height, take the first number (235) and divide by 10. Then divide by 2.54. Take the result from that and multiply by the second number (35) divided by 100. Take that result and multiply by 2 and then add the wheel diameter.
235 / 100 = 23.5
23.5 / 2.54 = 9.25
9.25 * 35 / 100 = 3.24
3.24 * 2 + 16 = 22.5" Overall tire height
