Chips, Gears & Speedo
Thread Starter
Le Mans Master
Joined: Jan 2003
Posts: 6,187
Likes: 309
From: SIMSBURY CT
St. Jude Donor '07 thru '25
Chips, Gears & Speedo
I have some questions if I change the diff in my 89 stock automatic from 2:59 to 3:07 then:
1) What difference will the 3:07s make from 0-60? (street tires)
2) Do I need to change the chip? If so, can a Hypertech chip be reprogrammed (I have a stock chip in the car and a Hypertech not in the car now)
3) Is the speedometer adjustment done by "reprogramming" or is there something else needed?
I won't be doing this myself but before I have someone do it I want to make sure I understand the whole process. Anything else I should be thinking about doing when the rear is being changed? (I know about checking u-joints). Thanks.
1) What difference will the 3:07s make from 0-60? (street tires)
2) Do I need to change the chip? If so, can a Hypertech chip be reprogrammed (I have a stock chip in the car and a Hypertech not in the car now)
3) Is the speedometer adjustment done by "reprogramming" or is there something else needed?
I won't be doing this myself but before I have someone do it I want to make sure I understand the whole process. Anything else I should be thinking about doing when the rear is being changed? (I know about checking u-joints). Thanks.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by CTYANK2
1) What difference will the 3:07s make from 0-60? (street tires)
2) Do I need to change the chip? If so, can a Hypertech chip be reprogrammed (I have a stock chip in the car and a Hypertech not in the car now)
3) Is the speedometer adjustment done by "reprogramming" or is there something else needed?
2) Do I need to change the chip? If so, can a Hypertech chip be reprogrammed (I have a stock chip in the car and a Hypertech not in the car now)
3) Is the speedometer adjustment done by "reprogramming" or is there something else needed?
2.) No. And no.
3.) The speedometer is uneffected by the programming. You will have to change the speedo gears and VSS to calibrate the speedo.
RACE ON!!!
