jmm98LS1

iTrader: (28)

I've got 4.56 gears in my new 9" rearend. In HPTuners, when I calculate the tire/gear ratio (26/4.56 = 5.46) and click commit it says invalid entry! It won't let me input anything lower than 6.00. Is there a way to make this work or is this yet another reason to despise tuning a '98?? I'd really like my speedometer/odometer to read correctly.

foff667

iTrader: (2)

I think its mainly due to the VSS Pulses per mile constant maxing out.

chromeplated500

iTrader: (10)

Yeah +1, I remeber a thread a while back with the same deal and a 99 PCM didnt fix it.

jmm98LS1

iTrader: (28)

No way around it? So is this a '98 only deal or is everyone with 4.56 gears running a bunk speedometer?

7420NW7TH

iTrader: (8)

Who needs a speedometer?

jmm98LS1

iTrader: (28)

Me.....I'm more concerned with the odometer.

jmm98LS1

iTrader: (28)

Ok, so the lowest gear ratio you can go with factory 26" tall tires is 4.33's. Any lower than that goes beyond the limits of the pcm. By my math, running 4.56 gears while the speedometer thinks they're 4.33's would leave my speedometer reading 4mph fast at 70mph (speedo says 74 when I'm going 70). Any math wizards wanna double check that? I could live with 4mph off if I figured that right. My head hurts.

Rhino

iTrader: (6)

Why not try tricking the PCM by modifying the tire size?

jmm98LS1

iTrader: (28)

Can't do it with a '98. Sounds like best I can do is get in the ballpark....'98s suck *** in the tuning world.

Sharpe

iTrader: (7)

@ 98's.

Did you ever get your power problem solved and if so, what was the deal?

jmm98LS1

iTrader: (28)

Haven't had it back out yet, but I'm 97.4% sure it was the converter. Now it's a six speed, so that's solved.

Sharpe

iTrader: (7)