Quick question: when you upgrade to a 4.08 I understand that redline is higher, but is the tachometer still accurate? Is the speedometer still accurate? How can you get them calibrated if they aren't?

 

They're both fine, no need to get anything re-calibrated.

 

Your redline isn't raised though. Your cruising RPMs are higher (ie at 80 mph in 6th it jumps from 3K to 3.5K rpms, not exact but you get the idea), but you can't instantly rev higher.

I've heard the speedo might be off for people with Auto trans.

 

What year is your car?

 

Good Lord, I think 6th is to low now....


I wish there was a way to drop the RPM in 6th to about 2500 at 70 mph.

 

I bet swapping in the 3.3 FD from an Auto would do that, but then your acceleration would be pretty sluggish. Unless you're highly boosted and tuned...

 

Oh yeah, it would, I'm talking about just changing 6th only. I mean, it runs the same speed in 5th or 6th, why not make it an economy gear.

 

Yeah, that would be nice. A serious overdrive would be awesome, same fun gearing in the twisties, economy while cruising on the highway.

 

what kind of gas mileage drop did you notice with the final drive change? and what/how much did you notice on the acceleration end?