Gear swap question!

[Waterboy2b98]

I am thinking about doing a gear swap, and have been reading up on all the threads. Sounds like doing a 3.91 will be cheaper labor wise than 4.10s due to shimming, got that.
My question is when they have to recalibrate the speedo, will that mess with the custom tune Lethal racing did?? That I have not read that anywhere??

[blazzin1]

Swapping gears....labor wise....will be exactly the same regardless of what gear ratio you go with. 3.91's will be cheaper than 4.10's because AAM 3.91 gears are significantly less expensive than Richmond 4.10's. That's the only reason.

Can't answer your tune question, sorry! I would guess that only the speedo could be adjusted while leaving the rest alone, but I am certainly not knowledgeable on the subject.

[mdub76]

Just take back to lethal and they can change it in the tune

[JCunningham]

well if useing the AAM GM 3.91 gears i have not heard of one person that needed a install kit. the 3.91 gears are much cheaper. the richmonds will need a kit. The only thing that gets changed is the speedo calibration in the tune. the engine tune will not change. How did you have the tune done? If you had it dyno tuned at Lethal you will need to bring it back to them. takes 5min to change and you will be on the road. If you have a hand held tuner just email them and they can change it and email you the new tune.

[SSDan]

You can change the gear ratio via tuning software and not affect your custom tune. Mine was tuned by Vengeance with EFI Live and after my gear change a car buddy used HP tuners to reset my speedo. All he did is go to the table that shows the rear gear ratio and typed 3.91 over top of the cell containing 3.45. That was the only change needed. He uploaded that change and all is good.

Of course if getting to Lethal is convenient for you that's the easy way to go. And like stated it takes 5 minutes.