Very nice thank you for the info, anyone else put gears in their Shelby if so what is the 411 on the results.
Busa,
I may have missed this point through your thread, but please refresh my memory....what are you wanting to accomplish?
Mine are 3:73 for 2 reasons-
a) Because I thought it would result in slightly better every day driving from a dead stop. I was right.
b) I did the same ratio graph as the other poster and did so because my goal was to get 65 mph up to 2,000 to get my Ford Racing axle backs out of the drone zone. It did. In 6th, it makes about a 275 rpm difference at 65mph. Perfect. There is little to no difference in economy at those speeds. It's above 2,200 that the economy begins to suffer.
Someone else mentioned high rpms as the Achilles to these motors and they're exactly correct. But, it's HIGH rpms (above 6,500) that grenade these things. So far, SVT has only two cases of complete failures due to high rpms. A few hundred rpms at cruise isn't going to cause premature wear.
That said, you mention the pulleys voiding your warranty. They don't. Nothing voids your warranty unless it's explicitly named as such (ie "the installation of this supercharger will void your factory warranty". This verbiage is all over the FRPP catalogue). Now, IF you had a failure that could be directly linked to the increased pressures, heat, etc then you're screwed.
Same goes for the swap of a gearset. IF they proved that a failure was dueto increased rpms....installation problems...increased NVH due to an aftermarket gearset, you're screwed.
So, in a nutshell, ANY aftermarket part COULD result in a refused warranty claim, but unless it is specifically stated, this is NOT automatic and has to be proven that the part or service is a direct or indirect culprit. For the record, they'll probably win, but that's the risk you take.
Want some REAL risks? Watch what happens when a handling related accident occurs on a car that's been lowered....is shod with aftermarket wheels and tires, etc.
Hope this helps.
BTW- Mine has the Evolution Ultimate Handling package installed and I have the Metco 2.6 and idler sitting here to be installed in a week. As you know, I have a JLT and an Evo tune. Am I screwed? Only if something breaks
bj