What do you need to race?
Aug 1, 2017 | 10:02 PM
#11
TECH Junkie
Joined: Jan 2007
Posts: 3,309
Likes: 265
From: Arlington, TX
That was pricy imo. Lift the rear with a jack on the center of the diff. Put the valve stem at the bottom with trans in neutral and have someone rotate the tire exactly once while you are under and count the rotations of the driveshaft. That will tell you your ratio. It was a huge difference on mine but I was 4l60. I went from 9.54 with 3.42's to 8.90 with 4.10's at 5 lbs and a very mild tune. Same weather and everything. It should be dramatic.
Aug 1, 2017 | 10:59 PM
#12
That was pricy imo. Lift the rear with a jack on the center of the diff. Put the valve stem at the bottom with trans in neutral and have someone rotate the tire exactly once while you are under and count the rotations of the driveshaft. That will tell you your ratio. It was a huge difference on mine but I was 4l60. I went from 9.54 with 3.42's to 8.90 with 4.10's at 5 lbs and a very mild tune. Same weather and everything. It should be dramatic.
Aug 2, 2017 | 10:51 AM
#13
You guys have to remember, he was in Denver CO. That track is a mile high to start with and I'm sure it was hot that day! lol. It's hard to make boost when you're at 9000'+ DA. And you have to make about 2.5lbs of boost just to get to sea level air pressure. I think he did pretty good considering the air conditions. Take that thing to sea level on a cool day and you'll be amazed at the difference! 
I wouldn't spend too much effort on getting the tune dialed in up there unless you're going to be there a while. Because it should really be dialed in at a lower elevation if that's where your going to run it the most. The gears probably don't feel like they added that much because of the elevation your at right now killing power. It's huge!! I grew up in Wyo about 2.5 hours from there so I'm all to familiar with what a hp robber is from elevation. When I would got to Phoenix to "winter", it was amazing how much better my truck ran down there.
I wouldn't spend too much effort on getting the tune dialed in up there unless you're going to be there a while. Because it should really be dialed in at a lower elevation if that's where your going to run it the most. The gears probably don't feel like they added that much because of the elevation your at right now killing power. It's huge!! I grew up in Wyo about 2.5 hours from there so I'm all to familiar with what a hp robber is from elevation. When I would got to Phoenix to "winter", it was amazing how much better my truck ran down there.
Aug 2, 2017 | 12:36 PM
#14
You guys have to remember, he was in Denver CO. That track is a mile high to start with and I'm sure it was hot that day! lol. It's hard to make boost when you're at 9000'+ DA. And you have to make about 2.5lbs of boost just to get to sea level air pressure. I think he did pretty good considering the air conditions. Take that thing to sea level on a cool day and you'll be amazed at the difference!
I wouldn't spend too much effort on getting the tune dialed in up there unless you're going to be there a while. Because it should really be dialed in at a lower elevation if that's where your going to run it the most. The gears probably don't feel like they added that much because of the elevation your at right now killing power. It's huge!! I grew up in Wyo about 2.5 hours from there so I'm all to familiar with what a hp robber is from elevation. When I would got to Phoenix to "winter", it was amazing how much better my truck ran down there.
I wouldn't spend too much effort on getting the tune dialed in up there unless you're going to be there a while. Because it should really be dialed in at a lower elevation if that's where your going to run it the most. The gears probably don't feel like they added that much because of the elevation your at right now killing power. It's huge!! I grew up in Wyo about 2.5 hours from there so I'm all to familiar with what a hp robber is from elevation. When I would got to Phoenix to "winter", it was amazing how much better my truck ran down there.
Aug 2, 2017 | 06:18 PM
#15
Im at 3,400' in rapid city and driving around the black hills gets up to 5,100' so I figured tuning in denver would be ok. Wont the computer compensate for the elevation change? There are no competent tuner/dyno operators near me so dont have many options. You no any good ones in Wyoming? I spent a few years in Lander Wy.
I forget you're out of Rapid, was thinking back east for some reason. Wouldn't hurt to have a Denver shop check it out. Look up J&S Performance and Tuning and tell them I sent you. They are pretty good guys in Arvada.