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TurboDiverArt
08-01-2006, 05:37
Hi All,

Just ordered the new tires for the H2 rims. The new tires are 31.6
ronniejoe
08-01-2006, 05:39
That's correct. It's a straight linear multiplier. Since we beat to death the speedo change stuff in the gearing thread, I assume you'll be recalibrating?
TurboDiverArt
08-01-2006, 06:42
That's correct. It's a straight linear multiplier. Since we beat to death the speedo change stuff in the gearing thread, I assume you'll be recalibrating?
Initially no. Although I haven't calculated the new effective ratio, it's not too severe from the stock 3.73's with 30.5" tires. I'd be surprised if the effective ratio was much more than 3.60's. If it starts to really annoy me being out of whack I'll get a recalibrate and do it. For now I think I've spent enough on the rims and tire combo.

Art.
redbird2
08-01-2006, 20:11
it is fairly easy to adjust the VSS to get the correct calibration the 6.5 diesel book Jim put togeather has a real good section on how to make the adjustments I did mine last yaer when I converted the truck to 6.5 as I changed over the harness from the donor truck which had 3.64? not sure dont remimber my truck has 4.10s so it made huge difference If I remember right about 1 hour total to make the change. Good luck Greg
TurboDiverArt
08-03-2006, 10:50
I'm only off by 3 MPH at 65, I'm not sure if it makes sense to change it around. I've never seen the article for adjusting the VSS but I assumed it was not tunable to exact gear ratios. I always for whatever reason assumed you could only set it to 3.42, 3.73 or 4.10's. I'd have to calculate what the effective gear ratio would be when changing from stock tires (believe 30.5") to 31.6" tires with stock 3.73 gears.

I have noticed that when going 62-63 MPH on the speedo (really about 65 MPH) that my RPM's are just below 2000 where before they were 2100-2200. The tires are quite and a little less engine RPM never hurt either in the area of noise reduction.

Art.
Warren96
08-03-2006, 13:44
I wasn't going to put in my 2c until I noticed that your from my area and that you may have noticed those digital ''YOUR SPEED IS" reminders along the highway.I have used those to adjust my VSSB. They are very accurate.
redbird2
08-03-2006, 20:38
I now remember where I read the information on the VSSB in was in the 6.5 book I purchased from Jim go to this link www.thedieselpage.com/65book.htm half way down the page you will see the basic information about this topic.