Date sent: Wed, 12 Apr 2000 13:37:23 -0500 (CDT) From: Jon Pace Subject: [80] Adjusting LSPV body after lift. To: 80_series@sgiblab.sgi.com Send reply to: 80_series@sgiblab.sgi.com Spent some time under the truck last night trying to figure out if there is an easy way to know how much you could lower the LSPV body to adjust the braking pressure after a lift. Basically, moving the end of the rod (the normal point) moves a rod 600 mm long. The point on the rod where the LSPV actually contacts is only 38 mm from the pivot. End result is that the movement at the end of the rod is 1/15.75 of the movement at the body. So, if you've lifted your truck 75mm (after allowing for settling, etc.), you'd need to lower the LSPV body by 4.8mm to be in the right ballpark. You can adjust the end of the rod roughly +/- 6mm, so you'd need to get the LSPV body withing +/- 0.38mm to be able to make the final adjustment with the end of the rod. I hope that helps someone who's going to do the lift. I wish I had thought about it before I moved everything around and lost a starting reference point. Christo, maybe add this to the FAQ. Juice From: "Willem-Jan Markerink" To: 80_series@sgiblab.sgi.com Date sent: Mon, 17 Apr 2000 17:21:48 +0100 Subject: Re: [80] Adjusting LSPV body after lift. Send reply to: 80_series@sgiblab.sgi.com On 12 Apr 00 at 13:37, Jon Pace wrote: > Spent some time under the truck last night trying to figure out > if there is an easy way to know how much you could lower the LSPV body > to adjust the braking pressure after a lift. Basically, moving the > end of the rod (the normal point) moves a rod 600 mm long. The point > on the rod where the LSPV actually contacts is only 38 mm from the > pivot. End result is that the movement at the end of the rod is > 1/15.75 of the movement at the body. > > So, if you've lifted your truck 75mm (after allowing for settling, > etc.), you'd need to lower the LSPV body by 4.8mm to be in the right > ballpark. You can adjust the end of the rod roughly +/- 6mm, so you'd > need to get the LSPV body withing +/- 0.38mm to be able to make the > final adjustment with the end of the rod. > > I hope that helps someone who's going to do the lift. I wish I had > thought about it before I moved everything around and lost a starting > reference point. > > Christo, maybe add this to the FAQ. Haven't checked on the 80, but on the 60 it was simply a matter of lifting the axle-mounted part by screwing it onto two bolts (with a bunch of nuts on both sides), which also makes it instantly adjustable. The only reference needed in that case is the amount of lift.... -- Bye, Willem-Jan Markerink The desire to understand is sometimes far less intelligent than the inability to understand [note: 'a-one' & 'en-el'!] Date sent: Mon, 17 Apr 2000 13:05:34 -0500 (CDT) From: Jon Pace Subject: Re: [80] Adjusting LSPV body after lift. To: 80_series@sgiblab.sgi.com Send reply to: 80_series@sgiblab.sgi.com > > Haven't checked on the 80, but on the 60 it was simply a matter of > lifting the axle-mounted part by screwing it onto two bolts (with a > bunch of nuts on both sides), which also makes it instantly > adjustable. The only reference needed in that case is the amount > of lift.... > Yes, that can be done, and I did it to begin with... but after having the rod (adjusting bolt to LSPV body) hitting the trailing arm and trying to bend - then finding the now-higher adjusting bolt had also been thrown up high enough (3") to rip open my extended diff breathers, I decided it wasn't a very good option when adjustment of the LSPV body is easy, and actually called for in the manual. Your truck may not have those problems, Juice