2/4" drop questions?
#11
TECH Veteran
iTrader: (5)
You use a 360* angle finder with a magnetic base (sounds expensive but it isn't, you can get it at Sears, carpenters use them)....I haven't done this in a long time, but from what I remember, you attach the angle finder to the driveshaft and record the reading, then remove the driveshaft and put the angle finder on the face of the pinion yoke and record that reading, then find the difference in the two and adjust accordingly.
On different applications (such as drag racing), I've heard of guys adjusting their pinion angles to compensate for the torque that moves the rear end, but...I *think* that the pinion angle should be around -2 or -3* for most applications, but I'm not 100% sure. Hopefully someone who definitely knows can chime in. I do know that you want your pinion angle to be at 0 when the vehicle is under power
On different applications (such as drag racing), I've heard of guys adjusting their pinion angles to compensate for the torque that moves the rear end, but...I *think* that the pinion angle should be around -2 or -3* for most applications, but I'm not 100% sure. Hopefully someone who definitely knows can chime in. I do know that you want your pinion angle to be at 0 when the vehicle is under power
ladder bars get -2 to -4 degrees
leaf springs can have as much as -6 or -8
The whole idea is stay as close to 0 as possible without ever ending up with positive pinion angle under acceleration (thus why I call it "pre-load"). This is all about how much deflection you get in the suspension components. 4 links get very little so they don't require much "pre-load" vs leaf springs bend all over the place so they need lots.
Flip side of the issue. Anything other than 0 causes u-joint wear, loss of HP, and vibration.
Most people I don't think have a clue what their pinion angle is (I didn't bother with it when I had leaf springs). They just run the vehicle however it is and only adjust if there is vibration (even then they don't "set" the pinion angle, they just toss some shims in till things smooth out).
Last edited by 2001CamaroGuy; 01-05-2010 at 09:50 AM.
#12
PT's Slowest Truck
iTrader: (19)
Most people I don't think have a clue what their pinion angle is (I didn't bother with it when I had leaf springs). They just run the vehicle however it is and only adjust if there is vibration (even then they don't "set" the pinion angle, they just toss some shims in till things smooth out).
#13
TECH Veteran
iTrader: (5)
Here is a quick write up:
http://www.carcraft.com/howto/91758/index.html
I'm not sure I agree on his ladder bar and 4 link numbers (I have it from some reliable sources that 4 link is stiffer). But the leaf spring stuff is right where I have always been told. Happy reading... Google is your friend
http://www.carcraft.com/howto/91758/index.html
I'm not sure I agree on his ladder bar and 4 link numbers (I have it from some reliable sources that 4 link is stiffer). But the leaf spring stuff is right where I have always been told. Happy reading... Google is your friend
#14
On The Tree
Join Date: Jan 2010
Location: Garden Grove,Ca
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I had an 06 sierra crew and did the belltech springs and flip for a 2/4 drop and I definetly wished I had gotten the spindles.My current 07 new body style has a 3/5 mcgaupheys drop done by Traders Trucks here in Cali and they warned me about doing springs only but I was cheap and didnt listen.I would do a c notch in the rear if you can ,I didnt on my 06 and I regret it.I would stay away from DJM stuff,I deal with Traders alot(I go to lunch with the techs that work there all the time)and theyare the only ones I let work on my truck,and they say DJM pretty much sucks.There's a reason Mcgaupheys won an award from GM for their spindles.
Last edited by Shane B; 01-13-2010 at 07:32 PM.
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