View Full Version : Pinion Angle please help


Chad00ws6
10-19-2002, 06:16 PM
I just installed my Spohn Torque arm. I'm not great with angles but here goes. My driveshaft if you are looking at the anglefinder from the driver's side of the car is 2 degrees to the left side of Zero (driveshaft sloping towards rear of car). The rear end is almost 5 degrees to the right side of zero(sloping towards the front of the car). My question is this which side is negative? the left side is what I think. So I need to rotate the rear to be higher on the other side (4degrees to the left) correct? That would give me a total pinion angle of -2 right? Sorry this may sound confusing but I am very confused right now.

Gold Phoenix
10-19-2002, 06:37 PM
This is how I made sure I got the right down angle. I moved the TA until the pinion and the DS are the same angle. Then I adjusted the pinion angle down until I got my desired setting. Also. have weight on the wheel to get the right angle on the ground

Chad00ws6
10-19-2002, 07:52 PM
TTT

dand35th
10-19-2002, 08:38 PM
if you adjust til the DS is 0 then the rear will be around 2 or 3 , angling down from the DS which I believe is the neg. 2 or 3 you should have.

Lar's SS
10-21-2002, 11:20 AM
Chad,

Neg. angle is pinion pointing down. With what you discribed above, DS at 2 and the pinion/rear at -5 (pointing down) your at -3 now. Adjust the pinion up, checking both sides until they are in the range you want. The DS will move or change too, that's why you need to go back and forward until the difference is -2 to -3. I run -2.5.
Remember, it's the total angle, not just the pinion angle.

Steve Burger
10-21-2002, 02:40 PM
I agree that you add. One is a negative number and one is a positive number. Add the two together and you get -3. The DS will slope down as the tailshaft of the trans is not in line with the pinion. It never will be. The DS is just the long edge of a right triangle, and serves as a reference point only.

Think abour it. Our cars come from the factory with zero deg of pinion angle on the stock TA. With the DS sloping down by nature, you could never get a pinion angle that would be zero without a negative number. You would always have the DS angle that is not zero plus some other number.

This is the way I have seen this done ad what BMR explained when I bought the adjustable TA.

The other way I have set this is to use my subframe connectors to find zero degrees. Using the subframes takes out the element of "is the car 100% level". Then set the pinion 2 deg down rrom that number. Comes out the same.

<small>[ October 21, 2002, 02:42 PM: Message edited by: Steve Burger ]</small>

dand35th
10-21-2002, 07:29 PM
the problem is , is that your not putting the rear in realtion to the car...your ARE putting it in relation to the driveshaft!!

from the passenger side measure you want the needle to the left 2 deg. of the drveshaft.

from the drivers side , you want the needle 2 deg. to the right of the driveshaft angle.

Chad00ws6
10-21-2002, 09:01 PM
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif"> Originally posted by dand35th:

from the passenger side measure you want the needle to the left 2 deg. of the drveshaft.

from the drivers side , you want the needle 2 deg. to the right of the driveshaft angle. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Finally someone said it where it is very easy even for me. Yes it was about seven degrees to the right of the other number from the driver's side. I did adjust it and for now I have it on the same as the other number since I was'nt exactly sure which way to go. I will adjust it soon.

By the way will me having -2degrees pinion angle help me get better traction off of the line? with it set at zero I was still spinning my ET streets yesterday.

dand35th
10-21-2002, 10:03 PM
That? you can give ME the answer...! I just put one in myself and have yet to mess with it. Let me know how it works out changing angles.

Chad00ws6
10-22-2002, 12:00 AM
The DS was sloping towards the rear of the car and was 2 degrees to the left of zero. The rear was sloping towards the front of the car and was 5 degrees to the right of zero. The DS was -2 correct. How could they both be negative if they are sloping towards opposite ends of the vehicle? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

I guess I just dont understand how they can both be negative if they are on the opposite sides of zero. I don't know I will keep adjusting I guess.

<small>[ October 21, 2002, 12:01 PM: Message edited by: Chad00ws6 ]</small>

Colonel
10-22-2002, 12:15 AM
I think ya'll are getting yourselves <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />

The DS sloping downwards towards the rear by 5 degrees (That's ALOT if that's correct!) and the pinion sloping downwards towards the front by 2 degrees total together to make -7 degrees of pinion angle (the pinion angle is the difference in the angle between the DS and itself which is what is confusing ya'll. You're taking "difference" to mean subtract the 5 from the 2 or the 2 from the 5, etc... That's not right. You simply add the difference of each from horizontal together to get the difference between DS angle and pinion angle. In this case we have 2 and 5 = -7 degrees which is WAAAAAAAAY too much if this was measured accurately. Shoot for -1 to -2.5, IMO.

As mentioned before, these measurements should be taken ONLY with the car level and with normal driving weight being supported by the rearend.

<small>[ October 21, 2002, 12:23 PM: Message edited by: Colonel ]</small>

Steve Burger
10-22-2002, 12:42 AM
The drive shaft is the Positive angle, or +2. The Pinion is the negative angle or -5. Add the two together and yu have the total angle or -3. I would get rid of .5 - 1 total degree of negative angle. In other words lengthen the bottom adjuxtment bolt to take out the unwanted angle. I run -2 deg all the time.

dand35th
10-22-2002, 12:58 AM
not right 2,1,0,-1,-2,-3,-4,-5
that is 7 difference......look at what the coloner says and what I did before.

DrkPhx
10-22-2002, 02:17 AM
I also come up with -3 total degrees. I use the same method that Steve does. This is also recommended by Spohn and is the standard method to measure pinion angle that custom rodders use. If I'm missing something, please let me know. I've had the Spohn TA for 2 years and run -2 for street and strip.

dand35th
10-22-2002, 09:58 AM
you guys are thinking waaayy to much....you want the difference in angle degrees....from the 2 to left of zero and 5 to right of zero is a TOTAL of 7 degree change NOT 3!!!!!

again
2 1 0 1 2 3 4 5
there are 7 spaces there = 7 degrees or a difference of 7.. however you want to see it, it will always be a difference of 7!!

Steve Burger
10-22-2002, 09:58 AM
Negative pinion angle will help stop the spinning. Too much negative pinion angle will eat U Joints. A positive pinion angle will make it easier to spin.

Here is the reason. Zero deg of Pinion angle is optimum for acceleration. But power tends to take the path of least resistance. If you think about it the easiest thing for the pinion to do is walk up the ring gear under power. The next easiest thing is for the pinion to twist the rear end or plant the passenger side tire harder. Under light acceleration this is minimal and that is why the zero deg pinion angle from the factory. Under very hard acceleration like in drag racing, a negative pinion angle will allow the pinion to walk a little and get back to around zero. Too much negative pinion angle will place the pinion out of phase with the rest of the power train at any acceleration rate and bind the U joint.

I run -2 on the street and -2 to -3 at the track.

I hope this helps.

Reckless
10-22-2002, 01:13 PM
Check my post regarding this subject <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />

<small>[ October 22, 2002, 01:13 PM: Message edited by: Reckless ]</small>

Lar's SS
10-24-2002, 09:59 AM
Carcraft this month Dec 02. More on this Never ending Topic.