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how to: correct pinion angle

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we are all hotrod entuisiast. in our endeavors to obtain maximum suspension and vibe-less operation we go through great lengths. Most make adjustments shooting in a barrel :facepal:... so here we go..

noting marks with stock REAR upper control arms will get you a base measurement but very inaccurate measurement.

*load suspension on a drive on lift or Leveled drive-on ramps. chock wheels.

*obtain a pinion angle finder and notepad.


*from the image above, you put the angle finder on the tailshaft of the transmission. Write down your measurement.

it should be in positive Degrees.

*At the rear of the car: set angle leveler on the pinion flange. record the measurement. it should be positive or negative.


Note: "hypothetical" +2*(trans) + 0*(pinion flange) would equate Good results for pinion angle at +2. +2 or +1 is ideal. suspension movement will vary will in motion but not exceed those measurements.

the driveshaft should transition well around +1*


-shimming the transmission mount with washers will aid in finding the correct angle.

-on a mustang and 4-link, obtaining the correct measurements will be adjusted from adjustable upper control arms.

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i wonder how crappy my pinion angle is when i drive aired out :( dif nose is prolly straight down and driveshaft straight up. pay to play i guess

- - - Updated - - -

actually it's prolly the other way around haha!

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AWESOME THREAD thank you seriously! It is surprisingly hard to find info like this with pictures. It makes it so hard to understand what you are reading.

Only thing I noticed, you have to have your driveshaft off to do this? It looks like its off in your pics but I'm a blonde when it comes to looking at a pic that doesn't show the entire area lol. I just can't imagine the rest of it lol.

Oh and I've always heard that +3 is acceptable??

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I done mine with driveshaft in. However i have a tko-600 and there was a flat portion on the tailshaft. I have a steeda spacer on the pinion. It had enough material to lay flat without movement. If i didnt have that advantage i would have removed driveshaft.

Sent by smoke signals

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I either read this post way too fast, or the information is not conveyed properly.

The whole point behind setting pinion angle (for drag racing) is so your driveline will form a generally straight line or at a minimum, will have equal angles at both ends of the driveshaft during operation.

Measuring from the end of the tail shaft is not always the most accurate method. I prefer to measure from the front of the harmonic balancer. Let's say that hypothetically, my crank centerline runs at a +6* angle.

Different suspension components will behave better with certain pinion angle ranges. For example. Soft stock bushings are better suited ~3* negative from the crank centerline angle (CCLA). Hard poly bushings are usually best around -2.5 to -2 degrees from CCLA. Solid bushings do better around -1.5 to -1 degrees from CCLA.

The reason for this is that under acceleration the pinion will try to rotate upward and these settings will get you a very neutral pinion to CCLA.

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MK i would agree to the Crank method if you were using a 1-speed gear box affixed to a straight driveshaft without yokes. Meaning no flex or movement. K-member and trans x-mount dictates the angle. Mine for instance: TKO-600 with stiffler's Mount is +1 angle on trans. 0 degrees at pinion flange. I have Solid Bushings except chassis side of LCAs(harsh slightly). however, transition from point A to B means i have a .5* to 1* pinion angle. i tell you what, its silky smooth driving after 75MPH . i have previously used 2* and 3* and it was not a good vibration.

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So according to Baselines site, since my LCA's are polyurethane on both sides, and my uppers are solid on the body side and rubber on the housing, I should be running a 2* pinion angle?

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