Pinion angle

littlemanjoe · 08-23-2021, 11:57 PM

Seting the pinion angle in a leaf spring stocker running CalTracs. I know Calvert wants the pinion yoke down 2 to 4 degrees.
What should the operating angle of the transmission to driveshaft be?

garyc · 08-24-2021, 03:44 PM

really not adjustable, all depends on height of pinion, should be "0" when pinion goes up under load??

Mark Yacavone · 08-24-2021, 05:22 PM

Ideally, it should be the inverse of the lower angle, but if you haven't moved anything around in a Camaro, it should be fine.

FireSale · 08-25-2021, 02:23 PM

Pinion angle and Caltracs has always confused me. A negative pinion angle is meant to negate axle/spring wrap under hard load, but the purpose of Caltracs is to prevent that. If you have a negative 4 degree pinion angle with Caltracs, it will remain negative 4 under load with the exception of the dime thickness racers leave as slack up front.

If I'm right, pinion angle is the relationship between the centerline of the crankshaft and the centerline of the pinion gear. It should be 0 (parallel) under load. A "nose down" pinion could wrap up to parallel with stock suspension but not with Caltracks.

Mike Rietow · 08-28-2021, 08:55 PM

Quote:

Originally Posted by FireSale

Pinion angle and Caltracs has always confused me. A negative pinion angle is meant to negate axle/spring wrap under hard load, but the purpose of Caltracs is to prevent that. If you have a negative 4 degree pinion angle with Caltracs, it will remain negative 4 under load with the exception of the dime thickness racers leave as slack up front.

If I'm right, pinion angle is the relationship between the centerline of the crankshaft and the centerline of the pinion gear. It should be 0 (parallel) under load. A "nose down" pinion could wrap up to parallel with stock suspension but not with Caltracks.

Deflection at the drop is being accounted for. Down, with the damper fixed to the back side of the rearend gets the shaft of the damper exiting the main body of the shock/damper, which is correct also.

rod · 08-29-2021, 04:04 PM

the ? remains, except for you guys with mega $$ and a go pro camera mounted under the car to view movement...how do you know what the pinion is really doing. every car is different even if it is the same car [1 67 Camaro next to a duplicate 67 Camaro]
just because 1 guy says 4 degrees down tells you absolutely nothing. so the pinion is 4 degrees down, down from what, the ground?
the difference is between the pinion and the driveshaft. if the pinion is 4 down and the shaft is 4 down, then you have 8 degrees. [and y7ou could still have 0 to 1 degrees at the tailshaft] loss of hp, and a broken U-Joint in your future.
spring packs are different in stiffness. spring pads are different [most only a bit longer than housing dia. and therefore, offer very little resistance to movement]. shock position [front or rear of axle] shock stiffness [front or rear], tire size and width, tire pressure, launch RPM and launch hp,track traction and probably several more things cause pinion angle to change at launch. and how long will it stay.
all in all, be careful about making general statement about someone elses pinion angle.
Rod in AZ

JGrossijr · 09-08-2021, 09:24 AM

Driveshaft/pinion operating angles explained and illustrated.
https://markwilliams.com/driveshafttech.html

08-23-2021, 11:57 PM	#1
littlemanjoe Member Join Date: Feb 2018 Location: West Layfayette Posts: 125 Likes: 195 Liked 75 Times in 28 Posts	Pinion angle Seting the pinion angle in a leaf spring stocker running CalTracs. I know Calvert wants the pinion yoke down 2 to 4 degrees. What should the operating angle of the transmission to driveshaft be?

08-24-2021, 03:44 PM	#2
garyc Member Join Date: Mar 2021 Posts: 124 Likes: 0 Liked 51 Times in 30 Posts	Re: Pinion angle really not adjustable, all depends on height of pinion, should be "0" when pinion goes up under load??

08-24-2021, 05:22 PM	#3
Mark Yacavone Veteran Member Join Date: Mar 2002 Location: Miles From Nowhere Posts: 7,742 Likes: 2,843 Liked 5,001 Times in 1,901 Posts	Re: Pinion angle Ideally, it should be the inverse of the lower angle, but if you haven't moved anything around in a Camaro, it should be fine. __________________ "We are lucky we don't get as much Government as we pay for." Will Rogers

08-25-2021, 02:23 PM	#4
FireSale VIP Member Join Date: Feb 2014 Location: Lakewood Washington Posts: 1,407 Likes: 29 Liked 237 Times in 126 Posts	Re: Pinion angle Pinion angle and Caltracs has always confused me. A negative pinion angle is meant to negate axle/spring wrap under hard load, but the purpose of Caltracs is to prevent that. If you have a negative 4 degree pinion angle with Caltracs, it will remain negative 4 under load with the exception of the dime thickness racers leave as slack up front. If I'm right, pinion angle is the relationship between the centerline of the crankshaft and the centerline of the pinion gear. It should be 0 (parallel) under load. A "nose down" pinion could wrap up to parallel with stock suspension but not with Caltracks. __________________ Dale Shearon 68 Mustang 6394

08-29-2021, 04:04 PM	#6
rod Member Join Date: Dec 2009 Location: Kingman, NW AZ. in the middle of the longest stretch of Route 66 Posts: 313 Likes: 0 Liked 20 Times in 15 Posts	Re: Pinion angle the ? remains, except for you guys with mega $$ and a go pro camera mounted under the car to view movement...how do you know what the pinion is really doing. every car is different even if it is the same car [1 67 Camaro next to a duplicate 67 Camaro] just because 1 guy says 4 degrees down tells you absolutely nothing. so the pinion is 4 degrees down, down from what, the ground? the difference is between the pinion and the driveshaft. if the pinion is 4 down and the shaft is 4 down, then you have 8 degrees. [and y7ou could still have 0 to 1 degrees at the tailshaft] loss of hp, and a broken U-Joint in your future. spring packs are different in stiffness. spring pads are different [most only a bit longer than housing dia. and therefore, offer very little resistance to movement]. shock position [front or rear of axle] shock stiffness [front or rear], tire size and width, tire pressure, launch RPM and launch hp,track traction and probably several more things cause pinion angle to change at launch. and how long will it stay. all in all, be careful about making general statement about someone elses pinion angle. Rod in AZ

09-08-2021, 09:24 AM	#7
JGrossijr Junior Member Join Date: Nov 2001 Location: Brentwood, California Posts: 96 Likes: 340 Liked 424 Times in 57 Posts	Re: Pinion angle Driveshaft/pinion operating angles explained and illustrated. https://markwilliams.com/driveshafttech.html