Rake Measurement
Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
You need to measure to reference points that are unaffected by the suspension (i.e., measuring from ground to top of wheel well is n/g). The only place I know of where this would be true is the jacking puck locations - they are directly beneath a common, straight piece of metal (the frame).
Melting Slicks
Joined: Feb 2001
Posts: 2,137
Likes: 1
From: Oklahoma City OK
Cruise-In III Veteran
The answer to your question is the lower A-arms, but that spot is very hard to use without special measuring tools. Most people I know use the metal areas of the frame next the jacking puck holes.
About 1/2-inch difference between the front and rear is a common setting.
About 1/2-inch difference between the front and rear is a common setting.
Team Owner
Joined: Jul 1999
Posts: 50,808
Likes: 10
From: Buy USA products! Check the label! Employ Americans
Originally Posted by FRISKY
The answer to your question is the lower A-arms, but that spot is very hard to use without special measuring tools. Most people I know use the metal areas of the frame next the jacking puck holes.
About 1/2-inch difference between the front and rear is a common setting.
About 1/2-inch difference between the front and rear is a common setting.
The manual tells you to measure at the frame as stated above as I remember.
Safety Car
Joined: Nov 2003
Posts: 4,969
Likes: 2
From: Lake Worth FL
St. Jude Donor '03-'05-'06 & '12
I did a lot of research on this. The definitive answer is that there is supposed to be 5mm of rake measured in front of the front jacking puck hole to behind the rear jacking puck hole.
Racer
Joined: Nov 2004
Posts: 281
Likes: 7
From: Arlington TN.
Originally Posted by dmtnt
I did a lot of research on this. The definitive answer is that there is supposed to be 5mm of rake measured in front of the front jacking puck hole to behind the rear jacking puck hole.
Wow
5mm is not a lot!
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Safety Car
Joined: Nov 2003
Posts: 4,969
Likes: 2
From: Lake Worth FL
St. Jude Donor '03-'05-'06 & '12
Originally Posted by roSSco
Wow 5mm is not a lot!
5mm is not a lot!
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
Originally Posted by roSSco
Wow 5mm is not a lot!
5mm is not a lot!
Premium Supporting Vendor
Joined: Aug 2001
Posts: 5,364
Likes: 38
From: King George VA
Originally Posted by IM QUIKR
5mm is roughly 0.20" If you get somewhere between 1/4 and 1/2 inch front to back difference you'll be fine. Actually you may get a little more down force at speed which would be a good thing. I just swapped my base springs for Z51 and reset the rake at 1/3" diff front to back. After a week of driving I'll re-measure and if it holds, I'll be back in for a final alignment.
I use the location at the frame jacking points as well as it is much easier than the proper spot on the a-arms. I also try to get 1/4-1/2" to help minimize high speed lift.
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Race Director
Joined: Oct 2002
Posts: 16,477
Likes: 26
From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
Originally Posted by Mr. Lucky
You need to measure to reference points that are unaffected by the suspension (i.e., measuring from ground to top of wheel well is n/g). The only place I know of where this would be true is the jacking puck locations - they are directly beneath a common, straight piece of metal (the frame).
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
Originally posted by c5d
Tools Required
J 42854 Trim Height Measurement Gauge
Adjustment
When adjusting rear Trim Height the opposite side Trim Height will be affected.
Vehicle on alignment rack.
Set proper tire air pressure.
Manually lift rear end up approx. 38 mm (1.5").
Gently release & let settle (joust) 3 times.
Measure distance (J 42854) between lowest point of the L/R ball joint (2) and the center of the front of the forward rear lower control arm bushing mounting bolt (1).
Push rear end down approx. 38 mm (1.5').
Gently release & let settle (joust) 3 times.
Measure distance (J 42854) between lowest point of the R/R ball joint (2) and the center of the front of the forward rear lower control arm bushing mounting bolt (1).
Meausre Left and Right sides of vehicle.
True D height is the average of the high and low measurements.
Loosen nut at top of spring bolt.
Adjust D Trim Height by turning the spring bolt (1 turn = 2 mm (5/64").
Jounce 3 times and re-measure.
Tighten spring bolt to 37 ft. lbs.
Measure front spring adjuster bolt gaps (1).
Do NOT exceed maximum (5 mm) difference between right and left rear spring stud heights.
Spec: Front Spring Adjuster Bolt Gap: 18 to 40 mm
J Trim Height
152 mm (5.98 in)
145.6-158.4 mm
5.73-6.24 in
K Trim Height
152 mm (5.98 in)
145.6-158.4 mm
5.73-6.24 in
[CSM, 1997, 3-73]
C'ya
D
Tools Required
J 42854 Trim Height Measurement Gauge
Adjustment
When adjusting rear Trim Height the opposite side Trim Height will be affected.
Vehicle on alignment rack.
Set proper tire air pressure.
Manually lift rear end up approx. 38 mm (1.5").
Gently release & let settle (joust) 3 times.
Measure distance (J 42854) between lowest point of the L/R ball joint (2) and the center of the front of the forward rear lower control arm bushing mounting bolt (1).
Push rear end down approx. 38 mm (1.5').
Gently release & let settle (joust) 3 times.
Measure distance (J 42854) between lowest point of the R/R ball joint (2) and the center of the front of the forward rear lower control arm bushing mounting bolt (1).
Meausre Left and Right sides of vehicle.
True D height is the average of the high and low measurements.
Loosen nut at top of spring bolt.
Adjust D Trim Height by turning the spring bolt (1 turn = 2 mm (5/64").
Jounce 3 times and re-measure.
Tighten spring bolt to 37 ft. lbs.
Measure front spring adjuster bolt gaps (1).
Do NOT exceed maximum (5 mm) difference between right and left rear spring stud heights.
Spec: Front Spring Adjuster Bolt Gap: 18 to 40 mm
J Trim Height
152 mm (5.98 in)
145.6-158.4 mm
5.73-6.24 in
K Trim Height
152 mm (5.98 in)
145.6-158.4 mm
5.73-6.24 in
[CSM, 1997, 3-73]
C'ya
D
These are the points that deterimine the proper rake of the car in the manual.
