Suspension & Brakes Springs | Shocks | Handling | Rotors

Easiest way to measure MM of sway bars

Thread Tools
 
Search this Thread
 
Old 07-28-2009, 03:16 PM
  #1  
TECH Regular
Thread Starter
iTrader: (4)
 
69camaross's Avatar
 
Join Date: Dec 2005
Location: St. Louis, MO
Posts: 456
Likes: 0
Received 0 Likes on 0 Posts
Default Easiest way to measure MM of sway bars

I am looking at purchasing a set of used SLP sway bars and need to have the present owner measure them to make sure they are the SLP 35/21mm bars and not the stock 32/19mm bars. What's the best way to measure these using basic tools as I doubt this owner has a dial caliper?
Old 07-28-2009, 04:23 PM
  #2  
TECH Regular
iTrader: (4)
 
pewter2002's Avatar
 
Join Date: Jul 2009
Posts: 494
Likes: 0
Received 1 Like on 1 Post
Default

For the rear, take an open ended wrench size 19mm and slip it over a straight part of the bar. It should be snug- an 18mm wont slide over a 19mm bar. A vernier caliper is a pain because the jaws shift and converting SAE to metric is not accurate. For the front, use a paper or fabric tape measure and wrap it around your stock 32mm. Compare that with the "new" one- original one will be smaller, but by how much... I dont think a 35mm wrench would be readily avilable to try first method!
Old 07-28-2009, 04:28 PM
  #3  
Banned Village Idiot
iTrader: (36)
 
LS1BLKSS's Avatar
 
Join Date: Aug 2007
Location: Anaheim,CA
Posts: 2,551
Likes: 0
Received 1 Like on 1 Post
Default

open end wrench is your friend!
Old 07-28-2009, 05:53 PM
  #4  
TECH Senior Member
iTrader: (14)
 
mitchntx's Avatar
 
Join Date: Nov 2001
Location: DFW, Texas
Posts: 6,480
Likes: 0
Received 2 Likes on 2 Posts

Default

metric calipers rock!
Old 07-28-2009, 11:28 PM
  #5  
TECH Addict
iTrader: (77)
 
98RedBird's Avatar
 
Join Date: May 2005
Location: Peoria, IL
Posts: 2,772
Received 3 Likes on 3 Posts

Default

I would use a digital caliper. They make life easy, you should really pick one up if you don't already have one!
Old 07-29-2009, 09:12 AM
  #6  
FormerVendor
iTrader: (77)
 
UMI Performance's Avatar
 
Join Date: Apr 2004
Location: Philipsburg, Pa
Posts: 5,473
Received 5 Likes on 3 Posts

Default

If using standard calipers multiple the dimension by 25.4 to get a metric reading.
Old 07-29-2009, 09:15 AM
  #7  
TECH Resident
iTrader: (7)
 
z28mccrory's Avatar
 
Join Date: Jul 2003
Location: Southern Indiana
Posts: 756
Likes: 0
Received 1 Like on 1 Post

Default

Originally Posted by pewter2002
For the rear, take an open ended wrench size 19mm and slip it over a straight part of the bar. It should be snug- an 18mm wont slide over a 19mm bar. A vernier caliper is a pain because the jaws shift and converting SAE to metric is not accurate. For the front, use a paper or fabric tape measure and wrap it around your stock 32mm. Compare that with the "new" one- original one will be smaller, but by how much... I dont think a 35mm wrench would be readily avilable to try first method!
How is SAE to metric not accurate?

Simply multiply the SAE measurement by 25.4
Old 07-29-2009, 11:05 AM
  #8  
12 Second Club
iTrader: (3)
 
spy2520's Avatar
 
Join Date: Feb 2005
Location: Waldorf, MD
Posts: 3,513
Received 0 Likes on 0 Posts

Default

Originally Posted by z28mccrory
How is SAE to metric not accurate?

Simply multiply the SAE measurement by 25.4
should be accurate enough for this.
Old 07-29-2009, 11:49 AM
  #9  
TECH Resident
iTrader: (7)
 
z28mccrory's Avatar
 
Join Date: Jul 2003
Location: Southern Indiana
Posts: 756
Likes: 0
Received 1 Like on 1 Post

Default

Originally Posted by spy2520
should be accurate enough for this.
Its accurate enough for anything, as its an absolute conversion that doesn't round up or down.

I do Cad/Cam work at a woodworking company, and have to do Metric to SAE and vice versa conversions all day long. It sacrifices no accuracy.
Old 07-29-2009, 01:23 PM
  #10  
Launching!
iTrader: (5)
 
csxfbird's Avatar
 
Join Date: Apr 2004
Location: Tucson, AZ
Posts: 227
Likes: 0
Received 0 Likes on 0 Posts

Default

Originally Posted by z28mccrory
Its accurate enough for anything, as its an absolute conversion that doesn't round up or down.

I do Cad/Cam work at a woodworking company, and have to do Metric to SAE and vice versa conversions all day long. It sacrifices no accuracy.
Better yet, just get a digital caliper that can do both. Quells all worries about inaccurate conversions. (I agree with you, by the way, no accuracy is lost with conversions)
Old 07-29-2009, 02:29 PM
  #11  
LS1TECH Sponsor
iTrader: (41)
 
Sam Strano's Avatar
 
Join Date: Apr 2002
Location: Brookville, PA
Posts: 9,581
Received 129 Likes on 84 Posts

Default

Or you could just use an adjustable wrench, tighten it to fit the bar and measure the opening...
__________________
www.stranoparts.com --814-849-3450

18 SCCA National Championships in house, many more for our customers prove we know our stuff.Talk is cheap, results matter.

Check out our KONI prices, our Master Cylinder Brace, and new Xtracker Hub/wheel bearing upgrade kits!
Old 07-29-2009, 03:29 PM
  #12  
TECH Regular
iTrader: (4)
 
pewter2002's Avatar
 
Join Date: Jul 2009
Posts: 494
Likes: 0
Received 1 Like on 1 Post
Default

The digital caliper is definitely the way to go due to the jaws of the vernier caliper opening slightly when removing them to read it. Hence the potential for inaccuracy with my cheap caliper! Someone (SLP?) made a 36.5mm at one point as well.
Old 07-30-2009, 06:08 AM
  #13  
TECH Addict
iTrader: (3)
 
EchoMirage's Avatar
 
Join Date: Oct 2005
Location: SE VA
Posts: 2,255
Likes: 0
Received 0 Likes on 0 Posts

Default

depending on the bushings, it could also very well say the size on the side of them. its probably in SAE, but you can tell which is bigger that way anyway. are you getting bushings with it, or just the bar? can you ask him to give you the old bushings with it, just to see if the size is on it?
Old 07-30-2009, 06:18 AM
  #14  
TECH Enthusiast
iTrader: (8)
 
deelong4002's Avatar
 
Join Date: Jun 2008
Location: Stockbridge, MI
Posts: 724
Likes: 0
Received 0 Likes on 0 Posts

Default

yeah i use 25.4 mm/1inch every single day. It is understood as the absolute conversion. If it's not accurate, my machinists are doing stuff very very wrong then......
Old 07-30-2009, 11:44 AM
  #15  
TECH Addict
iTrader: (4)
 
Mike454SS's Avatar
 
Join Date: Oct 2004
Location: Manchester, CT
Posts: 2,139
Likes: 0
Received 3 Likes on 3 Posts

Default

Originally Posted by spy2520
should be accurate enough for this.
Stop posting and go back to school.
Old 07-30-2009, 11:51 AM
  #16  
TECH Addict
iTrader: (4)
 
Mike454SS's Avatar
 
Join Date: Oct 2004
Location: Manchester, CT
Posts: 2,139
Likes: 0
Received 3 Likes on 3 Posts

Default

Originally Posted by pewter2002
converting SAE to metric is not accurate
you too...stop posting and go back to school
Old 07-30-2009, 02:24 PM
  #17  
TECH Enthusiast
iTrader: (5)
 
00 Trans Ram's Avatar
 
Join Date: Mar 2004
Location: New Orleans, LA
Posts: 556
Likes: 0
Received 0 Likes on 0 Posts

Default

I think the operative statement here is "using basic tools". Calipers and such aren't usually basic. At least, not for me - since I don't have any!

Use a tape measure. Measure the circumference. Here's what you're looking for:

Diameter = Circumference (inches.decimal, inches and fraction)
19mm = 2.349, just larger than 2 5/16
21mm = 2.596, just larger than 2 9/16
32mm = 3.956, just larger than 3 15/16
35mm = 4.327, almost exactly 4 5/16
Old 07-30-2009, 05:22 PM
  #18  
TECH Resident
iTrader: (7)
 
z28mccrory's Avatar
 
Join Date: Jul 2003
Location: Southern Indiana
Posts: 756
Likes: 0
Received 1 Like on 1 Post

Default

I cant believe there is almost a full page of replies about something as simple as measuring a sway bar, lol.

Here is an idea... go to a local Napa and ask them if you can use a set of calipers for a second. They use them to measure seals and bearings when the part numbers aren't legible... so they have a pair under the counter.
Old 07-30-2009, 09:05 PM
  #19  
TECH Regular
iTrader: (4)
 
pewter2002's Avatar
 
Join Date: Jul 2009
Posts: 494
Likes: 0
Received 1 Like on 1 Post
Default

Originally Posted by Mike454SS
you too...stop posting and go back to school
Wow, one poorly written statement and I've got tech enthusiasts, machinists and a passive/aggresive cyber bully jumping all over a partial statement. I should def watch what I post more carefully like Mike454SS (Massachussets plates) does! You know, asking people where to get tint locally, duh!, POSTS ON WHERE TO GET REAR ANTI RATTLE CLIPS THEN ANSWERING YOUR OWN POST... I guess you are quite the details man, but as long as the repairs to your wrecked (twice!!!) 2000 pewter Camaro LOOK good, you're happy. Perhaps some DRIVING SCHOOL is in order for you! Oh yeah, the douchebag that door -dinged you, a real careless jerk! What happened after was classic passive/aggressive- minimal confrontation at the time- then lay into him on a forum - real hubris haha! Classic bully too, no real, in your face confrontation, just putting him in his place on the net- pathetic. Your contribution to THIS thread was nil, it's just your M.O. To everybody thanks for the correction, to Mike454SS, waiting to catch YOUR next marvellous post(959 and counting). If it is of interest, most will try to reply/help. If it isn't they will probably move on to the next one without comment...
Old 08-01-2009, 01:25 AM
  #20  
TECH Addict
iTrader: (4)
 
Mike454SS's Avatar
 
Join Date: Oct 2004
Location: Manchester, CT
Posts: 2,139
Likes: 0
Received 3 Likes on 3 Posts

Default

You know, you're right, I was rude...but please be sure about your "Facts" before you post them. 1 inch is EXACTLY 25.4 mm, so that conversion leaves absolutely no margin of error, and is very straightforward with a calculator.

I'm not going to bother to reply to the rest of your message, it's FAR more uncalled for than anything I said to you.

Last edited by Mike454SS; 08-01-2009 at 01:41 AM. Reason: spelling error




All times are GMT -5. The time now is 05:22 AM.