Bolt Stretch Gauge
Thread Starter
Instructor
Joined: Feb 2005
Posts: 112
Likes: 2
From: Montreal Quebec
Bolt Stretch Gauge
Hi all,
I have a quick question. You guys that are building a motor like a 383 stroker are you all using a bolt stretch gauge when installing rod bolts and other fasteners to measure the length of the bolt after tightening ? Since I don't plan to build a motor every day, I find quite expensive 150$ for this tool for a one shot. I do understand that one of the success of a good motor is to have everything set to the right spec but I was wondering if you had the same results without the tool. I have no problem to spend money on quality part but I do have one to spend money on equipment that will sleep in my garage for year.
I have a quick question. You guys that are building a motor like a 383 stroker are you all using a bolt stretch gauge when installing rod bolts and other fasteners to measure the length of the bolt after tightening ? Since I don't plan to build a motor every day, I find quite expensive 150$ for this tool for a one shot. I do understand that one of the success of a good motor is to have everything set to the right spec but I was wondering if you had the same results without the tool. I have no problem to spend money on quality part but I do have one to spend money on equipment that will sleep in my garage for year.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
A 'bolt stretch gauge' is pretty exotic for every-day use. That's what torque wrenches are for...us 'low-budget' guys [and most US auto manufacturers]. There are all kinds of data charts for selecting the correct torque to apply, depending on the size & type of bolt, the materials of the parts being retained, whether the bolt/nut is lubricated or not, etc., etc. These charts are plenty accurate for general purpose use. Now, if you have a NASCAR engine that is trying to generate 900 hp out of 350 cu. in....normally aspirated and spinning at almost 10K rpm; and you are trying to minimize weight so that you use Grade 8 (or more exotic) fasteners that are smaller than you would normally use; you might want to get the stretch on that bolt to the absolutely perfect place where part retention is maximized. But.... that 3/8"-16 hex-head bolt on my water pump.....it probably doesn't need that gauge to work OK.
