The strap is surface ground and machined from 1″ square 4140 alloy steel, a very strong and heavy steel. The mating surface and the top surface are surface ground to be extremely flat and parallel to each other. My test indicator, which measures to .0001″, shows no variation at all.
The first two pictures show the two machined sides. The third and fourth pictures show the machined surfaces protected by a rust preventive wax which can be easily removed by a solvent. The strap includes two grade eight bolts of the proper length as shown in the last picture. The center main cap pictured is not included.
A center main bearing strap provides strength and rigidity to the center main bearing of our little three main bearing engines. Most how to books on increasing the performance suggest adding a surface ground strap.
If you are going to run your engine hard, high rpms, racing, auto crossing or other competition activities, you need one of these to help your engine to last.
Others offer straps also but they are not surface ground and appear to be made from 1/2″ by 1″ steel with no indication of what kind of metal it is.
I have used these straps on all of my race engines for the past eight years with no bearing issues even though I rev to 8,000 rpm.
You must have your center main cap machined or surface ground flat down to the bolt hole surface. You can have that done at your local machine shop or I can machine/surface grind it for you. Send me a message if you are interested in my doing the work, and I will send you the details.
After you have the center main cap machined/surface ground flat, installation is a simple bolt in process.
Follow the torque guidelines for the stock center main cap. You will have to bend slightly the forward mounting tab for the oil pickup assembly. The strap has a 1/4″ hole threaded for the fine thread bolt holding the mounting tab. The straps offered by others appear to not have the 1/4″ threaded hole.
This strap fits all 1275 inline engines.
Please send me a message if you want one for a 948 or 1098 engine. I can machine one in about a week. Same price.