Beef Master, Welcome to your SV Community Forum.
Excuse my bluntness. You should not be serving the public without attaining a high degree of culinary competency and food safety knowledge. You could be exposing your customers to serious health risks. A 4" thick piece of meat will not be completely cooked at 135ᴼF in 3 hours
Please stop what you are currently doing, take John’s advice, and using Baldwin’s tables replan your sandwich beef production technique.
Fundamental elements of successful restaurant operation include attention to details and equipment use knowledge. You need to acquire more of both and i want to help you.
You are experiencing difficulty finding advice for SV cooking 4" thick cuts of beef because it’s not recommended. Please refer to Baldwin.
You might consider breaking down the beef into 3-inch thick pieces along seams in the muscle group whenever possible. All pieces should be of the same thickness. Lengths don’t matter as long as the pieces fit in your cooking vessel. Remove any visible connective tissue to improve your guests’ eating experience. You can get the same size slices as before by thinly slicing the 3" thick beef on the bias.
If you don’t want to vacuum seal your meat be sure to use the high quality large or extra-large Zip-Loc Freezer Bags. Storage bag seals are unreliable for cooking. Many commercial SV cooks use large Cambro storage containers or convert insulated cooler chests for SV cooking. Both are approved for foodservice use. The Coleman 48-can Party Stackers are particularly successful. There are ample details with pics here in your Forum.
Quality is always what your guests say it is. How tender do they like their beef? I recommend discovering optimum tenderness by cooking four or more 3’ thick pieces of meat together at 131ᴼF (Medium-Rare) and sequentially removing single pieces at 6 hour intervals. Before cooking identify each piece by writing the numbers 6 - 12 - 18 - 24 - 30, - and so on with a wide permanent marker to identify cooking times for each respective piece. Remove each piece and ice bath chill ( see Baldwin ) and refrigerate each test piece. When ready to evaluate get some helpers to assist you in taste testing each sample and arriving at a consensus of the ideal doneness and its associated cooking time. A few willing frequent customers participating would be useful. You supply the beer.
I suggest to avoid waste you can repack and cook the 6 and 12 hour pieces to completion. Be sure to re-label them for consistency.
I have posted here many times on advance SV cooking techniques for foodservices. You might find some useful ideas by following my past contributions.
Please advise us on the outcome of your tests to provide guidance to others. Thank you.
Stay safe and keep well.