anyone now lengths for the headbolts
There is not a simple answer to your question.
B&S used at least 2 different lengths on your 7hp engine. ....Three (3) longer bolts are 2-21/32" long, and are used in the corner of the head around the exhaust valve. ....The shorter bolts are 2-5/16" long, and are used for the other head bolts.
What complicates the issue, is if the gas tank, brackets, or other accessories are fastened to the engine under the heads bolts, longer bolts or special studs were used. ...Sometimes spacers were used to gain height to clear the fins on the head, so extra-long bolts were used.
The B&S parts manual for your model & TYPE number would specify what head bolts your engine originally had. ....There is a parts manual in the Manuals Forum : http://gardentractor...70400-to170466/ but I can not get the file to open for me. ....Maybe you'll have better luck?