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8mm Extra Long Allen Socket

Sir Tool P243
8mm Extra Long Allen Socket
Solid one piece construction needed for busting loose rusted bolts of heat exchangers/exhaust systems.
The extra long length easily accesses these hard to reach exhaust system bolts. 3/8" drive.
Applicable: Porsche model 911, 930.

http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search.cgi?command=show_part_page&please_wait= N&make=POR&model=TOOL&section=WTD026&page=123&book mark=7&part_number=PEL-TOL-P243

Yes the ones you are accessing through the holes in the heat exchangers are.

What Zippy said. The access holes through exchangers lead to what are called Barrel Nuts. 8mm Allen.

The rest are either 12mm or 13mm steel or copper lock nuts.

If you have a set of long Allen wrenches you can use the 8mm long end through the exchanger and just do the "linked wrench" trick with say a 19mm box end wrench on the short arm for leverage.

Cooper