The 258 came with 998 around '78 (they kept snapping rear bands in the 904s, which is the beef up in the 998) The converters are different for lockup and non-lockup 727. Same for 904 (4 cyl version lockup was a 909) and the 998 only had lockup converter afaik (the trans was made capable of either lockup or non-lockup) The 999 has a stronger converter than the 998. (I snapped several 998 converters in my Eagles while towing) New replacements are all oven brazed and thicker, stronger metal than original. The lockup clutches were improved as well. (aftermarket has taken this even further) Not all AMC flexplates have both 727 and 99X holes, but many do. Jim Blair, Lynnwood, WA '87 Comanche, '83 Jeep J10, '84 Jeep J10 From: Todd Tomason <jayscore@xxxxxxxxxxxxx> Subject: Re: [AMC-list] Need flexplate application help To: msproviero@xxxxxxxxxxx, "AMC, Rambler, Nash, Jeep and family" <amc-list@xxxxxxxxxxxx> Message-ID: <5737EA6E6E2D40768DA53BF8E8A1FE13@JETHRO> Content-Type: text/plain; format=flowed; charset=iso-8859-1; reply-type=original In general, the 360 and 401 used the 727, the 304 used the 998, and the 258 used the 904. The flexplate is balanced to the engine. When my son broke a piston in the 360 in his 78 Matador, we swapped in a 304 out of a 73 Javelin. We had no problem mating the 304 up to the 727. The 304 flexplate already had holes drilled for both the 998 and the 727. My guess is that the unbalanced flexplates were the same for all the engines, and therefore had the holes for both transmission sizes. The appropriate weights were then welded on to balance it for each engine size. AFAIK, the torque converter is specific to each transmission. Todd _________________________________________________________________ Windows Live™ SkyDrive™: Get 25 GB of free online storage. http://windowslive.com/online/skydrive?ocid=TXT_TAGLM_WL_skydrive_042009 -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://list.amc-list.com/pipermail/amc-list-amc-list.com/attachments/20090429/5f607b38/attachment.htm> _______________________________________________ AMC-list mailing list AMC-list@xxxxxxxxxxxx http://list.amc-list.com/listinfo.cgi/amc-list-amc-list.com