Guest Posted March 11, 2002 Share Posted March 11, 2002 My problem is I'm freshing up my 350 for the 02 season, and last year I had the rods reconditioned, well I guess my local machine shop did not replace the bolts and on putting the engine back together a few of them started twisting. Is there an easy way to replace bolts while the engines assembled. I've already purchased ARP wave bolts,and really dont want to remove the heads again. My car 72 that runs 12:80 ET's Thanks for keeping the Monte' alive!!!! Link to comment Share on other sites More sharing options...
wallaby Posted March 11, 2002 Share Posted March 11, 2002 I think that when new rod bolts are pressed into the rods, the rods need to be resized. Link to comment Share on other sites More sharing options...
Guest Posted March 11, 2002 Share Posted March 11, 2002 The rods do need to recon'ed after the bolts are changed. the shape of the bearing bore will change with the amount of clamp load the bolts produce. thats why they have to be redone after a bolt change. Don Link to comment Share on other sites More sharing options...
Guest Posted March 11, 2002 Share Posted March 11, 2002 You should also have your rods shotpeaned for added strength. Link to comment Share on other sites More sharing options...
Guest Posted March 13, 2002 Share Posted March 13, 2002 OK, learning curve here. I'm not trying to be optomistic but.... how would new rod bolts affect the bore shape of the rod? Is it because the bolt may be a different diameter? Jon. Link to comment Share on other sites More sharing options...
Guest Posted March 13, 2002 Share Posted March 13, 2002 The clamp load is different for say ARP bolts vs stock GM bolts? I That they are slightly higher on headbolts. Jon. Link to comment Share on other sites More sharing options...
Guest Posted March 13, 2002 Share Posted March 13, 2002 1 Yes the clamp load on an arp is higher, thats why they are stronger. any time you compress metal it attempts to "flow" away from the "load", change the load = change the amount of "flow". so if the metal is flowing more then the bore dia will be effected. couldn't think of a better way to explain it. Don Link to comment Share on other sites More sharing options...
wallaby Posted March 13, 2002 Share Posted March 13, 2002 When the rod bolts press in, they slightly disfigure the rod. ( basicly the hole in the rod expands when you force the bolt through it) The rod area around the bolt is now deformed, and makes for an irregular surface for the bearings to rest against. Resizing the rods involves taking a couple of thousanths away from the rod ends where they meet with the rods, Then bolting them to the rods, torqueing them down, and boring/honing them perfectly round again. Bolt tightness can be measured in torque, or by bolt stretch. Stretch measurement is the more accurate method. Either way,the goal is to tighten the fastener enough so that it stretches slightly, so as to hold a constant preload on the parts to be joined. ( same thing with head bolts, lug nuts, etc.) Waveloc bolts are stronger, and resist stretching. In order to get the same stretch from a waveloc bolt, it will need to be tightened further. Link to comment Share on other sites More sharing options...
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