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Discussion Starter #1 (Edited)
This is kinda an opinion poll, because I know the right answer; 'don't use a torque wrench, use a stretch gauge...'

Start with the story. Bought a rebuilt roller 302 motor from a friend, zero miles, older Trick Flow TW heads that were just rebuilt, new everything and bolted back on with new ARP bolts. New 1.7 roller rockers, new B303 cam. He's a good wrench and he bought the stock rebuilt short block, and to keep the builder honest he tore it back down and verified the bearing, piston-wall clearances, ring end gaps and so forth. Then he changed his mind, wants way more drag-power in his '67 and sold it to me for $2,000. I can't do any better than that for my low budget street-or-track '68 coupe can I?

Well, maybe? How about the nice Canton 8 qt pan with kick-out baffles? Done. How about the Canton windage tray, designed to fit the pan? Only a few bucks. Done. Well, it bolts onto the Canton main girdle, which comes with special ARP main bolts. Well.... ok cool. One thing left, how about some ARP Pro series wave connecting rod bolts so everything's ARP? Kids will have holes in their shoes for another paycheck, but oil will be controlled and the bottom end solid, right?

The stock rod bolts looked ok, but the ARP were WAY nicer looking. Greased em up. Torqued them to stock 25 lb specs and measured stretch - almost nothing. Took them up 5 lbs. Maybe .003 to .004" stretch. At 35 lbs they didn't even stretch .005"?? Ok, I'm stopping, calling ARP tech support, and he said, "...yes, to take advantage of the higher clamping power of ARP hardware, you've got to take em to .007" stretch, but NO MORE, which could be near 40 lbs torque, depending on which ARP grease you used, but torque doesn't matter." I asked, what about the bearing clearances if we've just dang near doubled the ft lbs torque on these things? He said, "Oh, and of course you need to have your bearings re-clearanced to match your new clamping pressure or that's gonna be one short lived motor...."

Well don't I have a way of getting myself in too deep? Hell-to-the-no I'm not tearing it back down and sending it through the machine shop again. We're talking about MAYBE a mild 325 hp build here, right? I just don't want to snap a main bolt, if say, someday I put a little turbo on it or___?

Ok so what torque specs should I use? Stock torque specs plus a little 'omph'? What numbers have you guys used? I hardly believe +5 lbs could be changing these clearances, do you?
 

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Torque them to Ford specs. Yes, they are capable of more torque but more torque equals more distortion which is why the builder mentioned resizing the rods to keep the hole round. Same deal with the main caps.

The advantage of the bolts not stretching as much as stock hardware is that they will be more stable at higher rpms.
 
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