I figured this has been talked about but I cant seem to find anything in the no-search engine. Do I reuse stock main and rod bolts or should I spend the money on ARP bolts or studs? My engine is not going to be high hp, just warmed over. Thanks Jake
Stock bolts or ARP?
- Thread starter jake
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70bigblockdodge
Old Man with a Hat
I have always used the stock ones over unless I'm planning on spinning it higher than 6000 rpm, and if that's the case the cast pistons need to go
I've always read that rod bolts were like the number one wise to upgrade thing and that those and head bolts in general should always be replaced based on the fact that once stretched their integrity or clamping ability is diminished. Having said that I've never changed head bolts although I haven't had the heads off that many engines and never built a seriously high HP engine.
I've done a number of 440 engines and I do the following:
ARP rod bolts. No exception... They are the best and if you compare them visually to the stock ones you will see why. I always replace the old bolts when rebuilding. Loctite the nuts too. Again, no exception.
Head bolts can be reused on a low mileage engine, but I would replace and at the very least use hardened washers.
Same for the main bolts. Hardened washers will let you torque the bolts more evenly.
Unless you are mounting a supercharger to it, I wouldn't even think about using studs for either place. They won't do anything for you except making it harder to put together and a lot harder to take apart again.
ARP rod bolts. No exception... They are the best and if you compare them visually to the stock ones you will see why. I always replace the old bolts when rebuilding. Loctite the nuts too. Again, no exception.
Head bolts can be reused on a low mileage engine, but I would replace and at the very least use hardened washers.
Same for the main bolts. Hardened washers will let you torque the bolts more evenly.
Unless you are mounting a supercharger to it, I wouldn't even think about using studs for either place. They won't do anything for you except making it harder to put together and a lot harder to take apart again.
tbm3fan
Old Man with a Hat
I just finished converting my Ford 360 into a 390. That meant having to locate a 390 crank and the 390 short rods. To be safe the rod bolts were replaced with ARP bolts since their history was unknown. When I do my 410 and when I do the Mopar 360 next year both will get ARP. The stock mains were reused in the 390 and will be in the other two.
Yatzee
Active Member
This I can tell you as I have been a millwright for 37 years. Change the bolts but you don't have to get
really expensive about it. Any quality good Grade 10 bolt will do and save you cash for something else.
You don't see them under the pan so you don't have to worry about impressing any one. All threaded
holes should be retapped as the bolts stretch the internal threads causing varying torque pressures
weather dry or wet. After retapping the holes they should be followed by a chase, not a tap to take the
sharp edges off the threads in the holes. Use "bottoming" taps and thread chasers only. If you skip
this most important step, it won't matter who's bolts you use because the job will have been done
improperly. This method holds true for any high torque fastener even head bolts.
really expensive about it. Any quality good Grade 10 bolt will do and save you cash for something else.
You don't see them under the pan so you don't have to worry about impressing any one. All threaded
holes should be retapped as the bolts stretch the internal threads causing varying torque pressures
weather dry or wet. After retapping the holes they should be followed by a chase, not a tap to take the
sharp edges off the threads in the holes. Use "bottoming" taps and thread chasers only. If you skip
this most important step, it won't matter who's bolts you use because the job will have been done
improperly. This method holds true for any high torque fastener even head bolts.
67Monaco
Old Man with a Hat
Roll tap or cutting tap? And, if you do use a roll tap would you really need to use a chase afterwards?
Cutting tap. A roll tap does exactly that... it rolls or forms the thread rather than cutting it. Quite often a roll tap is used in aluminum. It gives a stronger thread.
The cutting tap will cut threads.
In this case, the cutting tap cleans the junk out of the threads.
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The cutting tap will cut threads.
In this case, the cutting tap cleans the junk out of the threads.
Posted via Topify on Android
67Monaco
Old Man with a Hat
Groovy.
moper
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Rods bolts should be upgraded - but you must have the rods resized when you change the fasteners to something other than factory or stock replacement. No need to change the main fasteners, but just like the rods, if you go with studs, the mains will need to be align honed as the studs will change the way the block deforms when torqued, and can change bearing clearances.
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